The CLAVATA signaling complex regulates organogenesis in the flowering plant, Arabidopsis. Although several of the components of the CLAVATA complex have been identified and characterized genetically, additional components remain unidentified and/or uncharacterized functionally. Two approaches will be used to identify the new components: a) purification of the proteins using affinity or conventioanl chromatography, and b) analysis of candidate proteins suggested by the known components of the complex. Since a Rho-related GTPase is present, proteins homologous to Rho GTPase effector and target proteins are good candidates for the as-yet-unidentified components. Co- immunoprecipitation experiments will be used to confirm their associations. Identification of a protein component will allow its function to be assessed genetically and biochemically. This project will likely illuminate the CLAVATA complex's signaling mechanism and, potentially, identify its downstream targets. Furthermore, analysis of the Rho GTPase will likely lead to insights into Rho GTPase function in mammals. The human Rho-related GTPase, Rac, is instrumental in Ras- induced malignant transformation, making Rho proteins attractive targets for drugs in cancer treatments.
