MreB filaments align along greatest principal membrane curvature to orient cell wall synthesis.
MreB filaments align along greatest principal membrane curvature to orient cell wall synthesis.
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DOI：
10.7554/elife.32471
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发表时间：
2018-02-22
期刊：
影响因子：
7.7
通讯作者：
Garner, Ethan C
中科院分区：
文献类型：
--
作者：
Hussain, Saman;Wivagg, Carl N;Garner, Ethan C
MreB对许多细菌的棒状结构至关重要。膜相关的MreB细丝沿着杆的圆周移动，有助于在径向插入细胞壁，以加强杆的形状。为了了解定向MreB运动是如何产生的，我们改变了枯草芽孢杆菌的形状。MreB运动在圆形细胞中是各向同性的，当杆形在外部施加时，方向恢复。固定细丝在原生质体内定向，纯化的MreB管状脂质体在试管内定向。总之，这显示了MreB沿着最大主膜曲率的方向，这一结论得到了生物物理模型的支持。我们观察到球形细胞以局部自我强化的方式再生成杆状细胞：快速繁殖的杆状细胞从小凸起中出现，表现出定向的MreB运动。我们提出，MreB纤维排列与形状增强肽聚糖合成的耦合创造了一种局部作用的自组织机制，允许快速建立和稳定维持紧急棒形状。
MreB is essential for rod shape in many bacteria. Membrane-associated MreB filaments move around the rod circumference, helping to insert cell wall in the radial direction to reinforce rod shape. To understand how oriented MreB motion arises, we altered the shape of Bacillus subtilis. MreB motion is isotropic in round cells, and orientation is restored when rod shape is externally imposed. Stationary filaments orient within protoplasts, and purified MreB tubulates liposomes in vitro, orienting within tubes. Together, this demonstrates MreB orients along the greatest principal membrane curvature, a conclusion supported with biophysical modeling. We observed that spherical cells regenerate into rods in a local, self-reinforcing manner: rapidly propagating rods emerge from small bulges, exhibiting oriented MreB motion. We propose that the coupling of MreB filament alignment to shape-reinforcing peptidoglycan synthesis creates a locally-acting, self-organizing mechanism allowing the rapid establishment and stable maintenance of emergent rod shape.