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Zuther, E.

Publications and source records attributed to Zuther, E..

5 recordsLinked to original sources

Regulation of plant metabolism under elevated CO2

Plant responses to changing environments afford complex regulation at transcriptome and proteome level to maintain metabolic homeostasis. Homeostasis itself constitutes a complex and dynamic equilibrium of metabolic reactions and transport processes among cellular compartments. In the present study, we aimed at the highest possible resolution of this network by combining analysis of transcriptome, proteome and subcellular resolved metabolome of plants exposed to rising carbon dioxide concentrations over a time course of one week. To prove suitability of our approach, we included mutants affected in photorespiratory metabolism and, thus, should deviate from the wildtype in their response to elevated CO2. Our multi-omics analysis revealed that the hpr1-1 mutant, defective in peroxisomal hydroxypyruvate reduction, is also affected in cytosolic pyruvate metabolism, reaching out to cysteine synthesis, while the hexokinase mutant hxk1 displays a disturbed redox balance upon changing CO2 levels. For the third mutant, defective in the mitochondrial protein BOU, we found compelling evidence that the function of this transporter is related to lipoic acid metabolism, thus challenging current interpretations. This demonstrates that the combined omics approach introduced here opens new insights into complex metabolic interaction of pathways shared among different cellular compartments.

plant biology↗

Unveiling the potato cultivars with microbiome interactive traits for sustainable agricultural production

Root traits significantly shape rhizosphere microbiomes, yet their interaction with microbes is often overlooked in plant breeding programs. Here, we propose that selecting modern cultivars based on microbiome interactive traits (MITs), such as root biomass, exudate patterns and the rhizosphere microbiome, can enhance agricultural sustainability by interacting effectively with soil microbiomes, which in turn, promotes plant growth and resistance to stress, thereby reducing reliance on synthetic crop protectants. Through a stepwise selection process (in silico and in vitro) that started with approximately 1000 potato genotypes, we chose 51 potato cultivars based on known phenotypical properties and distinct root exudate patterns. We conducted a greenhouse experiment to evaluate their capacity to interact with the soil microbiome and to assess their MITs. Our findings revealed that cultivars significantly influence plant growth, metabolite profiles, and rhizosphere fungal community composition. Moreover, we observed a positive correlation between microbial community diversity and root biomass. Additionally, leaf metabolites were correlated with rhizosphere bacterial composition, supporting the plant holobiont framework. Utilising z-scores, we aggregated all data related to plant growth, metabolomes, and microbiomes, creating a classification of 51 cultivars based on a gradient of MITs. By examining the distribution of low, medium, and high MITs, we identified a group of 11 potato cultivars suitable for further studies to assess their resilience and productivity under low-input production systems. This study provides an in-depth correlation between microbiome and several plant traits across 51 cultivars, offering tools to facilitate and expedite the incorporation of microbiome traits into breeding goals to support sustainable agriculture.

microbiology↗

CWLP and PRP940 form plasma-membrane nanodomain complexes with aquaporins, interact with PP2A and contribute to dehydration tolerance

The C-type hybrid-proline-rich protein (HyPRP) AtCWLP and its homolog AtPRP940 are referred as cell wall (CW)-plasma-membrane (PM) linker proteins, but little is known about their functions. Here we show that N-terminal proline-rich domains of CWLP and PRP940, containing glycosylated hydroxyproline residues, contact the CW, while their C-terminal 8CM domains function as PM-scaffolds. Both proteins are detected in PM nanodomains (PM-ND) and show co-localization and co-immunoprecipitation with aquaporins PIP2;1 and PIP2;7. Inhibition of actin polymerization by latrunculin B promotes CWLP-endosome appearance, while blocking the actomyosin-based transport by a truncated form of myosin XI-K relaxes lateral boundaries of CWLP-PIP2;1 PD-NDs. Mass spectrometry data indicate that CWLP co-purifies with dynamins implicated in fission of endocytic PD-ND invaginations. Lack of co-localization and co-immunoprecipitation with aquaporin-binding flotillin (FLOT2) indicates that CWLP and PRP940 mark a new distinct type of PM-ND. Yeast two-hybrid and co-immunoprecipitation assays demonstrate that CWLP and PRP940 interact with multiple aquaporins and several protein phosphatase PP2A-B regulatory subunits. By preventing irreversible separation of CW and PM, and likely assisting PP2A-mediated dephosphorylation of aquaporins and closure of their water channels, overexpression of CWLP confers tolerance to plasmolysis, dehydration and freezing in Arabidopsis and to water shortage in potato plants. Summary StatementArabidopsis Hybrid-Proline-Rich Proteins CWLP and PRP940 occur in association with dynamins, recruit PP2A protein phosphatases to aquaporin water channels in plasma-membrane (PM) nanodomains and elevate tolerance to cellular dehydration.

plant biology↗

Characterisation of the ERF102 to ERF105 genes of Arabidopsis thaliana and their role in the response to cold stress

The ETHYLENE RESPONSE FACTOR (ERF) genes of Arabidopsis thaliana form a large family encoding plant-specific transcription factors. Here, we characterise the four phylogenetically closely related ERF102/ERF5, ERF103/ERF6, ERF104 and ERF105 genes. Expression analyses revealed that these four genes are similarly regulated by different hormones and abiotic stresses. Analyses of tissue-specific expression using promoter:GUS reporter lines revealed their predominant expression in root tissues including the root meristem (ERF103), the quiescent center (ERF104) and the root vasculature (all). All GFP-ERF fusion proteins were nuclear-localised. The analysis of insertional mutants, amiRNA lines and 35S:ERF overexpressing transgenic lines indicated that ERF102 to ERF105 have only a limited impact on regulating shoot and root growth. Previous work had shown a role for ERF105 in the cold stress response. Here, measurement of electrolyte leakage to determine leaf freezing tolerance and expression analyses of cold-responsive genes revealed that the combined activity of ERF102 and ERF103 is also required for a full cold acclimation response likely involving the CBF regulon. Together, these results suggest a common function of these ERF genes in regulating root architecture and the response to cold stress.

plant biology↗

Transcriptional and post-transcriptional regulation and transcriptional memory of chromatin regulators in response to low temperature

Chromatin regulation ensures stable repression of stress-inducible genes under non-stress conditions and transcriptional activation and memory of such an activation of those genes when plants are exposed to stress. However, there is only limited knowledge on how chromatin genes are regulated at the transcriptional and post-transcriptional level upon stress exposure and relief from stress. We have therefore set-up a RT-qPCR-based platform for high-throughput transcriptional profiling of a large set of chromatin genes. We find that the expression of a large fraction of these genes is regulated by cold. In addition, we reveal an induction of several DNA and histone demethylase genes and certain histone variants after plants have been shifted back to ambient temperature (deacclimation), suggesting a role in the memory of cold acclimation. We also re-analyse large scale transcriptomic datasets for transcriptional regulation and alternative splicing (AS) of chromatin genes, uncovering an unexpected level of regulation of these genes, particularly at the splicing level. This includes several vernalization regulating genes whose AS results in cold-regulated protein diversity. Overall, we provide a profiling platform for the analysis of chromatin regulatory genes and integrative analyses of their regulation, suggesting a dynamic regulation of key chromatin genes in response to low temperature stress.

plant biology↗