Editors' ChoiceReceptors

Sensitizing Cell-Surface Signaling

STKE  05 Oct 2004:
Vol. 2004, Issue 253, pp. tw358
DOI: 10.1126/stke.2532004tw358

Signaling at the cell surface involves the interaction between cell-surface receptors and extracellular ligands and is often regulated by a process of receptor internalization that will tend to attenuate signaling in the continuing presence of ligand. Partridge et al. present evidence that the glycosylation state of certain receptors is a key factor in regulating their response to ligands because of its effects on the likelihood of receptor internalization. When a Golgi enzyme responsible for adding specific sugars to cell-surface receptors is upregulated in carcinomas, sensitivity to a variety of growth factors and cytokines is increased. It seems that the receptors become cross-linked together at the cell surface through the expression of the binding site for an endogenous lectin, Gal-3, and that this cell-surface web of receptors resists internalization, thereby prolonging responsiveness to growth factors.

E A. Partridge, C. Le Roy, G. M. Di Guglielmo, J. Pawling, P. Cheung, M. Granovsky, I. R. Nabi, J. L. Wrana, J. W. Dennis, Regulation of cytokine receptors by Golgi N-glycan processing and endocytosis. Science 306, 120-124 (2004) [Abstract] [Full Text]