Epidermal growth factor (EGF) induces oligomerization of soluble, extracellular, ligand-binding domain of EGF receptor. A low resolution projection structure of the ligand-binding domain.

摘要: Ligand-induced oligomerization is a universal phenomenon among growth factor receptors. Although the mechanism involved yet to be defined, much evidence indicates that receptor plays crucial role in activation and signal transduction. Here we show epidermal (EGF) able stimulate of recombinant, soluble, extracellular ligand-binding domain EGF receptor. Covalent cross-linking experiments, analysis by sodium dodecyl sulfate-gel electrophoresis, size exclusion chromatography, electron microscopy demonstrate dimers, trimers larger multimers are formed response EGF. This establishes an intrinsic property conformational change will receptor-receptor interactions. may bring about allosteric transduction from across plasma membrane, resulting cytoplasmic kinase domain. Electron microscopic images individual domains appear as clusters four similarly-sized stain-excluding areas arranged around central, relatively less stain-excluded area. suggests structurally composed separate domains.