期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1998
卷号：95
期号：4
页码：1523-1527
DOI：10.1073/pnas.95.4.1523
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The subcellular localization of the SopB protein, which is encoded by the Escherichia coli F plasmid and is involved in the partition of the single-copy plasmid, was directly visualized through the expression of the protein fused to the jellyfish green fluorescent protein (GFP). The fusion protein, but not GFP itself, was found to localize to positions close but not at the poles of exponentially growing cells. Neither the presence of other F-encoded proteins nor the binding of SopB to its recognition sites within the sopC locus of F is required for this localization. Examination of derivatives of the fusion protein lacking various regions of SopB suggests that the signal for the cellular localization of SopB resides in a region close to its N terminus. It is plausible that the near polar localization of SopB may serve the function of keeping a segregated pair of F plasmids apart while the cell septum is being formed. The plausible relation between the specific location of SopB and its suppression of sopC-linked genes when overexpressed is also discussed.
关键词：chromosome partitioning ; gene silencing ; green fluorescent protein
