Sawitzke J, Austin S
Gene Regulation and Chromosome Biology Laboratory, Division of Basic Sciences, NCI-Frederick, Frederick, MD 21702-1201, USA.
Mol Microbiol. 2001 May;40(4):786-94. doi: 10.1046/j.1365-2958.2001.02350.x.
Recent advances in microscopy have given us important clues as to the nature of chromosome segregation in bacteria. Most current observations favour the view that the process is co-replicational: DNA replication forks are anchored at the cell centre, and the newly replicated DNA is moved towards the cell poles. This scheme can account for orderly segregation even at high growth rates where multiple replication cycles overlap. We argue that there are five distinct activities directly involved in co-replicational segregation dynamics. These we refer to as Push, Direct, Condense, Hold and Clear. We attempt to assign one of these roles to each protein implicated in chromosome segregation. The proposed process is very different from mitosis in eukaryotic cells and perhaps more closely resembles the formation of separate sister chromatids during DNA replication.
显微镜技术的最新进展为我们揭示细菌染色体分离的本质提供了重要线索。目前的大多数观察结果支持这样一种观点，即该过程是共复制性的：DNA复制叉锚定在细胞中心，新复制的DNA向细胞两极移动。即使在多个复制周期重叠的高生长速率下，这种模式也能解释有序分离现象。我们认为，有五种不同的活动直接参与共复制分离动力学。我们将这些活动称为推动、引导、浓缩、保持和清除。我们试图为每一种与染色体分离相关的蛋白质赋予这些角色之一。所提出的过程与真核细胞中的有丝分裂非常不同，可能更类似于DNA复制过程中姐妹染色单体的分离形成。
