Imazumi K, Sasaki T, Takahashi K, Takai Y
Department of Molecular Biology and Biochemistry, Osaka University Medical School, Japan.
Biochem Biophys Res Commun. 1994 Dec 15;205(2):1409-16. doi: 10.1006/bbrc.1994.2822.
Rabphilin-3A is a putative target protein for Rab3A small GTP-binding protein which is implicated in neurotransmitter release. To identify a Rabphilin-3A-interacting protein, proteins were immunoprecipitated by an anti-Rabphilin-3A polyclonal antibody from the lysate of PC12 cells and subjected to sodium dodecyl sulfate polyacrylamide gel electrophoresis followed by protein staining. Several proteins were coimmunoprecipitated with Rabphilin-3A and one of these proteins with a M(r) of about 30 KDa was phosphorylated in intact PC12 cells stimulated by high KCl. The amino acid sequence analysis of this 30 KDa protein revealed that it is GTP cyclohydrolase I.
Rabphilin-3A是Rab3A小GTP结合蛋白的一种假定靶蛋白，该小GTP结合蛋白与神经递质释放有关。为了鉴定与Rabphilin-3A相互作用的蛋白，用抗Rabphilin-3A多克隆抗体从PC12细胞裂解物中免疫沉淀蛋白，然后进行十二烷基硫酸钠聚丙烯酰胺凝胶电泳，随后进行蛋白质染色。几种蛋白与Rabphilin-3A共免疫沉淀，其中一种分子量约为30 kDa的蛋白在高钾刺激的完整PC12细胞中被磷酸化。对这种30 kDa蛋白的氨基酸序列分析表明它是GTP环化水解酶I。
