Receptor Imaging

Visualizing the First Steps of EGR-Receptor Interactions

Science's STKE  14 Mar 2000:
Vol. 2000, Issue 23, pp. tw4
DOI: 10.1126/stke.2000.23.tw4

The initiation of signal transduction by receptor tyrosine kinases involves receptor dimerization and autophosphorylation followed by activation of downstream components. Sako et al. used total internal reflection fluorescence microscopy to study the interaction of epidermal growth factor (EGF) with its receptor EGFR at the level of single molecules. Their data suggest that a single EGF can bind to an EGFR dimer and that the second molecule of EGF binds to these preformed dimers. The formation of the EGF2-EGFR2 complex preceded an EGF-stimulated increase in intracellular calcium concentration and was associated with EGFR phosphorylation. Thus, two molecules of EGF bind to the EGFR dimer to initiate signaling.

Sako, Y., Minoguchi, S., and Yanagida, T. (2000) Single-molecule imaging of EGFR signalling on the surface of living cells. Nature Cell Biol. 2: 168-172. [Online Journal]