High rates of actin filament turnover in budding yeast and roles for actin in establishment and maintenance of cell polarity revealed using the actin inhibitor latrunculin-A.
High rates of actin filament turnover in budding yeast and roles for actin in establishment and maintenance of cell polarity revealed using the actin inhibitor latrunculin-A.
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使用肌动蛋白抑制剂 latrunculin-A 揭示了出芽酵母中肌动蛋白丝的高周转率以及肌动蛋白在细胞极性建立和维持中的作用。
DOI：
10.1083/jcb.137.2.399
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发表时间：
1997-04-21
影响因子：
7.8
通讯作者：
Drubin, DG
中科院分区：
文献类型：
--
作者：
Ayscough, KR;Stryker, J;Pokala, N;Sanders, M;Crews, P;Drubin, DG
我们报道，肌动蛋白组装抑制剂拉春库林 - A（LAT - A）在2 - 5分钟内导致酵母肌动蛋白细胞骨架完全瓦解，这表明尽管酵母不能移动，但它们的肌动蛋白丝在体内经历快速的组装和拆卸循环。在肌动蛋白细胞骨架组分中携带突变的菌株对LAT - A的敏感性差异表明，原肌球蛋白、丝束蛋白、封端蛋白、Sla2p和Srv2p的作用是增加肌动蛋白细胞骨架的稳定性，而End3p和Sla1p的作用是降低稳定性。对三个LAT - A抗性肌动蛋白突变体的鉴定表明，LAT - A在体内的作用是由于肌动蛋白功能受损所致，并暗示三维肌动蛋白结构上的一个区域是LAT - A结合位点。
LAT - A被用于确定在细胞极性发育中涉及的19种不同蛋白质中哪些需要肌动蛋白来实现极化定位。结果表明，至少有两种分子途径，一种是肌动蛋白依赖的，另一种是肌动蛋白非依赖的，是极性发育的基础。肌动蛋白依赖途径将分泌小泡和一种假定的小泡对接复合物定位到细胞表面生长位点，这为极化细胞表面生长对肌动蛋白功能的依赖性提供了解释。出乎意料的是，在细胞极性发育过程中与肌动蛋白一起发挥作用的几种蛋白质，包括一种非常规肌球蛋白（Myo2p）、钙调蛋白和一种肌动蛋白相互作用蛋白（Bud6/Aip3p），通过一种肌动蛋白非依赖途径实现极化定位，揭示了细胞极性途径之间的相互依赖性。最后，瞬时肌动蛋白解聚导致许多细胞放弃一个芽位点或交配突起，并在第二个位点开始生长。因此，肌动蛋白丝对于维持细胞极性轴也是必需的。
We report that the actin assembly inhibitor latrunculin-A (LAT-A) causes complete disruption of the yeast actin cytoskeleton within 2–5 min, suggesting that although yeast are nonmotile, their actin filaments undergo rapid cycles of assembly and disassembly in vivo. Differences in the LAT-A sensitivities of strains carrying mutations in components of the actin cytoskeleton suggest that tropomyosin, fimbrin, capping protein, Sla2p, and Srv2p act to increase actin cytoskeleton stability, while End3p and Sla1p act to decrease stability. Identification of three LAT-A resistant actin mutants demonstrated that in vivo effects of LAT-A are due specifically to impairment of actin function and implicated a region on the three-dimensional actin structure as the LAT-A binding site. LAT-A was used to determine which of 19 different proteins implicated in cell polarity development require actin to achieve polarized localization. Results show that at least two molecular pathways, one actindependent and the other actin-independent, underlie polarity development. The actin-dependent pathway localizes secretory vesicles and a putative vesicle docking complex to sites of cell surface growth, providing an explanation for the dependence of polarized cell surface growth on actin function. Unexpectedly, several proteins that function with actin during cell polarity development, including an unconventional myosin (Myo2p), calmodulin, and an actin-interacting protein (Bud6/Aip3p), achieved polarized localization by an actin-independent pathway, revealing interdependence among cell polarity pathways. Finally, transient actin depolymerization caused many cells to abandon one bud site or mating projection and to initiate growth at a second site. Thus, actin filaments are also required for maintenance of an axis of cell polarity.
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DOI：
10.1038/nsb0195-28
发表时间：
1995-01-01
期刊：
NATURE STRUCTURAL BIOLOGY
影响因子：
--
作者：
AMBERG, DC;BASART, E;BOTSTEIN, D
通讯作者：
BOTSTEIN, D
影响因子：
7.8
作者：
DREES, B;BROWN, C;BRETSCHER, A
通讯作者：
BRETSCHER, A
影响因子：
64.8
作者：
FORSCHER, P;LIN, CH;THOMPSON, C
通讯作者：
THOMPSON, C
影响因子：
5.3
作者：
GABER, RF;COPPLE, DM;BARD, M
通讯作者：
BARD, M
影响因子：
7.8
作者：
Field, C;Schekman, R
通讯作者：
Schekman, R