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Endogenous progesterone and its cellular binding sites in wheat exposed to drought stress
... However, the specific bindings of progesterone were 4.9 and 21.3 fmol/mg protein in the non-vernalized and vernalized wheat cell cytosolic fractions, respectively [40]. Janeczko et al. [41] confirmed that specific progesterone binding sites exist in the wheat cell membrane and cytoplasm, and the number of binding sites varies with differing drought-resistant varieties and water conditions. This suggests that steroid binding proteins are present in wheat, and that the membrane and cytoplasm content of steroid binding proteins varies significantly with vernalization and drought treatment. ...
... However, the specific bindings of progesterone were 4.9 and 21.3 fmol/mg protein in the non-vernalized and vernalized wheat cell cytosolic fractions, respectively [40]. Janeczko et al. [41] confirmed that specific progesterone binding sites exist in the wheat cell membrane and cytoplasm, and the number of binding sites varies with differing droughtresistant varieties and water conditions. This suggests that steroid binding proteins are present in wheat, and that the membrane and cytoplasm content of steroid binding proteins varies significantly with vernalization and drought treatment. ...
... Triticum aestivum [41] Overexpressing mammalian CYP11A1 in tomato can significantly increase tolerance to drought and long-term dehydration. ...
Progesterone is a steroid hormone that performs important functions in mammals. However, studies on its physiological functions in plants have gradually increased in recent years. Therefore, this review summarizes the regulatory functions of progesterone on plant growth and development, as well as its response to stress. Moreover, the plant metabolic processes of progesterone are also discussed. Overall, progesterone is ubiquitous in plants and can regulate numerous plant physiological processes at low concentrations. Since progesterone shares similar characteristics with plant hormones, it is expected to become a candidate for plant hormone. However, most of the current research on progesterone in plants is limited to the physiological level, and more molecular level research is needed to clarify progesterone signaling pathways.
... The amount of BR in spring wheat rarely reaches 1 ng g −1 F.W. and most often is significantly lower than 1 ng and on average is about 300 pg (Janeczko and Swaczynová, 2010). Similarly, the amount of progesterone that is found in the spring cultivars of wheat is significantly less than 1 ng g −1 F.W. (Janeczko et al., 2013). ...
... This steroid was found in our studies both in not hardened and cold hardened winter wheat (Fig. 3 A). We earlier reported presence of progesterone in spring wheat (Janeczko et al., 2013), but to the best of our knowledge, the endogenous changes of progesterone have not been studied in respect to cold hardening or cold stress. In current studies, the content of progesterone decreased during cold hardening (in four of the cultivars, the effect was statistically significant) (Fig. 3 A). ...
... Kobiera after a period of cold hardening although its exogenous application simultaneously increased the activity of the antioxidant system and increased the frost tolerance of winter wheat. Our earlier studies, which were devoted to drought stress, showed that the progesterone content decreased after a drought period in the spring wheat cultivar that was susceptible to drought but increased in the tolerant cultivar (Janeczko et al., 2013). In current experiment, we did not find comparison in pairs within one cultivar between not hardened and cold-hardened plants. ...
The purpose of experiments was to describe the alterations of content of steroid regulators (brassinosteroids, progesterone) during cold hardening of winter wheat. Further we studied physiological and biochemical changes induced by these steroids in cold hardened winter wheat together with estimation of plant frost tolerance. The endogenous brassinosteroid content was elevated in winter wheat during cold hardening while level of progesterone was lowered. A higher content of brassinosteroids (but not progesterone) was connected to better frost tolerance of winter wheat cultivars. Plant supplementation with brassinosteroid (24-epibrassinolide) and progesterone before cold hardening reduced frost damage. Tests with the inhibitors of the biosynthesis of brassinosteroids and progesterone suggested that these steroids are one of players in regulating the antioxidant system in winter wheat during cold hardening. Their role in regulating the expression of Rubisco or the Rubisco activase gene was less clear. Steroid regulators did not affect the content of the stress hormone ABA. Model studies of the membranes, made on a Langmuir bath, showed an increase in the value of the parameter describing differences in membrane compressibility (resulting from stronger interactions among the molecules in the monolayers). This suggests that 24-epibrassinolide and progesterone enter into the lipid layer and - in a similar way to sterols – stabilise the interaction among lipids. It may be significant step for better frost tolerance. The use of steroid regulators (especially brassinosteroids) as agrochemicals improving frost tolerance of winter cereals will be discussed.
... Except for BRs also other steroids (like progesterone -PRO) can regulate growth and development or alleviate low temperature stress in plants [17][18][19]. PRO is a mammalian steroid hormone found also in plants [20,21]. Little is known about its role in plants, and the mechanism of its action is barely known. ...
... We postulate that cell membranes may be one of steroid targets in process of formation of cold/frost resistance. Although the protein membrane receptors responsible for the binding of BRs and PRO have been identified in plants [17,21,22], due to the similarity of the chemical structure of BRs (and PRO) to sterol components of membranes also their direct incorporation in the lipid membrane structure may be assumed. Under thermal stress associated with increased unsaturation of fatty acids, BRs would be placed in the hydrophobic part of the membranes in locations of their "loosened" integrity. ...
... As BRs of the potential ability to "integrate" with the lipid monolayers -24 epibrassinolide (EBR) and 24-epicastasterone (ECS)the precursor of EBR ( Fig. 1 A and B) were selected. Moreover, as a representative of the polar compounds of the steroid structureprogesterone (PRO, Fig. 1C),a mammalian hormone, whose presence in wheat cells has also been demonstrated [21], was used. ...
Steroids constitute one of the most important groups of compounds of regulatory properties both in the animal and plant kingdom. In plants, steroids such as brassinosteroids or progesterone, by binding to protein receptors in cell membranes, regulate growth and initiate processes leading to increased tolerance to stress conditions. Due to their structural similarities to sterols, these steroids may also directly interact with cellular membranes. Our aim was to determine the changes of the structural parameters of lipid membranes under the influence of hydrophobic steroid compounds, i.e. 24-epibrassinolide (EBR) and its precursor - 24-epicastasterone (ECS) and progesterone (PRO). Lipids were isolated from wheat seedlings with different tolerances to frost, grown at low temperatures (5°C) for 1.5 and 3 weeks (acclimation process). Control plants were cultured continuously at 20°C. From galactolipids and phospholipids, the main polar lipid fractions, the monolayers were formed, using a technique of Langmuir trough. EBR and ECS were introduced into monolayers, together with lipids, whereas the PRO was dissolved in the aqueous sub-phase upon which the monolayers were spread. Measurements performed at 25°C and 10°C showed a significant action of the tested compounds on the physicochemical properties of the monolayers. EBR and PRO increased the area per lipid molecule in monolayers, resulting in formation of more flexible surface structures while the presence of the ECS induced the opposite effect. The influence of the polarity of lipids and steroids on the interactions in the monolayer was discussed. Lipids extracted from the membranes of wheat with the most tolerance to frost were characterized by the highest fatty acid unsaturation and steroids had a relatively weak effect on the parameters of the structure of their monolayers.
... Binding sites for progesterone in the cells were also studied in vernalized and non vernalized winter wheat [101,102]. They are localized in both the cytoplasm and the cell membranes (microsomal fraction) [101,102]. ...
... Binding sites for progesterone in the cells were also studied in vernalized and non vernalized winter wheat [101,102]. They are localized in both the cytoplasm and the cell membranes (microsomal fraction) [101,102]. The number of binding sites for progesterone located in the membrane fraction of seedlings and flag leaves increased significantly under drought in the cv. ...
... Changes in the amount of progesterone and its binding sites in the cell under the influence of drought were then different depending on whether the cultivar was tolerant or sensitive to drought. The results suggest that progesterone is a part of wheat response to stress factors (drought) [102]. ...
In plants androstanes, estranes, pregnanes and corticoids have been described. Sometimes 17β-estradiol, androsterone, testosterone or progesterone were summarized as sex hormones. These steroids influence plant development: cell divisions, root and shoot growth, embryo growth, flowering, pollen tube growth and callus proliferation. First reports on the effect of applicated substances and of their endogenous occurrence date from the early twenties of the last century. This caused later on doubts on the identity of the compounds. Best investigated is the effect of progesterone. Main steps of the progesterone biosynthetic pathway have been analyzed in Digitalis. Cholesterol-side-chain-cleavage, pregnenolone and progesterone formation as well as the stereospecific reduction of progesterone are described and the corresponding enzymes are presented. Biosynthesis of androstanes, estranes and corticoids is discussed. Possible progesterone receptors and physiological reactions on progesterone application are reviewed.
Copyright © 2015. Published by Elsevier Inc.
... Progesterone and its receptors have been also found in plants, and recent studies, based on the latest analytical methods, particularly contributed to this discovery [9][10][11][12][13]. However, the physiological role of progesterone in plants is not yet clear. ...
... We know that the biosynthesis of progesterone in plants occurs in a similar way as in humans (see the review by Janeczko [21]). Progesterone binding proteins are present in plants too and some have structural similarity to the human progesterone receptor [9,13]. Therefore, it is very likely that inhibitors of progesterone biosynthesis (trilostane) or its binding (mifepristone), transferred from medical sciences would also be active in plant cells. ...
... Katoda is more sensitive to drought than cv. Monsun [13]. The seeds of cv. ...
... Progesterone was also shown to decrease necrosis and ion leakage and improve photosystem II efficiency in Arabidopsis under a biotic stress, Pseudomonas syringae infection (Janeczko et al., 2013). Progesterone was also shown to play a role in various abiotic stresses. ...
... the molecule also protected wheat and chickpea seedlings from salt stress by both enzymatic and non-enzymatic antioxidative defense mechanisms and by increasing the anabolism of carbon compounds (Erdal, 2012b;Erdal & Dumlupınar, 2011). Progesterone mitigates drought, heat, and light stress in wheat by enhancing antioxidant defense system and photosystem II activity, by way of facilitating D1 protein phosphorylation (Janeczko et al., 2013;Su et al., 2014;Xue et al., 2017). Progesterone was also shown to protect chickpea and maize seedlings from chilling damage and to enter the lipid bilayer (Erdal & Genisel, 2016;Genisel et al., 2013). ...
Drought and salt stress are the most common abiotic stresses resulting in yield reduction or complete loss of agricultural production in recent years. Stress mitigation by external biostimulator molecules has been an active research topic recently. Neurotransmitters (NTs) dopamine and progesterone, found in both animal and plant kingdom were shown to take role in plant abiotic and biotic stress defense in limited number of studies. This study investigated the effects of exogenous dopamine and progesterone application in tomato seedlings under drought and salt stress by examining various morphological and physiological parameters (tissue length and weights, relative water content, ion leakage, malondialdehyde and proline levels), as well as expressions of various genes encoding enzymes; superoxide dismutase (FeSOD), catalase (CAT2), glutathione reductase (GR1), ascorbate peroxidase (APX1), 1-aminocyclopropane-1-carboxylic acid synthase (ACS2) and delta 1-pyrroline-5-carboxylate synthase (P5CS), that play a direct role in the antioxidative defense system or measured as stress indicators. The results showed that dopamine and progesterone alleviated drought stress mainly by increasing superoxide dismutase and catalase antioxidative enzyme gene expressions and decreasing ethylene production in tomato seedlings, thereby improving cell membrane integrity and increasing root dry weight. Although morphological and physiological responses of the seedlings were mostly similar under drought and salinity stresses, antioxidative defense enzyme gene expressions were not upregulated under salinity stress, except for the GR1 expression under progesterone treatment.
