A.B., Mathematics, University of California, Berkeley 1986
Ph.D., Cell Biology, University of California, San Francisco 1993
The Glotzer lab is interested in two, related processes: cytokinesis and cell polarization. Both are controlled by small GTPases and there can be functional interplay between polarization and cytokinesis. These two processes involve the assembly of specialized, dynamic membrane domains in a spatially and temporally controlled manner.
We are interested in determining the spatial and temporal regulation of these events in diverse model systems, including C. elegans, cultured human cells, budding yeast, and Drosophila neuroblasts. We have been focussing on how the key GTPases RhoA and Cdc42 are regulated in space and time, using a combination of forward and reverse genetics, biochemistry, live cell imaging, and increasingly, subcellular optogenetics.
Cytokinesis is mediated by an actin-based contractile ring that is attached to the overlying cell membrane. The contractile ring assembles in the cell cortex after anaphase onset at a site midway between the two poles of the mitotic spindle thereby ensuring that the two sets of chromosomes are equally partitioned into the two daughter cells. Initiation of cytokinesis is driven by the local activation of RhoA, which is mediated by activation of the RhoGEF ECT2, by the multifunctional centralspindlin complex. One major effort is to understand the mechanism by which centralspindlin activates ECT2 and how cortical localization of centralspindlin is regulated. We are also assessing, using optogenetics, whether local activation of RhoA is sufficient to direct cleavage furrow formation.
Likewise, in both budding yeast and Drosophila neuroblasts, we are using optogenetics to experimentally manipulate the pathways that function upstream and downstream of Cdc42 activation during cell polarization.