Plants are sessile organisms that must sense and respond quickly and effectively to changes in their environment. The outer membrane of the cell (the plasma membrane) is the interface between the plant cell and its environment, and receptors in this membrane can sense changes in the environment and transmit this information to the cell nucleus to trigger acclimation responses in order to react optimally to the change in conditions. In addition, the plasma membrane is the site where nutrients and metabolites are exchanged (transported) selectively between the cell and its environment. These processes of signal recognition and transport are carried out by thousands of proteins in the plasma membrane, and in order to achieve these functions they directly talk with each other by physical interaction and cooperation with one another in complex ways. These membrane protein interactions (collectively defined as an "interactome") are critically important but not well understood. This project will describe, comprehensively, the membrane protein interactome of the model plant Arabidopsis thaliana and use this information to deduce the structure of the underlying interaction networks. The interactions will be defined and validated using a variety of methods: split ubiquitin and split luciferase assays, as well as a novel microfluidic platform-based assay. The screening pipeline will generate data on over 18 million potential protein interactions, and the data generated will be made publicly available.
Broader Impacts: This project will generate and make available to the research community the most comprehensive membrane protein interactome described for any organism. The project will provide training at the interface between high throughput biology, biochemistry, bioinformatics and cell biology for high school students (including members of minorities under-represented in science), undergraduate students and postdoctoral fellows.