... After the determination of MSHs in plants, many studies were conducted regarding the presence, quantities, types, effects, and receptors of these steroids in various organs and tissues of many plant species in all developmental stages from germination to flowering [2][3][4][5]. The studies were focused on determining the effects of exogenous application of these steroids on the growth and development of plants, their tolerance to various stressors, and their mode of action in metabolism in recent years [6][7][8][9][10]. Among the MSHs, the most studied hormone concerning its effects on plants is progesterone. ...
... Like other MSHs, progesterone (PRG) also has a generally stimulating effect on all developmental stages of plants from germination to the flowering stage, and this effect was clearly revealed by the findings obtained from the studies regarding its effects on many parameters such as cell division, callus formation, root-stem elongation, pollen germination, protein, sugar, pigment, and phenolic substance contents in various plants [1,[12][13][14]. Moreover, progesterone was shown to have an improving effect on plant defense system activation against various biotic-abiotic environmental stress factors by activating both enzymatic and non-enzymatic antioxidant defense systems, and thus oxidative stress parameters [3,9,[15][16][17]. In spite of all these promoting effects of progesterone on plant growth and development and defense system, its mode of action is still not completely clarified. ...
This research aimed to investigate the effects of progesterone, a mammalian steroid sex hormone, on the mitochondrial respiration in germinating maize seeds. For this purpose, maize seeds were divided into four different groups (control, 10−6, 10−8, and 10−10 mol·L−1 progesterone) and were grown in a germination cabinet in the dark at 24.5 ± 0.5 °C for 4 d. The changes in gene expression levels of citrate synthase (CS), cytochrome oxidase (COX19), pyruvate dehydrogenase (Pdh1), and ATP synthase (ATP6), which is involved in mitochondrial respiration, were studied in root and cotyledon tissues. Significant increases were recorded in the gene expression levels of all studied enzymes. In addition, progesterone applications stimulated activities of malate synthase (MS), isocitrate lyase (ICL), and alpha-amylase, which are important enzymes of the germination step. The changes in gene expression levels of mas1 and icl1 were found parallel to the rise in these enzymes’ activities. It was determined similar increases in root and coleoptile lengths and total soluble protein and total carbohydrate contents. The most remarkable changes were detected in 10−8 mol·L−1 progesterone-treated seedlings. These results clearly indicate that progesterone stimulates mitochondrial respiration by inducing biochemical and molecular parameters and thus accelerates seed germination thanks to the activation of other pathways related to mitochondrial respiration.
... Since there was no extractable progesterone found in the soil at the end of the growing season, and the concentrations in urine varied greatly in different fields, it is more likely that the question is about the plants' own formation of progesterone. In the literature, there are indications that plants can form progesterone also naturally (Janeczko, 2012;Janeczko et al., 2013). The significance of endogenic progesterone to the plants, however, is unknown. ...
... In terms of progesterone, it is possible that there is endogenic production of it in cereal crops. According to Janeczko (2012), plants can produce progesterone without external accumulation and endogenic progesterone production has been found for example from wheat (Janeczko et al., 2013). Pharmaceuticals in urine can be a limiting factor for the fertiliser use, if they are found in large amounts. ...
The growing demand for food and the increasing costs of cultivation are posing a challenge for agriculture. Diminishing phosphorus reserves, as well as the energy intensive method of producing nitrogen fertilisers are drivers for more intensive reuse of different organic fertilisers, such as manures and excreta. Source separation and fertilisation with human urine can be one option for nutrient reuse. Urine contains all the main nutrients as well as micronutrients in soluble form, but it also contains chemicals, like pharmaceuticals and hormones. The aim of this study was to examine the efficiency and safety of the use of source separated human urine as a fertiliser for barley (Hordeum vulgare). The fertiliser efficiency of source-separated urine was examined in field-scale experiments for the first time in Finland. Two separate cultivation experiments in two fields and barley varieties were conducted. The efficiency of urine as a fertiliser was compared to corresponding amount of mineral fertiliser. No fertiliser was applied to one plot in order to create a reference treatment. The two experiments were conducted using variety Wolmari with 54 kg N ha−1 and variety Harbinger with 100 kg N ha−1. The barley grain and straw yield grown with urine fertiliser was equivalent to the yield in mineral fertilised plots. The growth of barley in both fertiliser treatments was slightly faster, compared to non-fertilised treatment. There were no significant differences between the treatments in terms of protein content of the grain although the results varied in terms of the thousand grain weight (TGW) and germination. The urine analyses indicated that there were no pathogen indicators, nor heavy metal concentrations, exceeding the limit values set by legislation. The main nutrient concentrations (N, P, K) would also meet the requirements for a fertiliser product according to Finnish legislation. Pharmaceuticals and hormones were found from the urine, but apart from progesterone, all of them presented extractable values in soil below the detection limits, and they were not detected in measurable amounts in barley grain at the end of the growing season. These results suggest that source separated urine could be an efficient fertiliser in crop cultivation.
... Selected mammalian steroids, exogenously deposited, stimulate plant cell division, the maturation of pollen as well as growth and flowering [24]. Progesterone, estrone and androsterone induce in vitro flowering in Arabidopsis thaliana [25]. ...
... Exogenous application of MSHs activate the oxidative enzymes under non-stress conditions [26]. The latest results obtained in spring wheat after drought treatment [24] suggest that progesterone and its putative receptors contribute in processes regulating plant interactions with the environment. Thus, exogenous application of MSHs may be used to increase the plant resistance to negative environmental conditions. ...
Most flowering plants, including important crops, require double fertilization to form an embryo and endosperm, which nourishes it. Independence from fertilization is a feature of apomictic plants that produce seeds, from which the plants that are clones of the mother plant arise. The phenomenon of apomixis occurs in some sexual plants under specific circumstances. Since the launch of a fertilization-independent mechanism is considered a useful tool for plant breeding, there have been efforts to artificially induce apomixis. We have been able to produce fertilization-independent endosperm in vitro in Arabidopsis over the last few years. This paper demonstrates the methods of improving the quality of the endosperm obtained using plant and mammalian steroid hormones. Additionally, it shows the study on the autonomous endosperm (AE) formation mechanism in vitro. This paper examines the effect of exogenous steroid hormones on unfertilized egg and central cell divisions in culture of unpollinated pistils of Arabidopsis Col-0 wild-type and fie-1 mutant. All media with hormones used (estrone, androsterone, progesterone, and epibrassinolide) stimulated central cell divisions and fertilization-independent endosperm development.
The stages of AE development followed the pattern of Arabidopsis thaliana wild type after fertilization. Subsequent stages of AE were observed from 2-nuclear up to cellular with the most advanced occurring on medium with 24-epibrassinolide and progesterone. The significant influence of mammalian sex hormones on speed of AE development and differentiation was noticed. Using restriction analysis, the changes in methylation of FIE gene was established under in vitro condition. The authors of this paper showed that Arabidopsis thaliana has a high potency to fertilization-independent development.
... They also are synthesized by plants, in 128 species representing more than 50 families ( Janeczko & Skoczowski 2005, and references therein). Selected steroids applied exogenously to plants stimulate cell division, pollen maturation, growth and flowering ( Janeczko et al. 2003( Janeczko et al. , 2013. In Arabidopsis thaliana, estrone stimulated induction of flowering in vitro ( Janeczko & Filek 2002). ...
... Based on molecular data on the signaling pathway of steroid plant hormones ( Janeczko 2012) and their role in auxin redistribution, vernalization, flowering, and regulatory mechanisms in response to environmental stress ( Janeczko et al. 2013), we expected estrone to stimulate somatic and female gametophyte cell division, proliferation and differentiation. In fact, we observed direct organogenesis induced by this mammalian hormone in both hypocotyl and cotyledon explants. ...
The aim of the study was to determine the effect of the mammalian female sex hormone estrone on differentiation of somatic tissues and on induction of autonomous endosperm in culture of female gametophyte cells of Arabidopsis thaliana ecotype Columbia (Col-0).
In culture, estrone-stimulated development of autonomous endosperm (AE) occurred in 14.7% of unpollinated pistils. The AE represented development stages similar to those of young endosperm after fertilization and AE of fis mutants in vivo. In the majority of ovules the AE was in a few-nucleate young stage. Some ovules showed more advanced stages of AE development, with nuclei and cytoplasm forming characteristic nuclear cytoplasmic domains (NCDs). Sporadically, AE was divided into regions characteristic for Arabidopsis endosperm formed after fertilization.
Direct organogenesis (caulogenesis, rhizogenesis), callus proliferation and formation of trichome-like structures were observed during in vitro culture of hypocotyls and cotyledons of 3-day-old seedlings cultured on medium supplemented with estrone for 28 days. Histological analysis showed adventitious root formation and changes in explant anatomy caused by estrone.
... None of these were found in the soil or the barley grain at the end of the growing season when using urine as a fertilizer (Table 1) (Viskari et al. 2018a, b). Only exception was progesterone, which plants can also produce endogenously (Janeczko et al. 2013). Despite the fact, that source separated urine treated according to WHO (2006) guidelines, does not seem pose a risk to environment or human health (Table 2), there is still a resistance and biased attitudes against the use of it. ...
About 80% of all wastewaters worldwide are discharged to the environment without any or with inadequate treatment. This means loss of all nutrients in the wastewater and even if wastewater is treated, there are significant nutrient losses during the process. Human urine forms only a fraction of the wastewater flow by volume, but contains majority of nitrogen and phosphorus, which are essential nutrients for plant growth. To ensure the food security and maximum reuse of nutrients from side streams and wastes, also our own excreta—especially source separated urine—needs to be taken into use as a raw material for fertilizer products. There are several indications of the safe and efficient use of stored urine as a fertilizer in agriculture per se. Issues of concern are pharmaceuticals and micropollutants as well as risk of spreading pathogens when using in urine as fertilizer, but with proper treatment these can be minimized. Furthermore, the environmental benefits of urine separation and reuse are shown in several LCA studies. With an appropriate treatment, urine volume can be reduced, nutrients can be concentrated and recovered to increase the value and enable safe use of the nutrients. Several technologies to treat urine exist already, and can be implemented especially in developing areas, where centralized wastewater treatment is missing. The acceptance of urine separation and reuse seem to be more institutional and related to regulation and existing norms, rather than functionality of the treatment technologies or safety of the end-products. Consumers are more willing to accept the urine use as a fertilizer if it is safe and not increasing costs. In this paper these different aspects of urine separation and use as a fertilizer product are discussed.
... In plants, the steroid regulators include the brassinosteroids, which are hormones that have a multidirectional activity and are engaged in plant growth, development, and its response to environmental stresses [5,6]. Interestingly, however, mammalian steroid hormones are also part of the metabolic profile in plants [7,8]. While the debate about whether these compounds are also hormones for plants is still open, currently, there is a great deal of literature data to show that mammalian steroids influence the physiological processes of plants. ...
