Adapter molecule that regulates the activation of NF- kappa-B and JNK. Plays a role in the regulation of cell survival and apoptosis. The heterotrimer formed by TRAF1 and TRAF2 is part of a E3 ubiquitin-protein ligase complex that promotes ubiquitination of target proteins, such as MAP3K14. The TRAF1/TRAF2 complex recruits the antiapoptotic E3 protein- ubiquitin ligases BIRC2 and BIRC3 to TNFRSF1B/TNFR2. Homotrimer. Heterotrimer with TRAF2. Interacts with TNFRSF1A/TNFR1, TNFRSF1B/TNFR2, TNFRSF4, TNFRSF5/CD40, TNFRSF8/CD30, TNFRSF9/CD137, TNFRSF11A/RANK, TNFRSF13C, TNFRSF18/AITR, TNFRSF17/BCMA, TNFRSF19/TROY, TNFRSF19L/RELT, XEDAR, EDAR, Epstein-Barr virus BNFL1/LMP-1, TANK/ITRAF, TRAIP and RIPK2. Interacts with BIRC2 and BIRC3 N-terminus; a single BIRC2 or BIRC3 molecule interacts with a heterotrimer formed by TRAF1 and TRAF2. Interacts with NFATC2IP, TRAFD1 and with HIVEP3. Interacts with MAP3K14. 2 isoforms of the human protein are produced by alternative splicing. Note: This description may include information from UniProtKB.