Rho-dependent termination and ATPases in transcript termination.

John P Richardson

doi:10.1016/s0167-4781(02)00456-6

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Rho-dependent termination and ATPases in transcript termination.

John P Richardson

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Abstract

Transcription factor Rho is a ring-shaped, homohexameric protein that causes transcript termination through actions on nascent RNAs that are coupled to ATP hydrolysis. The Rho polypeptide has a distinct RNA-binding domain (RNA-BD) of known structure as well as an ATP-binding domain (ATP-BD) for which a structure has been proposed based on homology modeling. A model is proposed in which Rho first makes an interaction with a nascent RNA on a C-rich, primarily single-stranded rut region of the transcript as that region emerges from the exit site of RNA polymerase. A subsequent step involves a temporary release of one subunit of the hexamer to allow the 3' segment of the nascent transcript to enter the central channel of the Rho ring. Actions of the Rho structure in the channel on the 3' segment that are coupled to ATP hydrolysis pull the RNA from its contacts with the template and RNA polymerase, thus causing termination of its synthesis.

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Adenosine Triphosphatases Adenosine Triphosphate Bacterial Proteins DNA-Directed RNA Polymerases Escherichia coli Escherichia coli Proteins Hydrolysis Nucleotides Peptide Chain Termination, Translational Peptide Elongation Factors Protein Structure, Tertiary RNA, Messenger Rho Factor Terminator Regions, Genetic Transcription Factors Transcription, Genetic Journal Article Research Support, U.S. Gov't, P.H.S.Review

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John P Richardson. 2002-09-13. Rho-dependent termination and ATPases in transcript termination.. https://doi.org/10.1016/s0167-4781(02)00456-6

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