Plant Cell Reports (PLANT CELL REP)

Publications in this journal

• Article: Influence of stress hormones on auxin homeostasis in Brassica rapa seedlings

  Salopek-Sondi, Šamec, Mihaljević, Smolko, Pavlović, Janković, Ludwig-Müller
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  ABSTRACT: The influence of stress hormones: jasmonic acid (JA), salicylic acid (SA), and abscisic acid (ABA) on 1-day-old seedlings of Chinese cabbage (Brassica rapa L. ssp. pekinensis) was investigated with particular focus on auxin levels and the regulation of reversible auxin conjugation as a mechanism of auxin homeostasis. At the physiological level stress hormones inhibited root growth, where JA was the most prominent inhibitor with an IC50 value 3.1 μM, which is one and two orders of magnitude lower than that found for ABA and SA, respectively. JA treatment significantly increased the total auxin content, by induction of free and conjugated forms. Also, the stress hormones affected the transcription of genes involved in the process of the reversible auxin conjugation: auxin amidohydrolases BrIAR3 and BrILL2, and auxin conjugate synthetases BrGH3.1 and BrGH3.9. JA treatment increased the transcript level of BrIAR3 two-fold, while it did not affect the transcription of BrILL2. SA and ABA down-regulated the transcription of both auxin amidohydrolase genes by 30%. Transcription of both auxin conjugate synthetases was significantly down-regulated by all treatments by 30-70%. Among the investigated biochemical stress markers, glutathione along with protein carbonylation appeared the most affected upon treatments. The redox status of the seedlings was shifted to the more oxidized state upon JA and ABA treatments, whereas SA caused more reduced redox state in comparison to the control. The principal component analysis (PCA) visualized relationship among auxin and stress parameters upon treatments. Accordingly, the role of auxin in stress response of Brassica seedlings was discussed.
  Plant Cell Reports 03/2013;
• Article: Subhash K, Venkataiah P and Bhaskar P (1996) Induction of streptomycin-resistant plantlets in Capsicum annuum L. through mutagenesis in vitro. Plant Cell Reports. 16: 111-113 (I.F: 2.274).

  Subhash K, Venkataiah P and Bhaskar P
  Plant Cell Reports 02/2013; 16:111-113.
• Article: RETRACTED ARTICLE: Transgenic ramie [Boehmeria nivea (L.) Gaud.]: factors affecting the efficiency of Agrobacteriumtumefaciens-mediated transformation and regeneration

  Bo Wang, Lijun Liu, Xuxia Wang, Jinyu Yang, Zhenxia Sun, Na Zhang, Shimei Gao, Xiulong Xing, Dingxiang Peng
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  ABSTRACT: In the present study, an efficient Agrobacterium-mediated gene transformation system was developed for ramie [Boehmeria nivea (L.) Gaud.] based on the examinations of several factors affecting plant transformation efficiency. The effects of Agrobacterium cell density, acetosyringone, co-cultivation temperature, co-cultivation duration, co-cultivation photoperiod and pH on stable transformation were evaluated. Agrobacterium at a concentration of OD=0.5–0.8 improved the efficiency of transformation. Concentration of acetosyringone at 50mg/L during co-cultivation significantly increased transformation efficiency. Co-cultivation at 20°C, in comparison to 15, 25 and 28°C, consistently resulted in higher transformation frequencies. A relatively short co-cultivation duration (3days) was optimal for ramie transformation. Co-cultivation medium at pH 5.9 and co-cultivation in darkness both improved the transformation efficiencies of ramie. An overall scheme for producing transgenic ramie is presented, through which an average transformation rate from 10.5 to 24.7% in five ramie varieties was obtained. Stable expression and integration of the transgenes were confirmed by histochemical GUS assay, kanamycin painting assay, PCR and Southern blotting. This optimized transformation system should be employed for efficient Agrobacterium-mediated transformation of ramie.
  Plant Cell Reports 05/2012; 28(9):1319-1327.
• Article: ArabidopsisACA7, encoding a putative auto-regulated Ca2+-ATPase, is required for normal pollen development

