Seroatlas · Human Serome Atlas

SPINK2

Serine protease inhibitor Kazal-type 2

Also known as: HUSI-II, ISK2_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P20155
Gene
SPINK2
Ensembl
ENSG00000128040
Chromosome
4
Canonical length
84 aa
Protein class
Disease related genes, Human disease related genes, Predicted secreted proteins
Subcellular location
Acrosome,Equatorial segment
Secretome location
Secreted to blood

OverviewNCBI Gene

This gene encodes a member of the family of serine protease inhibitors of the Kazal type (SPINK). The encoded protein acts as a trypsin and acrosin inhibitor in the genital tract and is localized in the spermatozoa. The protein has been associated with the progression of lymphomas. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Nov 2012]

Canonical amino-acid sequenceUniProt

84 residues, UniProt reviewed canonical sequence.

>P20155|SPINK2
     1  MALSVLRLAL LLLAVTFAAS LIPQFGLFSK YRTPNCSQYR LPGCPRHFNP VCGSDMSTYA
    61  NECTLCMKIR EGGHNIKIIR NGPC

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SPINK2 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
Secreted
Secreted
Yes
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.43
Highest tissue expression
4,956 nTPM

Expression across tissuesHPA

Tissue

  • epididymis: 4,956 nTPM
  • testis: 330 nTPM
  • seminal vesicle: 222 nTPM
  • bone marrow: 13 nTPM
  • choroid plexus: 9 nTPM
  • heart muscle: 7.2 nTPM

Single-cell type

  • epididymal principal cells: 27,209 nCPM
  • late primary spermatocytes: 4,199 nCPM
  • late spermatids: 2,160 nCPM
  • early spermatids: 943 nCPM
  • epididymal basal cells: 933 nCPM
  • early primary spermatocytes: 657 nCPM

Immune cell

  • NK-cell: 144 nTPM
  • naive CD8 T-cell: 21 nTPM
  • naive CD4 T-cell: 11 nTPM
  • naive B-cell: 11 nTPM
  • memory B-cell: 8.5 nTPM
  • memory CD8 T-cell: 5.3 nTPM

Brain region

  • choroid plexus: 3.7 nTPM
  • midbrain: 0.7 nTPM
  • thalamus: 0.6 nTPM
  • cerebral cortex: 0.5 nTPM
  • medulla oblongata: 0.5 nTPM
  • pons: 0.5 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about SPINK2.

Disease | AllUniProt

Conditions SPINK2 is implicated in, by any mechanism.

Disease | GeneticClinVar

1 pathogenic / likely-pathogenic of 23 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Spermatogenic failure 29

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)
1.49
gnomAD pLI
0.07
gnomAD missense Z
0.66
DepMap mean gene effect
-0.02
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 2% 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

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads SPINK2 as an antibody target. Whether an autoantibody or antibody against SPINK2 could matter depends on whether native SPINK2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SPINK2 is annotated as secreted, so native SPINK2 circulates and is directly accessible to antibodies. Secreted and cell-surface proteins are the autoantibody targets most likely to act like drugs, blocking or depleting the native protein.

Annotation status

The present source text does not explicitly label SPINK2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/SPINK2. 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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