Although the only known steroid hormones in plants are brassinosteroids, interestingly, mammalian steroid hormones such as androgens or estrogens are also part of the plant metabolic profile. This presented review is focused on the progress that has been made in this matter during the last two decades. The presence of testosterone, 17β-estradiol, and other androgens/estrogens in plants (particularly those that can be measured using more advanced techniques) is described. The physiological activity of androgens and estrogens, especially in plants’ stress response, are discussed, together with some possible mechanisms of their action. The current knowledge indicates that although androgens and estrogens do not have the status of hormones in plants, they are physiologically active and can serve as regulators that support the activity of classic hormones in (1) regulating the various processes connected with plant growth and development and (2) the interaction of plants with their environment.
... We assessed their content of free sugars, total soluble sugars, starch, and the average polymerization degree of soluble oligocarbohydrates in four replicates. The analysis was conducted using a method of Janeczko et al. [50], described and modified by Hura et al. [51]. Prior to the analysis the plant material was frozen in liquid nitrogen, then freeze-dried and homogenized (MM 400, Retsch, Haan, Germany). ...
An energy-saving light emitting diode (LED) system allows for adjustment of light quality, which affects plant development and metabolic processes in in vitro cultures. The study investigated the content of endogenous carbohydrates and the condition of the photosynthetic apparatus of Gerbera jamesonii Bolus ex Hook. f. Our aim was to analyze the effects of different LED light qualities—100% red light (R LED), 100% blue (B LED), a mixture of red and blue (7:3) (RB LED), and a fluorescent lamp as a control (Fl)—during the multiplication of axillary shoots. After 40 days, the culture measurements were performed using a non-invasive pulse amplitude modulation (PAM) fluorimeter. Sugar content was assessed with high performance liquid chromatography (HPLC). Two forms of free monosaccharides (glucose and fructose), two sugar alcohol derivatives (inositol and glycerol), and seven forms of free oligosaccharides were identified. Of those, glucose content was the highest. LEDs did not disturb the sugar metabolism in multiplied shoots. Their monosaccharides were three times more abundant than oligosaccharides; the same results were found in plants grown under control light. R light depleted the performance of the photosynthetic apparatus and caused its permanent damage. The RB LED spectrum ensured the most efficient non-photochemical quenching of the photosystem II (PS II) excitation state and high shoot quality.
... Progesterone was reported to occur in many plant species (Janeczko and Skoczowski 2005;Pauli et al. 2010) and exogenous progesterone influenced plant growth (Bhattacharya and Gupta 1981). It has a positive impact on abiotic stress resistance in a broad range of crops (Janeczko et al. 2013;Genisel et al. 2013;Hao et al. 2019). We, therefore, considered the cardenolide formation observed in a developmental context as "constitutive" biosynthesis (connected to the constitutive expression of DlP5βR1) and "stress-induced" biosynthesis (connected to the inducible expression of DlP5βR2 (Fig. 5a)). ...
Studying RNAi-mediated DlP5βR1 and DlP5βR2 knockdown shoot culture lines of Digitalis lanata, we here provide direct evidence for the participation of PRISEs (progesterone 5β-reductase/iridoid synthase-like enzymes) in 5β-cardenolide formation. Progesterone 5β-reductases (P5βR) are assumed to catalyze the reduction of progesterone to 5β-pregnane-3,20-dione, which is a crucial step in the biosynthesis of the 5β-cardenolides. P5βRs are encoded by VEP1-like genes occurring ubiquitously in embryophytes. P5βRs are substrate-promiscuous enone-1,4-reductases recently termed PRISEs (progesterone 5β-reductase/iridoid synthase-like enzymes). Two PRISE genes, termed DlP5βR1 (AY585867.1) and DlP5βR2 (HM210089.1) were isolated from Digitalis lanata. To give experimental evidence for the participation of PRISEs in 5β-cardenolide formation, we here established several RNAi-mediated DlP5βR1 and DlP5βR2 knockdown shoot culture lines of D. lanata. Cardenolide contents were lower in D. lanata P5βR-RNAi lines than in wild-type shoots. We considered that the gene knockdowns may have had pleiotropic effects such as an increase in glutathione (GSH) which is known to inhibit cardenolide formation. GSH levels and expression of glutathione reductase (GR) were measured. Both were higher in the Dl P5βR-RNAi lines than in the wild-type shoots. Cardenolide biosynthesis was restored by buthionine sulfoximine (BSO) treatment in Dl P5βR2-RNAi lines but not in Dl P5βR1-RNAi lines. Since progesterone is a precursor of cardenolides but can also act as a reactive electrophile species (RES), we here discriminated between these by comparing the effects of progesterone and methyl vinyl ketone, a small RES but not a precursor of cardenolides. To the best of our knowledge, we here demonstrated for the first time that P5βR1 is involved in cardenolide formation. We also provide further evidence that PRISEs are also important for plants dealing with stress by detoxifying reactive electrophile species (RES).
... Eventually, several plant enzymes that are putatively involved in the synthesis of mammalian-like sex hormones were found, but the majority of results are on the level of mechanical assumptions. However, one research even proposed the possible mechanism of unusual steroidogenesis in plants that involves progesterone 5α-reductase, ketoisomerases, and dehydrogenases to produce progesterone and corticosteroids [156], and appropriate receptors relevant to these steroids were detected in cytosolic and microsomal fractions of plant organs [157,158]. The crucial role and necessity of such mammalian-like hormones in plants are debatable, but it is believed that, for example, progesterone can be involved in stress response and regulation of growth in plants while estradiol may affect plants flowering. ...
The way of plant sterols transformation and their benefits for humans is still a question under the massive continuing revision. In fact, there are no receptors for binding with sterols in mammalians. However, possible biotransformation to steroids that can be catalyzed by gastro-intestinal microflora, microbial cells in prebiotics or cytochromes system were repeatedly reported. Some products of sterols metabolization are capable to imitate resident human steroids and compete with them for the binding with corresponding receptors, thus affecting endocrine balance and entire physiology condition. There are also tremendous reports about the natural origination of mammalian steroid hormones in plants and corresponding receptors for their binding. Some investigations and reports warn about anabolic effect of sterols, however, there are many researchers who are reluctant to believe in and have strong opposing arguments. We encounter plant sterols everywhere: in food, in pharmacy, in cosmetics, but still know little about their diverse properties and, hence, their exact impact on our life. Most of our knowledge is limited to their cholesterol-lowering influence and protective effect against cardiovascular disease. However, the world of plant sterols is significantly wider if we consider the thousands of publications released over the past 10 years.
... 51 There is evidence that resveratrol can act by multiple mechanisms in animal tissues and organs, including as an agonist of estrogen hormones. 52 Resveratrol is structurally similar to the synthetic estrogen diethylstilbestrol and exhibits variable degrees of estrogen receptor agonism in different animal cells. 53 The existence of a steroid receptor in plants has been reported 52,54 and mammalian steroid sex hormones, which include progesterone, 17β-oestradiol, and testosterone, are naturally produced by plants. ...
... Progesteronin osalta voidaan todeta, että sitä on viime vuosien aikana tehdyissä tutkimuksissa todettu esiintyvän kasveissa myös luonnostaan (Janeczko, 2012), mutta sen merkitystä kasveille ei vielä tunneta. Endogeenistä progesteronia on määritetty esimerkiksi vehnästä (Janeczko, et al., 2013). ...
... Our knowledge about the roles of progesterone in plants is very limited. Progesterone has been shown to participate in plant development and abiotic stress responses (Janeczko, 2012;Janeczko et al., 2013a). Contrary to brassinosteroids, progesterone has no hormone status in plants, so every study devoted for the evaluation of its physiological functions in plants will be helpful for the evaluation of its hormonal nature. ...
Phytohormone levels and the expression of genes encoding key enzymes participating in hormone biosynthetic pathways were investigated in pepper leaves inoculated with two different tobamoviruses. Obuda pepper virus (ObPV) inoculation led to the development of hypersensitive reaction (incompatible interaction), while Pepper mild mottle virus (PMMoV) inoculation resulted in a systemic, compatible interaction. ObPV-inoculation markedly increased not only the levels of salicylic acid (SA) (73-fold) and jasmonic acid (8-fold) but also those of abscisic acid, indole-3-acetic acid, indole-3-butyric acid, cis-zeatin, cis-zeatin-9-riboside and trans-zeatin-9-riboside in the inoculated pepper leaves 3 days post inoculation. PMMoV infection increased only the contents of gibberellic acid and SA. Hormone contents did not change significantly after ObPV or PMMoV infection in non-infected upper leaves 20 days post inoculation. Concentrations of some brassinosteroids (BRs) and progesterone increased both in ObPV- and PMMoV inoculated leaves. ObPV inoculation markedly induced the expression of three phenylalanine ammonia-lyase (PAL) and a 1-aminocyclopropane-1-carboxylate oxidase (ACO) genes, while that of an isochorismate synthase (ICS) gene was not modified. PMMoV inoculation did not alter the expression of PAL and ICS genes but induced the transcript abundance of ACO although later than ObPV. Pre-treatment of pepper leaves with exogenous 24-epi-brassinolide (24-epi-BR) prior to ObPV-inoculation strongly mitigated the visible symptoms caused by ObPV. In addition, 24-epi-BR pre-treatment markedly altered the level of several hormones in pepper leaves following ObPV-inoculation. These data indicate that ObPV- and PMMoV-inoculations lead to intricate but well harmonized hormonal responses that are largely determined by the incompatible or compatible nature of plant-virus interactions.
... Sugars were analyzed according to the method reported by Janeczko et al. (2013), with modifications. About 10 mg of lyophilized and homogenized samples was extracted in 1 ml of ultra-pure water (Option R, Elga, UK) by shaking for 15 min at 30 Hz (MM 400, Retsch, Germany). ...
Abstarct
5β-Cardenolides are pharmaceutically important metabolites of the specialized metabolism of Digitalis lanata. They were used over decades to treat cardiac insufficiency and supraventricular tachycardia. Since the 1960s, plant scientists have known that progesterone is an essential precursor of cardenolide formation. Therefore, plant progesterone biosynthesis was mainly analyzed in species of the cardenolide-containing genus Digitalis during the following decades. Today, Digitalis enzymes catalyzing the main steps of progesterone biosynthesis are known. Most of them were found in a broad range of organisms. This review will summarize the findings of 60 years of research on plant progesterone metabolism with a particular focus on the recent results in Digitalis lanata and other plants.
