Banting and Best Department of Medical Research

Professor

James D. Friesen

Cross Appointments: Medical Biophysics;

Research Interests:

My colleagues and I use a genetically well-defined eukaryote, the yeast Saccharomyces cerevisiae, as a model for studying aspects of messenger RNA (mRNA) transcription and splicing. We have isolated and characterized many mutations in the genes that encode several subunits of RNA polymerase II, the enzyme that synthesizes all classes of mRNA. Through the study of suppressors and synthetic lethal mutations of these original mutations, we are determining the regions of subunit proteins that are important for interactions with other subunits of the enzyme and with the transcription-elongation factor TFIIS. A second set of projects addresses the structure and function of the spliceosome, the biological apparatus that is responsible for processing mRNA. We have constructed and selected many mutations in the genes that encode three of the small nuclear RNA species and several of the proteins that are essential components of the spliceosome. Analysis of these reveals RNA-RNA and RNA-protein interactions that are important for processing mRNA.