A unified theory for intracellular transport to-and-from the cell membrane

Synopsis

Imagine the chaos on the streets if there were no road signs or lights to coordinate traffic. Cells also have traffic routes for transferring molecular cargo to-and-from specific membrane destinations within their interior. However, without some way to coordinate the cellular traffic of lipids and proteins within cells, gridlock would result and growth would come to a standstill. Our research focuses on two important questions about membrane transport within cells: (i) what are the critical molecular parts needed for these transport machines to work; (ii) is there a cellular regulator that coordinates the movement of all these different transport machines? Using Saccharomyces cerevisiae (budding yeast) as a living test tube, our research has identified mechanisms for how sterols like cholesterol are transferred from inside the cell to its outer membrane. We have also discovered a regulatory mechanism that integrates the transport cycle of membrane proteins going to-and-from the cell surface. Through our research we are answering fundamental questions about the dynamics of cell growth, which has direct implications for human health and combating disease.