Lateral interactions between protofilaments of the bacterial tubulin homolog FtsZ are essential for cell division.
Lateral interactions between protofilaments of the bacterial tubulin homolog FtsZ are essential for cell division.
复制标题
细菌微管蛋白同源物 FtsZ 的原丝之间的横向相互作用对于细胞分裂至关重要
作者：
Guan F;Yu J;Yu J;Liu Y;Li Y;Feng XH;Huang KC;Chang Z;Ye S
原核微管蛋白同源物FtsZ聚合成原丝，其在未来的分裂位点进一步组装成更高级的结构以形成Z环，这是细菌细胞分裂所必需的动态结构。组织Z环的FtsZ原丝之间相互作用的确切性质及其生理意义仍然是个谜。在这项研究中，我们解决了两个晶体结构的一对FtsZ原丝，并证明他们组装在一个反平行的方式，通过形成两个不同的inter-protofilament横向接口。我们的体内光交联研究证实，这种横向相互作用发生在活细胞中，横向相互作用的破坏使细胞无法分裂。固有的弱横向相互作用使FtsZ原丝能够自组织成动态Z环。这些结果对我们理解细菌细胞分裂和开发针对这一关键过程的抗生素具有根本意义。
The prokaryotic tubulin homolog FtsZ polymerizes into protofilaments, which further assemble into higher-order structures at future division sites to form the Z-ring, a dynamic structure essential for bacterial cell division. The precise nature of interactions between FtsZ protofilaments that organize the Z-ring and their physiological significance remain enigmatic. In this study, we solved two crystallographic structures of a pair of FtsZ protofilaments, and demonstrated that they assemble in an antiparallel manner through the formation of two different inter-protofilament lateral interfaces. Our in vivo photocrosslinking studies confirmed that such lateral interactions occur in living cells, and disruption of the lateral interactions rendered cells unable to divide. The inherently weak lateral interactions enable FtsZ protofilaments to self-organize into a dynamic Z-ring. These results have fundamental implications for our understanding of bacterial cell division and for developing antibiotics that target this key process.