Daub H, Gevaert K, Vandekerckhove J, Sobel A, Hall A
Medical Research Council Laboratory for Molecular Cell Biology, Cancer Research Campaign Oncogene and Signal Transduction Group, and the Department of Biochemistry, University College London, Gower Street, London WC1E 6BT, United Kingdom.
J Biol Chem. 2001 Jan 19;276(3):1677-80. doi: 10.1074/jbc.C000635200. Epub 2000 Oct 31.
We have identified a rapid protein phosphorylation event at residue serine 16 of stathmin using two-dimensional gel electrophoresis coupled to matrix-assisted laser desorption/ionization mass spectrometry in combination with post-source decay analysis, which is induced by the epidermal growth factor receptor. Phosphorylation is specifically mediated by the small GTPases Rac and Cdc42 and their common downstream target, the serine/threonine kinase p65PAK. Both GTPases have previously been shown to regulate the dynamics of actin polymerization. Because stathmin destabilizes microtubules, and this process is inhibited by phosphorylation at residue 16, Rac and Cdc42 can potentially regulate both F-actin and microtubule dynamics.
我们通过二维凝胶电泳结合基质辅助激光解吸/电离质谱并结合源后衰变分析，确定了在微管蛋白16位丝氨酸残基处存在快速的蛋白质磷酸化事件，该事件由表皮生长因子受体诱导。磷酸化是由小GTP酶Rac和Cdc42及其共同的下游靶点丝氨酸/苏氨酸激酶p65PAK特异性介导的。先前已证明这两种GTP酶都能调节肌动蛋白聚合的动力学。由于微管蛋白会使微管不稳定，而这一过程在16位残基处的磷酸化会受到抑制，因此Rac和Cdc42可能会潜在地调节F-肌动蛋白和微管的动力学。