  Noel Lucca, Gabriel León
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  ABSTRACT: Microgametogenesis is a complex process that involves numerous well-coordinated cell activities, ending with the production of pollen grains. Pollen development has been studied at the cytological level in Arabidopsis and other plant species, where its temporal time course has been defined. However, the molecular mechanism underlying this process is still unclear, since a relative small number of genes and/or processes have been identified as essential for pollen development. We have designed a methodology to select candidate genes for functional analysis, based on transcriptomic data obtained from different stages of pollen development. From our analyses, we selected At2g22950 as a candidate gene; this gene encodes a protein belonging to the auto-regulated Ca2+-ATPase family, ACA7. Microarray data indicate that ACA7 is expressed exclusively in developing pollen grains, with the highest level of mRNA at the time of the second pollen mitosis. Our RT-PCR experiments showed that ACA7 mRNA is detected exclusively in developing flowers. Confocal microscopy experiments showed a plasma membrane localization for the recombinant GFP:ACA7 protein. We identified two different insertional mutant lines, aca7-1 and aca7-2; plants from both mutant lines displayed a normal vegetative development but showed large amounts of dead pollen grains in mature flowers assayed by Alexander’s staining. Histological analysis indicated that abnormalities are detected after the first pollen mitosis and we found a strong correlation between ACA7 mRNA accumulation and the severity of the phenotype. Our results indicate that ACA7 is a plasma membrane protein that has an important role during pollen development, possibly through regulation of Ca2+ homeostasis. KeywordsPollen development–ACA7– Arabidopsis
  Plant Cell Reports 04/2012; 31(4):651-659.
• Article: Molecular characterization of ScTFIIAγ, encoding the putative TFIIA small subunit from sugarcane

  Agustina Gentile, Pedro Da Cruz, Rafael G. Tavares, Maria Graziela Krug-Baldacin, Marcelo Menossi
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  ABSTRACT: Transcription mediated by RNA polymerase II depends on a set of different transcription factors to form the pre-initiation complex. TFIIA is involved in the construction of this complex and increases the affinity of TBP for the DNA union region in vitro. In this study, we characterized the ScTFIIAγ gene, which encodes a homolog of the smaller subunit (γ) of transcription factor TFIIA in sugarcane. RNA blot analysis showed that ScTFIIAγ transcripts accumulate in all tissues evaluated, with higher levels in leaf roll and flowers. In situ hybridization showed that ScTFIIAγ was expressed in different cells of the reproductive meristem. In sugarcane plantlets, methyl jasmonate and absicic acid treatments as well as phosphate starvation had no influence on ScTFIIAγ transcript accumulation. The subcelullar localization assay demonstrates that ScTFIIAγ protein is directed to the cell nucleus. The phylogenetic analysis, the expression in several tissues and under different treatments and the nuclear localization are in line with the putative role of ScTFIIAγ as a subunit of basal transcription factor. KeywordsScTFIIAγ -Sugarcane-Transcription factor-In situ hybridization-GFP
  Plant Cell Reports 04/2012; 29(8):857-864.
• Article: Transformation of different barley (Hordeum vulgare L.) cultivars by Agrobacterium tumefaciens infection of in vitro cultured ovules

  Inger Bæksted Holme, Henrik Brinch-Pedersen, Mette Lange, Preben Bach Holm
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  ABSTRACT: Most cultivars of higher plants display poor regeneration capacity of explants due to yet unknown genotypic determined mechanisms. This implies that technologies such as transformation often are restricted to model cultivars with good tissue characteristics. In the present paper, we add further evidence to our previous hypothesis that regeneration from young barley embryos derived from in vitro-cultured ovules is genotype independent. We investigated the ovule culture ability of four cultivars Femina, Salome, Corniche and Alexis, known to have poor response in other types of tissue culture, and compared that to the data for the model cultivar, Golden Promise. Subsequently, we analyzed the transformation efficiencies of the four cultivars using the protocol for Agrobacterium infection of ovules, previously developed for Golden Promise. Agrobacterium tumefaciens strain AGL0, carrying the binary vector pVec8-GFP harboring a hygromycin resistance gene and the green fluorescence protein (GFP) gene, was used for transformation. The results strongly indicate that the tissue culture response level in ovule culture is genotype independent. However, we did observe differences between cultivars with respect to frequencies of GFP-expressing embryos and frequencies of regeneration from the GFP-expressing embryos under hygromycin selection. The final frequencies of transformed plants per ovule were lower for the four cultivars than that for Golden Promise but the differences were not statistically significant. We conclude that ovule culture transformation can be used successfully to transform cultivars other than Golden Promise. Similar to that observed for Golden Promise, the ovule culture technique allows for the rapid and direct generation of high quality transgenic plants.
  Plant Cell Reports 04/2012; 27(12):1833-1840.
• Article: Development of male gametophyte of Larixleptolepis Gord. with emphasis on diffuse stage of meiosis

