Dysfunctional MreB inhibits chromosome segregation in Escherichia coli
Dysfunctional MreB inhibits chromosome segregation in Escherichia coli
复制标题
DOI：
10.1093/emboj/cdg504
复制
发表时间：
2003-10-01
期刊：
影响因子：
11.4
通讯作者：
Gerdes, K
中科院分区：
文献类型：
--
作者：
Kruse, T;Moller-Jensen, J;Gerdes, K
原核生物染色体分离的机制尚不清楚。肌动蛋白同源物MreB是杆状原核细胞中的形状决定因子。使用免疫荧光显微镜，我们发现大肠杆菌的MreB形成位于细胞表面下的螺旋丝。流式细胞术和细胞学分析表明，MreB耗竭细胞分离其染色体成对，与染色体凝聚力一致。野生型MreB的过表达抑制细胞分裂，但不干扰染色体分离。过表达的突变形式的MreB抑制细胞分裂，引起异常的MreB丝形态和诱导严重的定位缺陷的类核和oriC和terC染色体区域。染色体末端区域在MreB耗尽的细胞和过表达MreB突变体形式的细胞中出现相干。我们的观察表明，MreB丝参与定向染色体运动和分离。
The mechanism of prokaryotic chromosome segregation is not known. MreB, an actin homolog, is a shape-determining factor in rod-shaped prokaryotic cells. Using immunofluorescence microscopy we found that MreB of Escherichia coli formed helical filaments located beneath the cell surface. Flow cytometric and cytological analyses indicated that MreB-depleted cells segregated their chromosomes in pairs, consistent with chromosome cohesion. Overexpression of wild-type MreB inhibited cell division but did not perturb chromosome segregation. Overexpression of mutant forms of MreB inhibited cell division, caused abnormal MreB filament morphology and induced severe localization defects of the nucleoid and of the oriC and terC chromosomal regions. The chromosomal terminus regions appeared cohered in both MreB-depleted cells and in cells overexpressing mutant forms of MreB. Our observations indicate that MreB filaments participate in directional chromosome movement and segregation.