Defining the molecular basis for associations among glycosphingolipid glycosyltransferases

BIOL 105

Chad M Whitman, firec@stanford.edu, David A. Gross, Cara Beasley, Sandra N Ottensmann, and Jennifer J. Kohler, jjkohler@stanford.edu. Department of Chemistry, Stanford University, 380 Roth Way, Keck Building Room #363, Stanford, CA 94305
Glycosyltransferases residing in the Golgi are responsible for the synthesis of glycosphingolipids, essential components of the plasma membrane. These enzymes are believed to assort with one another, forming biosynthetic clusters. Previous work has indicated that associations among these enzymes are controlled by their N-terminal regions, which include single-pass transmembrane (TM) domains. To characterize interactions among the TM domains of five glycosphingolipid glycosyltransferases, we employed an assay that measures TM domain association in SDS micelles. We discovered that four of the TM domains homo-oligomerize. We have used the same assay to identify the polar and charged amino acids that control oligomerization. In ongoing work, we are employing molecular dynamics simulations, fluorescence spectroscopy and CD spectroscopy to confirm TM domain homo-oligomerization, determine the orientation of the TM domains, and discover TM domain hetero-oligomer formation.
 

Chemistry and Metabolism
4:30 PM-6:30 PM, Tuesday, 12 September 2006 Moscone Center -- Hall D, Poster

Division of Biological Chemistry

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006