Jensen R B, Wang S C, Shapiro L
Department of Developmental Biology, Beckman Center, Stanford University School of Medicine, Stanford, CA 94305-5329, USA.
EMBO J. 2001 Sep 3;20(17):4952-63. doi: 10.1093/emboj/20.17.4952.
The in vivo intracellular location of components of the Caulobacter replication apparatus was visualized during the cell cycle. Replisome assembly occurs at the chromosomal origin located at the stalked cell pole, coincident with the initiation of DNA replication. The replisome gradually moves to midcell as DNA replication proceeds and disassembles upon completion of DNA replication. Although the newly replicated origin regions of the chromosome are rapidly moved to opposite cell poles by an active process, the replisome appears to be an untethered replication factory that is passively displaced towards the center of the cell by the newly replicated DNA. These results are consistent with a model in which unreplicated DNA is pulled into the replication factory and newly replicated DNA is bidirectionally extruded from the complex, perhaps contributing to chromosome segregation.
在细胞周期中观察到了新月柄杆菌复制装置各组分在体内的细胞内定位。复制体组装发生在位于柄状细胞极的染色体起点处,与DNA复制的起始同时发生。随着DNA复制的进行,复制体逐渐移向细胞中部,并在DNA复制完成时解体。尽管染色体新复制的起点区域通过一个活跃过程迅速移向相对的细胞极,但复制体似乎是一个不受束缚的复制工厂,被新复制的DNA被动地移向细胞中心。这些结果与一个模型相符,即未复制的DNA被拉入复制工厂,新复制的DNA从复合物中双向挤出,这可能有助于染色体分离。