Our research interests are currently focused on a family of sugar molecules called the
Sialic Acids, and their roles in biology, evolution and disease. The surfaces of all cells in all organisms are decorated with a dense and complex array of sugar chains. These "glycans" are known to mediate or modulate many biological processes including sub-cellular and cellular trafficking, intercellular adhesion, signaling, and microbial attachment. Much data also indicates their involvement in embryonic development, normal tissue organization, tumor metastasis, and in the interactions of cells with extra-cellular molecules. In recent years, improved technologies have permitted exploration of this new frontier of "Molecular Glycobiology."
The Varki lab (directed by Ajit and Nissi Varki) uses these new approaches, along with the traditional tools of molecular biology, biochemistry, genetics and genomics to investigate selected areas of
Glycobiology. The present focus is on
sialic acids, which are found at the outermost position on the glycan chains of all vertebrate cell surfaces and glycoproteins. Currently active projects are relevant to the roles of sialic acids in
Viral and Bacterial Infectivity, the
Regulation of the Immune Response, the
Initiation and Progression of Tumors and
Unique Aspects of Human Evolution. We are particularly intrigued to find multiple differences in sialic acid biology between humans and our closest evolutionary cousins, the great apes. These differences are a signature of the multiple cellular and molecular events that occurred during the last few million years of human evolution, and are relevant to understanding several aspects of the current human condition, both in health and disease.