Translational control and differential RNA decay are key elements regulating postsegregational expression of the killer protein encoded by the parB locus of plasmid R1.

K Gerdes; K Helin; O W Christensen; A Løbner-Olesen

doi:10.1016/0022-2836(88)90096-4

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Translational control and differential RNA decay are key elements regulating postsegregational expression of the killer protein encoded by the parB locus of plasmid R1.

K Gerdes·K Helin·O W Christensen·A Løbner-Olesen

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Abstract

The parB locus of plasmid R1, which mediates plasmid stability via postsegregational killing of plasmid-free cells, encodes two genes, hok and sok. The hok gene product is a potent cell-killing protein. The hok gene is regulated at the translational level by the sok gene-encoded repressor, a small anti-sense RNA complementary to the hok mRNA. The hok mRNA is extraordinarily stable, while the sok RNA decays rapidly. The mechanism of postsegregational killing is explained by the following model; the sok RNA molecule rapidly disappears in cells that have lost a parB-carrying plasmid, leading to translation of the stable hok mRNA. Consequently, the Hok protein is synthesized and killing of the plasmid-free cell follows.

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Base Sequence Chromosome Mapping Escherichia coli Gene Expression Regulation Genes, Bacterial Molecular Sequence Data Promoter Regions, Genetic Protein Biosynthesis R Factors RNA, Bacterial RNA, Messenger Rifampin Suppression, Genetic Journal Article Research Support, Non-U.S. Gov't

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K Gerdes, K Helin, O W Christensen, A Løbner-Olesen. 1988-09-05. Translational control and differential RNA decay are key elements regulating postsegregational expression of the killer protein encoded by the parB locus of plasmid R1.. https://doi.org/10.1016/0022-2836(88)90096-4

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