  Shou-Gong Zhang, Wen-Hua Yang, Yu-Chen Qi, Mao-Xue Li, Jian-Hua Wang, Xiao-Mei Sun, Xiao-Shan Wang, Li-Wang Qi
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  ABSTRACT: A basic developmental framework of the Larix leptolepis Gord male gametophyte is presented in detail by squashing technique. The duration of the meiosis stage was more than 6months, and included a long diffuse stage during winter. This long duration of the diffuse appearance of the diplotene stage makes L. leptolepis a unique suitable experimental material for studying the structure and function of the diffuse stage of meiosis. In particular, the processes of desynapsing and unpairing, which so far have received little attention, can be examined in detail. In L. leptolepis, the chromosomes undergo a dramatic structural reorganization during the diffuse diplotene stage. Based on the clearly visible differences in chromosome morphology, the diffuse diplotene stage was divided into four periods with suggested nomenclature as follows: schizonema, pre-diffuse diplotene, diffuse diplotene and post-diffuse diplotene. Both simultaneous and successive microsporogenesis were observed within L. leptolepis, and there was no strict relationship between the microsporogenesis types and the tetrad configurations, which are strongly influenced by spindle orientation, especially during meiosis II. The mature pollen grain at pollination consists of five cells aligned in an axial row. The prothallial cells cannot be regarded as senescent cells because they remain capable of division.
  Plant Cell Reports 04/2012; 27(11):1687-1696.
• Article: Improved drought and salt tolerance of Arabidopsisthaliana by transgenic expression of a novel DREB gene from Leymuschinensis

  Peng Xianjun, Ma Xingyong, Fan Weihong, Su Man, Cheng Liqin, Iftekhar Alam, Byung-Hyun Lee, Qi Dongmei, Shen Shihua, Liu Gongshe
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  ABSTRACT: Dehydration-responsive element-binding (DREB) proteins are important transcription factors in plant stress responses and signal transduction. Based on high-throughput sequencing results, a new cDNA sequence encoding an LcDREB3a transcription factor from the drought-resistant forage grass, Leymus chinensis, was isolated by RACE PCR. Sequence similarity analysis indicates that the gene product is active in the ABA-responsive pathway, and real-time PCR-based expression analysis shows the transcript accumulates in response to a variety of stress treatments. These results indicate that LcDREB3a is involved in both ABA-dependent and -independent signal transduction in the stress-responsive process of L. chinensis. The identity of the gene product as a DREB transcription factor is supported by observations of its nuclear localization when transiently expressed as a GFP fusion in onion epidermal cells. Furthermore, LcDREB3a is able to activate reporter gene expression, and the protein is shown to specifically bind to the conserved DRE element in a yeast one-hybrid assay. The transgenic expression of LcDREB3a in Arabidopsis causes no growth retardation and induces the increased expression of stress tolerance genes compared to control, resulting in improved drought and salt stress tolerance. Thus, LcDREB3a, encoding a stress-inducible DREB transcription factor, could enhance the abiotic stress tolerance of plants. KeywordsAbiotic stress–ABA responsive– S-adenosylmethionine decarboxylase–Spermidine–Spermine
  Plant Cell Reports 04/2012; 30(8):1493-1502.
• Article: Selectable marker elimination in the T0 generation by Agrobacterium-mediated co-transformation involving Mungbean yellow mosaic virusTrAP as a non-conditional negative selectable marker and bar for transient positive selection

  Mangu Venkata RamanaRao, Karuppannan Veluthambi
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  ABSTRACT: Transient selection involving the bar gene and non-conditional negative selection against stable T-DNA integration through the use of the Mungbean yellow mosaic virus (MYMV) transcriptional activator protein gene (TrAP) were used in a novel co-transformation strategy to generate selectable marker gene (SMG)-eliminated transgenic tobacco plants in the T0 generation itself. Two compatible binary plasmids, pCam-bar-TrAP-gus harbouring bar as an SMG and the MYMV TrAP gene as a non-conditional negative selectable marker, and pGA472 with the nptII gene as an unselected experimental gene of interest (GOI) were placed in the Agrobacterium tumefaciens strain EHA105 and used for co-transformation. Transient selection with 5mgl−1 phosphinothricin (PPT) for 2–4weeks and subsequent establishment in a PPT-minus medium yielded 114 plants from 200 leaf discs. The unselected nptII gene was detected by Southern blot analysis in 13 plants, revealing a co-transformation efficiency of 11.5%. Five of these plants harboured only the nptII gene (GOI) and not the bar gene (SMG). Thus, SMG elimination was achieved in the T0 generation itself in 4.4% (5/114) of plants, which were transiently selected for 2–4weeks on PPT. MYMV TrAP, a non-conditional negative selectable marker, effectively reduced the recovery of plants with stable integration of the SMG (bar). KeywordsCompatible binary vectors-Co-transformation-Marker-free transgenic plants-Non-conditional negative selectable marker-Transient selection
  Plant Cell Reports 04/2012; 29(5):473-483.
• Article: Elevated H2O2 production via overexpression of a chloroplastic Cu/ZnSOD gene of lily (Lilium oriental hybrid ‘Marco Polo’) triggers ethylene synthesis in transgenic potato

