Elongating RNA polymerase II is disassembled through specific degradation of its largest but not other subunits in response to DNA damage in vivo.
Although previous biochemical studies have demonstrated global degradation of the largest subunit, Rpb1p, of RNA polymerase II in response to DNA damage, it is still not clear whether the initiating or elongating form of Rpb1p is targeted for degradation in vivo. Further, whether other components of RNA polymerase II are degraded in response to DNA damage remains unknown. Here, we show that the Rpb1p subunit of the elongating, but not initiating, form of RNA polymerase II is degraded at the active genes in response to 4-nitroquinoline-1-oxide-induced DNA damage in Saccharomyces cerevisiae. However, other subunits of RNA polymerase II are not degraded in response to DNA damage. Further, we show that Rpb1p is essential for RNA polymerase II assembly at the active gene, and thus, the degradation of Rpb1p following DNA damage disassembles elongating RNA polymerase II. Taken together, our data demonstrate that Rpb1p but not other subunits of elongating RNA polymerase II is specifically degraded in response to DNA damage, and such a degradation of Rpb1p is critical for the disassembly of elongating RNA polymerase II at the DNA lesion in vivo.
Malik
Shivani
S
Department of Biochemistry and Molecular Biology, Southern Illinois University, School of Medicine, Carbondale, Illinois 62901, USA.
Bagla
Shruti
S
Chaurasia
Priyasri
P
Duan
Zhen
Z
Bhaumik
Sukesh R
SR
D015112:4-Nitroquinoline-1-oxide / Q000494:pharmacology; D004249:DNA Damage; D004260:DNA Repair; D015966:Gene Expression Regulation, Fungal; D016681:Genome, Fungal; D008954:Models, Biological; D009153:Mutagens / Q000494:pharmacology; D016366:Open Reading Frames; D012319:RNA Polymerase II / Q000737:chemistry / Q000502:physiology*; D016601:RNA-Binding Proteins / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism; D013997:Time Factors; D014158:Transcription, Genetic; D015533:Transcriptional Activation
D009153:Mutagens; C082119:NGR1 protein, S cerevisiae; D016601:RNA-Binding Proteins; D029701:Saccharomyces cerevisiae Proteins; D015112:4-Nitroquinoline-1-oxide; D012319:RNA Polymerase II