Dokument: Identification of genes involved in suppression of growth- and stress- related defects associated with wall hypoacetylation
| Titel: | Identification of genes involved in suppression of growth- and stress- related defects associated with wall hypoacetylation | |||||||
| URL für Lesezeichen: | https://docserv.uni-duesseldorf.de/servlets/DocumentServlet?id=69082 | |||||||
| URN (NBN): | urn:nbn:de:hbz:061-20250324-110623-7 | |||||||
| Kollektion: | Dissertationen | |||||||
| Sprache: | Deutsch | |||||||
| Dokumententyp: | Wissenschaftliche Abschlussarbeiten » Dissertation | |||||||
| Medientyp: | Text | |||||||
| Autor: | Natarajan, Rajesh Kumar [Autor] | |||||||
| Dateien: |
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| Beitragende: | Pauly, Markus [Gutachter] Prof. Dr. Usadel, Björn [Gutachter] | |||||||
| Dewey Dezimal-Klassifikation: | 500 Naturwissenschaften und Mathematik » 570 Biowissenschaften; Biologie | |||||||
| Beschreibung: | Plant cell walls are composed of intricately structured polymers, including polysaccharides that are often modified with O-linked acetate groups. These modifications are crucial for plant
growth, development, and stress responses. However, understanding the biological significance of cell wall acetylation has been challenging due to the pleiotropic phenotypes exhibited by mutants with altered acetylation levels. A key focus of this study is the ALTERED XYLOGLUCAN9 (AXY9) gene, which plays a significant role in the O-acetylation of multiple wall polysaccharides. The loss of function of AXY9 results in severe developmental defects, including extreme dwarfism and male sterility. To overcome the technical challenges associated with studying this mutant, a conditionally complemented axy9 line (pAXY) was developed. Through a forward genetic screen on pAXY mutants, novel genes involved in the suppression of the phenotype associated with hypoacetylation were identified. These findings reveal that the recovery of growth in these suppressor mutants is not directly linked to the hypoacetylation. Instead, the study uncovers alternative compensatory pathways that contribute to growth recovery, such as the involvement of brassinosteroid (BR) signaling. Specifically, the suppression of a WD40 and PHOX3 genes appears to enhance BR signaling, promoting growth despite reduced wall acetylation. The interaction between cell wall integrity and hormone signaling pathways highlights a complex regulatory network that compensates for defects in wall structure. In addition to these genetic insights, this thesis also utilizes synthetic biology approach to reconstruct the xyloglucan (XyG) backbone O-acetylation pathway in Yarrowia lipolytica, a non-conventional yeast species. While significant strides have been made in identifying the molecular components involved in plant cell wall polymer synthesis, how these components interact to control the length and decoration patterns of polysaccharides remains largely unknown. By co-expressing the CSLC4, XXT2, and XyBAT1 genes, an O-acetylated β-1,4-glucan backbone was produced, providing valuable insights into the biosynthesis of plant cell wall polysaccharides. This approach not only advances our understanding of the mechanisms of O-acetylation but also demonstrates the potential of Y. lipolytica as a versatile platform for synthetic biology and metabolic engineering. Overall, this research sheds light on the genetic and molecular mechanisms that regulate cell wall O-acetylation in plants. | |||||||
| Lizenz: |  Dieses Werk ist lizenziert unter einer Creative Commons Namensnennung 4.0 International Lizenz | |||||||
| Fachbereich / Einrichtung: | Mathematisch- Naturwissenschaftliche Fakultät | |||||||
| Dokument erstellt am: | 24.03.2025 | |||||||
| Dateien geändert am: | 24.03.2025 | |||||||
| Promotionsantrag am: | 11.09.2024 | |||||||
| Datum der Promotion: | 24.02.2025 |
