Seroatlas · Human Serome Atlas

KPNA3

Importin subunit alpha-4

Also known as: hSRP1, IMA4_HUMAN, IPOA4, SRP1gamma, SRP4

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

Protein identityUniProt · HPA

UniProt accession
O00505
Gene
KPNA3
Ensembl
ENSG00000102753
Chromosome
13
Canonical length
521 aa
Protein class
Human disease related genes, Predicted intracellular proteins, Transporters
Subcellular location
Nucleoplasm,Cytosol

OverviewNCBI Gene

The transport of molecules between the nucleus and the cytoplasm in eukaryotic cells is mediated by the nuclear pore complex (NPC), which consists of 60-100 proteins. Small molecules (up to 70 kD) can pass through the nuclear pore by nonselective diffusion while larger molecules are transported by an active process. The protein encoded by this gene belongs to the importin alpha family, and is involved in nuclear protein import. [provided by RefSeq, Jan 2009]

Canonical amino-acid sequenceUniProt

521 residues, UniProt reviewed canonical sequence.

>O00505|KPNA3
     1  MAENPSLENH RIKSFKNKGR DVETMRRHRN EVTVELRKNK RDEHLLKKRN VPQEESLEDS
    61  DVDADFKAQN VTLEAILQNA TSDNPVVQLS AVQAARKLLS SDRNPPIDDL IKSGILPILV
   121  KCLERDDNPS LQFEAAWALT NIASGTSAQT QAVVQSNAVP LFLRLLRSPH QNVCEQAVWA
   181  LGNIIGDGPQ CRDYVISLGV VKPLLSFISP SIPITFLRNV TWVIVNLCRN KDPPPPMETV
   241  QEILPALCVL IYHTDINILV DTVWALSYLT DGGNEQIQMV IDSGVVPFLV PLLSHQEVKV
   301  QTAALRAVGN IVTGTDEQTQ VVLNCDVLSH FPNLLSHPKE KINKEAVWFL SNITAGNQQQ
   361  VQAVIDAGLI PMIIHQLAKG DFGTQKEAAW AISNLTISGR KDQVEYLVQQ NVIPPFCNLL
   421  SVKDSQVVQV VLDGLKNILI MAGDEASTIA EIIEECGGLE KIEVLQQHEN EDIYKLAFEI
   481  IDQYFSGDDI DEDPCLIPEA TQGGTYNFDP TANLQTKEFN F

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against KPNA3 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
136 nTPM

Expression across tissuesHPA

Tissue

  • skeletal muscle: 136 nTPM
  • tongue: 88 nTPM
  • retina: 31 nTPM
  • heart muscle: 30 nTPM
  • bone marrow: 28 nTPM
  • testis: 27 nTPM

Single-cell type

  • early spermatids: 429 nCPM
  • rod photoreceptor cells: 382 nCPM
  • myonuclei: 279 nCPM
  • late spermatids: 263 nCPM
  • cone photoreceptor cells: 230 nCPM
  • sertoli cells: 224 nCPM

Immune cell

  • basophil: 10 nTPM
  • MAIT T-cell: 9.3 nTPM
  • T-reg: 8.5 nTPM
  • gdT-cell: 6.7 nTPM
  • memory CD4 T-cell: 6.7 nTPM
  • NK-cell: 6.7 nTPM

Brain region

  • white matter: 34 nTPM
  • spinal cord: 31 nTPM
  • hippocampal formation: 30 nTPM
  • hypothalamus: 30 nTPM
  • cerebral cortex: 29 nTPM
  • basal ganglia: 28 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about KPNA3.

Disease | AllUniProt

Conditions KPNA3 is implicated in, by any mechanism.

  • Spastic paraplegia 88, autosomal dominant (SPG88) MIM:620106

Disease | GeneticClinVar

6 pathogenic / likely-pathogenic of 73 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Spastic paraplegia 88, autosomal dominant

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)
0.33
gnomAD pLI
0.95
gnomAD missense Z
3.39
DepMap mean gene effect
0.04
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 5% 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 KPNA3 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 KPNA3 as an antibody target. Whether an autoantibody or antibody against KPNA3 could matter depends on whether native KPNA3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

KPNA3 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 KPNA3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/KPNA3. 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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