Morgan, David, Ph.D.

The lab uses a variety of different model systems, including budding yeast and mammalian cells, to address fundamental questions in the control of cell division by Cdks and other regulatory molecules. Major projects in the lab include the following:

Targets of the Cdks: Little is known about the mechanisms by which Cdks trigger cell-cycle events. It is generally assumed that Cdks, like other protein kinases, exert their effects by phosphorylating target proteins, but few of these target proteins have been identified. The lab uses a novel 'chemical genetic' approach, conceived by our UCSF colleague Kevan Shokat, to search the yeast and vertebrate proteomes for Cdk substrates.

Exit from mitosis: Morgan Lab explores the regulatory mechanisms that complete the cell cycle in late mitosis. Much of this work focuses on a mysterious multi-subunit enzyme called the Anaphase-promoting complex (APC). The APC is a ubiquitin-protein ligase that catalyzes the attachment of the protein ubiquitin to substrate proteins, thereby targeting these substrates for destruction. In late mitosis, the APC triggers the proteolytic destruction of several cell-cycle regulators, including cyclins. The lab is interested in the biochemical reactions catalyzed by the APC and in the regulatory systems that control these reactions.