ZipA 和 FtsA*稳定 FtsZ-GDP 小环结构。

ZipA and FtsA* stabilize FtsZ-GDP miniring structures.

机构信息

Key Laboratory of Resources Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi'an, Shaanxi Province, 710069, P.R. China.

Department of Cell Biology, Duke University Medical Center, Durham, NC, 27710, USA.

出版信息

Sci Rep. 2017 Jun 16;7(1):3650. doi: 10.1038/s41598-017-03983-4.

The cytokinetic division ring of Escherichia coli comprises filaments of FtsZ tethered to the membrane by FtsA and ZipA. Previous results suggested that ZipA is a Z-ring stabilizer, since in vitro experiments it is shown that ZipA enhanced FtsZ assembly and caused the filaments to bundles. However, this function of ZipA has been challenged by recent studies. First, ZipA-induced FtsZ bundling was not significant at pH greater than 7. Second, some FtsA mutants, such as FtsA* were able to bypass the need of ZipA. We reinvestigated the interaction of FtsZ with ZipA in vitro. We found that ZipA not only stabilized and bundled straight filaments of FtsZ-GTP, but also stabilized the highly curved filaments and miniring structures formed by FtsZ-GDP. FtsA* had a similar stabilization of FtsZ-GDP minirings. Our results suggest that ZipA and FtsA* may contribute to constriction by stabilizing this miniring conformation.

大肠杆菌的细胞分裂环由通过 FtsA 和 ZipA 连接到膜上的 FtsZ 丝组成。先前的结果表明，ZipA 是 Z 环稳定剂，因为体外实验表明 ZipA 增强了 FtsZ 的组装并导致丝束化。然而，最近的研究对 ZipA 的这一功能提出了挑战。首先，在 pH 值大于 7 时，ZipA 诱导的 FtsZ 束集并不明显。其次，一些 FtsA 突变体，如 FtsA*，能够绕过对 ZipA 的需求。我们重新研究了 FtsZ 与 ZipA 在体外的相互作用。我们发现，ZipA 不仅稳定和束集 FtsZ-GTP 的直丝，还稳定由 FtsZ-GDP 形成的高度弯曲丝和小环结构。FtsA也对 FtsZ-GDP 小环具有类似的稳定作用。我们的结果表明，ZipA 和 FtsA可能通过稳定这种小环构象来促进收缩。