Katrukha A G, Bereznikova A V, Kochanova N A, Gareeva A B, Popov K M, Bulargina T V, Severin E S
Biokhimiia. 1990 Jul;55(7):1222-8.
The properties of monoclonal antibodies (MA) specifically raised against the alpha-subunit of the GTP-binding protein from bovine brain, G0, were studied. The hybridoma clones were found to secrete MA capable to interact with different antigenic sites of G0 alpha. Clone 1D2 MA interacted with the N-terminal domain of G0 alpha. The antigenic sites for clones 3DE. 1H6 and 2E3 MA were localized in the C-terminal domain of the protein molecule. Using clone 1H6 MA, the site of G0 alpha involved in the interaction with the beta gamma complex located in the C-terminal domain of the alpha-subunit, was revealed. It was found that the interaction of the alpha-subunit with the beta gamma complex changed the conformation of the C-terminal fragment of G0 alpha (Mr5000) together with an increase in the alpha-subunit affinity for clone 2E3 MA. It was concluded that the observed conformational changes may be the reason for the increased affinity of the alpha-subunit for the receptor.
研究了针对牛脑GTP结合蛋白G0的α亚基特异性产生的单克隆抗体（MA）的特性。发现杂交瘤克隆分泌能够与G0α的不同抗原位点相互作用的MA。克隆1D2 MA与G0α的N末端结构域相互作用。克隆3DE、1H6和2E3 MA的抗原位点位于蛋白质分子的C末端结构域。使用克隆1H6 MA，揭示了G0α中与位于α亚基C末端结构域的βγ复合物相互作用的位点。发现α亚基与βγ复合物的相互作用改变了G0α（Mr5000）C末端片段的构象，同时α亚基对克隆2E3 MA的亲和力增加。得出的结论是，观察到的构象变化可能是α亚基对受体亲和力增加的原因。
