Targeting of chitin synthase 3 to polarized growth sites in yeast requires Chs5p and Myo2p.
Targeting of chitin synthase 3 to polarized growth sites in yeast requires Chs5p and Myo2p.
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DOI：
10.1083/jcb.136.1.95
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发表时间：
1997-01-13
影响因子：
7.8
通讯作者：
Snyder, M
中科院分区：
文献类型：
--
作者：
Santos, B;Snyder, M
甲壳素是酵母细胞壁的重要结构成分，其沉积在整个酵母生命周期中都受到调节。通过对几丁质合成酶Ⅲ催化亚基Chs3p及其调控因子Chs5p的定位，研究了酿酒酵母营养生长和交配过程中几丁质合成的时空规律。表位标记的Chs3p的免疫定位揭示了一种新的定位模式，即依赖于细胞周期。在小芽细胞中，Chs3p在幼芽部位和母芽之间的颈部被极化为扩散环；在含有单个核的大芽细胞中，Chs3p在颈部没有发现。在进行胞质分裂的大芽细胞中，它在颈部重新出现为一个环。在对交配信息素作出反应的细胞中，Chs3p贯穿整个投射过程。Chs3p在皮质部位的出现与预期几丁质合成的时间相关。Chs3p除定位于幼芽部位和幼芽颈部外，还存在于细胞周期不同阶段的细胞质中。表位标记的Chs5p也定位于细胞质斑块；这些斑块含有Kex2p，一种晚期高尔基体相关酶。与Chs3p不同，Chs5p不会在幼芽部位或颈部积累。几乎所有的Chs3p补丁都含有Chs5p，而一些Chs5p补丁缺少可检测到的Chs3p。在没有Chs5p的情况下，Chs3p定位于细胞质斑块，但不再存在于颈部或萌发部位，这表明Chs5p是Chs3p极化所必需的。此外，Chs5p的定位既不受温度变化的影响，也不受myo2-66突变的影响，而Chs3p的极化受温度变化和myo2-66的影响。我们提出了一个模型，在该模型中，酵母中Chs3p对皮质位置的极化取决于Chs5p和肌动蛋白细胞骨架/Myo2p。
Chitin is an essential structural component of the yeast cell wall whose deposition is regulated throughout the yeast life cycle. The temporal and spatial regulation of chitin synthesis was investigated during vegetative growth and mating of Saccharomyces cerevisiae by localization of the putative catalytic subunit of chitin synthase III, Chs3p, and its regulator, Chs5p. Immunolocalization of epitope-tagged Chs3p revealed a novel localization pattern that is cell cycledependent. Chs3p is polarized as a diffuse ring at the incipient bud site and at the neck between the mother and bud in small-budded cells; it is not found at the neck in large-budded cells containing a single nucleus. In large-budded cells undergoing cytokinesis, it reappears as a ring at the neck. In cells responding to mating pheromone, Chs3p is found throughout the projection. The appearance of Chs3p at cortical sites correlates with times that chitin synthesis is expected to occur. In addition to its localization at the incipient bud site and neck, Chs3p is also found in cytoplasmic patches in cells at different stages of the cell cycle. Epitope-tagged Chs5p also localizes to cytoplasmic patches; these patches contain Kex2p, a late Golgi-associated enzyme. Unlike Chs3p, Chs5p does not accumulate at the incipient bud site or neck. Nearly all Chs3p patches contain Chs5p, whereas some Chs5p patches lack detectable Chs3p. In the absence of Chs5p, Chs3p localizes in cytoplasmic patches, but it is no longer found at the neck or the incipient bud site, indicating that Chs5p is required for the polarization of Chs3p. Furthermore, Chs5p localization is not affected either by temperature shift or by the myo2-66 mutation, however, Chs3p polarization is affected by temperature shift and myo2-66. We suggest a model in which Chs3p polarization to cortical sites in yeast is dependent on both Chs5p and the actin cytoskeleton/Myo2p.
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影响因子：
7.8
作者：
FRANZUSOFF, A;REDDING, K;SCHEKMAN, R
通讯作者：
SCHEKMAN, R
影响因子：
7.8
作者：
ESPENSHADE, P;GIMENO, RE;KAISER, CA
通讯作者：
KAISER, CA
影响因子：
64.8
作者：
AMATRUDA, JF;CANNON, JF;COOPER, JA
通讯作者：
COOPER, JA
DOI：
10.1083/jcb.119.5.1151
发表时间：
1992-12
期刊：
The Journal of cell biology
影响因子：
--
作者：
Amatruda JF;Gattermeir DJ;Karpova TS;Cooper JA
通讯作者：
Cooper JA
DOI：
10.1083/jcb.119.6.1459
发表时间：
1992-12
期刊：
The Journal of cell biology
影响因子：
--
作者：
Cooper A;Bussey H
通讯作者：
Bussey H