Rad9 (IPR026584)

Short name: Rad9

Overlapping homologous superfamilies


Family relationships


This entry includes DNA damage checkpoint proteins Rad9. Rad9 is required for transient cell-cycle arrests and transcriptional induction of DNA repair in response to DNA damage [PMID: 9755168]. It is worth noting that this entry including the mamalian Rad9, which is homologous to the fission yeast Rad9 and the budding yeast Ddc1. Members of this family do not share the sequence homology with the budding yeast Rad9.

Rad9 forms a complex with Hus1 and Rad1, called 9-1-1 complex. In human, 9-1-1 binds to TopBP1 and activates the ATR-Chk1 checkpoint pathway [PMID: 22925454]. Rad9 also shows 3'-5' exonuclease activity [PMID: 10713044]. Besides its function in the 9-1-1 complex, Rad9 can act as a transcriptional factor, participate in immunoglobulin class switch recombination [PMID: 20729201]. Aberrant Rad9 expression has been associated with prostate, breast, lung, skin, thyroid, and gastric cancers [PMID: 22034047].

GO terms

Biological Process

GO:0000077 DNA damage checkpoint
GO:0006281 DNA repair

Molecular Function

No terms assigned in this category.

Cellular Component

GO:0030896 checkpoint clamp complex

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.