  Yoon-Sik Kim, Hyun-Soon Kim, Yong-Hwa Lee, Mi-Sun Kim, Hyun-Woo Oh, Kyu-Woong Hahn, Hyouk Joung, Jae-Heung Jeon
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  ABSTRACT: Transgenic potato plants (SS2 and SS4) that overexpressed a chloroplastic copper/zinc superoxide dismutase lily gene were utilized as an H2O2-inducible system in order to study the role of H2O2 as a signaling molecule in the biosynthesis of ethylene. SS2 and SS4 plants grown in vitro under sealed microenvironment (SME) conditions displayed anomalous phenotypes including reduction of stem elongation, radial stem growth, and promotion of root hair formation in the generated root, which were similar to ethylene-induced responses. In addition, SS4 plants showed severe vitrification in developing leaves and elevated ethylene production under SME conditions. After the ethylene action inhibitor AgNO3, 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase (ACO) inhibitor CoCl2, and ACC synthase inhibitor l-aminoethoxyvinylglycine were added to the growth media, the anomalous phenotypes in SS4 plants reverted to their normal phenotype with a concurrent decrease in ethylene production. Northern blot analysis showed that ACO transcripts in SS4 plants were constantly at high levels under normal and SME conditions, indicating that a high level of H2O2 in SS4 plants up-regulates ACO transcripts. Moreover, the direct treatment of H2O2 in potato plants confirmed the elevated expression of the ACO gene. Taken together, these data suggest that the high concentration of H2O2 in transgenic potato plants stimulates ethylene biosynthesis by activating ACO gene expression.
  Plant Cell Reports 04/2012; 27(6):973-983.
• Article: Enhancement of tolerance to soft rot disease in the transgenic Chinese cabbage (Brassica rapa L. ssp. pekinensis) inbred line, Kenshin

  Enkhchimeg Vanjildorj, Seo Young Song, Zhi Hong Yang, Jae Eul Choi, Yoo Sun Noh, Suhyoung Park, Woo Jin Lim, Kye Man Cho, Han Dae Yun, Yong Pyo Lim
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  ABSTRACT: We developed a transgenic Chinese cabbage (Brassica rapa L. ssp. pekinensis) inbred line, Kenshin, with high tolerance to soft rot disease. Tolerance was conferred by expression of N-acyl-homoserine lactonase (AHL-lactonase) in Chinese cabbage through an efficient Agrobacterium-mediated transformation method. To synthesize and express the AHL-lactonase in Chinese cabbage, the plant was transformed with the aii gene (AHL-lactonase gene from Bacillus sp. GH02) fused to the PinII signal peptide (protease inhibitor II from potato). Five transgenic lines were selected by growth on hygromycin-containing medium (3.7% transformation efficiency). Southern blot analysis showed that the transgene was stably integrated into the genome. Among these five transgenic lines, single copy number integrations were observed in four lines and a double copy number integration was observed in one transgenic line. Northern blot analysis confirmed that pinIISP-aii fusion gene was expressed in all the transgenic lines. Soft rot disease tolerance was evaluated at tissue and seedling stage. Transgenic plants showed a significantly enhanced tolerance (2–3-fold) to soft rot disease compared to wild-type plants. Thus, expression of the fusion gene pinIISP-aii reduces susceptibility to soft rot disease in Chinese cabbage. We conclude that the recombinant AHL-lactonase, encoded by aii, can effectively quench bacterial quorum-sensing and prevent bacterial population density-dependent infections. To the best of our knowledge, the present study is the first to demonstrate the transformation of Chinese cabbage inbred line Kenshin, and the first to describe the effect of the fusion gene pinIISP-aii on enhancement of soft rot disease tolerance.
  Plant Cell Reports 04/2012; 28(10):1581-1591.
• Article: Field performance evaluation and genetic integrity assessment of cryopreserved papaya clones

