BioPAX pathway converted from "NF-kappa-B inhibitor binds NF-kappa-B complex" in the Reactome database. LEFT-TO-RIGHT NF-kappa-B inhibitor binds NF-kappa-B complex NF-kappa-B is sequestered in the cytosol of unstimulated cells through the interactions with a class of inhibitor proteins, called NF-kappa-B inhibitors (IkBs, NFKBIA or NFKBIB). IkBs proteins such as NFKBIA, NFKBIB or NFKBIE are characterized by the presence of six to seven ankyrin repeat motifs, which mediate interaction with the Rel homology domain (RHD). RHD mediates DNA binding, dimerization and nuclear localization (Jacobs MD & Harrison SC 1998; Manavalan B et al. 2010). NF-kappa-B inhibitors (IkBs) mask the nuclear localization signal (NLS) of the NF-kappa-B p65 subunit (ReLA, p65) preventing the nuclear translocation of NF-kappa-B (Jacobs MD & Harrison SC 1998; Cervantes CF et al. 2011). A key event in NF-kappa-B activation involves phosphorylation of IkB (at sites equivalent to Ser32 and Ser36 of NFKBIA (IkB-alpha) or Ser19 and Ser22 of NFKBIB (IkB-beta) by the IκB kinase (IKK) complex. The phosphorylated NFKBIA is recognized by the E3 ligase complex leading to K48-linked ubiquitination, and targeted for ubiquitin-mediated proteasomal degradation, releasing the NF-kappa-B dimer p50/p65 (RelA:NFKB1) into the nucleus to turn on target genes (Karin M & Ben-Neriah Y 2000, Kanarek N & Ben-Neriah Y 2012; Hoffmann A et al. 2006). Crystal structures of NF-kappa-B inhibitors:NF-kappaB complexes revealed that an NF-kappa-B dimer binds to one IkB molecule (Jacobs MD & Harrison SC 1998; Ghosh G et 2012). Authored: Shamovsky, Veronica, 2018-11-30 Reviewed: D'Eustachio, Peter, 2018-12-04 Reviewed: de Martin, R, 2022-05-04 Edited: Shamovsky, Veronica, 2018-12-05 NFkB Complex NFKB1(1-433), NFKB2(1-454):RELA Reactome DB_ID: 168155 cytosol GENE ONTOLOGY GO:0005829 Converted from EntitySet in Reactome NFkB NFKB1(1-433), NFKB2(1-454) Nuclear factor NF-kappa-B Reactome DB_ID: 177656 NFkB1 p50 NFKB1(1-433) Nuclear factor NF-kappa-B p105 subunit Reactome DB_ID: 168168 UniProt:P19838 NFKB1 NFKB1 FUNCTION NF-kappa-B is a pleiotropic transcription factor present in almost all cell types and is the endpoint of a series of signal transduction events that are initiated by a vast array of stimuli related to many biological processes such as inflammation, immunity, differentiation, cell growth, tumorigenesis and apoptosis. NF-kappa-B is a homo- or heterodimeric complex formed by the Rel-like domain-containing proteins RELA/p65, RELB, NFKB1/p105, NFKB1/p50, REL and NFKB2/p52 and the heterodimeric p65-p50 complex appears to be most abundant one. The dimers bind at kappa-B sites in the DNA of their target genes and the individual dimers have distinct preferences for different kappa-B sites that they can bind with distinguishable affinity and specificity. Different dimer combinations act as transcriptional activators or repressors, respectively. NF-kappa-B is controlled by various mechanisms of post-translational modification and subcellular compartmentalization as well as by interactions with other cofactors or corepressors. NF-kappa-B complexes are held in the cytoplasm in an inactive state complexed with members of the NF-kappa-B inhibitor (I-kappa-B) family. In a conventional activation pathway, I-kappa-B is phosphorylated by I-kappa-B kinases (IKKs) in response to different activators, subsequently degraded thus liberating the active NF-kappa-B complex which translocates to the nucleus. NF-kappa-B heterodimeric p65-p50 and RelB-p50 complexes are transcriptional activators. The NF-kappa-B p50-p50 homodimer is a transcriptional repressor, but can act as a transcriptional activator when associated with BCL3. NFKB1 appears to have dual