Seroatlas · Human Serome Atlas

CABYR

Calcium-binding tyrosine phosphorylation-regulated protein

Also known as: CABYR_HUMAN, CBP86, CT88, FSP-2

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

Protein identityUniProt · HPA

UniProt accession
O75952
Gene
CABYR
Ensembl
ENSG00000154040
Chromosome
18
Canonical length
493 aa
Protein class
Predicted intracellular proteins
Subcellular location
Nucleoplasm,Cytosol,Principal piece

OverviewNCBI Gene

To reach fertilization competence, spermatozoa undergo a series of morphological and molecular maturational processes, termed capacitation, involving protein tyrosine phosphorylation and increased intracellular calcium. The protein encoded by this gene localizes to the principal piece of the sperm flagellum in association with the fibrous sheath and exhibits calcium-binding when phosphorylated during capacitation. A pseudogene on chromosome 3 has been identified for this gene. Alternatively spliced transcript variants encoding distinct protein isoforms have been found for this gene. [provided by RefSeq, Jul 2013]

Canonical amino-acid sequenceUniProt

493 residues, UniProt reviewed canonical sequence.

>O75952|CABYR
     1  MISSKPRLVV PYGLKTLLEG ISRAVLKTNP SNINQFAAAY FQELTMYRGN TTMDIKDLVK
    61  QFHQIKVEKW SEGTTPQKKL ECLKEPGKTS VESKVPTQME KSTDTDEDNV TRTEYSDKTT
   121  QFPSVYAVPG TEQTEAVGGL SSKPATPKTT TPPSSPPPTA VSPEFAYVPA DPAQLAAQML
   181  GKVSSIHSDQ SDVLMVDVAT SMPVVIKEVP SSEAAEDVMV AAPLVCSGKV LEVQVVNQTS
   241  VHVDLGSQPK ENEAEPSTAS SVPLQDEQEP PAYDQAPEVT LQADIEVMST VHISSVYNDV
   301  PVTEGVVYIE QLPEQIVIPF TDQVACLKEN EQSKENEQSP RVSPKSVVEK TTSGMSKKSV
   361  ESVKLAQLEE NAKYSSVYME AEATALLSDT SLKGQPEVPA QLLDAEGAIK IGSEKSLHLE
   421  VEITSIVSDN TGQEESGENS VPQEMEGKPV LSGEAAEAVH SGTSVKSSSG PFPPAPEGLT
   481  APEIEPEGES TAE

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CABYR 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)
0.65
Highest tissue expression
288 nTPM

Expression across tissuesHPA

Tissue

  • testis: 288 nTPM
  • choroid plexus: 12 nTPM
  • pituitary gland: 8 nTPM
  • cerebral cortex: 7.5 nTPM
  • hippocampal formation: 6.6 nTPM
  • spinal cord: 6.6 nTPM

Single-cell type

  • late spermatids: 5,981 nCPM
  • early spermatids: 2,841 nCPM
  • late primary spermatocytes: 1,096 nCPM
  • epicardial cells: 221 nCPM
  • oocytes: 207 nCPM
  • endometrial ciliated cells: 122 nCPM

Immune cell

  • basophil: 5.6 nTPM
  • naive B-cell: 5.4 nTPM
  • memory B-cell: 4.8 nTPM
  • neutrophil: 2 nTPM
  • NK-cell: 0.9 nTPM
  • naive CD8 T-cell: 0.7 nTPM

Brain region

  • choroid plexus: 32 nTPM
  • white matter: 30 nTPM
  • cerebral cortex: 29 nTPM
  • hypothalamus: 26 nTPM
  • hippocampal formation: 25 nTPM
  • pons: 24 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)
1.13
gnomAD pLI
0
gnomAD missense Z
0.41
DepMap mean gene effect
0.02
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 CABYR 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 CABYR as an antibody target. Whether an autoantibody or antibody against CABYR could matter depends on whether native CABYR is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

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

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