C19orf18
Uncharacterized protein C19orf18
Also known as: CS018_HUMAN, MGC41906
Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene
Protein identityUniProt · HPA
- UniProt accession
- Q8NEA5
- Gene
- C19orf18
- Ensembl
- ENSG00000177025
- Chromosome
- 19
- Canonical length
- 215 aa
- Protein class
- Predicted membrane proteins
- Subcellular location
- Golgi apparatus
OverviewNCBI Gene
Located in extracellular exosome. [provided by Alliance of Genome Resources, Jul 2025]
Canonical amino-acid sequenceUniProt
215 residues, UniProt reviewed canonical sequence.
>Q8NEA5|C19orf18
1 MDKVQSGFLI LFLFLMECQL HLCLPYADGL HPTGNITGLP GSKRSQPPRN ITKEPKVFFH
61 KTQLPGIQGA ASRSTAASPT NPMKFLRNKA IIRHRPALVK VILISSVAFS IALICGMAIS
121 YMIYRLAQAE ERQQLESLYK NLRIPLLGDE EEGSEDEGES THLLPENENE LEKFIHSVII
181 SKRSKNIKKK LKEEQNSVTE NKTKNASHNG KMEDLLocalizationUniProt · AlphaFold · HPA
Whether an antibody against C19orf18 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
- Unknown
- Secreted
- No
- Transmembrane segments
- 1
- Mean surface accessibility (rSASA)
- 0.59
- Highest tissue expression
- 15 nTPM
Expression across tissuesHPA
Tissue
- choroid plexus: 15 nTPM
- testis: 12 nTPM
- retina: 4.8 nTPM
- heart muscle: 4.6 nTPM
- pituitary gland: 3.8 nTPM
- epididymis: 3.7 nTPM
Single-cell type
- early spermatids: 135 nCPM
- late primary spermatocytes: 122 nCPM
- choroid plexus epithelial cells: 66 nCPM
- ependymal cells: 49 nCPM
- myonuclei: 47 nCPM
- sertoli cells: 42 nCPM
Immune cell
- memory B-cell: 0.5 nTPM
- myeloid DC: 0.3 nTPM
- memory CD4 T-cell: 0.2 nTPM
- naive B-cell: 0.2 nTPM
- naive CD8 T-cell: 0.2 nTPM
- non-classical monocyte: 0.2 nTPM
Brain region
- choroid plexus: 11 nTPM
- medulla oblongata: 6.8 nTPM
- midbrain: 6.7 nTPM
- basal ganglia: 5.5 nTPM
- thalamus: 5.5 nTPM
- spinal cord: 5.2 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)
- 1.6
- gnomAD pLI
- 0
- gnomAD missense Z
- 0.1
- DepMap mean gene effect
- -0.05
- 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
Cellular components
Protein domainsUniProt · Pfam · InterPro
- Uncharacterized protein C19orf18
- Family of unknown function (DUF5534)
KeywordsUniProt
Antibody and autoantibody relevanceSeroatlas analysis
Seroatlas reads C19orf18 as an antibody target. Whether an autoantibody or antibody against C19orf18 could matter depends on whether native C19orf18 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.
C19orf18 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 C19orf18 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.
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