Master of Science
Pharmacology and Toxicology
Dr. Peter Chidiac
RGS2 is a GTPase accelerating protein for Gαq and its expression can be upregulated in response to different types of stress. We recently showed that RGS2 can bind to the translation initiation factor, eIF2Bε, and decrease global protein synthesis. The objective of this study is to characterize the RGS2 binding domain of eIF2Bε, and investigate the functional consequences as a result of their interaction. To identify the RGS2 binding domain of eIF2Bε, I generated various truncated eIF2Be-GST fusion proteins and used them in an in vitro pulldown assay. The results of my study revealed that the binding domain lies within the C-terminal region of eIF2Bε, which is consistent with our previous yeast two-hybrid data. A highly conserved amino acid residue within this region (leucine 576) appeared to play an important role in binding to RGS2. In addition, mutating the GSK3 phosphorylation site on eIF2Bε modulated its binding to RGS2. However in my hands, purified eIF2Bε did not inhibit GAP activity of RGS2, contrary to my hypothesis.
Xue, William H., "Characterization of EIF2Be and Its Interaction with RGS2" (2012). University of Western Ontario - Electronic Thesis and Dissertation Repository. Paper 612.