Seroatlas · Human Serome Atlas

CATSPER3

Cation channel sperm-associated protein 3

Also known as: CACRC, CTSR3_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q86XQ3
Gene
CATSPER3
Ensembl
ENSG00000152705
Chromosome
5
Canonical length
398 aa
Protein class
Predicted membrane proteins, Transporters
Subcellular location
Mid piece,Principal piece

OverviewNCBI Gene

Predicted to enable voltage-gated calcium channel activity. Predicted to be involved in flagellated sperm motility; sodium ion transport; and sperm capacitation. Predicted to act upstream of or within establishment of localization in cell. Predicted to be located in plasma membrane. Predicted to be part of CatSper complex. Predicted to be active in acrosomal vesicle. [provided by Alliance of Genome Resources, Jul 2025]

Canonical amino-acid sequenceUniProt

398 residues, UniProt reviewed canonical sequence.

>Q86XQ3|CATSPER3
     1  MSQHRHQRHS RVISSSPVDT TSVGFCPTFK KFKRNDDECR AFVKRVIMSR FFKIIMISTV
    61  TSNAFFMALW TSYDIRYRLF RLLEFSEIFF VSICTSELSM KVYVDPINYW KNGYNLLDVI
   121  IIIVMFLPYA LRQLMGKQFT YLYIADGMQS LRILKLIGYS QGIRTLITAV GQTVYTVASV
   181  LLLLFLLMYI FAILGFCLFG SPDNGDHDNW GNLAAAFFTL FSLATVDGWT DLQKQLDNRE
   241  FALSRAFTII FILLASFIFL NMFVGVMIMH TEDSIRKFER ELMLEQQEML MGEKQVILQR
   301  QQEEISRLMH IQKNADCTSF SELVENFKKT LSHTDPMVLD DFGTSLPFID IYFSTLDYQD
   361  TTVHKLQELY YEIVHVLSLM LEDLPQEKPQ SLEKVDEK

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CATSPER3 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
6
Mean surface accessibility (rSASA)
0.42
Highest tissue expression
28 nTPM

Expression across tissuesHPA

Tissue

  • testis: 28 nTPM
  • skeletal muscle: 2.8 nTPM
  • retina: 2.5 nTPM
  • liver: 1.8 nTPM
  • tongue: 1.7 nTPM
  • kidney: 1.6 nTPM

Single-cell type

  • early spermatids: 202 nCPM
  • late primary spermatocytes: 145 nCPM
  • late spermatids: 80 nCPM
  • paneth cells: 3.9 nCPM
  • cholangiocytes: 2 nCPM
  • sertoli cells: 1.4 nCPM

Immune cell

  • naive B-cell: 1.7 nTPM
  • NK-cell: 1.2 nTPM
  • naive CD4 T-cell: 0.5 nTPM
  • myeloid DC: 0.4 nTPM
  • memory B-cell: 0.2 nTPM
  • memory CD4 T-cell: 0.2 nTPM

Brain region

  • choroid plexus: 3.1 nTPM
  • medulla oblongata: 1.6 nTPM
  • hypothalamus: 1.4 nTPM
  • midbrain: 1.4 nTPM
  • basal ganglia: 1.3 nTPM
  • pons: 1.3 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about CATSPER3.

Disease | ImmuneIEDB

Conditions an epitope on CATSPER3 was assayed in.

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)
0.98
gnomAD pLI
0
gnomAD missense Z
-0.33
DepMap mean gene effect
-0.14
DepMap dependency class
selective

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 CATSPER3 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 CATSPER3 as an antibody target. Whether an autoantibody or antibody against CATSPER3 could matter depends on whether native CATSPER3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CATSPER3 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 CATSPER3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CATSPER3. 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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