Integrierte omics Analysen und funktionelle Untersuchungen zum Faltungsmechanismus von Zellwänden bei austrocknungstoleranten Wiederauferstehungspflanzen
Zusammenfassung der Projektergebnisse
Crateostigma plantagineum is a well-studied representative of the desiccation tolerant vascular resurrection plants. Upon dehydration the cell volume shrinks and the leaves fold up to avoid photooxidative damage through light. These processes are reversed during rehydration and require a flexible cell wall. To understand how C. plantagineum achieves the reversible shrinkage and folding cell wall changes were examined on the microscopic, biochemical and molecular level. A focus was on pectin composition and cell wall protein complexes formed by the glycine rich protein CpGRP1 and CpWAK. Additionally the polygalacturonase inhibiting protein CpPGIP was characterized as a possible enzyme inhibiting polygalacturonase. The pectin composition was analysed in different cell wall fractions with monoclonal antibodies against homogalacturonan, rhamnogalacturonan-I, rhamnogalacturonan –II and hemicelluloses epitopes. The data demonstrate changes in pectin composition. It is hypothesized that these changes support the flexibility of the cell wall during dehydration / rehydration. The glycine rich protein CpGRP1 seems to have a central role in cellular adaption to dehydration. It interacts with pectin and demethylesterified pectin from dehydrated leaves presents more binding sites for the interaction than pectin from hydrated leaves. CpGRP1 is also able to selectively bind to the lipid compounds phosphatidic acid and cardiolipin. CpGRP1 interacts with a cell wall associated kinase CpWAK1 and it is proposed that changes in pectin composition are sensed by the CpGRP1-CpWAK1 complex leading to the activation of dehydration responses and leaf folding.
Projektbezogene Publikationen (Auswahl)
- Craterostigma plantagineum cell wall composition is remodelled during desiccation and the glycine-rich protein CpGRP1 interacts with pectins through clustered arginines The Plant Journal (2019) 100,661-676
Jung N., Giarola V., Chen P., Knox P., Bartels D.
(Siehe online unter https://doi.org/10.1111/tpj.14479) - “Analysis of two selected cell wall proteins and one lncRNA involved in desiccation tolerance of the resurrection plant “Craterostigma plantagineum” (University of Bonn 2019)
Chen, Peilei
- The dynamic responses of cell walls in resurrection plants during dehydration and rehydration Front. Plant Sci.( 2020)
Chen P., Jung N., Giarola V., Bartels D.
(Siehe online unter https://doi.org/10.3389/fpls.2019.01698) - „Molecular and biochemical studies of the Craterostigma plantagineum” cell wall during dehydration and rehydration“ (University of Bonn, February 2020)
Jung, Niklas