Negative regulator of E2F transcription factors links cell cycle checkpoint and DNA damage repair

Significance DNA is frequently damaged by both endogenous and exogenous factors. In response to DNA damage, cells activate checkpoints to arrest cell cycle progression, allowing sufficient time for DNA repair. Defects in DNA repair cause many diseases including cancers. The E2F transcription factors are key players in cell cycle progression and are negatively regulated by the tumor suppressor protein Retinoblastoma. In this study, we demonstrated that the DNA repair protein SNI1, a subunit of SMC5/6 complex, is a negative regulator of E2Fs. In addition, this study also suggests that checkpoint and DNA repair are directly linked by SNI1, providing insights into DNA damage responses.