FORT COLLINS--A Colorado State University researcher will join colleagues in Germany in using laser microscopy to track protein molecules on the surface of cells, research that may eventually lead to an understanding of how the immune system combats disease.

George Barisas, professor of chemistry and microbiology, has developed techniques that can follow the movement of protein molecules on an immune system cell's surface. The joint research will seek to answer an important question: does a particular kind of protein, called an "antigen presenting" molecule, exist in certain places on a cell membrane or does it move there in response to some chemical signal? The answer could have important implications for how the body fights infection.

Barisas will conduct his collaborative research under the auspices of a 1999 Humboldt Award, a number of which are given annually by vote of German scholars and scientists. Barisas' prize will enable him to work with long-time collaborator Thomas M. Jovin, head of the Department of Molecular Biology at the Max Planck Institute of Biophysical Chemistry in Güttingen.

According to Barisas, current thinking in biology has "lipid rafts"--a lipid is a fat-like substance--floating on the cell's surface. The rafts are lighter than the surrounding membrane. Proteins that normally are distributed across the cell membrane clump together in response to certain stimuli, and, when they do, these clumps seem to move into the rafts. That, in turn, creates further signals within the cell.

"The notion is that these signaling molecules all concentrate in those lipid rafts, and that is in fact the current paradigm for (cellular) signaling," Barisas said.

By concentrating on what molecules are found in (or without) the lipid rafts and under what circumstances, he said, "this lipid raft hypothesis allows us to focus attention on a smaller region and a smaller set of molecu
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Contact: David Weymiller
dweymiller@ur.colostate.edu
970-491-6851
Colorado State University
19-Oct-1999