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Comparative overview of RNA polymerase II and III transcription cycles, with focus on RNA polymerase III termination and reinitiation.

ABSTRACT: In eukaryotes, RNA polymerase (RNAP) III transcribes hundreds of genes for tRNAs and 5S rRNA, among others, which share similar promoters and stable transcription initiation complexes (TIC), which support rapid RNAP III recycling. In contrast, RNAP II transcribes a large number of genes with highly variable promoters and interacting factors, which exert fine regulatory control over TIC lability and modifications of RNAP II at different transitional points in the transcription cycle. We review data that illustrate a relatively smooth continuity of RNAP III initiation-elongation-termination and reinitiation toward its function to produce high levels of tRNAs and other RNAs that support growth and development.

SUBMITTER: Arimbasseri AG

PROVIDER: S-EPMC4214234 | biostudies-literature | 2014 Jan-Mar

REPOSITORIES: biostudies-literature

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Comparative overview of RNA polymerase II and III transcription cycles, with focus on RNA polymerase III termination and reinitiation.

Arimbasseri Aneeshkumar G AG Rijal Keshab K Maraia Richard J RJ

Transcription 20140101 1

In eukaryotes, RNA polymerase (RNAP) III transcribes hundreds of genes for tRNAs and 5S rRNA, among others, which share similar promoters and stable transcription initiation complexes (TIC), which support rapid RNAP III recycling. In contrast, RNAP II transcribes a large number of genes with highly variable promoters and interacting factors, which exert fine regulatory control over TIC lability and modifications of RNAP II at different transitional points in the transcription cycle. We review da ...[more]

PMID: 25764110

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