RING finger, HC subclass, found in tumor necrosis factor (TNF) receptor-associated factor 2 (TRAF2) and similar proteins
TRAF2, also known as tumor necrosis factor type 2 receptor-associated protein 3, is an E3 ubiquitin-protein ligase that was identified as a 75 kDa tumor necrosis factor receptor (TNF-R2)-assciated signaling protein. It interacts with members of the TNF receptor superfamily and connects the receptors to downstream signaling proteins. It also mediates K63-linked polyubiquitination of RIP1, a kinase pivotal in TNFalpha-induced NF-kappaB activation. Moreover, TRAF2 regulates peripheral CD8(+) T-cell and NKT-cell homeostasis by modulating sensitivity to IL-15. It also acts an important biological suppressor of necroptosis. It inhibits TNF-related apoptosis inducing ligand (TRAIL)- and CD95L-induced apoptosis and necroptosis. TRAF2 contains an N-terminal domain with a typical C3HC4-type RING-HC finger and several zinc fingers, and a C-terminal TRAF domain that comprises a coiled coil domain and a conserved TRAF-C domain.