ISOLATION OF A 2ND YEAST SACCHAROMYCES-CEREVISIAE GENE (GP A2) CODING FOR GUANINE NUCLEOTIDE-BINDING REGULATORY PROTEIN - STUDIES ON ITS STRUCTURE AND POSSIBLE FUNCTIONS
ISOLATION OF A 2ND YEAST SACCHAROMYCES-CEREVISIAE GENE (GP A2) CODING FOR GUANINE NUCLEOTIDE-BINDING REGULATORY PROTEIN - STUDIES ON ITS STRUCTURE AND POSSIBLE FUNCTIONS
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DOI：
10.1073/pnas.85.5.1374
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发表时间：
1988-03-01
影响因子：
11.1
通讯作者：
KAZIRO, Y
中科院分区：
文献类型：
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作者：
NAKAFUKU, M;OBARA, T;KAZIRO, Y
在之前的一篇论文中，我们证明了编码与 .alpha 同源的蛋白质的基因。哺乳动物鸟嘌呤核苷酸结合调节 (G) 蛋白的亚基存在于酿酒酵母中。该基因被命名为 GPA1，编码 472 个氨基酸的蛋白质 (GP1.α.)，计算出的 Mr 为 54,075。在此，我们报道了另一个G蛋白同源基因GPA2的分离，该基因编码449个氨基酸残基的氨基酸序列，Mr为50,516。 GPA2 编码蛋白 (GP2.alpha.) 的预测一级结构与哺乳动物 G 蛋白 [抑制性和刺激性 G 蛋白（分别为 Gi 和 Gs）、功能未知的 G 蛋白 (Go) 和转导蛋白 (Gt)] 以及酵母 GP1.alpha. 是同源的。 Gi (Gi.alpha.)的亚基以获得最大同源性，GP2.alpha。被发现在 NH2 末端附近含有一段额外的 83 个氨基酸残基。该基因被定位在靠近着丝粒的第五号染色体上。携带破坏的 GPA2 基因的单倍体细胞是可行的。携带高拷贝数质粒 GPA2 (YEpGPA2) 的细胞的 cAMP 水平显着升高，并且可以抑制 RAS2 的温度敏感突变。这些结果表明GPA2可能参与酿酒酵母中cAMP水平的调节。
In a previous paper, we demonstrated that a gene coding for a protein homologous to the .alpha. subunit of mammalian guanine nucleotide-binding regulatory (G) proteins occurs in Saccharomyces cerevisiae. The gene, designated GPA1, encodes a protein (GP1.alpha.) of 472 amino acids with a calculated Mr of 54,075. Here we report the isolation of another G-protein-homologous gene, GPA2, which encodes an amino acid sequence of 449 amino acid residues with a Mr of 50,516. The predicted primary structure of the GPA2-encoded protein (GP2.alpha.) is homologous to mammalian G proteins [inhibitory and stimulatory G proteins (Gi and Gs, respectively), a G protein of unknown function (Go), and tranducins (Gt)] as well as yeast GP1.alpha.. When aligned with the .alpha. subunit of Gi (Gi.alpha.) to obtain maximal homology, GP2.alpha. was found to contain a stretch of 83 additional amino acid residues near the NH2 terminus. The gene was mapped in chromosome V, close to the centromere. Haploid cells carrying a disrupted GPA2 gene are viable. Cells carrying a high copy number of plasmid GPA2 (YEpGPA2) had markedly elevated levels of cAMP and could suppress a temperature-sensitive mutation of RAS2. These results suggest that GPA2 may be involved in the regulation of cAMP levels in S. cerevisiae.