Seroatlas · Human Serome Atlas

CRTAP

Cartilage-associated protein

Also known as: CASP, CRTAP_HUMAN, LEPREL3, P3H5

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

Protein identityUniProt · HPA

UniProt accession
O75718
Gene
CRTAP
Ensembl
ENSG00000170275
Chromosome
3
Canonical length
401 aa
Protein class
Disease related genes, Human disease related genes, Predicted secreted proteins
Subcellular location
Intermediate filaments,Actin filaments,Cytosol
Secretome location
Secreted to blood

OverviewNCBI Gene

The protein encoded by this gene is similar to the chicken and mouse CRTAP genes. The encoded protein is a scaffolding protein that may influence the activity of at least one member of the cytohesin/ARNO family in response to specific cellular stimuli. Defects in this gene are associated with osteogenesis imperfecta, a connective tissue disorder characterized by bone fragility and low bone mass. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

401 residues, UniProt reviewed canonical sequence.

>O75718|CRTAP
     1  MEPGRRGAAA LLALLCVACA LRAGRAQYER YSFRSFPRDE LMPLESAYRH ALDKYSGEHW
    61  AESVGYLEIS LRLHRLLRDS EAFCHRNCSA APQPEPAAGL ASYPELRLFG GLLRRAHCLK
   121  RCKQGLPAFR QSQPSREVLA DFQRREPYKF LQFAYFKANN LPKAIAAAHT FLLKHPDDEM
   181  MKRNMAYYKS LPGAEDYIKD LETKSYESLF IRAVRAYNGE NWRTSITDME LALPDFFKAF
   241  YECLAACEGS REIKDFKDFY LSIADHYVEV LECKIQCEEN LTPVIGGYPV EKFVATMYHY
   301  LQFAYYKLND LKNAAPCAVS YLLFDQNDKV MQQNLVYYQY HRDTWGLSDE HFQPRPEAVQ
   361  FFNVTTLQKE LYDFAKENIM DDDEGEVVEY VDDLLELEET S

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CRTAP 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)
0.32
Highest tissue expression
221 nTPM

Expression across tissuesHPA

Tissue

  • blood vessel: 221 nTPM
  • cervix: 161 nTPM
  • endometrium: 150 nTPM
  • adipose tissue: 148 nTPM
  • urinary bladder: 141 nTPM
  • colon: 135 nTPM

Single-cell type

  • decidual stromal cells: 195 nCPM
  • smooth muscle cells: 170 nCPM
  • kupffer cells: 166 nCPM
  • monocytes: 154 nCPM
  • vascular smooth muscle cells: 154 nCPM
  • hofbauer cells: 140 nCPM

Immune cell

  • classical monocyte: 378 nTPM
  • myeloid DC: 307 nTPM
  • total PBMC: 200 nTPM
  • intermediate monocyte: 148 nTPM
  • plasmacytoid DC: 83 nTPM
  • T-reg: 74 nTPM

Brain region

  • basal ganglia: 99 nTPM
  • white matter: 98 nTPM
  • spinal cord: 98 nTPM
  • thalamus: 94 nTPM
  • hypothalamus: 92 nTPM
  • medulla oblongata: 92 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about CRTAP.

Disease | AllUniProt

Conditions CRTAP is implicated in, by any mechanism.

Disease | GeneticClinVar

68 pathogenic / likely-pathogenic of 720 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)
0.86
gnomAD pLI
0
gnomAD missense Z
-0.44
DepMap mean gene effect
-0.09
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

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

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

CRTAP is annotated as secreted, so native CRTAP 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 CRTAP as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

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