Seroatlas · Human Serome Atlas

CST8

Cystatin-8

Also known as: CRES, CST8_HUMAN, CTES5

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

Protein identityUniProt · HPA

UniProt accession
O60676
Gene
CST8
Ensembl
ENSG00000125815
Chromosome
20
Canonical length
142 aa
Protein class
Predicted secreted proteins
Secretome location
Secreted in male reproductive system

OverviewNCBI Gene

The cystatin superfamily encompasses proteins that contain multiple cystatin-like sequences. Some of the members are active cysteine protease inhibitors, while others have lost or perhaps never acquired this inhibitory activity. There are three inhibitory families in the superfamily, including the type 1 cystatins (stefins), type 2 cystatins and the kininogens. The type 2 cystatin proteins are a class of cysteine proteinase inhibitors found in a variety of human fluids and secretions. The cystatin locus on chromosome 20 contains the majority of the type 2 cystatin genes and pseudogenes. This gene is located in the cystatin locus and encodes a protein similar to type 2 cystatins. The encoded protein exhibits highly tissue-specific expression in the reproductive tract, suggesting implicit roles in reproduction. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Aug 2013]

Canonical amino-acid sequenceUniProt

142 residues, UniProt reviewed canonical sequence.

>O60676|CST8
     1  MPRCRWLSLI LLTIPLALVA RKDPKKNETG VLRKLKPVNA SNANVKQCLW FAMQEYNKES
    61  EDKYVFLVVK TLQAQLQVTN LLEYLIDVEI ARSDCRKPLS TNEICAIQEN SKLKRKLSCS
   121  FLVGALPWNG EFTVMEKKCE DA

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CST8 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)
0.41
Highest tissue expression
22 nTPM

Expression across tissuesHPA

Tissue

  • testis: 22 nTPM
  • retina: 0.1 nTPM
  • adipose tissue: 0 nTPM
  • adrenal gland: 0 nTPM
  • amygdala: 0 nTPM
  • appendix: 0 nTPM

Single-cell type

  • early spermatids: 260 nCPM
  • late spermatids: 149 nCPM
  • late primary spermatocytes: 5.3 nCPM
  • leydig cells: 1.3 nCPM
  • esophageal apical cells: 1.1 nCPM
  • peritubular myoid cells: 0.7 nCPM

Immune cell

  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM
  • MAIT T-cell: 0 nTPM

Brain region

  • amygdala: 0 nTPM
  • basal ganglia: 0 nTPM
  • cerebellum: 0 nTPM
  • cerebral cortex: 0 nTPM
  • choroid plexus: 0 nTPM
  • hippocampal formation: 0 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)
1.65
gnomAD pLI
0
gnomAD missense Z
-1.26
DepMap mean gene effect
0.09
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads CST8 as an antibody target. Whether an autoantibody or antibody against CST8 could matter depends on whether native CST8 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CST8 is annotated as secreted, so native CST8 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 CST8 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CST8. 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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