Memeli cinsiyet hormonları arasında yer alan ve bitkilerde de doğal olarak bulunan progesteron, çimlenmeden çiçeklenmeye kadar tüm bitki gelişim safhaları üzerine önemli uyarıcı etkilere sahiptir. Ancak bu hormonun etki mekanizması halen tam olarak aydınlatılamadığı gibi, sebep olduğu etkilerin de direkt olarak kendinden mi kaynaklandığı yoksa farklı yolaklar üzerinden dolaylı olarak mı gerçekleştiği halen bilinmemektedir. Bu amaçla, mevcut araştırmada progesteron reseptör antagonisti olan mifepriston kullanılmak suretiyle, progesteronun etkisinin doğrudan mı yoksa dolaylı mı olduğu belirlenmeye çalışılmıştır. 9 günlük mısır fideleri 4 gruba ayrılarak yapraklarına saf su (kontrol grubu), progesteron (0.1 µmol.L-1), mifepriston (5.8×10-5 mmol.L-1) ve progesteron + mifepriston) solüsyonları püskürtülmüş ve tüm gruplar üç gün sonra hasat edilerek çeşitli analizler yapılmıştır. Progesteron uygulaması bitkilerin kök ve yaprak uzunluları ile total klorofil ve kuru madde içeriklerinde kontrol bitkilerine kıyasla önemli artışlara sebep olurken, mifepriston uygulanan bitkilerde bu parametrelerin tamamında belirgin düşüşler kaydedildi. Progesteron ile birlikte mifepriston uygulanan bitkilerde ise kontrol bitkilerine kıyasla istatistiki olarak önemli bir değişim meydana gelmedi. Tek başına mifepriston uygulaması ise bu parametrelerde belirgin bir inhibisyona neden oldu. Tüm bu bulgular, mifepriston uygulamasının progesteronun bağlanmasını önlemek suretiyle progesteron bağlantılı metabolik faaliyetlerin gerçekleşmesine ket vurarak mısır fidelerinin büyüme ve gelişmesini inhibe ettiğini ve böylelikle progesteronun bitki metabolizması üzerine doğrudan etkiye sahip olduğunu açıkça ortaya koymaktadır.
Countercurrent separation (CCS) has been widely used for the separation of high abundance compounds. However, the identification of low abundance compounds, such as mammalian steroid hormones, from natural sources is still a challenging task. A mixture of 14 human steroid hormone reference compounds was prepared for the development of a CCS enrichment strategy. The TLC-based GUESS (Generally Useful Estimate of Solvent Systems) method along with partitioning experiments were implemented to develop a process for the enrichment of these low abundance compounds with CCS. The application of CCS to the steroid hormone enrichment of Vitex negundo extracts was demonstrated by the identification of progesterone and estriol. This method provides a CCS-driven strategy to mine plant sources for low abundance compounds.
Understanding of the physiological role of mammalian hormone—androstenedione (AN)—in plants is scant and the mechanisms of its action at a cellular level are practically unknown. The aim of this study was to investigate the physicochemical and biochemical background of AN activity in winter wheat exposed to low temperature. Cold periods are important in the lifecycle of this species as they induce frost resistance and further generative development. Wheat seedlings (control and AN-supplemented) were acclimated 2 weeks in cold and then exposed to frost (−12 °C). AN supplementation reduced frost damages by 30%. Moreover, AN also accelerated generative development of wheat. The AN-induced changes in redox homeostasis seemed to be important for processes of acclimation to low temperature and generative induction. AN influenced hormonal balance in wheat and stimulated accumulation among other gibberellins and cytokinins. For example, in aerial part of plants, the content of GA3 was increased by AN in 12 days of cold by about 30%, whereas the content of cis-zeatin was increased by 65%. AN was absorbed into plant membranes (Langmuir bath studies). The membrane absorption of AN increased the distance between lipid molecules and this may be an important step in the AN-induced enhancement of frost resistance. AN interaction with lipid membranes showed similarity to the interactions of some known regulators stimulating flowering in plants, and thus it may also underlie the acceleration of wheat development. Androstenedione was naturally present in wheat leaves (5–21 pg g⁻¹ FW).
Foods and botanical supplements can interfere with the endocrine system through the presence of phytosteroids – chemicals that interact with steroids receptors. Phytoestrogens are well studied, but compounds such as kaempferol, apigenin, genistein, ginsenoside Rf, and glycyrrhetinic acid have been shown to interact with non-estrogen nuclear receptors. These compounds can have agonist, antagonist, or mixed agonist/antagonist activity depending on compound, receptor, cell line or tissue, and concentration. Some phytosteroids have also been shown to inhibit steroid metabolizing enzymes, resulting in biological effects through altered endogenous steroid concentrations. An interesting example, compound A (4-[1-chloro-2-(methylamino)ethyl]phenyl acetate hydrochloride (1:1)) is a promising selective glucocorticoid receptor modulator (SGRM) based on a phytosteroid isolated from Salsola tuberculatiformis Botschantzev. Given that $6.9 billion of herbal supplements are sold each year, is clear that further identification and characterization of phytosteroids is needed to ensure the safe and effective use of botanical supplements.
Experiments were conducted to investigate the effects of exogenous progesterone on photochemical efficiency of PSII and turnover of D1 protein under heat stress during the grain-filling stage. Heat stress resulted in increases of hydrogen peroxide production, malondialdehyde content, and relative electrolytic leakage in wheat leaves, but these responses were alleviated by foliar application of progesterone. Meanwhile, activities of superoxide dismutase, catalase, and peroxidase were significantly improved in progesterone-pretreated leaves. Along with the alleviation of oxidative stress, higher abundances of STN8 and phosphorylated D1 protein and lower total D1 protein content in the PSII reactive center were observed in progesterone-pretreated leaves relative to controls. Consequently, progesterone raised the potential photochemical efficiency, actual photochemical efficiency, and electron transfer rate. These results indicate that foliar application of progesterone can effectively alleviate heat-induced PSII damage by enhancing antioxidant capability and regulating phosphorylation of D1 protein in wheat leaves.
Drostanolone is one of the most frequently detected anabolic androgenic steroids in doping control analysis. Here, we studied drostanolone urinary metabolic profiles using liquid chromatography quadruple time of flight mass spectrometry (LC-QTOF-MS) in full scan and targeted MS/MS modes with accurate mass measurement. The drug was administered to one healthy male volunteer and liquid-liquid extraction along with direct-injection were used to analyze urine samples. Chromatographic peaks for potential metabolites were identified with the theoretical [M-H]- as a target ion in a full scan experiment and actual deprotonated ions were analyzed in targeted MS/MS mode. Eleven metabolites including five new sulfates, five glucuronide conjugates, and one free metabolite were confirmed for drostanolone. Due to the absence of useful fragment ions to illustrate the steroid ring structure of drostanolone phase II metabolites, gas chromatography mass spectrometry (GC-MS) was used to obtain structural details of the trimethylsilylated phase I metabolite released after enzymatic hydrolysis and a potential structure was proposed using a combined MS approach. Metabolite detection times were recorded and S4 (2α-methyl-5α-androstan-17-one-6β-ol-3α-sulfate) and G1 (2α-methyl- -5α-androstan-17-one-3α-glucuronide) were thought to be new potential biomarkers for drostanolone misuse which can be detected up to 24 days by liquid-liquid extraction and 7 days by direct-injection analysis after intramuscular injection. S4 and G1 were also detected in two drostanolone-positive routine urine samples.
The aim of study was to evaluate the usefulness of FT-Raman spectroscopy in assessing stress-induced metabolic changes in plants. 20-d-old optimally watered plants of soybean were exposed to drought. Metabolic changes in optimally watered and drought-stressed plants were monitored using FT-Raman spectroscopy. In parallel, analyses were carried out of fatty acid composition and pigment content using analytical methods. These compounds are associated with the response of plants to environmental stress. While fatty acid assays in study were inconclusive, the pigment content analysis gave promising results. FT-Raman experiment demonstrated a decrease in carotenoid content in leaf, as a result of drought, which was confirmed by spectrophotometric analysis. In addition to the analysis of aforementioned compounds, FT-Raman spectroscopy allowed the simultaneous observation of
a wider spectrum of compounds scattering the radiation in the leaves tested, and their subsequent comparative analysis. The impact of drought on metabolism of soybean was clearly visible on spectra and confirmed using cluster analysis. The technical problem of the influence of leaf water content on measurements, which appeared in studies, will be discussed. To conclude, FT-Raman spectroscopy may be a good complement to other non-invasive methods, e.g., fluorescent methods, in assessing the stress-induced damage of crops.
Effects of mammalian sex hormones (progesterone and (3-estradiol) on growth parameters (percentage of germination, root and shoot length) and activity of selected enzymes (a-amylase, superoxide dismutase, peroxidase, cata-lase and polyphenoloxidase) in germinating maize were studied. Maize seeds were germinated on Petri dishes in the solutions of steroids (concentrations: 10 -4 10-6, 10-9, 10-12, 10 -15M). Steroids in all tested concentrations significantly increased root and coleoptyle lengths as well as percentage of germination of maize in comparison to control. The highest germination ratio, root and coleoptyle lengths were recorded at 10-9M and 10-12M of both progesterone and β-estradiol. Likewise, progesterone and β-estradiol in all tested concentrations stimulated the activities of superoxide dismutase (SOD), peroxidase (POX), catalase (CAT), polyphenol oxidase (PPO) and aamylase. The highest activities of these enzymes were determined in endosperm of seeds under the influence of progesterone and Pestradiol at concentrations with the highest root and coleoptyle lengths as well as percentage of germination.
The aim of the present studies was to assess the possibility of compensating the negative effects of drought stress on gaseous exchange and efficiency of photosystem II in soybean seedlings by application of the androgen — androstenedione. Androstenedione (0.25 mg dm−3) was applied via presowing seed soaking (12 h). Control seeds were untreated with steroid. Plants were cultured in pots. On the 12th day of growth, the plants were watered for the last time. Drought symptoms occurred during the next 10 days. On the 22nd day of growth, leaf gaseous exchange and PSII measurements were taken. Afterwards the plants were watered. Two days later measurements were taken again. Androstenedione improved the intensity of leaf net photosynthesis. The effect of androstenedione was manifested during the rehydration of plants that have undergone a period of drought. An increase in net photosynthesis intensity was accompanied by higher transpiration. Possible mechanisms of androstenedione action — effect on aquaporin functionality and membrane stability — are discussed. The significance of ethanol and DMSO (solvents of steroid) in experiments on the physiological activity of androstenedione is also considered.
Brassinosteroids are known to protect plants against various abiotic and biotic stresses, however, very limited information is available about the role of progesterone. Therefore the effects of Pseudomonas syringae pv. syringae (P.s.) wild type strain 61, its hrcC mutant, and the saprophytic P. fluorescens (P.f.) strain 55 were investigated in wild type Arabidopsis thaliana cv. Columbia and its rbohF knock-out mutant, with and without progesterone pre-treatment. The reactions of wild type and rbohF mutant Arabidopsis to bacterial inoculations were similar, although 2 h after injection of P.s. a larger increase of electrolyte leakage was measured in wild type than in rbohF knockout mutant leaves. The hrcC mutant caused weak necrotic symptoms and increased leakage in both types of Arabidopsis, although to a much lesser extent than P.s. The P.f. did not induce any visible symptom, but slightly increased the electrolyte leakage in both types of Arabidopsis. Inoculation by all Pseudomonas bacteria led to significant alterations in photosystem 2 efficiency as compared to control plants. Pre-treatment of leaves with progesterone diminished the necrotic symptoms, the electrolyte leakage and improve the efficiency of photosystem 2 caused by Pseudomonas bacteria.
