The human checkpoint sensor and alternative DNA clamp Rad9–Rad1–Hus1 modulates the activity of DNA ligase I, a component of the long-patch base excision repair machinery

The human checkpoint sensor and alternative clamp Rad9–Rad1–Hus1 can interact with and specifically stimulate DNA ligase I. The very recently described interactions of Rad9–Rad1–Hus1 with MutY DNA glycosylase, DNA polymerase β and Flap endonuclease 1 now complete our view that the long-patch base excision machinery is an important target of the Rad9–Rad1–Hus1 complex, thus enhancing the quality control of DNA.