Sorting out membrane traffic with old friends: Having the time of my life at Cal

As a cell biologist and biochemist, Emr's research has focused on uncovering the molecular mechanisms responsible for the biogenesis of a specialized organelle, the lysosome, which functions in the degradation and recycling of cellular proteins, lipids, carbohydrates and nucleic acids. Emr's lab has used a single-cell yeast as a genetic model system to discover and isolate the complex machinery as well as a special class of signaling lipids, phosphoinositides, that sort and deliver proteins and enzymes to lysosomes. This sorting machinery directs the packaging of proteins into small membrane-enclosed carrier vesicles. One set of machines discovered in Emr's lab, the ESCRT complexes, sort and degrade cell surface receptors. ESCRTs comprise a highly conserved set of five protein complexes. Recent studies have identified the ESCRT-III complex as a vesicle budding machine. The ESCRTs also have been found to play an essential role in cytokinesis and the budding and release of the HIV virus from infected cells.

Speaker: Scott Emr, Cornell University