Selectively Seeing Sugars

Science's STKE  11 Dec 2001:
Vol. 2001, Issue 112, pp. tw456
DOI: 10.1126/stke.2001.112.tw456

Cells use surface receptors to sense their surroundings. Although many of the best-characterized receptors detect the presence of small molecules, such as adrenaline, equally important functions are subserved by receptors that interact transiently (or loosely) with environmental macromolecules, either located on other cells or within the extracellular matrix. Feinberg et al. present the crystal structures of two such receptors, DC-SIGN [dendritic cell specific intracellular adhesion molecule-3 (ICAM-3) grabbing nonintegrin] and a related receptor, DC-SIGNR, that recognize carbohydrate moieties of macromolecules. DC-SIGN grabs onto ICAM-3, a surface molecule expressed by T cells, and this interaction forms part of the process of dendritic cell activation of T cells. DC-SIGNR is an endothelial cell component that may mediate the initial stages by which circulating cells scan the surfaces of capillaries and lymph nodes. Both of these receptors are coerced by the human immunodeficiency virus into binding to the HIV protein gp120 before the virus enters T cells.

H. Feinberg, D. A. Mitchell, K. Drickamer, W. I. Weis, Structural basis for selective recognition of oligosaccharides by DC-SIGN and DC-SIGNR. Science 294, 2163-2166 (2001). [Online Journal]