functions such as cytoplasmic retention of attached NF-kappa-B proteins by p105 and generation of p50 by a cotranslational processing. The proteasome-mediated process ensures the production of both p50 and p105 and preserves their independent function, although processing of NFKB1/p105 also appears to occur post-translationally. p50 binds to the kappa-B consensus sequence 5'-GGRNNYYCC-3', located in the enhancer region of genes involved in immune response and acute phase reactions. In a complex with MAP3K8, NFKB1/p105 represses MAP3K8-induced MAPK signaling; active MAP3K8 is released by proteasome-dependent degradation of NFKB1/p105.SUBUNIT Component of the NF-kappa-B p65-p50 complex (PubMed:1740106). Homodimer; component of the NF-kappa-B p50-p50 complex. Component of the NF-kappa-B p105-p50 complex. Component of the NF-kappa-B p50-c-Rel complex (PubMed:15102766, PubMed:8152812). Component of a complex consisting of the NF-kappa-B p50-p50 homodimer and BCL3 (PubMed:10469655). Also interacts with MAP3K8 (PubMed:9950430, PubMed:15485931). NF-kappa-B p50 subunit interacts with NCOA3 coactivator, which may coactivate NF-kappa-B dependent expression via its histone acetyltransferase activity (PubMed:11094166). Interacts with DSIPI; this interaction prevents nuclear translocation and DNA-binding (PubMed:11468175, PubMed:12393603). Interacts with SPAG9 and UNC5CL (PubMed:14769797, PubMed:14743216). NFKB1/p105 interacts with CFLAR; the interaction inhibits p105 processing into p50 (PubMed:13679070). NFKB1/p105 forms a ternary complex with MAP3K8 and TNIP2 (PubMed:15169888). Interacts with GSK3B; the interaction prevents processing of p105 to p50 (PubMed:12871932). NFKB1/p50 interacts with NFKBIE (PubMed:9315679). NFKB1/p50 interacts with NFKBIZ (By similarity). Nuclear factor NF-kappa-B p50 subunit interacts with NFKBID (By similarity). Directly interacts with MEN1 (PubMed:11526476). Interacts with HIF1AN (PubMed:17003112). Interacts with FEM1A; interaction is direct (By similarity).INDUCTION By phorbol ester and TNF.DOMAIN The C-terminus of p105 might be involved in cytoplasmic retention, inhibition of DNA-binding, and transcription activation.DOMAIN Glycine-rich region (GRR) appears to be a critical element in the generation of p50.PTM While translation occurs, the particular unfolded structure after the GRR repeat promotes the generation of p50 making it an acceptable substrate for the proteasome. This process is known as cotranslational processing. The processed form is active and the unprocessed form acts as an inhibitor (I kappa B-like), being able to form cytosolic complexes with NF-kappa B, trapping it in the cytoplasm. Complete folding of the region downstream of the GRR repeat precludes processing.PTM Phosphorylation at 'Ser-903' and 'Ser-907' primes p105 for proteolytic processing in response to TNF-alpha stimulation. Phosphorylation at 'Ser-927' and 'Ser-932' are required for BTRC/BTRCP-mediated proteolysis.PTM Polyubiquitination seems to allow p105 processing.PTM S-nitrosylation of Cys-61 affects DNA binding.PTM The covalent modification of cysteine by 15-deoxy-Delta12,14-prostaglandin-J2 is autocatalytic and reversible. It may occur as an alternative to other cysteine modifications, such as S-nitrosylation and S-palmitoylation. Homo sapiens NCBI Taxonomy 9606 UniProt P19838 1 EQUAL 433 EQUAL Reactome Database ID Release 83 168168 Database identifier. Use this URL to connect to the web page of this instance in Reactome: http://www.reactome.org/cgi-bin/eventbrowser?DB=gk_current&ID=168168 Reactome R-HSA-168168 2 Reactome stable identifier. Use this URL to connect to the web page of this instance in Reactome: http://www.reactome.org/cgi-bin/eventbrowser_st_id?ST_ID=R-HSA-168168.2 