Seroatlas · Human Serome Atlas

NFKBIB

NF-kappa-B inhibitor beta

Also known as: IKBB, IKBB_HUMAN, TRIP9

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession
Q15653
Gene
NFKBIB
Ensembl
ENSG00000104825
Chromosome
19
Canonical length
356 aa
Protein class
Predicted intracellular proteins, Transcription factors
Subcellular location
Nucleoplasm,Cytosol

OverviewNCBI Gene

The protein encoded by this gene belongs to the NF-kappa-B inhibitor family, which inhibit NF-kappa-B by complexing with, and trapping it in the cytoplasm. Phosphorylation of serine residues on these proteins by kinases marks them for destruction via the ubiquitination pathway, thereby allowing activation of the NF-kappa-B, which translocates to the nucleus to function as a transcription factor. Alternatively spliced transcript variants have been found for this gene.[provided by RefSeq, Jul 2011]

Canonical amino-acid sequenceUniProt

356 residues, UniProt reviewed canonical sequence.

>Q15653|NFKBIB
     1  MAGVACLGKA ADADEWCDSG LGSLGPDAAA PGGPGLGAEL GPGLSWAPLV FGYVTEDGDT
    61  ALHLAVIHQH EPFLDFLLGF SAGTEYMDLQ NDLGQTALHL AAILGETSTV EKLYAAGAGL
   121  CVAERRGHTA LHLACRVGAH ACARALLQPR PRRPREAPDT YLAQGPDRTP DTNHTPVALY
   181  PDSDLEKEEE ESEEDWKLQL EAENYEGHTP LHVAVIHKDV EMVRLLRDAG ADLDKPEPTC
   241  GRSPLHLAVE AQAADVLELL LRAGANPAAR MYGGRTPLGS AMLRPNPILA RLLRAHGAPE
   301  PEGEDEKSGP CSSSSDSDSG DEGDEYDDIV VHSSRSQTRL PPTPASKPLP DDPRPV

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against NFKBIB can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability
Intracellular
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.39
Highest tissue expression
72 nTPM

Expression across tissuesHPA

Tissue

  • testis: 72 nTPM
  • skeletal muscle: 28 nTPM
  • liver: 20 nTPM
  • spinal cord: 16 nTPM
  • blood vessel: 16 nTPM
  • heart muscle: 15 nTPM

Single-cell type

  • late spermatids: 1,279 nCPM
  • early spermatids: 896 nCPM
  • late primary spermatocytes: 37 nCPM
  • syncytiotrophoblasts: 35 nCPM
  • enterocytes: 18 nCPM
  • epididymal basal cells: 16 nCPM

Immune cell

  • eosinophil: 10 nTPM
  • neutrophil: 7.5 nTPM
  • NK-cell: 7.1 nTPM
  • T-reg: 5.9 nTPM
  • intermediate monocyte: 4.9 nTPM
  • plasmacytoid DC: 4.3 nTPM

Brain region

  • white matter: 11 nTPM
  • basal ganglia: 11 nTPM
  • thalamus: 10 nTPM
  • medulla oblongata: 9.8 nTPM
  • cerebral cortex: 9.5 nTPM
  • midbrain: 9.5 nTPM

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)
0.56
gnomAD pLI
0.42
gnomAD missense Z
0.97
DepMap mean gene effect
-0.13
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 9% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of NFKBIB in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads NFKBIB as an antibody target. Whether an autoantibody or antibody against NFKBIB could matter depends on whether native NFKBIB is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

NFKBIB is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label NFKBIB as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/NFKBIB. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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