RNA polymerase II acts as a selective sensor for DNA lesions and endogenous DNA modifications.

@article{Shin2016RNAPI,
  title={RNA polymerase II acts as a selective sensor for DNA lesions and endogenous DNA modifications.},
  author={Ji Hyun Shin and Liang Xu and Dong Wang},
  journal={Transcription},
  year={2016},
  volume={7 3},
  pages={57-62}
}
During transcription elongation, RNA polymerase II (pol II) travels along the DNA template across thousands to millions of nucleotides and accurately synthesizes the complementary RNA transcripts. Apart from its canonical function as a key enzyme for DNA-dependent RNA synthesis, pol II also functions as a selective sensor to recognize DNA lesions or epigenetic modifications.