Cardiovascular disease remains the leading cause of death for both men and women. Hypertension is less prevalent in young women compared to young men, but menopausal women are at greater risk for hypertension compared to men of similar age. Despite these risks, women do not consistently receive first line treatment for the early stages of hypertension, and the greater morbidity in menopause reflect this neglect. This review focuses on ovarian hormone effects on the cardiovascular and water regulatory systems that are associated with blood pressure control in women. The study of ovarian hormones within young women is complex because these hormones fluctuate across the menstrual cycle, and these fluctuations can complicate conclusions regarding sex differences. To better isolate the effects of oestrogen and progesterone on the cardiovascular and water regulation systems, we developed a model to transiently suppress reproductive function followed by controlled hormone administration. Sex differences in autonomic regulation of blood pressure appear related to ovarian hormone exposure, and these hormonal differences contribute to sex differences in hypertension and orthostatic tolerance. Oestrogen and progesterone exposure are also associated with plasma volume expansion, and a leftward shift the osmotic operating point for body fluid. In young, healthy women, the shift in osmoregulation appears to have only a minor effect on overall body water balance. Our overarching conclusion is that ovarian hormone exposure is the important underlying factor contributing to differences in blood pressure and water regulation between women and men, and within women throughout the lifespan.
In the last decade, our understanding of the processes underlying plant response to drought, at the molecular and whole-plant levels, has rapidly progressed. Here, we review that progress. We draw attention to the perception and signalling processes (chemical and hydraulic) of water deficits. Knowledge of these processes is essential for a holistic understanding of plant resistance to stress, which is needed to improve crop management and breeding techniques. Hundreds of genes that are induced under drought have been identified. A range of tools, from gene expression patterns to the use of transgenic plants, is being used to study the specific function of these genes and their role in plant acclimation or adaptation to water deficit. However, because plant responses to stress are complex, the functions of many of the genes are still unknown. Many of the traits that explain plant adaptation to drought — such as phenology, root size and depth, hydraulic conductivity and the storage of reserves — are associated with plant development and structure and are constitutive rather than stress induced. But a large part of plant resistance to drought is the ability to get rid of excess radiation, a concomitant stress under natural conditions. The nature of the mechanisms responsible for leaf photoprotection, especially those related to thermal dissipation, and oxidative stress are being actively researched. The new tools that operate at molecular, plant and ecosystem levels are revolutionising our understanding of plant response to drought, and our ability to monitor it. Techniques such as genome-wide tools, proteomics, stable isotopes and thermal or fluorescence imaging may allow the genotype–phenotype gap to be bridged, which is essential for faster progress in stress biology research.
In the present study, it was aimed to investigate the influence of exogenous mammalian sex hormones (MSH) (progesterone, β-estradiol
and androsterone) on the morphological (root and shoot growth) and biochemical parameters (protein and sugar content, antioxidant
enzyme activities, and lipid peroxidation and H2O2 levels) of chickpea (Cicer arietinum L.) plants growing under control conditions. The solutions of hormones prepared at different concentrations (10−4, 10−6, 10−9, 10−12 and 10−15M) were sprayed once on the leaves of 7-day plants. The plants were harvested on 18days after the hormone treatment. Although
all of the hormones at the tested concentrations significantly increased plant growth, soluble protein and sugar contents,
and antioxidant enzyme activities [superoxide dismutase (SOD), peroxidase (POX) and catalase (CAT)], they decreased H2O2 content and lipid peroxidation level when compared with control plants. The activities of SOD, POX and CAT reached to the
highest levels at 10−6M for progesterone, and 10−9M for β-estradiol and androsterone, which maximum growth, protein and sugar contents were determined. The same concentrations
also resulted in the lowest levels for H2O2 content and lipid peroxidation. It can be interpreted that the MSH improve plant growth and development by affecting some
biochemical parameters including antioxidative system.
KeywordsProgesterone–Estradiol–Androsterone–Plant growth–Antioxidant enzyme–Lipid peroxidation–H2O2
The influence of selected animal steroid sex hormones, on generative development of winter wheat var. Grana was investigated. Wheat plants of this variety necessitate 63-day long vernalization.
Mature, isolated embryos of wheat were cultured in vitro on media containing androsterone, androstenedione, estriol, estrone, 17β-estradiol and progesterone in concentrations 10−5 and 10−6 M. They were not vernalized or vernalized for 7, 14, 21 and 28 days (5 °C, 8 h photoperiod).
Investigated steroids stimulated the generative development of winter wheat by an increasing in the percentage of heading
plants and accelerating the heading. The strongest effect was observed when plants were treated with steroids during the suboptimal,
21 and 28 day, vernalization. After 28 days of vernalization, 100 % heading were observed in plants obtained on the media
containing androsterone and androstenedione in concentrations 10−5 and 10−6 M or estrone, 17β-estradiol and progesterone in concentration 10−5 M. Control plants showed only 8 % heading.
It is usually assumed that aquaporins present in the cellular membranes could be an important route in the control of water
flux in plants, but evidence for this hypothesis is scarce. In this paper, we report measurements of the osmotic permeability
(P
os
) of protoplasts isolated from hypocotyls of wild-type and mutant Arabidopsis thaliana (L.) Heynh. Mutants were affected in their growth and exhibited different sensitivities to the phytohormone, brassinolide.
For the two mutants studied (cpd: constitutive photomorphogenesis and dwarfism; bri1: brassinosteroid insensitive), hypocotyl length was correlated to P
os
for the protoplasts. Under experimental conditions where hypocotyl growth had ceased, restoration of root, hypocotyl and
petiole growth by brassinolide was correlated with an increase in P
os
of the hypocotyl protoplasts. We consider that the increase in P
os
of the hypocotyl cells was needed because these cells were part of the transcellular water pathway of the plant. This is
the first time, to our knowledge, that brassinolide has been shown to be involved in the modification of the water-transport
properties of cell membranes. Our results also emphasize the importance of aquaporins and the transcellular pathway in water
transport under normal growth conditions.
The aim of the study has been to determine the protection effect of brassinosteroid (BR27) in oilseed rape cotyledons against infection by an incompatible wild type of, a hypersensitive response mutant of and saprophytic
Pseudomonas bacteria. In this paper, membrane permeability, PSII efficiency and metabolic activity were analysed. The following strains
of Pseudomonans were used: P. syringae pv. syringae (Ps), P. syringae pv. syringae hrcC mutant (Pm) and P.
fluorescence (Pf). The study was carried out using two cultivars of spring oilseed rape (Brassica napus L.): ‘Licosmos’ and ‘Huzar’. Pre-treatment of cotyledons with BR27 caused about 50–70% increase in ion leakage for both cultivars. However, BR27 significantly decreased ion leakage from cotyledons inoculated with Ps in both cultivars. Infection with Ps and Pf caused disturbances of energy flow in PSII by lowering its efficiency in rape cotyledons. We noted insignificant impact of
24-epibrassinolide on PSII efficiency if compared to absolute control, but generally it had a positive effect in plants infected
with bacteria. The values of heat flow in all treatments, except for cotyledons infected with Ps, decreased during 20h after inoculation. However, the curves of heat flow for Ps-infected cotyledons showed a completely different pattern with at least two peaks. BR27 pre-treated cotyledons infected with Ps had higher heat flow in comparison to Ps infected ones. BR27 treatment did not change specific enthalpy of cotyledon growth (Δgh) for both cultivars if compared with absolute control. However, infection with Ps markedly increased Δgh values by about 200% for both cultivars. We suggested protective action of BR27 in oilseed rape cotyledons after bacterial infection with Pseudomonas.
Keywords
Brassica napus
–24-Epibrassinolide–Isothermal calorimetry–Membrane permeability–Pathogenesis–PSII efficiency
Polyhydroxylated steroids are regulators of body shape and size in higher organisms. In metazoans, intracellular receptors recognize these molecules. Plants, however, perceive steroids at membranes, using the membrane-integral receptor kinase BRASSINOSTEROID INSENSITIVE 1 (BRI1). Here we report the structure of the Arabidopsis thaliana BRI1 ligand-binding domain, determined by X-ray diffraction at 2.5 Å resolution. We find a superhelix of 25 twisted leucine-rich repeats (LRRs), an architecture that is strikingly different from the assembly of LRRs in animal Toll-like receptors. A 70-amino-acid island domain between LRRs 21 and 22 folds back into the interior of the superhelix to create a surface pocket for binding the plant hormone brassinolide. Known loss- and gain-of-function mutations map closely to the hormone-binding site. We propose that steroid binding to BRI1 generates a docking platform for a co-receptor that is required for receptor activation. Our findings provide insight into the activation mechanism of this highly expanded family of plant receptors that have essential roles in hormone, developmental and innate immunity signalling.
Brassinosteroids (BRs) are signaling molecules that play essential roles in the spatial regulation of plant growth and development. In contrast to other plant hormones BRs act locally, close to the sites of their synthesis, and thus homeostatic mechanisms must operate at the cellular level to equilibrate BR concentrations. Whilst it is recognized that levels of bioactive BRs are likely adjusted by controlling the relative rates of biosynthesis and by catabolism, few factors, which participate in these regulatory events, have as yet been identified. Previously we have shown that the UDP-glycosyltransferase UGT73C5 of Arabidopsis thaliana catalyzes 23-O-glucosylation of BRs and that glucosylation renders BRs inactive. This study identifies the closest homologue of UGT73C5, UGT73C6, as an enzyme that is also able to glucosylate BRs in planta.
In a candidate gene approach, in which homologues of UGT73C5 were screened for their potential to induce BR deficiency when over-expressed in plants, UGT73C6 was identified as an enzyme that can glucosylate the BRs CS and BL at their 23-O-positions in planta. GUS reporter analysis indicates that UGT73C6 shows over-lapping, but also distinct expression patterns with UGT73C5 and YFP reporter data suggests that at the cellular level, both UGTs localize to the cytoplasm and to the nucleus. A liquid chromatography high-resolution mass spectrometry method for BR metabolite analysis was developed and applied to determine the kinetics of formation and the catabolic fate of BR-23-O-glucosides in wild type and UGT73C5 and UGT73C6 over-expression lines. This approach identified novel BR catabolites, which are considered to be BR-malonylglucosides, and provided first evidence indicating that glucosylation protects BRs from cellular removal. The physiological significance of BR glucosylation, and the possible role of UGT73C6 as a regulatory factor in this process are discussed in light of the results presented.
The present study generates essential knowledge and molecular and biochemical tools, that will allow for the verification of a potential physiological role of UGT73C6 in BR glucosylation and will facilitate the investigation of the functional significance of BR glucoside formation in plants.
In the oviduct, cumulus cells that surround the oocyte release progesterone. In human sperm, progesterone stimulates a Ca(2+) increase by a non-genomic mechanism. The Ca(2+) signal has been proposed to control chemotaxis, hyperactivation and acrosomal exocytosis of sperm. However, the underlying signalling mechanism has remained mysterious. Here we show that progesterone activates the sperm-specific, pH-sensitive CatSper Ca(2+) channel. We found that both progesterone and alkaline pH stimulate a rapid Ca(2+) influx with almost no latency, incompatible with a signalling pathway involving metabotropic receptors and second messengers. The Ca(2+) signals evoked by alkaline pH and progesterone are inhibited by the Ca(v) channel blockers NNC 55-0396 and mibefradil. Patch-clamp recordings from sperm reveal an alkaline-activated current carried by mono- and divalent ions that exhibits all the hallmarks of sperm-specific CatSper Ca(2+) channels. Progesterone substantially enhances the CatSper current. The alkaline- and progesterone-activated CatSper current is inhibited by both drugs. Our results resolve a long-standing controversy over the non-genomic progesterone signalling. In human sperm, either the CatSper channel itself or an associated protein serves as the non-genomic progesterone receptor. The identification of CatSper channel blockers will greatly facilitate the study of Ca(2+) signalling in sperm and help to define further the physiological role of progesterone and CatSper.
Effects of progesterone and beta-estradiol on morphologic (germination velocity, root and shoot length) and biochemical (activities of alpha-amylase, superoxide dismutase, peroxidase and catalase, H2O2 content, lipid peroxidation) parameters during germination and post-germination stages of chickpea seeds were studied. The seeds germinated at various hormone concentrations (10(-4), 10(-9), 10(-9), 10(-12), 10(-15) M) were harvested at the end of the 1st, 3rd, and 5th day. With comparison to the control, these hormones caused an increment in the number of germinating seeds at the end of days 1 and 3 by accelerating the seed germination. Root and shoot lengths were augmented by both hormones at all hormone concentrations tested. The highest elongation was recorded in 10(-6) M progesterone and 10(-9)-10(-12) M beta-estradiol. Similarly, activities of a-amylase and superoxide dismutase were increased by all concentrations of both hormones, and maximum increases were obtained with 10(-6) M progesterone and 10(-1)-10(-12) M beta-estradiol. In the case of superoxide dismutase activity, not only the H2O2 content but also the peroxidase and catalase activities increased. Lipid peroxidation decreased depending on an increase in the antioxidant enzyme activities. In the present study, it was demonstrated that progesterone and beta-estradiol even at low concentrations increase the germination velocity and resistance to stress conditions by changing the activities of some biochemical pathways.
The menstrual cycle is a complex process involving the interaction of the hypothalamus, the anterior pituitary, the ovaries and the uterus. The hormonal changes occurring during this cyclic process not only affect oocyte maturation and the endometrial and vaginal environments but can also have an effect on a number of other physiological and biochemical phenomena.
We investigated the changes in serum calcium, magnesium and inorganic phosphorus levels during different phases of the menstrual cycle in fifty healthy young women. We found subtle but significant variations in these levels in the menstrual, follicular and luteal phases.
The serum calcium level was highest in the follicular phase whereas the serum magnesium level was lowest in the follicular phase; the serum inorganic phosphorus levels was highest in the menstrual phase.
These variations could be due to the impact of the changing estrogen and progesterone secretion on the parathyroid glands.
The presence and location of specific binding sites for progesterone and 17beta-estradiol in cells of wheat were estimated using radioligand binding assay. Membrane and cytosolic fractions of non-vernalized and vernalized plants were tested using tritium-labelled ligands. Specific binding of [(3)H]progesterone and [(3)H]17beta-estradiol occurs in wheat cells. The binding sites are located in membranes and in the cytosol. Specific binding of [(3)H]17beta-estradiol is higher in the membranes than in the cytosol. Specific binding of both ligands in the cytosolic fraction is higher in vernalized plants than in non-vernalized ones. The possibility of the occurrence of steroid binding proteins specific for progesterone and 17beta-estradiol, putative steroid receptors for these steroids in Triticum aestivum L., is discussed.
Self-association of histones H1 from calf thymus and from sperm of the marine worm Chaetopterus variopedatus was studied on native and glutaraldehyde cross-linked molecules by PAGE and by salt-induced turbidity measurements. Multiple polymers were generated by native sperm histone H1-like after glutaraldehyde cross-linking while the same treatment on its lysine- or arginine-modified derivatives and on somatic histone H1 failed to induce polymerization. This result suggests the relevance of arginine content in the formation of histone H1-like polymers particularly because Chaetopterus variopedatus and calf thymus histones H1 have similar content of lysine but different K/R ratio (2 and 15, respectively). Salt-induced turbidity experiments confirmed the high tendency of sperm histone H1-like to form oligomers, particularly in the presence of phosphate ions. Native PAGE analysis in the presence of phosphate supported this hypothesis. The reported results suggest that phosphate ions connecting lysine and arginine side chain groups contribute to the interaction of sperm histone H1-like with DNA in chromatin and play a key role in organization and stabilization of the chromatin higher order structures.
Multiple regulatory mechanisms assure that signal transduction, involving the nuclear receptor interface, results in an accurate regulation of the respective gene networks. These mechanisms involve selective expression of the cognate receptor and its binding to specific hormone response elements of target genes. However, superimposed onto this "simple" control of activity is interpretation of the signal by the multiple functional modules of a given receptor, based on a specific interplay with 1) various factors binding to complex target gene promoters, 2) cell-specific transcription factors that mediate its enhancer function, and 3) other signaling pathways. This interpretation can be further modulated by the differential target gene specificities of receptor isoforms and, according to in vitro evidence, by factors that increase the efficiency of the receptor to interact with its response element. Thus, steroid hormone-regulated gene transcription involves a multitude of interactive elements, as is expected from the central role of nuclear receptors in homeostasis, embryonic development, and differentiation.
Activities of the enzymes cholesterol monooxygenase (side chain cleaving) (SCCE), delta5-3g-hydoxysteroiddehydrogenase / delta5-delta4ketosteroid isomerase (HKI), progesterone 5t-reductase, 3g-hydroxysteroid 5g-oxidoreductase, 3alpha-hydroxysteroid 5B-oxidoreductase, progesterone 5alpha-reductase and 3B-hydroxysteroid 5alpha-oxidoreductase which are involved in biosynthesis and transformation of pregnane derivatives were determined in different developmental stages of somatic embryos of D. lanata. All enzymes were found to be present in proembryogenic masses as well as in globular and bipolar embryos. Most SCCE activity was found in the mitoehondria fraction. Cholesterol, sitosterol and stigmasterol, precursors of the pregnanes, occured in somatic embryos in amounts of about 1 mg / mg protein. Pregnenolone was found in traces only (about 20 ng / mg protein), but in all investigated stages. HKI showed the highest activity in stages which did not produce cardenolides. Feeding of progesterone caused an increase of the contents of 5alpha- and 5t3-pregnandione, progesterone, 5t-pregnane-3alpha-ol,20-one and 5alpha-pregnane-3g-ol-20one in stage-II-globules. In contrast administration of cholesterol caused a small increase of pregnenolone only. These results indicate that the rate limiting step in pregnane (and probably in cardenolide biosynthesis) is compartmentation of SCCE in the mitochondria of the somatic embryos of D. lanata.
Sex hormone-binding globulin (SHBG) is a multifunctional protein that acts in humans to regulate the response to steroids at several junctures. It was originally described as a hepatically secreted protein that is the major binding protein for sex steroids in plasma, thereby regulating the availability of free steroids to hormone-responsive tissues. SHBG also functions as part of a novel steroid-signaling system that is independent of the classical intracellular steroid receptors. Unlike the intracellular steroid receptors that are ligand-activated transcription factors, SHBG mediates androgen and estrogen signaling at the cell membrane by way of cAMP. We have reviewed the current state of knowledge on the SHBG gene and the role of SHBG in steroid signaling (we shall not address its function as a plasma-binding protein).
Metabolisms of both teasterone and its 3-myristate were studied using lily cell cultures. Teasterone was metabolized to two ester conjugates, teasterone-3-myristate and teasterone-3-laurate, which have been identified from the lily pollen. On the other hand, teasterone-3-myristate was metabolized to teasterone. The same reversible conversion was suggested during the course of brassinolide biosynthesis in the lily pollen. It was considered that the conjugates are the reversible storage forms during the biosynthesis of brassinolide.
Progesterone was converted to 5α-pregnanolone palmitate in high yield by tobacco (Nicotiana tabacum var. Bright Yellow) and Sophora angustifolia callus tissues. In Sophora angustifolia callus, 5α-pregnanolone was detected at the same time. The results showed that progesterone undergoes stereospecific reduction of the α,β-unsaturated keto group and esterification. Pregnenolone was also converted to pregnenolone palmitate and 5α-pregnanolone palmitate by tobacco and Sophora angustifolia callus tissues.
I. SUMMARY
The current information regarding the occurrence of steroidal oestrogens and the physiological significance of these compounds in plants is reviewed. Special reference is made to the effects of oestrogens on elongation growth, and results are presented from experiments with Pisum and Phaseolus seedlings.
External application of estradiol-17β increased shoot growth but decreased root growth of sunflower seedlings. It completely inhibited cotyledonary axillary bud development in decapitated plants at the concentration of 1 μg/plant. Concentrations lower than this promoted cotyledonary axillary bud formation. Testosterone on the other hand inhibited both shoot and root growth and promoted cotyledonary axillary bud formation at all the concentrations used. Progesterone at high (0.25,μg/plant) concentration promoted shoot growth but inhibited root growth. A low concentration (0.1 μg/plant) of progesterone produced the opposite effect.
Typical brassinosteroid activity was found in the alkaline hydrolysate of the n-hexane fraction of lily pollen. Two acyl conjugates of teasterone were purified from the n-hexane fraction by HPLC and analyzed by GC-MS and/or LC-MS, resulting in the identification of teasterone esters with laurie acid and myristic acid. Syntheses of the teasterone esters are also reported. The acyl conjugates of typhasterol, castasterone, and brassinolide did not occur in lily pollen. This is the first time that acyl conjugates have ever been discovered among naturally occurring brassinosteroids.
Steroids have been detected in a range of plant species. To investigate the prevalence of four steroids in plants, radioimmunoassay was used to detect the presence of androstenone (boar taint), androgen, estrogen, and progesterone. Androstenone is known only from pigs and humans, but the others are widespread in mammals. A total of 128 species from over 50 families was sampled. All four steroids were widespread, with androstenone and progesterone being found in more than 80% of species, androgen in 70%, and estrogen in 50%. All seed samples contained androgen but none contained androstenone. In three species, androgen was more abundant in male flowers than female flowers, but progesterone and estrogen, when present, were at higher level in female flowers. The function of these steroids in plants is not known.
It has been shown that the cultured cells of Digitalis purpruea are capable of transforming progesterone (I) to 5α-pregnane-3,20-dione (II), 5α-pregnan-3β-ol-20-one (III), its glucoside (IV), 5α-pregnane-3β,20α-diol (V), its glucoside (VI), 5α-pregnane-3β,20β-diol (VII), its glucoside (VIII), Δ4-pregnen-20α-ol-3-one (IX), its glucoside (X), Δ-pregnen-20β-ol-3-one (XI) and its glucoside (XII). 5α-Pregnan-3β-ol-20-one glucoside (IV), 5α-pregnane-3β,20α-diol glucoside (VI), 5α-pregnane-3β,20β-diol glucoside (VIII), Δ4-pregnen-20α-ol-3-one glucoside (X) and Δ4-pregnen-20β-ol-3-one glucoside (XII) have been found for the first time as new metabolises by plant tissue cultures. A scheme for the biotransformation of progesterone (I) has been proposed, and the reduction and glucosidation activities distinctly have been observed in these cultured cells.
