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Fast transcription rates of RNA polymerase II in human cells.

ABSTRACT: Averaged estimates of RNA polymerase II (RNAPII) elongation rates in mammalian cells have been shown to range between 1.3 and 4.3 kb min(-1). In this work, nascent RNAs from an integrated human immunodeficiency virus type 1-derived vector were detectable at the single living cell level by fluorescent RNA tagging. At steady state, a constant number of RNAs was measured corresponding to a minimal density of polymerases with negligible fluctuations over time. Recovery of fluorescence after photobleaching was complete within seconds, indicating a high rate of RNA biogenesis. The calculated transcription rate above 50 kb min(-1) points towards a wide dynamic range of RNAPII velocities in living cells.

SUBMITTER: Maiuri P

PROVIDER: S-EPMC3245692 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature

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Fast transcription rates of RNA polymerase II in human cells.

Maiuri Paolo P Knezevich Anna A De Marco Alex A Mazza Davide D Kula Anna A McNally Jim G JG Marcello Alessandro A

EMBO reports 20111201 12

Averaged estimates of RNA polymerase II (RNAPII) elongation rates in mammalian cells have been shown to range between 1.3 and 4.3 kb min(-1). In this work, nascent RNAs from an integrated human immunodeficiency virus type 1-derived vector were detectable at the single living cell level by fluorescent RNA tagging. At steady state, a constant number of RNAs was measured corresponding to a minimal density of polymerases with negligible fluctuations over time. Recovery of fluorescence after photoble ...[more]

PMID: 22015688

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