SignalSilence^® TRAF5 siRNA I #38805

TRAFs (TNF receptor-associated factors) are a family of multifunctional adaptor proteins that bind to surface receptors and recruit additional proteins to form multiprotein signaling complexes capable of promoting cellular responses (1-3). Members of the TRAF family share a common carboxy-terminal "TRAF domain", which mediates interactions with associated proteins; many also contain amino-terminal Zinc/RING finger motifs. The first TRAFs identified, TRAF1 and TRAF2, were found by virtue of their interactions with the cytoplasmic domain of TNF-receptor 2 (TNFRII) (4). The six known TRAFs (TRAF1-6) act as adaptor proteins for a wide range of cell surface receptors and participate in the regulation of cell survival, proliferation, differentiation, and stress responses.
TRAF5 regulates signaling through binding to the cytoplasmic domains of TNFR famly members including CD40, CD27, CD30, OX40, and lymphotoxin-β receptor (5-10). Overexpression of TRAF5 induces NF-κB activation. Research studies show that cytoplasmic aggregates of TRAF5, as well as TRAF2, are found in Hodgkin-Reed-Sternberg cells, resulting in constitutive NF-κB activation (11).
Studies of TRAF5 defecient mice suggest that it plays an important role in limiting Th2 immune responses that trigger T-cell mediated inflammatory diseases and asthma (12). Further studies indicate that TRAF5 binds to the IL-6 receptor gp130 and negatively controls Th17 differentation (13). In B-cells, TRAF5 negatively regulates toll-like receptor (TLR) mediated cytokine and antibody production (14).