Dissecting the molecular basis of potassium homeostasis in yeast

About This Grant

Project Summary/Abstract: The maintenance of resting membrane potential (Vm) is vital for cell survival. Among all organisms, yeast sustain one of the highest levels of intracellular potassium (K+) and a collapse of this gradient leads to cell death. The regulation of high intracellular [K+], which is crucial for controlling yeast Vm, cell volume, and turgor pressure, is thought to be primarily orchestrated by two proteins, Trk1 and Tok1. Despite their importance for yeast viability, the lack of comprehensive mechanistic investigations into these ‘housekeeping’ K+ transport proteins has impeded progress in this critical field of yeast physiology. The objectives of this proposed research plan are to dissect the molecular basis of Trk1 and Tok1 function using a reductionist approach, focusing on both their structural and functional properties, and to identify potential auxiliary subunits involved in their regulation. Answers to these questions will yield fundamental new insights into yeast physiology and could offer insight into yeast hyphae formation and extension, key processes in Candida albicans pathogenesis. Furthermore, the findings from this study will contribute broader knowledge of eukaryotic K+ leak channel physiology. In summary, our research plan will provide us with fundamental knowledge of Trk1 and Tok1 function, with potential implications for eukaryotic cell biology and human health.