Seroatlas · Human Serome Atlas

NIFK

MKI67 FHA domain-interacting nucleolar phosphoprotein

Also known as: hNIFK, MK67I_HUMAN, MKI67IP, Nopp34

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

Protein identityUniProt · HPA

UniProt accession
Q9BYG3
Gene
NIFK
Ensembl
ENSG00000155438
Chromosome
2
Canonical length
293 aa
Protein class
Predicted intracellular proteins
Subcellular location
Nucleoli,Nucleoli rim,Mitotic chromosome

OverviewNCBI Gene

This gene encodes a protein that interacts with the forkhead-associated domain of the Ki-67 antigen. The encoded protein may bind RNA and may play a role in mitosis and cell cycle progression. Multiple pseudogenes exist on chromosomes 5, 10, 12, 15, and 19.[provided by RefSeq, Jan 2009]

Canonical amino-acid sequenceUniProt

293 residues, UniProt reviewed canonical sequence.

>Q9BYG3|NIFK
     1  MATFSGPAGP ILSLNPQEDV EFQKEVAQVR KRITQRKKQE QLTPGVVYVR HLPNLLDETQ
    61  IFSYFSQFGT VTRFRLSRSK RTGNSKGYAF VEFESEDVAK IVAETMNNYL FGERLLECHF
   121  MPPEKVHKEL FKDWNIPFKQ PSYPSVKRYN RNRTLTQKLR MEERFKKKER LLRKKLAKKG
   181  IDYDFPSLIL QKTESISKTN RQTSTKGQVL RKKKKKVSGT LDTPEKTVDS QGPTPVCTPT
   241  FLERRKSQVA ELNDDDKDDE IVFKQPISCV KEEIQETQTP THSRKKRRRS SNQ

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against NIFK 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)
0.5
Highest tissue expression
44 nTPM

Expression across tissuesHPA

Tissue

  • lymph node: 44 nTPM
  • urinary bladder: 41 nTPM
  • tonsil: 40 nTPM
  • skeletal muscle: 38 nTPM
  • breast: 35 nTPM
  • ovary: 34 nTPM

Single-cell type

  • esophageal basal cells: 173 nCPM
  • esophageal suprabasal cells: 144 nCPM
  • differentiating spermatogonia: 134 nCPM
  • decidual stromal cells: 133 nCPM
  • fallopian secretory cells: 127 nCPM
  • oocytes: 124 nCPM

Immune cell

  • naive CD4 T-cell: 85 nTPM
  • MAIT T-cell: 84 nTPM
  • NK-cell: 82 nTPM
  • naive CD8 T-cell: 80 nTPM
  • naive B-cell: 75 nTPM
  • total PBMC: 75 nTPM

Brain region

  • cerebral cortex: 19 nTPM
  • white matter: 18 nTPM
  • hippocampal formation: 16 nTPM
  • spinal cord: 16 nTPM
  • cerebellum: 15 nTPM
  • hypothalamus: 15 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)
0.96
gnomAD pLI
0
gnomAD missense Z
-0.57
DepMap mean gene effect
-1.67
DepMap dependency class
pan

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 6% 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 NIFK 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 NIFK as an antibody target. Whether an autoantibody or antibody against NIFK could matter depends on whether native NIFK is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

NIFK 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 NIFK as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/NIFK. 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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