Seroatlas · Human Serome Atlas

CTSA

Lysosomal protective protein

Also known as: GSL, PPGB, PPGB_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P10619
Gene
CTSA
Ensembl
ENSG00000064601
Chromosome
20
Canonical length
480 aa
Protein class
Disease related genes, Enzymes, Human disease related genes, Metabolic proteins, Potential drug targets, Predicted intracellular proteins
Subcellular location
Vesicles
Secretome location
Intracellular and membrane

OverviewNCBI Gene

This gene encodes a member of the peptidase S10 family of serine carboxypeptidases. Alternative splicing results in multiple transcript variants, at least one of which encodes a preproprotein that is proteolytically processed to generate two chains that comprise the heterodimeric active enzyme. This enzyme possesses deamidase, esterase and carboxypeptidase activities and acts as a scaffold in the lysosomal multienzyme complex. Mutations in this gene are associated with galactosialidosis. [provided by RefSeq, Nov 2015]

Canonical amino-acid sequenceUniProt

480 residues, UniProt reviewed canonical sequence.

>P10619|CTSA
     1  MIRAAPPPLF LLLLLLLLLV SWASRGEAAP DQDEIQRLPG LAKQPSFRQY SGYLKGSGSK
    61  HLHYWFVESQ KDPENSPVVL WLNGGPGCSS LDGLLTEHGP FLVQPDGVTL EYNPYSWNLI
   121  ANVLYLESPA GVGFSYSDDK FYATNDTEVA QSNFEALQDF FRLFPEYKNN KLFLTGESYA
   181  GIYIPTLAVL VMQDPSMNLQ GLAVGNGLSS YEQNDNSLVY FAYYHGLLGN RLWSSLQTHC
   241  CSQNKCNFYD NKDLECVTNL QEVARIVGNS GLNIYNLYAP CAGGVPSHFR YEKDTVVVQD
   301  LGNIFTRLPL KRMWHQALLR SGDKVRMDPP CTNTTAASTY LNNPYVRKAL NIPEQLPQWD
   361  MCNFLVNLQY RRLYRSMNSQ YLKLLSSQKY QILLYNGDVD MACNFMGDEW FVDSLNQKME
   421  VQRRPWLVKY GDSGEQIAGF VKEFSHIAFL TIKGAGHMVP TDKPLAAFTM FSRFLNKQPY

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CTSA 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)
0.23
Highest tissue expression
312 nTPM

Expression across tissuesHPA

Tissue

  • adrenal gland: 312 nTPM
  • colon: 169 nTPM
  • kidney: 166 nTPM
  • choroid plexus: 164 nTPM
  • rectum: 161 nTPM
  • parathyroid gland: 99 nTPM

Single-cell type

  • platelets: 2,264 nCPM
  • colonocytes: 325 nCPM
  • enterocytes: 283 nCPM
  • hofbauer cells: 247 nCPM
  • esophageal apical cells: 203 nCPM
  • kupffer cells: 182 nCPM

Immune cell

  • eosinophil: 531 nTPM
  • basophil: 482 nTPM
  • total PBMC: 377 nTPM
  • classical monocyte: 306 nTPM
  • MAIT T-cell: 186 nTPM
  • intermediate monocyte: 169 nTPM

Brain region

  • choroid plexus: 126 nTPM
  • thalamus: 77 nTPM
  • white matter: 69 nTPM
  • cerebellum: 59 nTPM
  • hypothalamus: 58 nTPM
  • medulla oblongata: 55 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about CTSA.

Disease | AllUniProt

Conditions CTSA is implicated in, by any mechanism.

Disease | GeneticClinVar

80 pathogenic / likely-pathogenic of 624 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Combined deficiency of sialidase AND beta galactosidase
  • GALACTOSIALIDOSIS, LATE INFANTILE
  • GALACTOSIALIDOSIS, ADULT
  • GALACTOSIALIDOSIS, EARLY INFANTILE
  • Non-immune hydrops fetalis

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)
0.88
gnomAD pLI
0
gnomAD missense Z
0.48
DepMap mean gene effect
0.06
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 10% 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 CTSA 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 CTSA as an antibody target. Whether an autoantibody or antibody against CTSA could matter depends on whether native CTSA is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

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

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