The function of PIDD1 (p53-induced death domain protein 1, ENSG00000177595) is as follows. Component of the DNA damage/stress response pathway that functions downstream of p53/TP53 and can either promote cell survival or apoptosis (PubMed:10973264, PubMed:15073321, PubMed:16360037, PubMed:17159900). Associated with CRADD and the CASP2 caspase, it forms the PIDDosome a complex that activates CASP2 and triggers apoptosis (PubMed:15073321, PubMed:17159900). Associated with IKBKG and RIPK1, it enhances sumoylation and ubiquitination of IKBKG which is important for activation of the transcription factor NF-kappa-B (PubMed:16360037, PubMed:17159900). {ECO:0000269|PubMed:10973264, ECO:0000269|PubMed:15073321, ECO:0000269|PubMed:16360037, ECO:0000269|PubMed:17159900}.