SEARCH FOR FUNCTIONS OF RECEPTOR-LIKE KINASES

The model organism Arabidopsis thaliana is closely related to the Brassica genus; therefore, the obtained information can be used more directly in Bressica species. Plantsare sessile organisms and are exposed to numerous, variable, conditions such as light, biotic and abiotic stresses. They must adjust their growth and development in response to changes in these variables and thus, have to sense the dynamics of the environment and to integrate these signals for an appropriate response. Hence, plants have evolved large number of receptors called receptor-like kinases (RLKs) which have the serine/threonine kinase signature. For instance based on the genome sequence there are over 610 RLK genes in the Arabidopsis genome. Only for a few of the RLKs a physiological role has been established. In the recent years, many different roles have been assigned to several RLKs. So far, only a few RLKs such as BAK1, SRK, BRI1, CLV1, and FLS2 have been studied extensively. RLKs are involved in many different biological processes such as meristem and flower development, stomatal differentiation, self-incompatibility, and plant-microbe interactions. The large numbers of RLK genes in plant genomes and the very diverse structure of the extracellular domain potentially allows them to respond to a wide range of internal and external signals. However, basic important questions for most of the RLKs remain to be answered. Potentially, this knowledge will provide us with the possibility of manipulating the plant sensory system with many implications for experimental or biotechnological purposes.