Urte Schlüter

• Heinrich Heine University Düsseldorf

Accurate assessment of leaf functional traits is crucial for a diverse range of applications from crop phenotyping to parameterizing global climate models. Leaf reflectance spectroscopy offers a promising avenue to advance ecological and agricultural research by complementing traditional, time-consuming gas exchange measurements. However, the devel...

C 4 photosynthesis has arisen from the ancestral C 3 state in over sixty lineages of angiosperms. It is widely accepted that an early step in C 4 evolution is associated with the appearance of so-called C 2 photosynthesis caused by loss of glycine decarboxylase activity from mesophyll cells followed by activation in the bundle sheath. Although chan...

Photosynthesis underpins life on Earth, serving as the primary energy source while regulating global carbon and water cycles, thereby shaping climate and vegetation. Advancing photosynthesis research is essential for improving crop productivity and refining photosynthesis models across scales, ultimately addressing critical global challenges such a...

C3 photosynthesis can be complemented with a C4 carbon concentrating mechanism (CCM) to minimize photorespiratory losses. C4 photosynthesis is often more efficient than C3 under steady‐state conditions. However, the C4 CCM depends on inter‐cellular metabolite concentration gradients, which must increase following increases in light intensity and co...

Motivation Identifying cis-regulatory elements (CREs) is crucial for analyzing gene regulatory networks. Next generation sequencing methods were developed to identify CREs but represent a considerable expenditure for targeted analysis of few genomic loci. Thus, predicting the outputs of these methods would significantly cut costs and time investmen...

C 3 ‐C 4 intermediate photosynthesis has evolved at least five times convergently in the Brassicaceae, despite this family lacking bona fide C 4 species. The establishment of this carbon concentrating mechanism is known to require a complex suite of ultrastructural modifications, as well as changes in spatial expression patterns, which are both tho...

Motivation: The identification of cis-regulatory elements (CREs) is crucial for the analysis of gene regulatory networks in plants. Several next generation sequencing (NGS)-based methods were developed to identify CREs. However, these methods can be time-consuming and costly. They also involve creating sequencing libraries for the entire genome. Si...

C 4 photosynthesis has arisen from the ancestral C 3 state in over sixty lineages of angio-sperms. It is widely accepted that an early step in C 4 evolution is restriction of glycine decarboxylase activity to bundle sheath cells to generate the so-called C 2 pathway. In C 2 Moricandia species, changes to the cis -regulatory region controlling expre...

Photosynthesis in both crops and natural vegetation allows light energy to be converted into chemical energy, and thus forms the foundation for almost all terrestrial trophic networks on Earth. The efficiency of photosynthetic energy conversion plays a crucial role in determining the portion of incident solar radiation that can be used to generate...

Research on C4 and C3‐C4 photosynthesis has attracted significant attention because the understanding of the genetic underpinnings of these traits will support the introduction of its characteristics into commercially relevant crop species. We used a panel of 19 taxa of 18 Brassiceae species with different photosynthesis characteristics (C3 and C3‐...

Carbon concentrating mechanisms enhance the carboxylase efficiency of the central photosynthetic enzyme rubisco by providing supra-atmospheric concentrations of CO2 in its surrounding. In the C4 photosynthesis pathway, this feat is realised by combinatory changes to leaf biochemistry and anatomy. In contrast to the C4 pathway, carbon concentration...

The entry of carbon dioxide from the atmosphere into the biosphere is mediated by the enzyme Rubisco, which catalyzes the carboxylation of ribulose 1,5-bisphosphate (RuBP) as the entry reaction of the Calvin Benson Bassham cycle (CBBC), leading to the formation of 2 molecules of 3-phosphoglyceric acid (3PGA) per CO2 fixed. 3PGA is reduced to triose...

C3 -C4 intermediate photosynthesis has evolved multiple times convergently and independently in the Brassicaceae, although the family lacks bona fide C4 species. Evolution of C3 -C4 intermediate photosynthesis requires a reconfiguration of gene-regulatory networks, modified spatial expression patterns of multiple genes and ultrastructural adjustmen...

Cleomaceae is closely related to Brassicaceae and includes C3, C3–C4, and C4 species. Thus, this family represents an interesting system for studying the evolution of the carbon concentrating mechanism. However, inadequate genetic information on Cleomaceae limits their research applications. Here, we characterized 22 Cleomaceae accessions [3 genera...

Altered transcript abundances and cell specific gene expression patterns that are caused by regulatory divergence play an important role in the evolution of C4 photosynthesis. How these altered gene expression patterns are achieved and whether they are driven by cis- or trans-regulatory changes is mostly unknown. To address this question, we invest...

Moricandia is a genus belonging to the family Brassicaceae. C3 and C3C4 photosynthesis Moricandia species exist in a close phylogenetic proximity, as well as to Brassica crops. Here, we performed PacBio genome sequencing on M. moricandioides and M. arvensis. The genomes were assembled using Flye assembler, then polished with Illumina reads and redu...

