| Communication between cells and between the organism and the environment is essential for a multicellular organism. This requires a multitude of signalling pathways as indicated by the predicted existence of several hundreds of transmembrane receptor kinases in the Arabidopsis thaliana genome. Only a very small number of recptor - ligand combinations have been determined. This project is focused on identification of the ligand for the Arabidopsis thaliana Somatic Embryogenesis Receptor Kinase 1 (AtSERK) gene. The AtSERK1 gene belongs to a small family of 5 related genes that is a part of the larger super family of leucin-rich-repeat (LRR)-containing serine- threonine receptor kinases. Ligands will be identified with the aid of an in vivo receptor-activation assay. It will also be determined whether such ligands belong to the group of classical growth regulators in plants such as auxin or cytokinin. The second aim is to use a biochemical and cell biological approach to determine the composition of the AtSERK signalling complexes in living cells. For this will make use of both immunocytological techniques and fluorescently labeled receptors. Using this combined approach, we will be able to visualize the dynamics in living cells of receptor activation and interaction with other proteins of the AtSERK signalling complex. |
