Cell cycle checkpoint protein RAD1 (RAD1)

Cell cycle checkpoint protein RAD1 is a core subunit of the heterotrimeric 9-1-1 clamp complex, which is essential for DNA damage checkpoint activation and DNA repair. Upon sensing DNA damage or replication stress, the 9-1-1 complex (comprising RAD9, RAD1, and HUS1) is loaded onto chromatin by the RAD17 complex, acting as a surveillance platform that recruits and stimulates various DNA repair enzymes. RAD1 plays a regulatory and structural role within the 9-1-1 complex, enabling interactions with DNA polymerases, endonucleases, ligases, and glycosylases involved in multiple DNA repair pathways. Through these functions, RAD1 is critical for maintaining genome stability, preventing cell cycle progression when DNA is damaged, and facilitating accurate DNA repair, particularly during DNA replication and meiosis[1][2][3][4]. Loss or dysfunction of RAD1 can lead to defective DNA damage responses, genomic instability, and is implicated in cancer predisposition syndromes.

Other names

RAD1 checkpoint DNA exonucleaseREC1hRAD1HRAD1Rad1-like DNA damage checkpoint proteinexonuclease homolog RAD1checkpoint control protein HRAD1DNA repair exonuclease REC1RAD1 checkpoint clamp componentRad1 homolog

No direct pharmacological mechanism; the target is not currently drugged, but inhibition or modulation would theoretically affect DNA damage response and repair