The emerging role of Mule and ARF in the regulation of base excision repair

► Mule protein regulates steady state levels of DNA polymerase β, XRCC1 and DNA ligase 3. ► Knockdown of Mule protein leads to elevated rates of DNA repair. ► ARF protein inhibits ubiquitination of DNA polymerase β by Mule. ► Knockdown of ARF protein leads to decreased rates of DNA repair.