  Adam Kaity, S. E. Ashmore, R. A. Drew
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  ABSTRACT: This paper is the first report of field performance and evaluation of morphological traits following cryopreservation in four genotypes of Carica papaya (Z6, 97, TS2 and 35). It also describes the successful establishment of in vitro plantlets following vitrification-based cryopreservation of shoot tips and their acclimatisation through to field establishment. Cloned plants resulting from untreated controls, as well as controls taken at three other stages of the cryopreservation process (dissection, pre-treatment, plant vitrification solution 2 (PVS2) treatment) and cryopreserved plants were established to ensure a rigorous appraisal of any variation. Results indicate no differences between any of the control plants or cryopreserved plants for either growth performance or morphology. In addition, both randomly amplified DNA fingerprinting and amplified DNA methylation polymorphism markers were used to assess any genomic or methylation changes in genotype 97 at four different developmental stages post cryopreservation (in vitro, acclimatisation and field). Only small genomic DNA modifications (0–8.3%) were detected in field stage plants and methylation modifications (0–4.3%) were detected at both the in vitro and field stages for samples treated with PVS2 or cryopreservation.
  Plant Cell Reports 04/2012; 28(9):1421-1430.
• Source

  Available from: PubMed Central

  Article: Regulation of seed germination and seedling growth by an Arabidopsis phytocystatin isoform, AtCYS6

  Jung Eun Hwang, Joon Ki Hong, Ji Hyun Je, Kyun Oh Lee, Dool Yi Kim, Sang Yeol Lee, Chae Oh Lim
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  ABSTRACT: Phytocystatins are cysteine proteinase inhibitors in plants that are implicated in the endogenous regulation of protein turnover and defense mechanisms against insects and pathogens. A cDNA encoding a phytocystatin called AtCYS6 (Arabidopsis thaliana phytocystatin6) has been isolated. We show that AtCYS6 is highly expressed in dry seeds and seedlings and that it also accumulates in flowers. The persistence of AtCYS6 protein expression in seedlings was promoted by abscisic acid (ABA), a seed germination and post-germination inhibitory phytohormone. This finding was made in transgenic plants bearing an AtCYS6 promoter–β-glucuronidase (GUS) reporter construct, where we found that expression from the AtCYS6 promoter persisted after ABA treatment but was reduced under control conditions and by gibberellin4+7 (GA4+7) treatment during the germination and post-germinative periods. In addition, constitutive over-expression of AtCYS6 retarded germination and seedling growth, whereas these were enhanced in an AtCYS6 knock-out mutant (cys6-2). Additionally, cysteine proteinase activities stored in seeds were inhibited by AtCYS6 in transgenic Arabidopsis. From these data, we propose that AtCYS6 expression is enhanced by the germination inhibitory phytohormone ABA and that it participates in the control of germination rate and seedling growth by inhibiting the activity of stored cysteine proteinases.
  Plant Cell Reports 04/2012; 28(11):1623-1632.
• Article: Characterization of an anther- and tapetum-specific gene and its highly specific promoter isolated from tomato

  S. X. Xu, G. S. Liu, R. D. Chen
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  ABSTRACT: A full-length genomic clone of 2,233bp long containing an anther- and tapetum-specific gene TomA108 was isolated and characterized from tomato. The gene was present in one copy per haploid genome. The isolated clone contained 5′ and 3′ untranslated regions of 810 and 170 nucleotides, respectively and a single intron with highly repetitive sequences. The cDNA encoded the protein with an apparent mass of 10.6kDa and a pI (isoelectric point) of 5.3. It was cysteine-rich and had an N-terminal hydrophobic domain with characteristics of a secretory signal. Amino acid sequence comparisons demonstrated that the protein was closely related to a family of cereal seed storage proteins and protease inhibitors. The fusion of β-glucuronidase to the TomA108 promoter demonstrated that the promoter was highly active from early-meiosis to free microspores production in tapetum of tobacco. This strong and highly specific promoter can be potentially used to generate male sterility for efficient production of plant hybrids.
  Plant Cell Reports 04/2012; 25(3):231-240.
• Article: Genetic and biochemical analysis of Hypericum perforatum L. plants regenerated after cryopreservation

