Seroatlas · Human Serome Atlas

KPNA4

Importin subunit alpha-3

Also known as: IMA3_HUMAN, IPOA3, MGC12217, MGC26703, QIP1, SRP3

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

Protein identityUniProt · HPA

UniProt accession
O00629
Gene
KPNA4
Ensembl
ENSG00000186432
Chromosome
3
Canonical length
521 aa
Protein class
Predicted intracellular proteins, Transporters
Subcellular location
Nucleoplasm,Nuclear membrane

OverviewNCBI Gene

The nuclear import of karyophilic proteins is directed by short amino acid sequences termed nuclear localization signals (NLSs). Karyopherins, or importins, are cytoplasmic proteins that recognize NLSs and dock NLS-containing proteins to the nuclear pore complex. The protein encoded by this gene shares the sequence similarity with Xenopus importin-alpha and Saccharomyces cerevisiae Srp1. This protein is found to interact with the NLSs of DNA helicase Q1 and SV40 T antigen. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

521 residues, UniProt reviewed canonical sequence.

>O00629|KPNA4
     1  MADNEKLDNQ RLKNFKNKGR DLETMRRQRN EVVVELRKNK RDEHLLKRRN VPHEDICEDS
    61  DIDGDYRVQN TSLEAIVQNA SSDNQGIQLS AVQAARKLLS SDRNPPIDDL IKSGILPILV
   121  HCLERDDNPS LQFEAAWALT NIASGTSEQT QAVVQSNAVP LFLRLLHSPH QNVCEQAVWA
   181  LGNIIGDGPQ CRDYVISLGV VKPLLSFISP SIPITFLRNV TWVMVNLCRH KDPPPPMETI
   241  QEILPALCVL IHHTDVNILV DTVWALSYLT DAGNEQIQMV IDSGIVPHLV PLLSHQEVKV
   301  QTAALRAVGN IVTGTDEQTQ VVLNCDALSH FPALLTHPKE KINKEAVWFL SNITAGNQQQ
   361  VQAVIDANLV PMIIHLLDKG DFGTQKEAAW AISNLTISGR KDQVAYLIQQ NVIPPFCNLL
   421  TVKDAQVVQV VLDGLSNILK MAEDEAETIG NLIEECGGLE KIEQLQNHEN EDIYKLAYEI
   481  IDQFFSSDDI DEDPSLVPEA IQGGTFGFNS SANVPTEGFQ F

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against KPNA4 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)
0.28
Highest tissue expression
117 nTPM

Expression across tissuesHPA

Tissue

  • skeletal muscle: 117 nTPM
  • tongue: 56 nTPM
  • heart muscle: 21 nTPM
  • adipose tissue: 19 nTPM
  • esophagus: 16 nTPM
  • bone marrow: 14 nTPM

Single-cell type

  • neutrophils: 433 nCPM
  • neutrophil progenitors: 285 nCPM
  • urothelial cells: 263 nCPM
  • endometrial secretory cells: 250 nCPM
  • salivary basal cells: 240 nCPM
  • salivary myoepithelial cells: 216 nCPM

Immune cell

  • basophil: 7.6 nTPM
  • non-classical monocyte: 5.7 nTPM
  • neutrophil: 4.2 nTPM
  • NK-cell: 4 nTPM
  • intermediate monocyte: 3.5 nTPM
  • eosinophil: 2.9 nTPM

Brain region

  • hypothalamus: 36 nTPM
  • cerebellum: 35 nTPM
  • white matter: 35 nTPM
  • medulla oblongata: 34 nTPM
  • pons: 33 nTPM
  • spinal cord: 33 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)
0.16
gnomAD pLI
1
gnomAD missense Z
3.23
DepMap mean gene effect
-0.26
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 15% 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 KPNA4 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 KPNA4 as an antibody target. Whether an autoantibody or antibody against KPNA4 could matter depends on whether native KPNA4 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

KPNA4 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 KPNA4 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/KPNA4. 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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