Membranes & Sorting

BIOGRAPHY

The basic unit of life is the single cell and understanding how living organisms function ultimately requires learning how the parts of a cell work together. The components of cells are made in a few locations and then transported to other places where they function and then to yet other locations for disposal. This requires a complex traffic of molecules within the cell, even in a simple cell such as a bacterium. Animal cells are far more complicated than bacteria and are compartmentalized into a number of distinct organelles; each separated from the others by a limiting membrane. The traffic of the lipids and proteins that make up these membranes is exceedingly complex and involves the exchange of small membrane vesicles between organelles. The focus of my laboratory is to understand how these vesicles are formed and how they select the right cargo. We use recombinant DNA technology to make mutant proteins that we introduce into cells to see how they are recognized and transported within the cell. We rely upon a variety of biochemical techniques as well as light and electron microscopy to locate proteins within cells. We use genetics and biochemistry to identify cellular proteins required for the intracellular traffic of membrane proteins and lipids. Because intracellular membrane traffic is very fast, occurring on a time scale of seconds to minutes, we have started a new initiative to look for fast-acting small molecules that can diffuse into cells and inhibit or stimulate membrane traffic. A current focus of our laboratory is on mechanisms of membrane traffic that are altered in, and contribute to, cancer.