The filament-forming protein Pil1 assembles linear eisosomes in fission yeast.
The filament-forming protein Pil1 assembles linear eisosomes in fission yeast.
复制标题
形成细丝的蛋白质PIL1在裂变酵母中聚集了线性遗体。
DOI：
10.1091/mbc.e11-07-0605
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发表时间：
2011-11
影响因子：
3.3
通讯作者：
Moseley JB
中科院分区：
文献类型：
--
作者：
Kabeche R;Baldissard S;Hammond J;Howard L;Moseley JB
酶体在酵母细胞的质膜上产生空间结构域。核心核同位体蛋白Pil1在体外和细胞中形成细丝。Pil1丝在细胞皮层稳定，胞质中出现过表达的Pil1丝棒。这显示了自组装在组织皮层结构域中的作用。皮质细胞骨架介导一系列细胞活动，如胞吞作用、细胞运动和细胞刚性的维持。传统的聚合物，包括肌动蛋白、微管和septin，有助于皮质细胞骨架，但也可能存在额外的丝系统。在酵母细胞中，被称为酶体的皮质结构产生被称为mcc的特殊结构域，在膜内陷的位置聚集特定的蛋白质。在这里，我们展示了核心核同体蛋白Pil1在裂变酵母细胞中形成线状皮质细丝，纯化的Pil1在体外组装成细丝。在细胞中，Pil1皮质丝被排除在细胞生长区域之外，独立于肌动蛋白和微管细胞骨架。延时显微镜和光漂白后的荧光恢复显示，Pil1细丝在细胞皮层组装缓慢，且稳定。这种稳定性不需要细胞壁，但Pil1和跨膜蛋白Fhn1共定位并且相互依赖以定位到皮质细丝。Pil1表达的增加导致细胞质中Pil1棒稳定且跨越圆柱形裂变酵母细胞的长度。我们认为Pil1是酵母细胞骨架的一个新组成部分，这可能与细胞空间组织中纤维组装的作用有关。
Eisosomes generate spatial domains in the plasma membrane of yeast cells. The core eisosome protein Pil1 is shown to form filaments in vitro and in cells. Pil1 filaments are stable at the cell cortex, and cytoplasmic Pil1 filament rods appear upon overexpression. This shows a role for self-assembly in organizing cortical domains. The cortical cytoskeleton mediates a range of cellular activities such as endocytosis, cell motility, and the maintenance of cell rigidity. Traditional polymers, including actin, microtubules, and septins, contribute to the cortical cytoskeleton, but additional filament systems may also exist. In yeast cells, cortical structures called eisosomes generate specialized domains termed MCCs to cluster specific proteins at sites of membrane invaginations. Here we show that the core eisosome protein Pil1 forms linear cortical filaments in fission yeast cells and that purified Pil1 assembles into filaments in vitro. In cells, Pil1 cortical filaments are excluded from regions of cell growth and are independent of the actin and microtubule cytoskeletons. Pil1 filaments assemble slowly at the cell cortex and appear stable by time-lapse microscopy and fluorescence recovery after photobleaching. This stability does not require the cell wall, but Pil1 and the transmembrane protein Fhn1 colocalize and are interdependent for localization to cortical filaments. Increased Pil1 expression leads to cytoplasmic Pil1 rods that are stable and span the length of cylindrical fission yeast cells. We propose that Pil1 is a novel component of the yeast cytoskeleton, with implications for the role of filament assembly in the spatial organization of cells.