Multiple mechanisms contribute to inhibit transcription in response to DNA damage.
Cellular DNA damage elicits the phosphorylation and ubiquitination of RNA polymerase II (RNAPII), leading to the global repression of transcription. In this report we show that there are at least two different pathways to transcriptional repression, depending on the type of DNA damage. After H2O2 treatment, transcription was rapidly inhibited and rapidly restored. On the other hand, UV irradiation caused a much slower transcriptional inhibition, with a corresponding depletion of unphosphorylated RNAPII. We found that after UV treatment, but not treatment with H2O2, the inhibition of transcription was dependent on both the proteasome and new protein synthesis. In addition, RNAPII activity and ubiquitination were regulated through the phosphorylation of RNAPII by the P-TEFb kinase. These results highlight that multiple cellular pathways exist to globally repress transcriptional processes that might interfere with the repair of DNA damage.
Heine
George F
GF
Department of Biomedical Informatics and the Comprehensive Cancer Center, Ohio State University, Columbus, OH 43210, USA.
Horwitz
Andrew A
AA
Parvin
Jeffrey D
JD
D004249:DNA Damage / Q000187:drug effects* / Q000528:radiation effects*; D004260:DNA Repair / Q000187:drug effects / Q000528:radiation effects; D006367:HeLa Cells; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D016877:Oxidants / Q000494:pharmacology*; D010766:Phosphorylation / Q000187:drug effects / Q000528:radiation effects; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism; D014176:Protein Biosynthesis / Q000187:drug effects* / Q000528:radiation effects*; D012319:RNA Polymerase II / Q000378:metabolism*; D014158:Transcription, Genetic / Q000187:drug effects* / Q000528:radiation effects*; D054875:Ubiquitination / Q000187:drug effects / Q000528:radiation effects; D014466:Ultraviolet Rays
D016877:Oxidants; D006861:Hydrogen Peroxide; D012319:RNA Polymerase II; D046988:Proteasome Endopeptidase Complex