Reactome http://www.reactome.org NFkB2 p52 NFKB2(1-454) Nuclear factor NF-kappa-B p52 subunit Reactome DB_ID: 168144 UniProt:Q00653 NFKB2 NFKB2 LYT10 FUNCTION NF-kappa-B is a pleiotropic transcription factor present in almost all cell types and is the endpoint of a series of signal transduction events that are initiated by a vast array of stimuli related to many biological processes such as inflammation, immunity, differentiation, cell growth, tumorigenesis and apoptosis. NF-kappa-B is a homo- or heterodimeric complex formed by the Rel-like domain-containing proteins RELA/p65, RELB, NFKB1/p105, NFKB1/p50, REL and NFKB2/p52. The dimers bind at kappa-B sites in the DNA of their target genes and the individual dimers have distinct preferences for different kappa-B sites that they can bind with distinguishable affinity and specificity. Different dimer combinations act as transcriptional activators or repressors, respectively. NF-kappa-B is controlled by various mechanisms of post-translational modification and subcellular compartmentalization as well as by interactions with other cofactors or corepressors. NF-kappa-B complexes are held in the cytoplasm in an inactive state complexed with members of the NF-kappa-B inhibitor (I-kappa-B) family. In a conventional activation pathway, I-kappa-B is phosphorylated by I-kappa-B kinases (IKKs) in response to different activators, subsequently degraded thus liberating the active NF-kappa-B complex which translocates to the nucleus. In a non-canonical activation pathway, the MAP3K14-activated CHUK/IKKA homodimer phosphorylates NFKB2/p100 associated with RelB, inducing its proteolytic processing to NFKB2/p52 and the formation of NF-kappa-B RelB-p52 complexes. The NF-kappa-B heterodimeric RelB-p52 complex is a transcriptional activator. The NF-kappa-B p52-p52 homodimer is a transcriptional repressor. NFKB2 appears to have dual functions such as cytoplasmic retention of attached NF-kappa-B proteins by p100 and generation of p52 by a cotranslational processing. The proteasome-mediated process ensures the production of both p52 and p100 and preserves their independent function. p52 binds to the kappa-B consensus sequence 5'-GGRNNYYCC-3', located in the enhancer region of genes involved in immune response and acute phase reactions. p52 and p100 are respectively the minor and major form; the processing of p100 being relatively poor. Isoform p49 is a subunit of the NF-kappa-B protein complex, which stimulates the HIV enhancer in synergy with p65. In concert with RELB, regulates the circadian clock by repressing the transcriptional activator activity of the CLOCK-ARNTL/BMAL1 heterodimer.SUBUNIT Component of the NF-kappa-B RelB-p52 complex. Homodimer; component of the NF-kappa-B p52-p52 complex. Component of the NF-kappa-B p65-p52 complex. Component of the NF-kappa-B p52-c-Rel complex. NFKB2/p52 interacts with NFKBIE. Component of a complex consisting of the NF-kappa-B p50-p50 homodimer and BCL3. Directly interacts with MEN1.DOMAIN The C-terminus of p100 might be involved in cytoplasmic retention, inhibition of DNA-binding by p52 homodimers, and/or transcription activation.DOMAIN The glycine-rich region (GRR) appears to be a critical element in the generation of p52.PTM While translation occurs, the particular unfolded structure after the GRR repeat promotes the generation of p52 making it an acceptable substrate for the proteasome. This process is known as cotranslational processing. The processed form is active and the unprocessed form acts as an inhibitor (I kappa B-like), being able to form cytosolic complexes with NF-kappa B, trapping it in the cytoplasm. Complete folding of the region downstream of the GRR repeat precludes