Peter Uetz, J. Craig Venter Institute: "Protein interaction network in bacteria"
Sep 23 2008, 11:00 am
Distinguished Lecture Series Guest Speaker:
J. Craig Venter Institute
Date & Time:Tuesday September 23, 2008
Proteins act by interacting with small chemical compounds and macromolecules, especially other proteins. We have been studying protein-protein interactions with a particular emphasis on proteins of unknown function, assuming that we can learn something about their activities. Recently we finished the protein interaction network of Treponema pallidum which has ~3,600 interactions although the real number may be easily twice as many. I will provide examples from the bacterial flagellar apparatus how these interactions can be used to infer functions of individual proteins. We have also set up genome-wide screens of Streptococcus pneumoniae and Francisella tularensis with additional genomes in the pipeline. Surprisingly there is little overlap between different datasets which can be explained by two main reasons: (1) Yeast two-hybrid (Y2H) screens appear to recover only about a quarter of previously known interactions. (2) These species are sufficiently divergent so that only few interactions are conserved. The low recovery of Y2H screens can be significantly increased by (1) using variations of the method, (2) by screening multiple genomes, and (3) by using protein fragments as opposed to full-length proteins. First results from a comprehensive screen of protein domain interactions show that the function of many domains may be investigated by looking at their structure and interaction patterns.