Untersuchungen zum Einfluss von reguliertem Vesikeltransport auf die Signaltransduktion in Pflanzenzellen am Beispiel des Brassinosteroidrezeptors, BRI1

• Applicant: Professor Dr. Niko Geldner
• Subject Area: Plant Cell and Developmental Biology
• Term: Funded in 2003
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5415704

Regulated vesicle trafficking of receptors has been recognised as an integral part of signalling pathways in animals. In plants, molecular and genetic approaches in Arabidopsis identified important signalling pathways, including a unique steroid signalling pathway, involving a plasma-membrane localised receptor-kinase, BRI1. BRI1-receptor mediated brassinosteroid perception is one of the best understood to date. However, nothing is known in plants about receptor trafficking and its importance for signal transduction. I propose to use BRI1 as a model and to investigate BRI1 trafficking and its importance for brassinosteroid signalling dynamics. BRI1-GFP is detected in root epidermal cells, a well-suited system for cell biological manipulations. BRI1-ligand and inhibitors can be applied exogenously and a large inventory of non-lethal brassinosteroid mutants is available. Facile Arabidopsis transformation protocols will not only allow me to investigate trafficking of engineered BRI1 variants, but also to screen for PCR-mutagenised BRI1 trafficking mutants in defined genetic backgrounds. This will be done in a in-planta cell system, with proteins that are stably expressed to endogenous levels. The ability to combine genetic, molecular biological and cell biological tools will not only lead to new insights into brassinosteroid signalling but has the protential to make Arabidopsis an attractive general model for investigation of receptor cell biology.

• DFG Programme: Emmy Noether International Fellowships
• Participating Person: Professorin Dr. Joanne Chory