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Space exploration by the promoter of a long human gene during one transcription cycle.

ABSTRACT: An RNA polymerase has been thought to transcribe by seeking out a promoter, initiating and then tracking down the template. We add tumor necrosis factor α to primary human cells, switch on transcription of a 221-kb gene and monitor promoter position during the ensuing transcription cycle (using RNA fluorescence in situ hybridization coupled to super-resolution localization, chromosome conformation capture and Monte Carlo simulations). Results are consistent with a polymerase immobilized in a 'factory' capturing a promoter and reeling in the template, as the transcript and promoter are extruded. Initially, the extruded promoter is tethered close to the factory and so likely to re-initiate; later, the tether becomes long enough to allow re-initiation in another factory. We suggest close tethering underlies enhancer function and transcriptional 'bursting'.

SUBMITTER: Larkin JD

PROVIDER: S-EPMC3575846 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature

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Space exploration by the promoter of a long human gene during one transcription cycle.

Larkin Joshua D JD Papantonis Argyris A Cook Peter R PR Marenduzzo Davide D

Nucleic acids research 20130108 4

An RNA polymerase has been thought to transcribe by seeking out a promoter, initiating and then tracking down the template. We add tumor necrosis factor α to primary human cells, switch on transcription of a 221-kb gene and monitor promoter position during the ensuing transcription cycle (using RNA fluorescence in situ hybridization coupled to super-resolution localization, chromosome conformation capture and Monte Carlo simulations). Results are consistent with a polymerase immobilized in a 'fa ...[more]

PMID: 23303786

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