TNFAIP3 Antibody – Rabbit Polyclonal

This gene was identified as a gene whose expression is rapidly induced by the tumor necrosis factor (TNF). The protein encoded by this gene is a zinc finger protein and ubiqitin-editing enzyme, and has been shown to inhibit NF-kappa B activation as well as TNF-mediated apoptosis. The encoded protein, which has both ubiquitin ligase and deubiquitinase activities, is involved in the cytokine-mediated immune and inflammatory responses. Several transcript variants encoding the same protein have been found for this gene. [provided by RefSeq, Jul 2012]

Function: Ubiquitin-editing enzyme that contains both ubiquitin ligase and deubiquitinase activities. Involved in immune and inflammatory responses signaled by cytokines, such as TNF-alpha and IL-1 beta, or pathogens via Toll-like receptors (TLRs) through terminating NF-kappa-B activity. Essential component of a ubiquitin-editing protein complex, comprising also RNF11, ITCH and TAX1BP1, that ensures the transient nature of inflammatory signaling pathways. In cooperation with TAX1BP1 promotes disassembly of E2-E3 ubiquitin protein ligase complexes in IL-1R and TNFR-1 pathways; affected are at least E3 ligases TRAF6, TRAF2 and BIRC2, and E2 ubiquitin-conjugating enzymes UBE2N and UBE2D3. In cooperation with TAX1BP1 promotes ubiquitination of UBE2N and proteasomal degradation of UBE2N and UBE2D3. Upon TNF stimulation, deubiquitinates 'Lys-63'-polyubiquitin chains on RIPK1 and catalyzes the formation of 'Lys-48'-polyubiquitin chains. This leads to RIPK1 proteasomal degradation and consequently termination of the TNF- or LPS-mediated activation of NF-kappa-B. Deubiquinates TRAF6 probably acting on 'Lys-63'-linked polyubiquitin. Upon T-cell receptor (TCR)-mediated T-cell activation, deubiquitinates 'Lys-63'-polyubiquitin chains on MALT1 thereby mediating disassociation of the CBM (CARD11:BCL10:MALT1) and IKK complexes and preventing sustained IKK activation. Deubiquinates NEMO/IKBKG; the function is facilitated by TNIP1 and leads to inhibition of NF-kappa-B activation. Upon stimulation by bacterial peptidoglycans, probably deubiquitinates RIPK2. Can also inhibit I-kappa-B-kinase (IKK) through a non-catalytic mechanism which involves polyubiquitin; polyubiquitin promotes association with IKBKG and prevents IKK MAP3K7-mediated phosphorylation. Targets TRAF2 for lysosomal degradation. In vitro able to deubiquitinate 'Lys-11'-, 'Lys-48'- and 'Lys-63' polyubiquitin chains. Inhibitor of programmed cell death. Has a role in the function of the lymphoid system. Required for LPS-induced production of proinflammatory cytokines and IFN beta in LPS-tolerized macrophages. Ref.8 Ref.9 Ref.10 Ref.13 Ref.14 Ref.16 Ref.19 Ref.21 Ref.24 Ref.25 Ref.27 Ref.28

Catalytic activity: Thiol-dependent hydrolysis of ester, thioester, amide, peptide and isopeptide bonds formed by the C-terminal Gly of ubiquitin (a 76-residue protein attached to proteins as an intracellular targeting signal). Ref.25 Ref.27 Ref.28

Subunit structure: Homodimer. Interacts with TNIP1, TAX1BP1 and TRAF2. Interacts with RNF11, ITCH and TAX1BP1 only after TNF stimulation; these interaction are transient and they are lost after 1 hour of stimulation with TNF

By similarity. Interacts with YWHAZ and YWHAH. Interacts with IKBKG; the interaction is induced by TNF stimulation and by polyubiquitin. Interacts with RIPK1. Interacts with UBE2N; the interaction requires TAX1BP1. Interacts with TRAF6; the interaction is inhibited by HTLV-1 protein Tax. Ref.8 Ref.9 Ref.10 Ref.11 Ref.16 Ref.20 Ref.24

Subcellular location: Cytoplasm Ref.12 Ref.19 Ref.23. Nucleus. Lysosome Ref.12 Ref.19 Ref.23. A20p50: Cytoplasm Ref.12 Ref.19 Ref.23.

Induction: By TNF.

Domain: The A20-type zinc fingers mediate the ubiquitin ligase activity. The A20-type zinc finger 4 selectively recognizes 'Lys-63'-linked polyubiquitin. The A20-type zinc finger 4-7 are sufficient to bind polyubiquitin. Ref.14The OTU domain mediates the deubiquitinase activity. Ref.14

Post-translational modification: Proteolytically cleaved by MALT1 upon TCR stimulation; disrupts NF-kappa-B inhibitory function and results in increased IL-2 production. It is proposed that only a fraction of TNFAIP3 colocalized with TCR and CBM complex is cleaved, leaving the main TNFAIP3 pool intact. Ref.17 Ref.23

Sequence similarities: Belongs to the peptidase C64 family.Contains 7 A20-type zinc fingers.Contains 1 OTU domain.