The protein encoded by this gene regulates the DNA damage response through several different signaling pathways. One such pathway is the p53-HDM2-p21(WAF1) pathway, which is critical to the DNA damage response. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Nov 2015] see less The protein encoded by this gene regulates the DNA damage response through several different signaling pathways. One such pathway is the p53-HDM2-p21(WAF1) pathway, which is critical to the DNA damage response. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Nov 2015]