Regulates DNA damage response in a dose-dependent manner through a number of signaling pathways involved in cell proliferation, apoptosis and senescence. Interacts with CDKN2A/p14ARF, p53/TP53 and MDM2. Interacts with CHEK2 and MAPK3. Interacts with XRN2 (PubMed:24462208). Ubiquitously expressed. Up-regulated during replicative senescence, in response to DNA-damaging drugs, telomere unprotection and oncogenic Ras-induced stress. Induced by proteasomal inhibitor MG132. Up-regulated at G1 and G2 stages of cell cycle. May be ubiquitinated. Belongs to the CARF family.