Seroatlas · Human Serome Atlas

CATSPER2

Cation channel sperm-associated protein 2

Also known as: CTSR2_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q96P56
Gene
CATSPER2
Ensembl
ENSG00000166762
Chromosome
15
Canonical length
530 aa
Protein class
Disease related genes, Human disease related genes, Plasma proteins, Potential drug targets, Predicted intracellular proteins, Predicted membrane proteins, Transporters, Voltage-gated ion channels
Subcellular location
Vesicles,Plasma membrane,Primary cilium,Principal piece,End piece

OverviewNCBI Gene

This gene encodes a member of a family of cation channel proteins that localize to the flagellum of spermatozoa. Defects at this locus causes male infertility. Alternatively spliced transcript variants have been observed at this locus. Readthrough transcription originates upstream of this locus in diphosphoinositol pentakisphosphate kinase 1 pseudogene 1 and is represented by GeneID:110006325. Related pseudogenes are found next to this locus on chromosome 15 and on chromosome 5. [provided by RefSeq, Mar 2017]

Canonical amino-acid sequenceUniProt

530 residues, UniProt reviewed canonical sequence.

>Q96P56|CATSPER2
     1  MAAYQQEEQM QLPRADAIRS RLIDTFSLIE HLQGLSQAVP RHTIRELLDP SRQKKLVLGD
    61  QHQLVRFSIK PQRIEQISHA QRLLSRLHVR CSQRPPLSLW AGWVLECPLF KNFIIFLVFL
   121  NTIILMVEIE LLESTNTKLW PLKLTLEVAA WFILLIFILE ILLKWLSNFS VFWKSAWNVF
   181  DFVVTMLSLL PEVVVLVGVT GQSVWLQLLR ICRVLRSLKL LAQFRQIQII ILVLVRALKS
   241  MTFLLMLLLI FFYIFAVTGV YVFSEYTRSP RQDLEYHVFF SDLPNSLVTV FILFTLDHWY
   301  ALLQDVWKVP EVSRIFSSIY FILWLLLGSI IFRSIIVAMM VTNFQNIRKE LNEEMARREV
   361  QLKADMFKRQ IIQRRKNMSH EALTSSHSKI EDSSRGASQQ RESLDLSEVS EVESNYGATE
   421  EDLITSASKT EETLSKKREY QSSSCVSSTS SSYSSSSESR FSESIGRLDW ETLVHENLPG
   481  LMEMDQDDRV WPRDSLFRYF ELLEKLQYNL EERKKLQEFA VQALMNLEDK

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CATSPER2 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)
0.45
Highest tissue expression
21 nTPM

Expression across tissuesHPA

Tissue

  • retina: 21 nTPM
  • testis: 15 nTPM
  • cerebellum: 8.1 nTPM
  • skin: 6.7 nTPM
  • epididymis: 6.3 nTPM
  • bone marrow: 5.5 nTPM

Single-cell type

  • rod photoreceptor cells: 306 nCPM
  • cone photoreceptor cells: 197 nCPM
  • brain excitatory neurons: 154 nCPM
  • sertoli cells: 144 nCPM
  • corticotrophs: 143 nCPM
  • lactotrophs: 126 nCPM

Immune cell

  • memory B-cell: 1.1 nTPM
  • naive CD8 T-cell: 0.6 nTPM
  • memory CD8 T-cell: 0.5 nTPM
  • neutrophil: 0.5 nTPM
  • MAIT T-cell: 0.4 nTPM
  • naive CD4 T-cell: 0.4 nTPM

Brain region

  • cerebellum: 44 nTPM
  • white matter: 22 nTPM
  • cerebral cortex: 22 nTPM
  • amygdala: 18 nTPM
  • hippocampal formation: 18 nTPM
  • pons: 17 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about CATSPER2.

Disease | AllUniProt

Conditions CATSPER2 is implicated in, by any mechanism.

Disease | GeneticClinVar

2 pathogenic / likely-pathogenic of 139 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

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)
1.22
gnomAD pLI
0
gnomAD missense Z
-0.75
DepMap mean gene effect
0.01
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% 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 CATSPER2 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 CATSPER2 as an antibody target. Whether an autoantibody or antibody against CATSPER2 could matter depends on whether native CATSPER2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CATSPER2 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 CATSPER2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CATSPER2. 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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