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The pause-initiation limit restricts transcription activation in human cells

ABSTRACT: Eukaryotic gene transcription is often controlled at the level of RNA polymerase II (Pol II) pausing in the promoter-proximal region. Pausing Pol II limits the frequency of transcription initiation (‘pause-initiation limit’), predicting that the pause duration must be decreased for transcriptional activation. To test this prediction, we conducted a genome-wide kinetic analysis of the heat shock response in human cells. We show that the pause-initiation limit restricts transcriptional activation at most genes. Gene activation generally requires the activity of the P-TEFb kinase CDK9, which decreases the duration of Pol II pausing and thereby enables an increase in the productive initiation frequency. The transcription of enhancer elements is generally not pause-limited and can be activated without CDK9 activity. Our results define the kinetics of Pol II transcriptional regulation in human cells at all gene classes during a natural transcription response.

ORGANISM(S): Homo sapiens

PROVIDER: GSE123980 | GEO | 2019/07/10

REPOSITORIES: GEO

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