MreB actin-mediated segregation of a specific region of a bacterial chromosome.

Department of Developmental Biology, Beckman Center, School of Medicine, Stanford University, California 94305, USA.
Cell (Impact Factor: 33.12). 03/2005; 120(3):329-41. DOI: 10.1016/j.cell.2005.01.007
Source: PubMed

ABSTRACT Faithful chromosome segregation is an essential component of cell division in all organisms. The eukaryotic mitotic machinery uses the cytoskeleton to move specific chromosomal regions. To investigate the potential role of the actin-like MreB protein in bacterial chromosome segregation, we first demonstrate that MreB is the direct target of the small molecule A22. We then demonstrate that A22 completely blocks the movement of newly replicated loci near the origin of replication but has no qualitative or quantitative effect on the segregation of other loci if added after origin segregation. MreB selectively interacts, directly or indirectly, with origin-proximal regions of the chromosome, arguing that the origin-proximal region segregates via an MreB-dependent mechanism not used by the rest of the chromosome.

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