Shibata H, Mukai H, Inagaki Y, Homma Y, Kimura K, Kaibuchi K, Narumiya S, Ono Y
Department of Biology, Faculty of Science, Kobe University, Japan.
FEBS Lett. 1996 May 6;385(3):221-4. doi: 10.1016/0014-5793(96)00385-7.
The yeast two-hybrid system and in vitro binding assay were carried out to characterize the interaction between PKN and a small GTP-binding protein, RhoA. It was revealed that the region corresponding to the amino acid residues 33-111 in the amino-terminal region of PKN was sufficient to confer the ability to associate with RhoA. Each synthetic peptide fragment corresponding to the amino acid residues 74-93 and 94-113 of PKN inhibited the interaction between PKN and RhoA in the in vitro binding assay, suggesting that this region is important in the association with RhoA. The endogenous and the GAP-stimulated GTPase activity of RhoA was inhibited by the interaction with PKN, suggesting the presence of a regulatory mechanism that sustains the GTP-bound active form of RhoA.
采用酵母双杂交系统和体外结合试验来表征蛋白激酶N（PKN）与小GTP结合蛋白RhoA之间的相互作用。结果显示，PKN氨基末端区域中对应于氨基酸残基33 - 111的区域足以赋予与RhoA结合的能力。在体外结合试验中，对应于PKN氨基酸残基74 - 93和94 - 113的每个合成肽片段均抑制了PKN与RhoA之间的相互作用，表明该区域在与RhoA的结合中很重要。RhoA的内源性和GAP刺激的GTP酶活性被与PKN的相互作用所抑制，这表明存在一种维持RhoA的GTP结合活性形式的调节机制。