Alanine and aspartate are essential transfer metabolites for C4 species of the NAD‐malic enzyme and the phosphoenolpyruvate carboxykinase subtype. To some degree both amino acids are also part of the metabolite shuttle in NADP‐malic enzyme plants. In comparison with C3 species, the majority of C4 species are therefore characterised by enhanced expr...

Harnessing natural variation in photosynthetic capacity is a promising route towards yield increases, but physiological phenotyping is still too laborious for large scale genetic screens. Here, we evaluate the potential of leaf reflectance spectroscopy to predict parameters of photosynthetic capacity in Brassica oleracea and Zea mays, a C3 and a C4...

Sustainable agriculture demands reduced input of man-made nitrogen (N) fertilizer, yet N2 fixation limits the productivity of crops with heterotrophic diazotrophic bacterial symbionts. We investigated floating ferns from the genus Azolla that host phototrophic diazotrophic Nostoc azollae in leaf pockets and belong to the fastest growing plants. Exp...

Flowering time control (FTi) is well examined in the long day plant Arabidopsis and increasing knowledge is available for the short day plant rice. In contrast little is known in the day-neutral and agronomically important crop plant maize. To learn more about FTi and to identify novel regulators in this species we first compared the time points of...

RNA-seq, the measurement of steady-state RNA levels by next generation sequencing, has enabled quantitative transcriptome analyses of complex traits in many species without requiring the parallel sequencing of their genomes. The complex trait of C4 photosynthesis, which increases photosynthetic efficiency via a biochemical pump that concentrates CO...

C4 photosynthesis enables high photosynthetic energy conversion efficiency as well as high nitrogen and water use efficiencies. Given the multitude of biochemical, structural and molecular changes in comparison with C3 photosynthesis, it appears unlikely that such a complex trait would evolve in a single step. C4 photosynthesis is therefore believe...

Most terrestrial plants benefit from the symbiosis with arbuscular mycorrhizal fungi (AMF) mainly under nutrient-limited conditions. Here the crop plant Zea mays was grown with and without AMF in a bi-compartmented system separating plant and phosphate (Pi)-source by a hyphae-permeable membrane. Thus Pi was preferentially taken up via the mycorrhiz...

Eragrostis tef (Zucc.) Trotter, a tetraploid cereal of Ethiopia, has a tall and slender stem that is susceptible to lodging, causing yield loss of ˜15%–45% each year. Genes conferring lodging resistance through the control of plant height involves gibberellins (GA) metabolism genes that have not been identified and characterized in E. tef. The aim...

Almost all protease families have been associated with plant development, particularly senescence, which is the final developmental stage of every organ before cell death. Proteolysis remobilizes and recycles nitrogen from senescent organs that is required, for example, seed development. Senescence-associated expression of proteases has recently be...

Abiotic stress causes disturbances in the cellular homeostasis. Re-adjustment of balance in carbon, nitrogen and phosphorus metabolism therefore plays a central role in stress adaptation. However, it is currently unknown which parts of the primary cell metabolism follow common patterns under different stress conditions and which represent specific...

Successful application of genetic transformation for integration of a transgene is much dependent upon availability of an efficient in vitro plant regeneration procedure and detection of transgene insertion and expression. Isolated immature embryos (IEs) of Eragrostis tef cultivar DZ-01-196 were used for embryogenic callus formation and the callus...

Plants are increasingly used as alternative expression hosts for the production of recombinant proteins offering many advantages including higher biomass and the ability to perform post-translational modifications on complex proteins. Key challenges for optimized accumulation of recombinant proteins in a plant system still remain, including endogen...

Background: Maize is a major crop plant, grown for human and animal nutrition, as well as a renewable resource for bioenergy. When looking at the problems of limited fossil fuels, the growth of the world's population or the world's climate change, it is important to find ways to increase the yield and biomass of maize and to study how it reacts to...

OPTIMAS Database Schema. The OPTIMAS Database Schema can be divided into two main parts, the metadata on the one side and the data domain schemas on the other side. The metadata and each data domain schema are linked through table optimas.t103_measurement_ value. The primary key of the data domain entry is stored in t103_ measurement_value_id while...

Crop plant development is strongly dependent on the availability of nitrogen in the soil and the efficiency of nitrogen utilization for biomass production and yield. However, knowledge about molecular responses to nitrogen deprivation derives mainly from the study of model species. In this paper, the metabolic adaptation of source leaves to low N w...

Plants are an effective and inexpensive host for the production of commercially interesting heterologous recombinant proteins. The Escherichia coli-derived glutathione reductase was transiently expressed as a recombinant model protein in the cytosol of tobacco plants using the technique of leaf agro-infiltration. Proteolytic cysteine protease activ...

Eragrostis tef, a tall stature and highly nutritious cereal grown in East Africa, has a serious lodging problem that reduces its productivity considerably. Certain plant-growth regulators are known to restrict growth and consequently improve lodging resistance in cereals by affecting gibberellin biosynthesis. The effect on height of growth regulato...

