An actin-like gene can determine cell polarity in bacteria
An actin-like gene can determine cell polarity in bacteria
复制标题
DOI：
10.1073/pnas.0402638101
复制
发表时间：
2004-06-08
影响因子：
11.1
通讯作者：
Shapiro, L
中科院分区：
文献类型：
--
作者：
Gitai, Z;Dye, N;Shapiro, L
获得适当的极性是细胞功能的关键。在细菌中，通过使用形态和分子标记观察到了细胞极性；然而，还没有确定细菌细胞极性的一般调节因素。在这里，我们调查了两个细胞骨架元素对细胞极性的影响，这两个元素以前与细胞形状决定有关。我们发现，肌动蛋白样的MreB蛋白在新月藻中介导了全局细胞极性，尽管中间的丝状Cres蛋白影响细胞形状，但不影响细胞极性。MreB是以轴向螺旋形式组织的，在细胞周期中动态重新排列，MreB的动力学可能对确定细胞极性至关重要。通过对耗尽和过度表达菌株的研究，我们证明了MreB对于染色体起源序列的极性定位和调节蛋白到正确细胞极点的动态定位都是必需的。我们认为，肌动蛋白样丝固有的分子极性被转化为一种引导全球细胞极性的机制。
Achieving proper polarity is essential for cellular function. In bacteria, cell polarity has been observed by using both morphological and molecular markers; however, no general regulators of bacterial cell polarity have been identified. Here we investigate the effect on cell polarity of two cytoskeletal elements previously implicated in cell shape determination. We find that the actin-like MreB protein mediates global cell polarity in Caulobacter crescentus, although the intermediate filament-like CreS protein influences cell shape without affecting cell polarity. MreB is organized in an axial spiral that is dynamically rearranged during the cell cycle, and MreB dynamics may be critical for the determination of cell polarity. By examining depletion and overexpression strains, we demonstrate that MreB is required both for the polar localization of the chromosomal origin sequence and the dynamic localization of regulatory proteins to the correct cell pole. We propose that the molecular polarity inherent in an actin-like filament is translated into a mechanism for directing global cell polarity.