Seroatlas · Human Serome Atlas

CTSC

Dipeptidyl peptidase 1

Also known as: CATC_HUMAN, DPP1, PALS, PLS

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

Protein identityUniProt · HPA

UniProt accession
P53634
Gene
CTSC
Ensembl
ENSG00000109861
Chromosome
11
Canonical length
463 aa
Protein class
Disease related genes, Enzymes, Human disease related genes, Metabolic proteins, Plasma proteins, Potential drug targets, Predicted intracellular proteins, Predicted membrane proteins
Subcellular location
Vesicles
Secretome location
Intracellular and membrane

OverviewNCBI Gene

This gene encodes a member of the peptidase C1 family and lysosomal cysteine proteinase that appears to be a central coordinator for activation of many serine proteinases in cells of the immune system. Alternative splicing results in multiple transcript variants, at least one of which encodes a preproprotein that is proteolytically processed to generate heavy and light chains that form a disulfide-linked dimer. A portion of the propeptide acts as an intramolecular chaperone for the folding and stabilization of the mature enzyme. This enzyme requires chloride ions for activity and can degrade glucagon. Defects in the encoded protein have been shown to be a cause of Papillon-Lefevre syndrome, an autosomal recessive disorder characterized by palmoplantar keratosis and periodontitis. [provided by RefSeq, Nov 2015]

Canonical amino-acid sequenceUniProt

463 residues, UniProt reviewed canonical sequence.

>P53634|CTSC
     1  MGAGPSLLLA ALLLLLSGDG AVRCDTPANC TYLDLLGTWV FQVGSSGSQR DVNCSVMGPQ
    61  EKKVVVYLQK LDTAYDDLGN SGHFTIIYNQ GFEIVLNDYK WFAFFKYKEE GSKVTTYCNE
   121  TMTGWVHDVL GRNWACFTGK KVGTASENVY VNIAHLKNSQ EKYSNRLYKY DHNFVKAINA
   181  IQKSWTATTY MEYETLTLGD MIRRSGGHSR KIPRPKPAPL TAEIQQKILH LPTSWDWRNV
   241  HGINFVSPVR NQASCGSCYS FASMGMLEAR IRILTNNSQT PILSPQEVVS CSQYAQGCEG
   301  GFPYLIAGKY AQDFGLVEEA CFPYTGTDSP CKMKEDCFRY YSSEYHYVGG FYGGCNEALM
   361  KLELVHHGPM AVAFEVYDDF LHYKKGIYHH TGLRDPFNPF ELTNHAVLLV GYGTDSASGM
   421  DYWIVKNSWG TGWGENGYFR IRRGTDECAI ESIAVAATPI PKL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CTSC 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)
0.25
Highest tissue expression
257 nTPM

Expression across tissuesHPA

Tissue

  • lung: 257 nTPM
  • placenta: 238 nTPM
  • lymph node: 228 nTPM
  • kidney: 219 nTPM
  • spleen: 186 nTPM
  • rectum: 180 nTPM

Single-cell type

  • hofbauer cells: 2,041 nCPM
  • respiratory secretory cells: 627 nCPM
  • kupffer cells: 598 nCPM
  • pdcs: 544 nCPM
  • cytotrophoblasts: 535 nCPM
  • macrophages: 531 nCPM

Immune cell

  • non-classical monocyte: 586 nTPM
  • plasmacytoid DC: 426 nTPM
  • intermediate monocyte: 416 nTPM
  • eosinophil: 311 nTPM
  • total PBMC: 243 nTPM
  • gdT-cell: 231 nTPM

Brain region

  • white matter: 60 nTPM
  • thalamus: 58 nTPM
  • choroid plexus: 45 nTPM
  • medulla oblongata: 45 nTPM
  • pons: 43 nTPM
  • spinal cord: 39 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about CTSC.

Disease | AllUniProt

Conditions CTSC is implicated in, by any mechanism.

Disease | GeneticClinVar

86 pathogenic / likely-pathogenic of 571 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Papillon-Lefèvre syndrome
  • Periodontitis, aggressive
  • Haim-Munk syndrome
  • CTSC-related disorder
  • Periodontitis, aggressive 1

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)
1.03
gnomAD pLI
0
gnomAD missense Z
-0.14
DepMap mean gene effect
0.12
DepMap dependency class
none

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

Antibody and autoantibody relevanceSeroatlas analysis

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

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

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