Dr. Bettye Sue Hennington
Assistant Professor of Biology
Tougaloo College
Office: 601-877-6198

Abstract: In the model eukaryote Saccharomyces cerevisiae, cell cycle events are coordinated with constitutive functions like energy generation and duplication of protein mass. The latter processes are stimulated by the Rap1p/Gcr1p/Gcr2p complex, which activates transcription of the genes required for rapid growth; this includes glycolytic and ribosomal protein genes, which are among the most heavily transcribed in the cell. In vivo 32P labeling has shown that Rap1p, Gcr1p, and Gcr2p are all phosphoproteins. Mapping the exact sites of phosphorylation in these proteins and identifying the responsible kinases would represent an important advance in our understanding of the signaling cascade(s) that regulates the Rap1 activation complex. I will use tandem mass spectrometry (LC-MS/MS) to analyze phosphorylation sites in these factors.