Overexpression of the STE4 gene leads to mating response in haploid Saccharomyces cerevisiae
Overexpression of the STE4 gene leads to mating response in haploid Saccharomyces cerevisiae
复制标题
STE4基因的过度表达导致单倍体酿酒酵母的交配反应
DOI：
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发表时间：
1990
影响因子：
5.3
通讯作者：
D. Thomas
中科院分区：
文献类型：
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作者：
M. Whiteway;L. Hougan;D. Thomas
酿酒酵母的STE4基因编码酵母信息素受体偶联G蛋白的β亚基。STE4蛋白的过表达导致单倍体细胞的细胞周期阻滞。这种阻滞类似于由交配信息素介导的阻滞，在阻滞细胞中导致了类似的形态变化。这种阻滞发生在两种交配类型的单倍体细胞中，但在MATa/MAT α二倍体中不发生，它被信息素反应所需的STE12等基因缺陷所抑制。STE4基因产物的过表达也抑制了由STE2和STE3基因编码的交配信息素受体缺陷的细胞的不育性。在过表达SCG1基因产物（G蛋白的α亚基）或缺乏STE18基因产物（G蛋白的γ亚基）的细胞中，STE4过表达介导的细胞周期阻滞被阻止。这一发现表明，在酵母细胞中，β亚基是活性β - γ元素的限制成分，g蛋白亚基水平的适当平衡对正常的交配信息素反应至关重要。
The STE4 gene of Saccharomyces cerevisiae encodes the beta subunit of the yeast pheromone receptor-coupled G protein. Overexpression of the STE4 protein led to cell cycle arrest of haploid cells. This arrest was like the arrest mediated by mating pheromones in that it led to similar morphological changes in the arrested cells. The arrest occurred in haploid cells of either mating type but not in MATa/MAT alpha diploids, and it was suppressed by defects in genes such as STE12 that are needed for pheromone response. Overexpression of the STE4 gene product also suppressed the sterility of cells defective in the mating pheromone receptors encoded by the STE2 and STE3 genes. Cell cycle arrest mediated by STE4 overexpression was prevented in cells that either were overexpressing the SCG1 gene product (the alpha subunit of the G protein) or lacked the STE18 gene product (the gamma subunit of the G protein). This finding suggests that in yeast cells, the beta subunit is the limiting component of the active beta gamma element and that a proper balance in the levels of the G-protein subunits is critical to a normal mating pheromone response.