Seroatlas · Human Serome Atlas

CYSTM1

Cysteine-rich and transmembrane domain-containing protein 1

Also known as: C5orf32, CYTM1_HUMAN, ORF1-FL49

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

Protein identityUniProt · HPA

UniProt accession
Q9H1C7
Gene
CYSTM1
Ensembl
ENSG00000120306
Chromosome
5
Canonical length
97 aa
Protein class
Predicted intracellular proteins

OverviewNCBI Gene

Located in extracellular exosome. [provided by Alliance of Genome Resources, Jul 2025]

Canonical amino-acid sequenceUniProt

97 residues, UniProt reviewed canonical sequence.

>Q9H1C7|CYSTM1
     1  MNQENPPPYP GPGPTAPYPP YPPQPMGPGP MGGPYPPPQG YPYQGYPQYG WQGGPQEPPK
    61  TTVYVVEDQR RDELGPSTCL TACWTALCCC CLWDMLT

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CYSTM1 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)
0.67
Highest tissue expression
1,242 nTPM

Expression across tissuesHPA

Tissue

  • stomach: 1,242 nTPM
  • kidney: 451 nTPM
  • skeletal muscle: 414 nTPM
  • choroid plexus: 364 nTPM
  • tongue: 336 nTPM
  • duodenum: 301 nTPM

Single-cell type

  • parietal cells: 5,546 nCPM
  • gastric chief cells: 3,255 nCPM
  • foveolar cells: 2,980 nCPM
  • late spermatids: 2,585 nCPM
  • neutrophils: 2,230 nCPM
  • mucous neck cells: 1,924 nCPM

Immune cell

  • neutrophil: 428 nTPM
  • plasmacytoid DC: 64 nTPM
  • myeloid DC: 41 nTPM
  • non-classical monocyte: 39 nTPM
  • intermediate monocyte: 37 nTPM
  • classical monocyte: 33 nTPM

Brain region

  • choroid plexus: 131 nTPM
  • hypothalamus: 74 nTPM
  • pons: 70 nTPM
  • midbrain: 67 nTPM
  • medulla oblongata: 67 nTPM
  • thalamus: 64 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)
0.9
gnomAD pLI
0.42
gnomAD missense Z
0.67
DepMap mean gene effect
0.07
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

Cellular components

Protein domainsUniProt · Pfam · InterPro

  • Cysteine-rich transmembrane domain
  • Cysteine-rich and transmembrane domain-containing protein 1-like
  • Cysteine-rich TM module stress tolerance

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads CYSTM1 as an antibody target. Whether an autoantibody or antibody against CYSTM1 could matter depends on whether native CYSTM1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CYSTM1 is annotated at the cell surface, where native CYSTM1 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 CYSTM1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CYSTM1. 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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