2010/AFGN Collaborative Project: The Interaction Network for the Heterotrimeric G-Protein Signaling Pathway

点击翻译按钮获取中文摘要

A variety of signaling networks in Arabidopsis utilize heterotrimeric G-protein complexes to couple signals that are perceived at the cell surface by G-protein coupled receptors (GPCRs) to enzymes called effectors. To date, neither the downstream effectors nor the upstream GPCRs have been unequivocally identified. This paucity of information stands in contrast to human and C. elegans G protein-coupled pathways where 950 GPCRs and more than a dozen effectors have been identified thus representing the most extensive signaling network in metazoans. We will use a high through-put interaction screen to identify proteins that interact with the heterotrimeric G protein complex. Interactors will be tested for in vivo interaction and confirmed candidates will be used as bait to initiate additional rounds of screening. The data will be subjected to bioinformatic and graph-theoretical meta-analyses to identify the main signal transduction pathways and protein complexes (signalosomes) in the interaction network. Selected interactors will be pursued more thoroughly. Reverse genetic and molecular biological approaches will be applied to determine on which branches of the G-protein signaling network these elements operate. Up to 100 genes encoding confirmed interactors will be knocked out either by insertional mutagenesis or via RNAi technique to determine the loss-of-function phenotype. A smaller subset will be pursued in great depth by examining interactions and cellular localization in vivo.