The Daily Bulletin Archive

Please join the Biology Department, the Great Lakes Center, and the Great Lakes ecosystem science program for the seminar "Harnessing Yeast Genetics for Understanding G-protein-Coupled Receptor Function and for HIV Vaccine Development," presented by Mark E. Dumont, professor of biochemistry and biophysics at the University of Rochester, on Monday, November 20, from 4:00 to 5:15 p.m. in Bulger Communication Center West. All students, staff, and faculty are welcome.

Abstract
This seminar will focus on two projects that are ongoing in our laboratory:

1.  Mechanisms of Signal Transduction by G-protein-Couple Receptors (GPCRs). The large superfamily of G-protein-couple receptors is responsible for responses to diverse physical and chemical stimuli, including sensory stimuli, hormones, and neurotransmitters. These receptors also are targets of a large fraction of all clinically useful drugs; however, many aspects of GPCR signaling remain poorly understood. Our laboratory is investigating signaling by the GPCRs mediating responses to mating pheromone by baker’s yeast Saccharomyces cerevisiae as a model system for understanding GPCR signaling. Since GPCRs generally exist as oligomers, we combine fluorescence-based approaches for detecting receptor-receptor interactions with quantitative measurements of signaling responses by normal and mutant receptors to understand the roles of receptor-receptor interactions in regulation of responses to pheromone binding.
2. Isolation of Variant Forms of HIV Envelope Protein for Use in HIV Vaccine Development. Approximately 20 percent of HIV-infected individuals slowly develop neutralizing antibody responses that are capable of protecting against HIV infection; however, to date, only modest success has been achieved in developing a vaccine capable of eliciting a useful neutralizing antibody response. Part of the reason for this appears to be poor binding of HIV envelope protein to the antibody precursors that is necessary to trigger development of an immune response. To overcome this problem, we have conducted large-scale random mutagenesis of the envelope protein displayed on the surface of yeast cells and isolated variant forms of the envelope protein with enhanced affinity for relevant antibody precursors.