Lutkenhaus Joe
Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, Kansas 66160, USA.
Annu Rev Biochem. 2007;76:539-62. doi: 10.1146/annurev.biochem.75.103004.142652.
The positioning of a cytoskeletal element that dictates the division plane is a fundamental problem in biology. The assembly and positioning of this cytoskeletal element has to be coordinated with DNA segregation and cell growth to ensure that equal-sized progeny cells are produced, each with a copy of the chromosome. In most prokaryotes, cytokinesis involves positioning a Z ring assembled from FtsZ, the ancestral homologue of tubulin. The position of the Z ring is determined by a gradient of negative regulators of Z-ring assembly. In Escherichia coli, the Min system consists of three proteins that cooperate to position the Z ring through a fascinating oscillation, which inhibits the formation of the Z ring away from midcell. Additional gradients of negative regulators of FtsZ assembly are used by E. coli and other bacteria to achieve spatial control of Z-ring assembly.
决定细胞分裂平面的细胞骨架元件的定位是生物学中的一个基本问题。这种细胞骨架元件的组装和定位必须与DNA分离和细胞生长相协调，以确保产生大小相等的子代细胞，每个子代细胞都有一份染色体拷贝。在大多数原核生物中，胞质分裂涉及定位由FtsZ组装而成的Z环，FtsZ是微管蛋白的祖先同源物。Z环的位置由Z环组装负调控因子的梯度决定。在大肠杆菌中，Min系统由三种蛋白质组成，它们通过一种奇妙的振荡协同作用来定位Z环，这种振荡抑制Z环在细胞中部以外的区域形成。大肠杆菌和其他细菌利用FtsZ组装的负调控因子的额外梯度来实现对Z环组装的空间控制。
