Booker G W, Gout I, Downing A K, Driscoll P C, Boyd J, Waterfield M D, Campbell I D
Department of Biochemistry, University of Oxford, England.
Cell. 1993 May 21;73(4):813-22. doi: 10.1016/0092-8674(93)90259-s.
SH3 domains are found in proteins associated with receptor tyrosine kinase signal transduction complexes. The solution structure of the SH3 domain of the 85 kd regulatory subunit of phosphatidylinositol 3-kinase is shown to be a compact beta barrel consisting of five beta strands arranged in two beta sheets of three and two strands. The structure is similar to that of chicken brain alpha spectrin but represents a distinct class of SH3 domain, with an insertion between the second and third beta strands that may influence binding specificity. 1H chemical shift changes induced by complex formation with a synthetic peptide derived from the SH3-binding protein dynamin, together with amino acid sequence comparisons, suggest that the ligand-binding site consists of a hydrophobic surface flanked by two charged loops.
SH3结构域存在于与受体酪氨酸激酶信号转导复合物相关的蛋白质中。磷脂酰肌醇3激酶85 kd调节亚基的SH3结构域的溶液结构显示为一个紧密的β桶，由五条β链组成，排列成两个β片层，一个由三条链组成，另一个由两条链组成。该结构与鸡脑α-血影蛋白的结构相似，但代表了一类独特的SH3结构域，在第二条和第三条β链之间有一个插入片段，可能会影响结合特异性。与源自SH3结合蛋白发动蛋白的合成肽形成复合物所诱导的1H化学位移变化，以及氨基酸序列比较表明，配体结合位点由一个疏水表面组成，两侧是两个带电环。
