TNF receptor-associated factor 3 (TRAF3)

TNF receptor-associated factor 3 (TRAF3) is a cytoplasmic adaptor protein belonging to the TRAF family that mediates signaling from members of the TNF receptor superfamily, including CD40, lymphotoxin-beta receptor, and BAFF-R, and participates in both positive and negative regulation of intracellular signaling pathways. TRAF3 is crucial in regulating NF-kappaB pathway activation, B and T cell survival, and the immune response. It interacts with a variety of immune receptors and viral proteins (e.g., Epstein-Barr virus LMP1), acting predominantly as a negative regulator in B cells and restraining immune cell activation and proliferation. Germline deletion or loss-of-function mutations in TRAF3 lead to immunodeficiency syndromes, increased risk of autoimmunity, and contribute to the development of B cell lymphomas. Its broad regulatory functions and association with multiple signaling pathways and immune pathologies make it a therapeutically relevant target. No approved drugs directly target TRAF3 as of this update, and it is not a direct target of marketed therapeutics; instead, it is being investigated for its role in immune-related diseases and cancer. TRAF3’s molecular mechanism largely centers on protein-protein interactions, not classic enzymatic activity or direct ligand binding. Its role as a signaling adaptor means it is key to both physiologic immune regulation and as a vulnerability in immune disorders and cancer.

Other names

CAP1LAP1CAP-1CRAF1IIAE5CD40bpRNF118CD40 binding protein 1CD40 associated protein 1