Cadena D L, Chan C L, Gill G N
Department of Medicine, University of California, San Diego, La Jolla 92093-0650.
J Biol Chem. 1994 Jan 7;269(1):260-5.
The intracellular portion of the epidermal growth factor receptor consists of a tyrosine kinase domain of approximately 290 amino acids and a COOH-terminal regulatory domain of approximately 230 amino acids that contains five sites of autophosphorylation. The effect of autophosphorylation on the conformation of the intracellular domain has been analyzed using gel filtration. Both phosphorylated and dephosphorylated forms of the intracellular domain exist as monomers and as dimers and appear to have an extended conformation. The Stokes' radii of phosphorylated monomers and dimers were larger than those of the dephosphorylated forms, indicating that the dephosphorylated form is more compact. These results indicate that a significant conformational change occurs in the intracellular portion of the epidermal growth factor receptor upon tyrosine autophosphorylation.
表皮生长因子受体的细胞内部分由一个约290个氨基酸的酪氨酸激酶结构域和一个约230个氨基酸的COOH末端调节结构域组成，该调节结构域含有五个自身磷酸化位点。已使用凝胶过滤分析了自身磷酸化对细胞内结构域构象的影响。细胞内结构域的磷酸化形式和去磷酸化形式均以单体和二聚体形式存在，并且似乎具有伸展的构象。磷酸化单体和二聚体的斯托克斯半径大于去磷酸化形式的斯托克斯半径，表明去磷酸化形式更紧凑。这些结果表明，酪氨酸自身磷酸化后，表皮生长因子受体的细胞内部分发生了显著的构象变化。
