CLE/RLK regulated vascular signalling pathways in plants
Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
Entire postembryonic production of plant tissues are maintained by meristems. These specialized structures provide a pool of undifferentiated stem cells and a limited population of proliferating cells which are destined for differentiation in order to generate a variety of tissues in the plant body. For the forest trees, a large part of the biomass is produced by a secondary meristem called vascular cambium. Vascular cambium forms a continuous cylinder of meristematic cells in the stem, producing both secondary phloem and secondary xylem or wood. Maintenance and differentiation of meristems are much conserved and strictly regulated for the production of correct tissues and organs. Receptor-like kinases (RLKs) are characterized by the presence of a signal sequence, a putative amino-terminal extracellular domain connected to a carboxyl-terminal intracellular kinase domain with a trans-membrane domain. They control a wide-range of physiological processes, including development, disease resistance, hormone perception, and self-incompatibility. Leucine-rich repeat receptor-like kinases (LRR-RLKs) represent the largest group of RLKs in the Arabidopsis thaliana genome, with more than 200 members.Several LRR-RLKs and their putative ligands CLAVATA3 (CLV3)/ Endosperm Surrounding Region (ESR)-related (CLE) peptides have been found to be involved in the regulation of vascular development. In the current study, the main aim was to study the tissue-specific expression patterns of LRR-RLK genes in A. thaliana by generating promoter::GUS transcriptional fusions. The results confirmed that these genes are expressed in the vasculature of the plants. Moreover, Populus orthologs of the CLE genes were detected by bioinformatic tools as putative ligands of LRR-RLKs and an extensive quantitative Real-Time Reverse Transcriptase PCR (qRT-PCR) analysis was performed to test for significant changes in transcript levels across different tissue types. As a result, a collection of potential candidate genes for vascular development were identified.
Place, publisher, year, edition, pages
2009. , 46 p.
IdentifiersURN: urn:nbn:se:umu:diva-26276OAI: oai:DiVA.org:umu-26276DiVA: diva2:241380
KBF30, UPSC, Umeå universitet, Umeå (English)
Zheng, Bo, Forskare
Hurry, Vaughan, Prof