Two EGF molecules contribute additively to stabilization of the EGFR dimer

摘要: Receptor dimerization is generally considered to be the primary signaling event upon binding of a growth factor its receptor at cell surface. Little, however, known about precise molecular details ligand‐induced dimerization, except for studies human hormone (hGH) receptor. We have analyzed epidermal (EGF) extracellular domain (sEGFR) using titration calorimetry, and resulting sEGFR small‐angle X‐ray scattering. EGF induces quantitative formation dimers that contain two molecules. The data obtained from approaches suggest model in which one monomer binds monomer, involves subsequent association monomeric (1:1) EGF‐sEGFR complexes. Dimerization may result bivalent both molecules dimer and/or receptor‐receptor interactions. requirement (possibly bivalent) monomers distinguishes EGF‐induced hGH interferon‐γ receptors, where multivalent single ligand species (either or dimeric) drives oligomerization. proposed suggests possible mechanisms homo‐ heterodimerization EGFR (or erbB) family receptors.