processing.PTM Subsequent to MAP3K14-dependent serine phosphorylation, p100 polyubiquitination occurs then triggering its proteasome-dependent processing.PTM Constitutive processing is tightly suppressed by its C-terminal processing inhibitory domain, named PID, which contains the death domain.DISEASE A chromosomal aberration involving NFKB2 is found in a case of B-cell non Hodgkin lymphoma (B-NHL). Translocation t(10;14)(q24;q32) with IGHA1. The resulting oncogene is also called Lyt-10C alpha variant.DISEASE A chromosomal aberration involving NFKB2 is found in a cutaneous T-cell leukemia (C-TCL) cell line. This rearrangement produces the p80HT gene which codes for a truncated 80 kDa protein (p80HT).DISEASE In B-cell leukemia (B-CLL) cell line, LB40 and EB308, can be found after heterogeneous chromosomal aberrations, such as internal deletions. UniProt Q00653 1 EQUAL 454 EQUAL Reactome Database ID Release 83 168144 Database identifier. Use this URL to connect to the web page of this instance in Reactome: http://www.reactome.org/cgi-bin/eventbrowser?DB=gk_current&ID=168144 Reactome R-HSA-168144 1 Reactome stable identifier. Use this URL to connect to the web page of this instance in Reactome: http://www.reactome.org/cgi-bin/eventbrowser_st_id?ST_ID=R-HSA-168144.1 Reactome Database ID Release 83 177656 Database identifier. Use this URL to connect to the web page of this instance in Reactome: http://www.reactome.org/cgi-bin/eventbrowser?DB=gk_current&ID=177656 Reactome R-HSA-177656 3 Reactome stable identifier. Use this URL to connect to the web page of this instance in Reactome: http://www.reactome.org/cgi-bin/eventbrowser_st_id?ST_ID=R-HSA-177656.3 1 RELA Transcription factor p65 NFkB3 p65 Nuclear factor NF-kappa-B p65 subunit Reactome DB_ID: 168172 UniProt:Q04206 RELA RELA NFKB3 FUNCTION NF-kappa-B is a pleiotropic transcription factor present in almost all cell types and is the endpoint of a series of signal transduction events that are initiated by a vast array of stimuli related to many biological processes such as inflammation, immunity, differentiation, cell growth, tumorigenesis and apoptosis. NF-kappa-B is a homo- or heterodimeric complex formed by the Rel-like domain-containing proteins RELA/p65, RELB, NFKB1/p105, NFKB1/p50, REL and NFKB2/p52. The heterodimeric RELA-NFKB1 complex appears to be most abundant one. The dimers bind at kappa-B sites in the DNA of their target genes and the individual dimers have distinct preferences for different kappa-B sites that they can bind with distinguishable affinity and specificity. Different dimer combinations act as transcriptional activators or repressors, respectively. The NF-kappa-B heterodimeric RELA-NFKB1 and RELA-REL complexes, for instance, function as transcriptional activators. NF-kappa-B is controlled by various mechanisms of post-translational modification and subcellular compartmentalization as well as by interactions with other cofactors or corepressors. NF-kappa-B complexes are held in the cytoplasm in an inactive state complexed with members of the NF-kappa-B inhibitor (I-kappa-B) family. In a conventional activation pathway, I-kappa-B is phosphorylated by I-kappa-B kinases (IKKs) in response to different activators, subsequently degraded thus liberating the active NF-kappa-B complex which translocates to the nucleus. The inhibitory effect of I-kappa-B on NF-kappa-B through retention in the cytoplasm is exerted primarily through the interaction with RELA. RELA shows a weak DNA-binding site which could contribute directly to DNA binding in the NF-kappa-B complex. Beside its activity as a direct transcriptional activator, it is also able to modulate promoters accessibility to transcription factors and thereby indirectly