  Martina Urbanová, Ján Košuth, Eva Čellárová
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  ABSTRACT: Shoot-tips from in vitro cultured Hypericum perforatum L. genotypes were subjected to assessments of developmental competence, genetic stability, and biosynthetic ability to identify critical points during cryopreservation. Survival rate, chromosome number stability, alteration in VNTR sequences and hypericin content were evaluated, in plants after pre-culture, and two subsequent cryogenic steps (cryoprotection and cooling) and those recovered from cryopreserved meristems. Pre-culture and cryoprotection treatments, did not reveal any significant differences, in these studied characteristics. Genetic stability was assessed by chromosome counts and analysis of variability in the VNTR sequences. No changes in chromosome number were detected in comparison with the untreated control but minor alterations were revealed in non-coding sequences. The content of hypericin after the recovery of cryopreserved meristems remained comparable with the unfrozen control. The controlled rate freezing technique used for cryopreservation was relevant for restoration of genetic and biochemical stability in Hypericum perforatum L. shoot-tips.
  Plant Cell Reports 04/2012; 25(2):140-147.
• Article: Stress-related variation in antioxidative enzymes activity and cell metabolism efficiency associated with embryogenesis induction in isolated microspore culture of triticale (x Triticosecale Wittm.)

  Iwona Żur, Ewa Dubas, Elżbieta Golemiec, Magdalena Szechyńska-Hebda, Gabriela Gołębiowska, Maria Wędzony
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  ABSTRACT: Isolated microspore cultures of two spring triticale (x Triticosecale Wittm.) cultivars were used to examine the effect of various stress treatments (either high—32°C or low—5°C temperature with or without nitrogen/carbohydrate starvation) applied to excised anthers on the effectiveness of microspore embryogenesis induction. To quantify the effects of pretreatment conditions, the activity of antioxidative enzymes (catalase, peroxidase and superoxide dismutase) together with respiration rate and heat emission were measured. It was observed that heat shock treatment applied as the only one stress factor increased the activity of antioxidative enzymes which suggests intensive generation of reactive oxygen species. Such pretreatment effectively triggered microspore reprogramming but drastically decreased microspore viability. After low temperature treatment, the activity of antioxidative enzymes was similar to the control subjected only with the stress originated from the transfer to in vitro culture conditions. This pretreatment decreased the number of microspores entering embryogenesis but sustained cell viability and this effect prevailed in the final estimation of microspore embryogenesis effectiveness. For both, low- and high-temperature treatments, interaction with starvation stress was beneficial increasing microspore viability (at 5°C) or efficiency of embryogenesis induction (at 32°C). The latter treatment significantly reduced cell metabolic activity. Physiological background of these effects seems to be different and some hypothetical explanations have been discussed. Received data indicate that in triticale, anther preculture conditions could generate oxidative stress and change the cell metabolic activity which could next be reflected in the cell viability and the efficiency of microspore embryogenesis.
  Plant Cell Reports 04/2012; 28(8):1279-1287.
• Article: Impact of two different types of heat stress on chloroplast movement and fluorescence signal of tobacco leaves

  Jiří Frolec, Jiří Řebíček, Dušan Lazár, Jan Nauš
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  ABSTRACT: Although the chloroplast movement can be strongly affected by ambient temperature, the information about chloroplast movement especially related to high temperatures is scarce. For detailed investigation of the effects of heat stress (HS) on tobacco leaves (Nicotiana tabacum L. cv. Samsun), we used two different HS treatments in dark with wide range of elevated temperatures (25–45°C). The leaf segments were either linearly heated in water bath at heating rate of 2°Cmin−1 from room temperature up to maximal temperature (T m) and then linearly cooled down to 25°C or incubated for 5min in water bath at the same T m followed by 5min incubation at 25°C (T-jump). The changes in light-induced chloroplast movement caused by the HS pretreatment were detected after the particular heating regime at 25°C using a method of time-dependent collimated transmittance (CT) and compared with the chlorophyll O–J–I–P fluorescence rise (FLR) measurements. The inhibition of chloroplast movement started at about 40°C while the fluorescence parameters responded generally at higher T m. This difference in sensitivity of CT and FLR was higher for the T-jump than for the linear HS indicating importance of applied heating regime. A possible influence of chloroplast movement on the FLR measurement and a physiological role of the HS-impaired chloroplast movement are discussed. KeywordsChlorophyll fluorescence induction curve-Chloroplast translocation-Cytoskeleton-High temperature-JIP test- Nicotiana tabacum
  Plant Cell Reports 04/2012; 29(7):705-714.