Patrick Joyce E, Kearns Daniel B
Department of Biology, Indiana University, Bloomington, IN 47405, USA.
Mol Microbiol. 2008 Dec;70(5):1166-79. doi: 10.1111/j.1365-2958.2008.06469.x. Epub 2008 Oct 2.
In Bacillus subtilis, FtsZ ring formation and cell division is favoured at the midcell because the inhibitor proteins MinC and MinD are indirectly restricted to the cell poles by the protein DivIVA. Here we identify MinJ, a topological determinant of medial FtsZ positioning that acts as an intermediary between DivIVA and MinD. Due to unrestricted MinD activity, cells mutated for minJ exhibited pleiotropic defects in homologous recombination, swarming motility and cell division. MinJ restricted MinD activity by localizing MinD to the cell poles through direct protein-protein interaction. MinJ itself localized to cell poles in a manner that was dependent on DivIVA. MinJ is conserved in other low G+C Gram-positive bacteria and may be an important component of cell division site selection in these organisms.
在枯草芽孢杆菌中，FtsZ环的形成和细胞分裂在细胞中部更为有利，因为抑制蛋白MinC和MinD通过DivIVA蛋白间接被限制在细胞两极。在这里，我们鉴定出MinJ，它是FtsZ定位在中部的拓扑决定因素，在DivIVA和MinD之间起中介作用。由于MinD活性不受限制，minJ基因发生突变的细胞在同源重组、群体运动和细胞分裂方面表现出多效性缺陷。MinJ通过直接的蛋白质-蛋白质相互作用将MinD定位到细胞两极，从而限制MinD的活性。MinJ自身以依赖于DivIVA的方式定位到细胞两极。MinJ在其他低G+C含量的革兰氏阳性细菌中保守，可能是这些生物体中细胞分裂位点选择的重要组成部分。