regulate gene expression. Associates with chromatin at the NF-kappa-B promoter region via association with DDX1. Essential for cytokine gene expression in T-cells (PubMed:15790681). The NF-kappa-B homodimeric RELA-RELA complex appears to be involved in invasin-mediated activation of IL-8 expression. Key transcription factor regulating the IFN response during SARS-CoV-2 infection (PubMed:33440148).SUBUNIT Component of the NF-kappa-B p65-p50 complex. Component of the NF-kappa-B p65-c-Rel complex. Homodimer; component of the NF-kappa-B p65-p65 complex. Component of the NF-kappa-B p65-p52 complex. May interact with ETHE1. Binds TLE5 and TLE1. Interacts with TP53BP2. Binds to and is phosphorylated by the activated form of either RPS6KA4 or RPS6KA5. Interacts with ING4 and this interaction may be indirect. Interacts with CARM1, USP48 and UNC5CL. Interacts with IRAK1BP1 (By similarity). Interacts with NFKBID (By similarity). Interacts with NFKBIA (PubMed:1493333). Interacts with GSK3B. Interacts with NFKBIB (By similarity). Interacts with NFKBIE. Interacts with NFKBIZ. Interacts with EHMT1 (via ANK repeats) (PubMed:21515635). Part of a 70-90 kDa complex at least consisting of CHUK, IKBKB, NFKBIA, RELA, ELP1 and MAP3K14. Interacts with HDAC3; HDAC3 mediates the deacetylation of RELA. Interacts with HDAC1; the interaction requires non-phosphorylated RELA. Interacts with CBP; the interaction requires phosphorylated RELA. Interacts (phosphorylated at 'Thr-254') with PIN1; the interaction inhibits p65 binding to NFKBIA. Interacts with SOCS1. Interacts with UXT. Interacts with MTDH and PHF11. Interacts with ARRB2. Interacts with NFKBIA (when phosphorylated), the interaction is direct; phosphorylated NFKBIA is part of a SCF(BTRC)-like complex lacking CUL1. Interacts with RNF25. Interacts (via C-terminus) with DDX1. Interacts with UFL1 and COMMD1. Interacts with BRMS1; this promotes deacetylation of 'Lys-310'. Interacts with NOTCH2 (By similarity). Directly interacts with MEN1; this interaction represses NFKB-mediated transactivation. Interacts with AKIP1, which promotes the phosphorylation and nuclear retention of RELA. Interacts (via the RHD) with GFI1; the interaction, after bacterial lipopolysaccharide (LPS) stimulation, inhibits the transcriptional activity by interfering with the DNA-binding activity to target gene promoter DNA. Interacts (when acetylated at Lys-310) with BRD4; leading to activation of the NF-kappa-B pathway. Interacts with MEFV. Interacts with CLOCK (By similarity). Interacts (via N-terminus) with CPEN1; this interaction induces proteolytic cleavage of p65/RELA subunit and inhibition of NF-kappa-B transcriptional activity (PubMed:18212740). Interacts with FOXP3. Interacts with CDK5RAP3; stimulates the interaction of RELA with HDAC1, HDAC2 and HDAC3 thereby inhibiting NF-kappa-B transcriptional activity (PubMed:17785205). Interacts with DHX9; this interaction is direct and activates NF-kappa-B-mediated transcription (PubMed:15355351). Interacts with LRRC25 (PubMed:29044191). Interacts with TBX21 (By similarity). Interacts with KAT2A (By similarity). Interacts with ZBTB7A; involved in the control by RELA of the accessibility of target gene promoters (PubMed:29813070). Directly interacts with DDX3X; this interaction may trap RELA in the cytoplasm, impairing nuclear relocalization upon TNF activating signals (PubMed:27736973). Interacts with PHF2 (By similarity). Interacts with MKRN2; the interaction leads to its polyubiquitination and proteasome-dependent degradation (By similarity).SUBUNIT (Microbial infection) Interacts with human respiratory syncytial virus (HRSV) protein M2-1.SUBUNIT (Microbial infection) Interacts with molluscum contagiosum virus MC132.SUBUNIT (Microbial infection) Interacts with herpes virus 8 virus protein LANA1.SUBUNIT (Microbial infection) Interacts with human cytomegalovirus protein UL44; this interaction prevents NF-kappa-B binding to its promoters.DOMAIN The transcriptional activation domain 3/TA3 does not participate in the direct transcriptional activity of RELA but is involved in the control by RELA of the accessibility of target gene promoters. Mediates interaction with ZBTB7A.DOMAIN The transcriptional activation domain 1/TA1 and the transcriptional activation domain 2/TA2 have direct transcriptional activation properties (By similarity). The 9aaTAD motif found within the transcriptional activation domain 2 is a conserved motif present in a large number of transcription factors that is required for their transcriptional transactivation activity (PubMed:17467953).PTM Ubiquitinated by RNF182, leading to its proteasomal degradation. Degradation is required for termination of NF-kappa-B response.PTM Monomethylated at Lys-310 by SETD6 (PubMed:21515635). Monomethylation at Lys-310 is recognized by the ANK repeats of EHMT1 and promotes the formation of repressed chromatin at target genes, leading to down-regulation of NF-kappa-B transcription factor activity. Phosphorylation at Ser-311 disrupts the interaction with EHMT1 without preventing monomethylation at Lys-310 and relieves the repression of target genes (By similarity).PTM Phosphorylation at Ser-311 disrupts the interaction with EHMT1 and promotes transcription factor activity (By similarity). Phosphorylation on Ser-536 stimulates acetylation on Lys-310 and interaction with CBP; the phosphorylated and acetylated forms show enhanced transcriptional activity. Phosphorylation at Ser-276 by RPS6KA4 and RPS6KA5 promotes its transactivation and transcriptional activities.PTM Phosphorylation at Ser-75 by herpes simplex virus 1/HHV-1 inhibits NF-kappa-B activation.PTM Reversibly acetylated; the acetylation seems to be mediated by CBP, the deacetylation by HDAC3 and SIRT2. Acetylation at Lys-122 enhances DNA binding and impairs association with NFKBIA. Acetylation at Lys-310 is required for full transcriptional activity in the absence of effects on DNA binding and NFKBIA association. Acetylation at Lys-310 promotes interaction with BRD4. Acetylation can also lower DNA-binding and results in nuclear export. Interaction with BRMS1 promotes deacetylation of Lys-310. Lys-310 is deacetylated by SIRT2.PTM S-nitrosylation of Cys-38 inactivates the enzyme activity.PTM Sulfhydration at Cys-38 mediates the anti-apoptotic activity by promoting the interaction with RPS3 and activating the transcription factor activity.PTM Sumoylation by PIAS3 negatively regulates DNA-bound activated NF-kappa-B.PTM Proteolytically cleaved within a conserved N-terminus region required for base-specific contact with DNA in a CPEN1-mediated manner, and hence inhibits NF-kappa-B transcriptional activity (PubMed:18212740).DISEASE A chromosomal aberration involving ZFTA is found in more than two-thirds of supratentorial ependymomas. Translocation with ZFTA produces a ZFTA-RELA fusion protein. ZFTA-RELA translocations are potent oncogenes that probably transform neural stem cells by driving an aberrant NF-kappa-B transcription program (PubMed:24553141). UniProt Q04206 1 EQUAL 551 EQUAL Reactome Database ID Release 83 168172 Database identifier. Use this URL to connect to the web page of this instance in Reactome: http://www.reactome.org/cgi-bin/eventbrowser?DB=gk_current&ID=168172 Reactome R-HSA-168172 1 Reactome stable identifier. Use this URL to connect to the web page of this instance in Reactome: http://www.reactome.org/cgi-bin/eventbrowser_st_id?ST_ID=R-HSA-168172.1 1 Reactome Database ID