Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

RNA polymerase II transcribes most eukaryotic genes. Photobleaching studies have revealed that living Chinese hamster ovary cells expressing the catalytic subunit of the polymerase tagged with the green fluorescent protein contain a large rapidly exchanging pool of enzyme, plus a smaller engaged fraction; genetic complementation shows this tagged polymerase to be fully functional. We investigated how transcriptional inhibitors--some of which are used therapeutically--affect the engaged fraction in living cells using fluorescence loss in photobleaching; all were used at concentrations that have reversible effects. Various kinase inhibitors (roscovitine, DRB, KM05283, alsterpaullone, isoquinolinesulfonamide derivatives H-7, H-8, H-89, H-9), proteasomal inhibitors (lactacystin, MG132), and an anti-tumour agent (cisplatin) all reduced the engaged fraction; an intercalator (actinomycin D), two histone deacetylase inhibitors (trichostatin A, sodium butyrate), and irradiation with ultra-violet light all increased it. The polymerase proves to be both a sensitive sensor and effector of the response to these inhibitors.

Original publication

DOI

10.1016/j.yexcr.2007.04.036

Type

Journal article

Journal

Exp Cell Res

Publication Date

15/08/2007

Volume

313

Pages

3026 - 3033

Keywords

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine, Animals, Benzazepines, Cell Line, Cisplatin, Cricetinae, Cricetulus, Cross-Linking Reagents, Dactinomycin, Enzyme Inhibitors, Female, Histone Deacetylase Inhibitors, Histone Deacetylases, Indoles, Photobleaching, Proteasome Endopeptidase Complex, Proteasome Inhibitors, Protein Subunits, Protein Synthesis Inhibitors, RNA Polymerase II, Recombinant Fusion Proteins, Transcription, Genetic, Ultraviolet Rays