Recent studies on chilling tolerance mechanisms in maize revealed a significant positive correlation between genotypic chilling tolerance and chilling-induced accumulation of the stress hormone abscisic acid (ABA) under controlled growth chamber conditions. Based on this and other results, the hypothesis was developed that chilling tolerance in maize is related to the ability to accumulate large amounts of ABA rapidly, as a protection against chilling injury. The objective of the present study was to test this hypothesis under field conditions during natural cold weather periods in spring, which often cause severe chilling injury in maize fields. In two experiments at two locations in Europe with contrasting climates, eight maize genotypes with different genotypic chilling tolerance were cultivated in spring in the field according to agronomic practice for maize. Before and at the end of cold weather periods, ABA levels and water contents were determined in the third leaves. It was found that chilling-tolerant genotypes accumulated higher amounts of ABA during the chilling period than chilling-sensitive genotypes. A significant positive correlation between chilling tolerance and the levels of ABA in the leaves was found. These results support the above-mentioned hypothesis. In contrast to earlier studies performed under growth chamber conditions, the water content in chilled leaves was mostly higher than in non-chilled leaves. The increase in ABA is therefore not attributable to chilling-induced water deficit, but probably to the low temperature itself.
Plasmalemma from 8-day old oat (Avena sativa L. cv. Brighton) and spring wheat (Triticum aestivum L. cv. Drabant), grown in the dark at 18°C, was prepared from the 10000 g (10 min) – 30 000 g (60 min) root homogenate by two-phase separation in three steps with 6.5% (w/w) Dextran T 500 and 6.5% (w/w) polyethylene glycol 4 000. Biochemically and with respect to activation by Mg2+ as well as by (Mg2++ K+), the oat preparations clearly appeared as ATPase(s) in the pH range 5–8. They showed high specificity for ATP, temperature optima between 38 and 40°C, and were inhibited by vanadate, DCCD (dicyclohexylcarbodiimide) and SH-reagents, but not by oligomycin, ammonium molybdate or ouabain. In contrast, the preparations from wheat contained more than one type of MgATPase/ nucleotidase, as revealed by complex dependence on both pH and temperature as well as by comparatively low specificity towards nucleotides. However, no unspecific phosphatase was present, and the effect of K+ over and above that of Mg2+ was almost as specific as in oat by all criteria used. The data available from this and earlier investigations from our group would indicate that the complex reactions of preparations of wheat plasmalemma may not be due to contamination but, rather, expressions of the many biological functions that must be associated with the plasmalemma in vivo and which may be located in sub-units that are more firmly attached to wheat than to oat plasmalemma.
Dioscorea deltoidea plant tissue suspension cultures are capable of metabolizing progesterone to 5α-pregnan-3-β-ol-20-one and 5α-pregnan-3β,20β-diol. The latter product has not previously been reported as a metabolic product of progesterone by plant systems. Both transformation products are present as conjugates in this plant tissue culture.
SummaryA hypothesis developed in two earlier papers (Capell and Dörffling 1993, Janowiak and Dörffling 1996), but critically reinvestigated recently by Ristic et al. 1998 was tested again with new material and methods. According to the hypothesis, chilling tolerant maize genotypes accumulate abscisic acid (ABA) faster and in higher amounts than chilling sensitive genotypes when exposed to chilling stress. This relationship is in accordance with a suggested protective role of ABA against chilling injury. The hypothesis was tested in two ways: first by investigating 20 new maize genotypes with defined differences in chilling tolerance, second by manipulating the endogenous level of ABA during a low temperature treatment by applying the ABA biosynthesis inhibitor norflurazon and measuring the resulting chilling tolerance.Results of the first approach showed that the accumulation of ABA in the third leaves determined by an indirect ELISA after two days of chilling at 4 °C was significantly correlated with chilling tolerance as measured by necrotic injury and by ϕPSII of the 20 tested genotypes. Accumulation of ABA induced by low temperature was significantly higher in the group of chilling tolerant genotypes than in that of chilling sensitive ones. It was inversely related to chilling-induced water loss.Results of the second experiment showed that norflurazon-treated seedlings were less chilling tolerant and accumulated less ABA than untreated ones. Application of ABA compensated the reduction in chilling tolerance by norflurazon.It is concluded that the results support the above mentioned hypothesis that chilling tolerance in maize is related to the ability to accumulate ABA as a protective agent against chilling injury.
Brassinosteroids are plant steroid hormones important for plant growth and development. They include more then 70 compounds. Their physiological effect and possibilities of practical use are still being investigated. In this study, we evaluated the effects of exogenously applied 24-epibrassinolide, one of the brassinosteroids, on the grain yield and grain chemical composition (carbohydrates, proteins, fats and minerals) of wheat. Moreover, we analysed the presence of brassinosteroids in newly formed wheat grains after exogenous plant treatment with 24-epibrassinolide. Experiments were performed in a vegetation hall (plants cultivated in pots) and in the field. The tested regulator was applied via 48 h seed soaking (1 mg·dm−3) or spraying plants at the heading stage (0.25 mg·dm−3). 24-epibrassinolide increased grain yield in plants growing in the field (by about 20 %), but not in plants cultivated in vegetation hall. Grain chemical composition was altered by 24-epibrassinolide in wheat growing in the vegetation hall; the content of soluble sugars was higher while that of total fats and calcium was lowered, whereas the starch and soluble protein content was not affected. The effect of the hormone was in these cases dependent on the method of its application. As for plants cultivated in the field, the hormone impact on the amount of carbohydrates, proteins, fats and minerals contained in the grains was rather negligible. In wheat grains, the presence of brassinolide, castasterone and 24-epicastasterone was found. 24-Epibrassinolide applied exogenously to plants was not accumulated in newly formed grains. Additionally, significance of ethanol as a hormone solvent is discussed.
The influence of selected steroids on the in vitro generative development of Arabidopsis thalianawas investigated. The activity of the animal steroids androsterone, androstenedione, progesterone, estrone, estriol, and 17-estradiol was compared to 24-epibrassinolide, a member of the regulatory family of brassinosteroids. A. thaliana plants were cultured in vitro in media containing these steroids. The stimulatory effect of the tested substances was evaluated by measurement of the percentage of generative plants versus vegetative plants in the experimental group. It was established that androstenedione, the main testosterone precursor, and androsterone, a typical male hormone, were more effective in stimulating flowering in A. thaliana than the female hormones, estrogens and progesterone. Androsterone at a concentration of 0.1 M increased the percentage of generative plants up to 96% (control 41%). Estrogens at the same concentration decreased the number of generative plants and 24-epibrassinolide did not stimulate A. thalianagenerative development.
We have developed an effective method for the isolation, identification, and quantification of several mammalian steroid hormones
and their metabolites in different plant tissues. The purification protocol was based on solid-phase extraction (SPE) combined
with immunoaffinity chromatography (IAC) using immobilized generic polyclonal anti-Δ4-3-keto-steroid antibodies covalently bound to Affi-Gel 10 sorbent. The antibodies were characterized by means of enzyme-linked
immunosorbent assay (ELISA). The detection limit of the ELISA was 6.0×10−10mol L−1 and cross-reactivity with most Δ4-3-keto-steroids was very high as predicted (68–122%). The IAC allowed fast, single-step purification of different plant extracts
prior to analysis by ultra-performance liquid chromatography-electrospray tandem mass spectrometry [UPLC-ESI(+)-MS/MS]. In
multiple-reaction-monitoring (MRM) mode, the detection limit of the method for most of the steroids analyzed was close to
10fmol and the response was linear up to 50pmol injected. The analytical accuracy was validated using tobacco leaf samples
spiked with known amounts of authentic and deuterium-labeled standards. The newly developed method was capable of detecting
and quantifying at least 12 specified steroid compounds in plant extracts. In the analyzed extracts from three plant species,
that is, common foxglove (Digitalis purpurea L.), tobacco (Nicotiana tabacum L.), and elecampane inula (Inula helenium L.), four endogenous steroids were detected, identified, and quantified. Progesterone was found in all three plants at concentrations
comparable to those reported in previous studies. Three other steroids, androstendione, 17α-hydroxyprogesterone, and 16-dehydroprogesterone,
were identified for the first time in plant extracts. 17α-Hydroxyprogesterone and 16-dehydroprogesterone occurred at significant
concentrations in D. purpurea, whereas androstendione was found in N. tabacum and I. helenium but not in D. purpurea.
The natural occurrence of the sex steroid hormones progesterone, testosterone, 17β-estradiol and estrone in food was investigated in a survey of the German market basket. The main metabolic precursors, intermediates and metabolites (pregnenolone, androstenedione, hydroxyprogesterone, dehydroepiandrosterone (DHEA), dihydrotestosterone, androsterone, 17α-estradiol and estriol) were also included in the investigation. Particular attention was paid to DHEA, which is said to have anti-aging properties. Analysis was carried out by gas chromato-graphy-mass spectrometry (GC-MS). The steroid patterns of pork, meat products, fish and poultry resemble those known for beef. Milk and milk products reflect the hormone profile of female cattle with high amounts of progesterone, which accumulates with increasing milk fat content. Milk products supply about 60–80% of ingested female sex steroids. Eggs are a considerable source of any of the investigated steroids and contribute to the nutritional hormone intake in the same order as meat and fish (10–20%). In vegetable food no estrogens could be detected. Plants supply testosterone in the same order as meat and milk products (20–40%) though. They contain considerable amounts of hormone precursors as well (contribution to DHEA supply: about 80%). In comparison to the human daily production of steroid hormones the nutritional supply (about 10 μgd−1 progesterone, 0.05 μg d−1 testosterone, 0.1 μg d−1 estrogens, 0.5 μg d−1 DHEA) is insignificant.
The synthesis of steroid hormones in different plant species and the possibility that these molecules could regulate cell growth, tissue differentiation and germination has been reported. However, the mechanism of action of these endogenous steroids in plant cells is still poorly understood. In the present work, binding experiments with [3H]17β-estradiol in the presence and absence of an excess of unlabeled 17β-estradiol showed that Solanum glaucophyllum and Lycopersicon esculentum organs contain estrogen-binding sites. Scatchard analysis detected saturable [3H]17β-estradiol-binding sites (Kd∼6.6 nM; Bmax∼1140 fmol/mg protein) in S. glaucophyllum callus tissue. Estrogen-like compounds were detected in lipid extracts from S. glaucophyllum and L. esculentum. Moreover, the lipid fraction was able to compete with [3H]17β-estradiol for binding to estrogen receptor (ER) from breast cancer MCF-7 cells as well as with estrogen-binding sites present in both plant species. Western blot analysis with monoclonal antibodies against different domains of the ER α, detected a ∼67 kDa band in various organs of both plant species. These proteins were able to bind estradiol in ligand blot assays using 17β-estradiol macromolecular derivatives as ligands. Western and ligand blot experiments of subcellular fractions from callus tissues of S. glaucophyllum showed that the ER-like protein of ∼67 kDa was most concentrated in the nuclear fraction. Reactive bands of lower molecular weight were also detected. Altogether these results provide evidence about the existence of estrogen-binding proteins and endogenous ligands in Solanaceae.
Brassinosteroids are found in a wide range of organisms from lower to higher plants. They are steroidal plant hormones implicated in the promotion of plant growth and development. Brassinosteroid metabolism has long been known to be altered in plants responding to abiotic stresses and to undergo profound changes in plants interacting with bacterial, fungal and viral pathogens. This review describes the role of brassinosteroids in response to various kinds of stresses via activation of different mechanisms.