Release 83 168155 Database identifier. Use this URL to connect to the web page of this instance in Reactome: http://www.reactome.org/cgi-bin/eventbrowser?DB=gk_current&ID=168155 Reactome R-HSA-168155 3 Reactome stable identifier. Use this URL to connect to the web page of this instance in Reactome: http://www.reactome.org/cgi-bin/eventbrowser_st_id?ST_ID=R-HSA-168155.3 Converted from EntitySet in Reactome IkB NFkB inhibitor NF-kappaB inhibitor IkBA, IkBB NFKBIA, NFKBIB Reactome DB_ID: 168143 IkBA NFKBIA NF-kappaB inhibitor alpha Reactome DB_ID: 168151 UniProt:P25963 NFKBIA NFKBIA IKBA MAD3 NFKBI FUNCTION Inhibits the activity of dimeric NF-kappa-B/REL complexes by trapping REL dimers in the cytoplasm through masking of their nuclear localization signals. On cellular stimulation by immune and pro-inflammatory responses, becomes phosphorylated promoting ubiquitination and degradation, enabling the dimeric RELA to translocate to the nucleus and activate transcription.SUBUNIT Interacts with RELA; the interaction requires the nuclear import signal. Interacts with NKIRAS1 and NKIRAS2. Part of a 70-90 kDa complex at least consisting of CHUK, IKBKB, NFKBIA, RELA, ELP1 and MAP3K14. Interacts with isoform 1 and isoform 2 of RWDD3; the interaction enhances sumoylation. Interacts (when phosphorylated at the 2 serine residues in the destruction motif D-S-G-X(2,3,4)-S) with BTRC. Associates with the SCF(BTRC) complex, composed of SKP1, CUL1 and BTRC; the association is mediated via interaction with BTRC. Part of a SCF(BTRC)-like complex lacking CUL1, which is associated with RELA; RELA interacts directly with NFKBIA. Interacts with PRMT2. Interacts with PRKACA in platelets; this interaction is disrupted by thrombin and collagen. Interacts with HIF1AN. Interacts with MEFV. Interacts with DDRGK1; positively regulates NFKBIA phosphorylation and degradation.SUBUNIT (Microbial infection) Interacts with HBV protein X.INDUCTION Induced in adherent monocytes.PTM Phosphorylated; disables inhibition of NF-kappa-B DNA-binding activity. Phosphorylation at positions 32 and 36 is prerequisite to recognition by UBE2D3 leading to polyubiquitination and subsequent degradation.PTM Sumoylated; sumoylation requires the presence of the nuclear import signal. Sumoylation blocks ubiquitination and proteasome-mediated degradation of the protein thereby increasing the protein stability.PTM Monoubiquitinated at Lys-21 and/or Lys-22 by UBE2D3. Ubiquitin chain elongation is then performed by CDC34 in cooperation with the SCF(FBXW11) E3 ligase complex, building ubiquitin chains from the UBE2D3-primed NFKBIA-linked ubiquitin. The resulting polyubiquitination leads to protein degradation. Also ubiquitinated by SCF(BTRC) following stimulus-dependent phosphorylation at Ser-32 and Ser-36.PTM Deubiquitinated by porcine reproductive and respiratory syndrome virus Nsp2 protein, which thereby interferes with NFKBIA degradation and impairs subsequent NF-kappa-B activation.SIMILARITY Belongs to the NF-kappa-B inhibitor family. UniProt P25963 1 EQUAL 317 EQUAL Reactome Database ID Release 83 168151 Database identifier. Use this URL to connect to the web page of this instance in Reactome: http://www.reactome.org/cgi-bin/eventbrowser?DB=gk_current&ID=168151 Reactome R-HSA-168151 2 Reactome stable identifier. Use this URL to connect to the web page of this instance in Reactome: http://www.reactome.org/cgi-bin/eventbrowser_st_id?ST_ID=R-HSA-168151.2 IkBB NFKBIB NF-kappaB inhibitor beta Reactome DB_ID: 168132 UniProt:Q15653 NFKBIB NFKBIB IKBB TRIP9 FUNCTION Inhibits NF-kappa-B by complexing with and trapping it in the cytoplasm. However, the unphosphorylated form resynthesized after cell stimulation is able to bind NF-kappa-B allowing