Seroatlas · Human Serome Atlas

CNTNAP3

Contactin-associated protein-like 3

Also known as: CASPR3, CNTNAP3A, CNTP3_HUMAN, FLJ14195, KIAA1714

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

Protein identityUniProt · HPA

UniProt accession
Q9BZ76
Gene
CNTNAP3
Ensembl
ENSG00000106714
Chromosome
9
Canonical length
1288 aa
Protein class
Predicted intracellular proteins, Predicted membrane proteins
Secretome location
Intracellular and membrane

OverviewNCBI Gene

The protein encoded by this gene belongs to the NCP family of cell-recognition molecules. This family represents a distinct subgroup of the neurexins. NCP proteins mediate neuron-glial interactions in vertebrates and glial-glial contact in invertebrates. The protein encoded by this gene may play a role in cell recognition within the nervous system. Alternatively spliced transcript variants encoding different isoforms have been described but their biological nature has not been determined. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

1288 residues, UniProt reviewed canonical sequence.

>Q9BZ76|CNTNAP3
     1  MASVAWAVLK VLLLLPTQTW SPVGAGNPPD CDAPLASALP RSSFSSSSEL SSSHGPGFSR
    61  LNRRDGAGGW TPLVSNKYQW LQIDLGERME VTAVATQGGY GSSDWVTSYL LMFSDGGRNW
   121  KQYRREESIW GFPGNTNADS VVHYRLQPPF EARFLRFLPL AWNPRGRIGM RIEVYGCAYK
   181  SEVVYFDGQS ALLYRLDKKP LKPIRDVISL KFKAMQSNGI LLHREGQHGN HITLELIKGK
   241  LVFFLNSGNA KLPSTIAPVT LTLGSLLDDQ HWHSVLIELL DTQVNFTVDK HTHHFQAKGD
   301  SSYLDLNFEI SFGGIPTPGR SRAFRRKSFH GCLENLYYNG VDVTELAKKH KPQILMMGNV
   361  SFSCPQPQTV PVTFLSSRSY LALPGNSGED KVSVTFQFRT WNRAGHLLFG ELRRGSGSFV
   421  LFLKDGKLKL SLFQPGQSPR NVTAGAGLND GQWHSVSFSA KWSHMNVVVD DDTAVQPLVA
   481  VLIDSGDTYY FGGCLDNSSG SGCKSPLGGF QGCLRLITIG DKAVDPILVQ QGALGSFRDL
   541  QIDSCGITDR CLPSYCEHGG ECSQSWDTFS CDCLGTGYTG ETCHSSLYEQ SCEAHKHRGN
   601  PSGLYYIDAD GSGPLGPFLV YCNMTADAAW TVVQHGGPDA VTLRGAPSGH PRSAVSFAYA
   661  AGAGQLRSAV NLAERCEQRL ALRCGTARRP DSRDGTPLSW WVGRTNETHT SWGGSLPDAQ
   721  KCTCGLEGNC IDSQYYCNCD AGRNEWTSDT IVLSQKEHLP VTQIVMTDAG RPHSEAAYTL
   781  GPLLCRGDQS FWNSASFNTE TSYLHFPAFH GELTADVCFF FKTTVSSGVF MENLGITDFI
   841  RIELRAPTEV TFSFDVGNGP CEVTVQSPTP FNDNQWHHVR AERNVKGASL QVDQLPQKMQ
   901  PAPADGHVRL QLNSQLFIGG TATRQRGFLG CIRSLQLNGV ALDLEERATV TPGVEPGCAG
   961  HCSTYGHLCR NGGRCREKRR GVTCDCAFSA YDGPFCSNEI SAYFATGSSM TYHFQEHYTL
  1021  SENSSSLVSS LHRDVTLTRE MITLSFRTTR TPSLLLYVSS FYEEYLSVIL ANNGSLQIRY
  1081  KLDRHQNPDA FTFDFKNMAD GQLHQVKINR EEAVVMVEVN QSTKKQVILS SGTEFNAVKS
  1141  LILGKVLEAA GADPDTRRAA TSGFTGCLSA VRFGRAAPLK AALRPSGPSR VTVRGHVAPM
  1201  ARCAAGAASG SPARELAPRL AGGAGRSGPA DEGEPLVNAD RRDSAVIGGV IAVVIFILLC
  1261  ITAIAIRIYQ QRKLRKENES KVSKKEEC

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CNTNAP3 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
Cell surface
Secreted
No
Transmembrane segments
1
Mean surface accessibility (rSASA)
0.28
Highest tissue expression
6.8 nTPM

Expression across tissuesHPA

Tissue

  • skin: 6.8 nTPM
  • esophagus: 6.3 nTPM
  • basal ganglia: 5.5 nTPM
  • colon: 3.9 nTPM
  • heart muscle: 3.7 nTPM
  • choroid plexus: 3.6 nTPM

Single-cell type

  • neutrophils: 816 nCPM
  • neutrophil progenitors: 167 nCPM
  • cardiomyocytes: 117 nCPM
  • medullary thymic epithelial cells: 70 nCPM
  • lymphatic endothelial cells: 67 nCPM
  • salivary duct cells: 65 nCPM

Immune cell

  • neutrophil: 7.4 nTPM
  • eosinophil: 0.4 nTPM
  • basophil: 0.2 nTPM
  • classical monocyte: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM

Brain region

  • basal ganglia: 21 nTPM
  • midbrain: 18 nTPM
  • cerebral cortex: 16 nTPM
  • hypothalamus: 13 nTPM
  • hippocampal formation: 12 nTPM
  • white matter: 12 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)
0.77
gnomAD pLI
0
gnomAD missense Z
0.15
DepMap mean gene effect
-0.16
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

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads CNTNAP3 as an antibody target. Whether an autoantibody or antibody against CNTNAP3 could matter depends on whether native CNTNAP3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CNTNAP3 is annotated at the cell surface, where native CNTNAP3 is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label CNTNAP3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CNTNAP3. 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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