This study aimed to investigate the influence of progesterone, a mammalian sex hormone, on germination of bean (Phaseolus vulgaris L.) seeds exposed to salt stress. The exogenous addition of 10(-6), 10(-8) and 10(-10) M progesterone to the stressing media in which bean seeds were germinated in combination with the salt (100 mM NaCl) stressor induced significant protective changes in the germination and early growth parameters. The mitigating effect of progesterone was evaluated by the measurement of radicle and plumule lengths, activities of antioxidant enzymes superoxide dismutase (SOD), peroxidase (POX) and catalase (CAT). In addition, it is the first study that exhibited changes in K/Na ratio. The obtained results showed that progesterone application stimulated germination and growth of salt-stressed seeds. Similarly, it stimulated significantly SOD, POX and CAT activities compared to both control and salt control. Salt stress significantly increased the lipid peroxidation compared to the control seeds. However, parallel to the increase in antioxidant activity, lipid peroxidation was significantly reduced by progesterone application. The best stimulatory effects on investigated parameters were recorded at 10(-8) M progesterone-applied seeds. On the other hand, salt stress reduced remarkably K/Na ratio by 50% in radicle and by 80% in plumule. However, progesterone application significantly mitigated the reduction in K/Na ratio. These findings clearly demonstrate that progesterone has a positive role in moderate detrimental effects induced by salt.
Activities of the enzymes cholesterol monooxygenase (side chain cleaving) (SCCE) isomerase, progesterone 5β-reductase, 3β-hydroxysteroid 5β-oxidoreductase, 3α-hydroxysteroid 5β-oxidoreductase, progesterone 5α-reductase and 3β-hydroxysteroid 5α-oxidoreductase which are involved in biosynthesis and transformation of pregnane derivatives were determined in different developmental stages of somatic embryos of Digitalis lanata. All enzymes were found to be present in proembryogenic masses (PEMs) as well as in globular and bipolar embryos. Most SCCE activity was found in the mitochondria fraction. Cholesterol, sitosterol and stigmasterol, precursors of the pregnanes, occurred in somatic embryos in amounts of about 1 μg mg−1 protein. Pregnenolone was found in traces only (about 20 ng mg−1 protein). Feeding of progesterone caused an increase of the contents of 5α-pand 5β-pregnandione, progesterone, 5β-pregnane-3α-ol,20-one and 5α-pregnane-3β-ol,-20-one. In contrast, administration of cholesterol caused a small increase of pregnenolone only. These results indicate that the rate limiting step in pregnane (and probably in cardenolide biosynthesis) is compartmentation of CSSE in the mitochondria of the somatic embryos of D. lanata.
Salinity is one of the most serious constraints facing agriculture today. Some mechanical, chemical and biological approaches are being pursued to cope with soil salinity. Although exogenously treated mammalian sex hormones (MSHs), progesterone, β-estradiol and androsterone, activate significant effects in various biological aspects in plants growing under normal conditions, there is no report investigating their effects on plants growing under salt stress. The present study aimed to investigate whether MSHs could alleviate the destructive effect of salt stress on wheat seedlings and thereby increase their salt tolerance. Wheat leaves were sprayed with 10(-6), 10(-8) and 10(-10) mol L(-1) concentrations of MSH on the ninth day after sowing. MSH-treated seedlings (10-day-old seedlings) were subjected to salt stress for 5 days (between days 10 and 15).
At all the concentrations tested, MSH treatment provided a significant protection against to detrimental effects of salt stress in wheat seedlings. It improved dry weight, sugar, proline, protein, chlorophyll and glutathione contents in comparison to salinity alone. Similarly, superoxide dismutase, peroxidase, catalase, ascorbate peroxidase and nitrate reductase activities also were augmented by MSH treatment. On the other hand, increases in lipid peroxidation level, superoxide production and hydrogen peroxide content arising from salt treatment were reduced by MSH treatment. The highest salt tolerance was obtained at the concentrations of 10(-6) mol L(-1) for progesterone and 10(-8) mol L(-1) for β-estradiol and for androsterone.
MSHs could be used effectively to protect wheat seedlings from the destructive effects of salt stress by stimulating both enzymatic and non-enzymatic antioxidant mechanism and by promoting levels of osmotic protectants such as proline and sugars resulting in osmotic adjustment, carbon storage and radical scavenging in plants.
Steroids are present in living organisms as one of the most essential groups of compounds. Continuous research has led to new discoveries and the revision of existing information concerning the occurrence and the role of steroids, both in animals and plants. This article will focus on reviewing the literature studying progesterone in the plant kingdom, including its discovery, its occurrence in different plant species as well as its biological activity and molecular basis of action. This review will present and discuss the current data in addition to introducing potential directions for further research on the subject of progesterone in plants.
BACKROUND: Mammalian sex hormones (MSH)—progesterone, β-estradiol and androsterone—enhance plant growth and development by stimulating significant morphological and biochemical parameters under normal conditions. However, there is no report regarding their effects on plants exposed to environmental stress conditions. Therefore, the present study was focused on elucidating the possible positive effects of MSH on seedling growth, antioxidant activity and synthesis reactions in maize seeds exposed to salt stress, one of the most important environmental stresses. For this purpose, the various concentrations (10−6, 10−8, 10−10 and 10−12 mol L−1) of MSH were studied.
RESULTS: Salinity (100 mmol L−1 NaCl) significantly reduced root length and seedling height, whereas MSH treatment significantly ameliorated the adverse effects of salinity on root length and seedling height. On the other hand, although salinity increased soluble protein, soluble sugar and proline content in 7-day-old maize seedlings, these were higher in MSH-treated seedlings. Similarly, MSH treatment augmented superoxide dismutase, peroxidase and catalase activities under salt stress, whereas it decreased superoxide production and lipid peroxidation level. The most favorable concentrations were determined as 10−8 mol L−1 for progesterone and β-estradiol and 10−10 mol L−1 for androsterone.
CONCLUSION: Exogenous MSH application was found to have an important ameliorative effect on growth of seeds exposed to salt stress by stimulating antioxidant activity and synthesis reactions. This is the first study investigating the effects of MSH on germination of seeds exposed to stress conditions. Copyright
Brassinosteroids are essential phytohormones that have crucial roles in plant growth and development. Perception of brassinosteroids requires an active complex of BRASSINOSTEROID-INSENSITIVE 1 (BRI1) and BRI1-ASSOCIATED KINASE 1 (BAK1). Recognized by the extracellular leucine-rich repeat (LRR) domain of BRI1, brassinosteroids induce a phosphorylation-mediated cascade to regulate gene expression. Here we present the crystal structures of BRI1(LRR) in free and brassinolide-bound forms. BRI1(LRR) exists as a monomer in crystals and solution independent of brassinolide. It comprises a helical solenoid structure that accommodates a separate insertion domain at its concave surface. Sandwiched between them, brassinolide binds to a hydrophobicity-dominating surface groove on BRI1(LRR). Brassinolide recognition by BRI1(LRR) is through an induced-fit mechanism involving stabilization of two interdomain loops that creates a pronounced non-polar surface groove for the hormone binding. Together, our results define the molecular mechanisms by which BRI1 recognizes brassinosteroids and provide insight into brassinosteroid-induced BRI1 activation.
Brassinosteroid (BR) signal transduction research has progressed rapidly from the initial discovery of the BR receptor to a complete definition of the basic molecular components required to relay the BR signal from perception by receptor kinases at the cell surface to activation of a small family of transcription factors that regulate the expression of more than a thousand genes in a BR-dependent manner. These mechanistic advances have helped answer the intriguing question of how a single molecule, such as a hormone, can have dramatic pleiotropic effects on a broad range of diverse developmental pathways and have shed light on how BRs interact with other plant hormones and environmental cues to shape the growth of the whole plant. This review summarizes the current state of BR signal transduction research and then examines recent articles uncovering gene regulatory networks through which BR influences both vegetative and reproductive development.
Previously, the presence of a wide variety of chemically diverse steroids has been identified in both flora and fauna. Despite the relatively small differences in chemical structures and large differences in physiological function of steroids, new discoveries indicate that plants and animals are more closely related than previously thought. In this regard, the present study gathers supporting evidence for shared phylogenetic roots of structurally similar steroids produced by these two eukaryotic taxa. Definitive proof for the presence of progesterone (3) in a vascular plant, Juglans regia, is provided. Additional evidence is gleaned from the characterization of five new plant steroids from Adonis aleppica: three 3-O-sulfated pregnenolones (6a/ b, 7), a sulfated H-5beta cardenolide, strophanthidin-3-O-sulfate (8), and spirophanthigenin (10), a novel C-18 oxygenated spirocyclic derivative of strophanthidin. The ab initio isolation and structure elucidation (NMR, MS) of these genuine minor plant steroids offers information on preparative metabolomic profiling at the ppm level and provides striking evidence for the conserved structural space of pregnanes and its congeners across the phylogenetic tree.
The concentration of specific progesterone-binding sites in myometrial eytosol from 25 normal menstruating women was measured. Estradiol-17β and progesterone concentrations in the uterine cytosol and peripheral plasma of these patients were also determined by radioimmunoassay. The specific progesterone-binding capacity ranged from 63 to 722 fmol/mg of myometrial cytosolic protein (mean 335 ± 181 fmol/mg protein) with an equilibrium association constant of 4.2 ± 1.3 × 109 1/mol. Density gradient centrifugation showed that [3H]-progesterone was bound to a macromolecule with a sedimentation rate of 3.6 ± 0.3 S.The concentration of cytosolic progesterone-binding sites was inversely correlated to both the plasma and myometrial cytosol progesterone levels. There was also a direct correlation between the concentration of progesterone-binding sites and cytosol estradiol-17β levels. Progesterone binding showed no correlation with plasma estradiol-17β levels. The highest progesterone-binding capacity was found in myometrial cytosol during the late proliferative phase of the menstrual cycle.
Cholesterol and progesterone were identified in apple seeds by the use of thin-layer and gas chromatography and the derivatives of the hormones. The analyses per 100 grams of apple seeds revealed an average of 385.0 μgrams of cholesterol and 50.0 μgrams of progesterone.
In an attempt to understand the mechanism of the antiprogestational action of estrogens during early pseudopregnancy we determined the cytosolic and nuclear concentrations of progesterone receptors in the endometrium of rabbits treated with hCG followed by various combinations of estradiol and progesterone. The progestational response of the endometrium was followed by quantitation of the uteroglobin content in the uterine lumen. In rabbits treated with hCG alone there was a clear progestational response (40% relative uteroglobin content), but only 16% of the progesterone receptors were located in the nucleus. After additional treatment with progesterone the progestational response remained high (45% relative uteroglobin content), the total cellular content of progesterone receptor increased, and 5% of the complexes were found in the nucleus. These findings suggest that a consumption of nuclear progesterone receptor is required for progestational action. Treatment of pseudopregnant rabbits with estradiol resulted in a marked increase not only of the total cellular progesterone receptor but also of the percentage of it located in the nucleus (35%). Concomitantly, the progestational response was markedly inhibited (5% relative uteroglobin content). These results confirm the relevance of nuclear consumption of progesterone receptor for progestational action, and suggest that some antiprogestational effects of estrogens may be due to their interference with the mechanism of progesterone receptor processing.