FAR1 is required for oriented polarization of yeast cells in response to mating pheromones.
FAR1 is required for oriented polarization of yeast cells in response to mating pheromones.
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DOI：
10.1083/jcb.131.4.863
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发表时间：
1995-11
期刊：
影响因子：
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通讯作者：
Herskowitz I
中科院分区：
文献类型：
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作者：
Valtz N;Peter M;Herskowitz I
细胞极化包括在细胞表面指定一个区域，并组织细胞骨架朝向该标志。外部信号被转换成内部标志的极化机制知之甚少。酵母酿酒酵母在交配过程中表现出极化生长：每个细胞的肌动蛋白细胞骨架向其伴侣极化，可能是为了实现有效的细胞融合。外部信号决定了极化的标志，被认为是一个梯度的肽信息素释放的交配伙伴。在这里，我们描述了表现出随机极化的突变体。使用两种测定，包括用于定向的直接显微镜测定（Segall，J. 1993. Proc. Natl. Acad. Sci. USA. 90：8332- 8337），我们表明这些突变体不能定位信息素梯度的来源，尽管它们能够组织它们的细胞骨架。这些突变体似乎在交配中有缺陷，因为它们无法找到交配伴侣。它们携带FAR 1基因的突变，表示为far 1-s，并确定了Far 1蛋白的新功能。其另一已知功能是通过抑制细胞周期蛋白依赖性激酶在交配期间促进细胞周期停滞（Peter，M.，和I. Herskowitz 1994.科学（Wash）DC）。265：1228-1232）。far 1-S突变体表现出正常的细胞周期阻滞响应信息素，这表明，Far 1蛋白在交配中起着两个不同的作用：一个在细胞周期阻滞和其他在朝向交配伴侣的方向。
Cell polarization involves specifying an area on the cell surface and organizing the cytoskeleton towards that landmark. The mechanisms by which external signals are translated into internal landmarks for polarization are poorly understood. The yeast Saccharomyces cerevisiae exhibits polarized growth during mating: the actin cytoskeleton of each cell polarizes towards its partner, presumably to allow efficient cell fusion. The external signal which determines the landmark for polarization is thought to be a gradient of peptide pheromone released by the mating partner. Here we described mutants that exhibit random polarization. Using two assays, including a direct microscope assay for orientation (Segall, J. 1993. Proc. Natl. Acad. Sci. USA. 90:8332- 8337), we show that these mutants cannot locate the source of a pheromone gradient although they are able to organize their cytoskeleton. These mutants appear to be defective in mating because they are unable to locate the mating partner. They carry mutations of the FAR1 gene, denoted far1-s, and identify a new function for the Far1 protein. Its other known function is to promote cell cycle arrest during mating by inhibiting a cyclin-dependent kinase (Peter, M., and I. Herskowitz. 1994. Science (Wash. DC). 265:1228-1232). The far1-s mutants exhibit normal cell cycle arrest in response to pheromone, which suggests that Far1 protein plays two distinct roles in mating: one in cell cycle arrest and the other in orientation towards the mating partner.