TNIP1
Function
Inhibits NF-kappa-B activation and TNF-induced NF-kappa-B-dependent gene expression by regulating TAX1BP1 and A20/TNFAIP3-mediated deubiquitination of IKBKG; proposed to link A20/TNFAIP3 to ubiquitinated IKBKG (PubMed:21885437). Involved in regulation of EGF-induced ERK1/ERK2 signaling pathway; blocks MAPK3/MAPK1 nuclear translocation and MAPK1-dependent transcription. Increases cell surface CD4(T4) antigen expression. Involved in the anti-inflammatory response of macrophages and positively regulates TLR-induced activation of CEBPB. Involved in the prevention of autoimmunity; this function implicates binding to polyubiquitin. Involved in leukocyte integrin activation during inflammation; this function is mediated by association with SELPLG and dependent on phosphorylation by SRC-family kinases. Interacts with HIV-1 matrix protein and is packaged into virions and overexpression can inhibit viral replication. May regulate matrix nuclear localization, both nuclear import of PIC (Preintegration complex) and export of GAG polyprotein and viral genomic RNA during virion production. In case of infection, promotes association of IKBKG with Shigella flexneri E3 ubiquitin-protein ligase ipah9.8 p which in turn promotes polyubiquitination of IKBKG leading to its proteasome-dependent degradation and thus is perturbing NF-kappa-B activation during bacterial infection.
Post-translational modifications
Phosphorylation at Tyr-552 by SRC-family kinases recruits phosphoinositide-3-kinase (PI3K) PIK3CD:p85 heterodimer which results in integrin activation and leukocyte adhesion to activated endothelium during inflammation.
Tissue Specificity
Ubiquitous. Strongly expressed in peripheral blood lymphocytes, spleen and skeletal muscle, and is weakly expressed in the brain. In peripheral blood mononucleocytes, isoform 4 is mainly expressed and isoform 1 and isoform 7 are almost not expressed. Expression of isoform 1 and isoform 7 increases in leukemic cells.
Cellular localization
- Cytoplasm
- Nucleus
- Shuttles between the nucleus and cytoplasm in a CRM1-dependent manner.
Alternative names
KIAA0113, NAF1, TNIP1, TNFAIP3-interacting protein 1, A20-binding inhibitor of NF-kappa-B activation 1, HIV-1 Nef-interacting protein, Nef-associated factor 1, Nip40-1, Virion-associated nuclear shuttling protein, ABIN-1, Naf1, VAN, hVAN