Hara Keisuke, Inada Yuko, Ono Takuya, Kuroda Kouichi, Yasuda-Kamatani Yoshimi, Ishiguro Masaji, Tanaka Takaharu, Misaka Takumi, Abe Keiko, Ueda Mitsuyoshi
Japan Society for the Promotion of Science, Sakyo-ku, Kyoto, Japan.
Biosci Biotechnol Biochem. 2012;76(3):512-6. doi: 10.1271/bbb.110820.
Despite many recent studies of G-protein-coupled receptor (GPCR) structures, it is not yet well understood how these receptors activate G proteins. The GPCR assay using baker's yeast, Saccharomyces cerevisiae, is an effective experimental model for the characterization of GPCR-Gα interactions. Here, using the yeast endogenous Gα protein (Gpa1p) as template, we constructed various chimeric Gα proteins with a region that is considered to be necessary for interaction with mammalian receptors. The signaling assay using the yeast pheromone receptor revealed that the chimeric Gα protein harboring 37 gustducin-specific amino acid residues at its C-terminus (GPA1/gust37) maintained functionality in yeast. In contrast, GPA1/gust44, a variant routinely used in mammalian experimental systems, was not functional.
尽管最近对G蛋白偶联受体（GPCR）结构进行了许多研究，但这些受体如何激活G蛋白仍未得到充分理解。使用酿酒酵母进行的GPCR检测是表征GPCR-Gα相互作用的有效实验模型。在这里，我们以酵母内源性Gα蛋白（Gpa1p）为模板，构建了各种嵌合Gα蛋白，其具有一个被认为与哺乳动物受体相互作用所必需的区域。使用酵母信息素受体的信号检测表明，在其C末端含有37个味觉传导素特异性氨基酸残基的嵌合Gα蛋白（GPA1/gust37）在酵母中保持了功能。相比之下，在哺乳动物实验系统中常规使用的变体GPA1/gust44没有功能。
