The Nonbulky DNA Lesions Spiroiminodihydantoin and 5-Guanidinohydantoin Significantly Block Human RNA Polymerase II Elongation in Vitro.

ABSTRACT: The most common, oxidatively generated lesion in cellular DNA is 8-oxo-7,8-dihydroguanine, which can be oxidized further to yield highly mutagenic spiroiminodihydantoin (Sp) and 5-guanidinohydantoin (Gh) in DNA. In human cell-free extracts, both lesions can be excised by base excision repair and global genomic nucleotide excision repair. However, it is not known if these lesions can be removed by transcription-coupled DNA repair (TCR), a pathway that clears lesions from DNA that impede RNA synthesis. To determine if Sp or Gh impedes transcription, which could make each a viable substrate for TCR, either an Sp or a Gh lesion was positioned on the transcribed strand of DNA under the control of a promoter that supports transcription by human RNA polymerase II. These constructs were incubated

SUBMITTER: Kolbanovskiy M 

PROVIDER: S-EPMC5872833 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature