Jenny Pattison, Brigham Young University
Sensory protein kinases are essential in the phosphorylation of many protein substrates, allowing them to control several metabolic functions and maintain cellular homeostasis. PAS kinase is a sensory protein kinase that is highly conserved and plays a crucial role in glucose homeostasis, however little is known about the molecular mechanisms behind its function. UGP1 is the only well-characterized substrate of PAS kinase, and its phosphorylation diverts glucose away from storage and towards cell wall biosynthesis. We have recently discovered another key substrate of PAS kinase that affects glucose metabolism in the cell, Centromere binding factor 1 (Cbf1). Cbf1 regulates genes involved in respiration, and we have shown that the phosphorylation of Cbf1 by PAS kinase inhibits Cbf1, decreasing respiration in yeast cells. We hypothesize that this is due to a decrease in mitochondrial mass in cbf1 deficient yeast. Further characterizing the effects of PAS kinase on Cbf1 will give further insight into how cells regulate their central metabolic functions, including respiration.