Transcription bypass of DNA lesions enhances cell survival but attenuates transcription coupled DNA repair

Authors

Wentao Li, Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA.
Kathiresan Selvam, Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA.
Tengyu Ko, Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA.
Shisheng Li, Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA shli@lsu.edu.

Document Type

Article

Publication Date

12-1-2014

Abstract

Transcription-coupled DNA repair (TCR) is a subpathway of nucleotide excision repair (NER) dedicated to rapid removal of DNA lesions in the transcribed strand of actively transcribed genes. The precise nature of the TCR signal and how the repair machinery gains access to lesions imbedded in stalled RNA polymerase II (RNAP II) complexes in eukaryotic cells are still enigmatic. RNAP II has an intrinsic capacity for transcription bypass of DNA lesions by incorporation or misincorporation of nucleotides across the lesions. It has been suggested that transcription bypass of lesions, which exposes the lesions, may be required for TCR. Here, we show that E1103G mutation of Rpb1, the largest subunit of RNAP II, which promotes transcription bypass of UV-induced cyclobutane pyrimidine dimers (CPDs), increases survival of UV irradiated yeast cells but attenuates TCR. The increased cell survival is independent of any NER subpathways. In contrast, G730D mutation of Rpb1, which impairs transcription bypass of CPDs, enhances TCR. Our results suggest that transcription bypass of lesions attenuates TCR but enhances cell tolerance to DNA lesions. Efficient stalling of RNAP II is essential for efficient TCR.

Publication Source (Journal or Book title)

Nucleic acids research

First Page

13242

Last Page

53

Recommended Citation

Li, W., Selvam, K., Ko, T., & Li, S. (2014). Transcription bypass of DNA lesions enhances cell survival but attenuates transcription coupled DNA repair. Nucleic acids research, 42 (21), 13242-53. https://doi.org/10.1093/nar/gku1150