My main research projects centred around receptor biology and the downstream substrates of these receptors. I characterised receptor interactions and phosphorylation events controlling lateral root development in Arabidopsis thaliana.

Leucine Rich Repeat-Receptor Like Kinases (LRR-RLKs) are central for cellular signalling pathways in plants to control processes including growth and development, innate immunity and somatic embryogenesis. In Arabidopsis thaliana the RLK BRI1 Associated Kinase 1 (BAK1) has been implicated in several different pathways including brassinosteroid signalling and defence responses by interaction with Brassionosteroid Insensitive 1 (BRI1) and Flagallin Sensing 2 (FLS2) respectively. The aims of this project were to translate knowledge already known from Arabidopsis thaliana and characterise any similarities or difference that may be present in tomato, as a valuable crop species. BAK1 was chosen as the central aspect of the research as it had been implicated in both defence and growth regulated pathways. Functional identification of BAK1 from Solanum lycopersicum was performed. Confocal microscopy of SlBAK1 and its partner receptor SlBRI1 exhibited plasma membrane localisation. Kinase assays have shown SlBAK1, SlBRI1 and SlFLS2 all encode for active kinase domains and exhibit autophosphorylation activity. Transphosphorylation was also observed between SlBAK1 and SlBRI1, but not between SlBAK1 and SlFLS2. A TILLING screen of SlBAK1 recovered two missense mutations (bak1-1 and bak1-3) both in the kinase domain. Kinase activity analysis of both point mutations revealed that neither autophosphorylation nor transphosphorylation was affected. Analysis of the mutations after treatment with BL and flg22 show that both mutants respond in a very similar manner to wild type plants. Bacterial infection of SlBAK1 mutant lines demonstrated increased resistance from bak1-1 but not bak1-3. The project identified several similarities and differences between Arabidopsis and tomato signalling pathways highlighting the need to translate the knowledge gained in model species to crops. Further sevelopments could provide information for future improvement of economically important crops species.