Droms K A, Haley B E, Malkinson A M
Biochem Biophys Res Commun. 1987 Apr 29;144(2):591-7. doi: 10.1016/s0006-291x(87)80007-4.
Photoincorporation of 8N3-[gamma-32P]-GTP into tissue and cell extracts was examined using gel electrophoresis and autoradiography. Decreased photoincorporation into a 45kD band was observed in extracts from mouse lung tumors as compared to normal mouse lung, and in extracts from lung tumor-derived cell lines when compared to isolated bronchiolar epithelial cells. Decreased 45kD photolabelling was also observed in extracts of S49 lymphoma cyc- cells (deficient in Gs alpha, a 45kD GTP binding protein of receptor-coupled adenylate cyclase) when compared to wild type S49 cells. This, and the observation that there was no cholera toxin-catalyzed ADP-ribosylation in the 45kD band of lung tumor extracts, suggests that the 45kD band contains Gs alpha.
利用凝胶电泳和放射自显影技术检测了8N3-[γ-32P]-GTP在组织和细胞提取物中的光掺入情况。与正常小鼠肺组织提取物相比，在小鼠肺肿瘤提取物中观察到45kD条带的光掺入减少；与分离的细支气管上皮细胞相比，在肺肿瘤来源的细胞系提取物中也观察到光掺入减少。与野生型S49细胞相比，在S49淋巴瘤cyc-细胞（缺乏Gsα，一种受体偶联腺苷酸环化酶的45kD GTP结合蛋白）的提取物中也观察到45kD光标记减少。此外，在肺肿瘤提取物的45kD条带中未观察到霍乱毒素催化的ADP-核糖基化，这表明45kD条带含有Gsα。