its transport to the nucleus and protecting it to further NFKBIA-dependent inactivation. Association with inhibitor kappa B-interacting NKIRAS1 and NKIRAS2 prevent its phosphorylation rendering it more resistant to degradation, explaining its slower degradation.SUBUNIT Interacts with THRB (via ligand-binding domain) (PubMed:7776974). Interacts with RELA and REL (By similarity). Interacts with COMMD1 (PubMed:16573520). Interacts with inhibitor kappa B-interacting Ras-like NKIRAS1 and NKIRAS2 (PubMed:10657303, PubMed:12672800, PubMed:15024091).TISSUE SPECIFICITY Expressed in all tissues examined.PTM Phosphorylated by RPS6KA1; followed by degradation. Interaction with NKIRAS1 and NKIRAS2 probably prevents phosphorylation.SIMILARITY Belongs to the NF-kappa-B inhibitor family. UniProt Q15653 1 EQUAL 356 EQUAL Reactome Database ID Release 83 168132 Database identifier. Use this URL to connect to the web page of this instance in Reactome: http://www.reactome.org/cgi-bin/eventbrowser?DB=gk_current&ID=168132 Reactome R-HSA-168132 1 Reactome stable identifier. Use this URL to connect to the web page of this instance in Reactome: http://www.reactome.org/cgi-bin/eventbrowser_st_id?ST_ID=R-HSA-168132.1 Reactome Database ID Release 83 168143 Database identifier. Use this URL to connect to the web page of this instance in Reactome: http://www.reactome.org/cgi-bin/eventbrowser?DB=gk_current&ID=168143 Reactome R-HSA-168143 2 Reactome stable identifier. Use this URL to connect to the web page of this instance in Reactome: http://www.reactome.org/cgi-bin/eventbrowser_st_id?ST_ID=R-HSA-168143.2 IkBs:NFkB NFkB inhibitor:NFkB complex Reactome DB_ID: 168130 1 1 Reactome Database ID Release 83 168130 Database identifier. Use this URL to connect to the web page of this instance in Reactome: http://www.reactome.org/cgi-bin/eventbrowser?DB=gk_current&ID=168130 Reactome R-HSA-168130 2 Reactome stable identifier. Use this URL to connect to the web page of this instance in Reactome: http://www.reactome.org/cgi-bin/eventbrowser_st_id?ST_ID=R-HSA-168130.2 Reactome Database ID Release 83 9630923 Database identifier. Use this URL to connect to the web page of this instance in Reactome: http://www.reactome.org/cgi-bin/eventbrowser?DB=gk_current&ID=9630923 Reactome R-HSA-9630923 3 Reactome stable identifier. Use this URL to connect to the web page of this instance in Reactome: http://www.reactome.org/cgi-bin/eventbrowser_st_id?ST_ID=R-HSA-9630923.3 17072323 Pubmed 2006 Transcriptional regulation via the NF-kappaB signaling module Hoffmann, A Natoli, G Ghosh, G Oncogene 25:6706-16 22435546 Pubmed 2012 NF-κB regulation: lessons from structures Ghosh, Gourisankar Wang, Vivien Ya-Fan Huang, De-Bin Fusco, Amanda Immunol. Rev. 246:36-58 22435548 Pubmed 2012 Regulation of NF-κB by ubiquitination and degradation of the IκBs Kanarek, Naama Ben-Neriah, Yinon Immunol. Rev. 246:77-94 9865693 Pubmed 1998 Structure of an IkappaBalpha/NF-kappaB complex Jacobs, M D Harrison, S C Cell 95:749-58 21203422 Pubmed 2010 Structure-function relationship of cytoplasmic and nuclear IκB proteins: an in silico analysis Manavalan, Balachandran Basith, Shaherin Choi, Yong-Min Lee, Gwang Choi, Sangdun PLoS ONE 5:e15782 15145317 Pubmed 2004 The two NF-kappaB activation pathways and their role in innate and adaptive immunity Bonizzi, G Karin, M Trends Immunol 25:280-8 21094161 Pubmed 2011 The RelA nuclear localization signal folds upon binding to IκBα Cervantes, Carla F Bergqvist, Simon Kjaergaard, Magnus Kroon, Gerard Sue, Shih-Che Dyson, H Jane Komives, Elizabeth A J. Mol. Biol. 405:754-64 10837071 Pubmed 2000 Phosphorylation meets ubiquitination: the control of NF-[kappa]B activity Karin, M Ben-Neriah, Y Annu. Rev. Immunol. 18:621-63