Tsujimura K, Tanaka J, Ando S, Matsuoka Y, Kusubata M, Sugiura H, Yamauchi T, Inagaki M
Department of Neurophysiology, Tokyo Metropolitan Institute of Gerontology.
J Biochem. 1994 Aug;116(2):426-34. doi: 10.1093/oxfordjournals.jbchem.a124542.
We identified the phosphorylation sites of glial fibrillary acidic protein (GFAP) for cdc2 kinase and Ca(2+)-calmodulin (CaM)-dependent protein kinase II. GFAP was phosphorylated to approximately 0.2 mol of phosphate/mol of GFAP by cdc2 kinase, and this phosphorylation did not induce disassembly of the filament structure. On the other hand, GFAP was phosphorylated to approximately 1.9 mol of phosphate/mol of GFAP by Ca(2+)-CaM-dependent protein kinase II, and this phosphorylation did induce disassembly of the filament. Sequential analysis of the purified phosphopeptides revealed that only Ser8 on GFAP was phosphorylated by cdc2 kinase, whereas Ser13, Ser17, Ser34, and Ser389 on GFAP were phosphorylated by Ca(2+)-CaM-dependent protein kinase II.
我们确定了神经胶质纤维酸性蛋白(GFAP)上细胞周期蛋白依赖性激酶2(cdc2激酶)和钙/钙调蛋白(Ca2 + -CaM)依赖性蛋白激酶II的磷酸化位点。cdc2激酶使GFAP磷酸化程度达到约0.2摩尔磷酸/摩尔GFAP,且这种磷酸化未诱导丝状结构的解聚。另一方面,Ca2 + -CaM依赖性蛋白激酶II使GFAP磷酸化程度达到约1.9摩尔磷酸/摩尔GFAP,而这种磷酸化确实诱导了丝状结构的解聚。对纯化的磷酸肽进行序列分析表明,cdc2激酶仅使GFAP上的Ser8磷酸化,而Ca2 + -CaM依赖性蛋白激酶II使GFAP上的Ser13、Ser17、Ser34和Ser389磷酸化。