Crop plant development is strongly dependent on the availability of nitrogen (N) in the soil and the efficiency of N utilization for biomass production and yield. However, knowledge about molecular responses to N deprivation derives mainly from the study of model species. In this article, the metabolic adaptation of source leaves to low N was analy...

We systematically analyzed a developmental gradient of the third maize (Zea mays) leaf from the point of emergence into the light to the tip in 10 continuous leaf slices to study organ development and physiological and biochemical functions. Transcriptome analysis, oxygen sensitivity of photosynthesis, and photosynthetic rate measurements showed th...

Plant cystatins have been the object of intense research since the publication of a first paper reporting their existence more than 20 years ago. These ubiquitous inhibitors of Cys proteases play several important roles in plants, from the control of various physiological and cellular processes in planta to the inhibition of exogenous Cys proteases...

Protease inhibitors are a promising complement to Bt toxins for the development of insect-resistant transgenic crops, but their limited specificity against proteolytic enzymes and the ubiquity of protease-dependent processes in living organisms raise questions about their eventual non-target effects in agroecosystems. After a brief overview of the...

The general potential of plant cystatins for the development of insect-resistant transgenic plants still remains to be established given the natural ability of several insects to compensate for the loss of digestive cysteine protease activities. Here we assessed the potential of cystatins for the development of banana lines resistant to the banana...

The non-expressor of pathogenesis-related genes 1 (NPR1) is an essential positive regulator of salicylic acid (SA)-induced pathogenesis-related (PR) gene expression and systemic acquired resistance (SAR). Two novel full length NPR1-like genes; MNPR1A and MNPR1B, were isolated from banana by application of the PCR and rapid amplification of cDNA end...

Symbiotic nitrogen fixation is sensitive to dark chilling (7 degrees C-15 degrees C)-induced inhibition in soybean (Glycine max). To characterize the mechanisms that cause the stress-induced loss of nodule function, we examined nodule structure, carbon-nitrogen interactions, and respiration in two soybean genotypes that differ in chilling sensitivi...

Bacillus thuringiensis (Bt) crops require a high dosage of Bt toxin to delay development of insect resistance, in particular, when the refuge strategy is applied. This strategy is threatened by plant developmental and environmental factors that might reduce Bt toxin concentration and Bt efficacy in Bt crops. Growth of Bt (Cry1Ac) cotton under prolo...

Legume crops are an important source of protein, oil and secondary metabolites and they are also used as a natural nitrogen source in agriculture, particularly in Africa, because of presence of nitrogen-fixing bacteria in specialized organs called “nodules”. The symbiotic association between the plant and nitrogen-fixing bacteria in nodule formati...

Plants are exposed to a range of environmental stresses and have to adapt physiologically to these as the local environment changes. The recognition and signalling pathways regulating the responses to abiotic stresses are similar to those used for responding to biotic stresses. The adaptation to one stress condition can therefore affect tolerance t...

One of the major sugars present in the plant cell wall is d-galacturonate, the dominant monosaccharide in pectic polysaccharides. Previous work indicated that one of the activated precursors necessary for the synthesis of pectins is UDP-d-galacturonate, which is synthesized from UDP-d-glucuronate by a UDP-d-glucuronate 4-epimerase (GAE). Here, we r...

The indigenous North American Cranberry (Vaccinium macrocarpon), when cultivated in specially constructed cranberry bogs, is normally flooded in winter to prevent frost injury. This protection under ice can give rise to prolonged periods of anoxia, which depending on the state of the vines and environmental conditions, can cause severe oxygen-depri...

In the Arabidopsis mutant sdd1‐1, a point mutation in a single gene (SDD1) causes specific alterations in stomatal density and distribution. In comparison to the wild type (C24), abaxial surfaces of sdd1‐1 rosette leaves have about 2.5‐fold higher stomatal densities. This mutant was used to study the consequence of stomatal density on photosynthesi...

Brassinosteroids (BRs) are essential regulators of growth and development. BR-deficient mutants such as cpd/cbb3 and dwf4 display extreme dwarfism due to a failure in cell elongation. To avoid the severe pleiotropic effects caused by the extreme growth defect, transgenic Arabidopsis lines carrying a construct for antisense inhibition of CPD gene ex...

Mature green leaves of Acorus calamus and Iris pseudacorus have been shown to survive at least 28 d of total anoxia in the dark during the growing season, increasing up to 75 d and 60 d in overwintering leaves in A. calamus and I. pseudacorus, respectively. During the period of anaerobic incubation the glycolytic rate is reduced, carbohydrate reser...

We investigated the carbohydrate concentration of plant species naturally growing in habitats with a high risk of oxygen shortage (Senecio aquaticus Hill,Myosotis palustris (L.) L. em.Rchb) and congeneric species from drier sites (Senecio jacobaea L.,Myosotis arvensis (L.)Hill) Plants from the four species were cultivated in either nitrogen-flushed...