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A Cre Transcription Fidelity Reporter Identifies GreA as a Major RNA Proofreading Factor in Escherichia coli.

ABSTRACT: We made a coupled genetic reporter that detects rare transcription misincorporation errors to measure RNA polymerase transcription fidelity in Escherichia coli Using this reporter, we demonstrated in vivo that the transcript cleavage factor GreA, but not GreB, is essential for proofreading of a transcription error where a riboA has been misincorporated instead of a riboG. A greA mutant strain had more than a 100-fold increase in transcription errors relative to wild-type or a greB mutant. However, overexpression of GreB in ?greA cells reduced the misincorporation errors to wild-type levels, demonstrating that GreB at high concentration could substitute for GreA in RNA proofreading activity in vivo.

SUBMITTER: Bubunenko MG

PROVIDER: S-EPMC5419468 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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A Cre Transcription Fidelity Reporter Identifies GreA as a Major RNA Proofreading Factor in Escherichia coli.

Bubunenko Mikhail G MG Court Carolyn B CB Rattray Alison J AJ Gotte Deanna R DR Kireeva Maria L ML Irizarry-Caro Jorge A JA Li Xintian X Jin Ding J DJ Court Donald L DL Strathern Jeffrey N JN Kashlev Mikhail M

Genetics 20170324 1

We made a coupled genetic reporter that detects rare transcription misincorporation errors to measure RNA polymerase transcription fidelity in Escherichia coli Using this reporter, we demonstrated in vivo that the transcript cleavage factor GreA, but not GreB, is essential for proofreading of a transcription error where a riboA has been misincorporated instead of a riboG. A greA mutant strain had more than a 100-fold increase in transcription errors relative to wild-type or ...[more]

PMID: 28341651

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