NFKBIB

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Description

The NFKBIB (NFKB inhibitor beta) is a protein-coding gene located on chromosome 19.

NF-kappa-B inhibitor beta (NFKBIB) is a protein encoded by the NFKBIB gene in humans. It forms a complex with NFKB1 or NFKB2, which are bound to REL, RELA, or RELB, to form the NFKB complex. NFKBIB inhibits the NFKB complex by trapping it in the cytoplasm. Phosphorylation of NFKBIB by kinases (IKBKA or IKBKB) marks it for destruction via the ubiquitination pathway, activating the NFKB complex. Activated NFKB translocates to the nucleus and binds DNA at kappa-B-binding motifs. NFKBIB interacts with IKK2, RELA, and Retinoid X receptor alpha.

NFKBIB inhibits NF-kappa-B by binding to and retaining it in the cytoplasm. However, upon cell activation, a newly synthesized unphosphorylated form of NFKBIB can bind to NF-kappa-B, enabling its translocation to the nucleus and shielding it from further inactivation by NFKBIA. The interaction of NFKBIB with NKIRAS1 and NKIRAS2 prevents phosphorylation, making it more resistant to degradation and explaining its slower degradation rate.

NFKBIB is also known as IKBB, TRIP9.

Associated Diseases

• gastrointestinal stromal tumor
• common variable immunodeficiency
• isolated agammaglobulinemia
• immunodeficiency 18
• combined immunodeficiency with skin granulomas
• immunodeficiency 99 with hypogammaglobulinemia and autoimmune cytopenias
• immunodeficiency 62
• hyper-IgE recurrent infection syndrome 5, autosomal recessive
• immunodeficiency 73c with defective neutrophil chemotaxis and hypogammaglobulinemia
• immunodeficiency, common variable, 4
• BENTA disease
• severe combined immunodeficiency due to DCLRE1C deficiency
• immunodeficiency 67
• Cernunnos-XLF deficiency
• neutropenia, severe congenital, 1, autosomal dominant
• severe combined immunodeficiency due to CTPS1 deficiency
• severe combined immunodeficiency due to LAT deficiency
• pancytopenia due to IKZF1 mutations
• immunodeficiency 73b with defective neutrophil chemotaxis and lymphopenia