Seroatlas · Human Serome Atlas

C9orf40

Uncharacterized protein C9orf40

Also known as: CI040_HUMAN, FLJ10110

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

Protein identityUniProt · HPA

UniProt accession
Q8IXQ3
Gene
C9orf40
Ensembl
ENSG00000135045
Chromosome
9
Canonical length
194 aa
Protein class
Predicted intracellular proteins
Subcellular location
Nucleoplasm,Centrosome,Cytosol

OverviewNCBI Gene

No narrative summary is available for C9orf40 in this catalog release; identity and structured annotations are shown without generated factual claims.

Canonical amino-acid sequenceUniProt

194 residues, UniProt reviewed canonical sequence.

>Q8IXQ3|C9orf40
     1  MAKRRAAEPV TFHVPWKRLL LCDFAEQPPP PPLWIRPPGV AHAGQLLGVP EQHRKRKIDA
    61  GTMAEPSASP SKRRDSGDNS APSGQEREDH GLETGDPPLP PPPVLPGPGE ELPGARLPGG
   121  GGDDGAGRAG PPRGDWGVAS RQHNEEFWQY NTFQYWRNPL PPIDLADIED LSEDTLTEAT
   181  LQGRNEGAEV DMES

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against C9orf40 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
0
Mean surface accessibility (rSASA)
0.71
Highest tissue expression
11 nTPM

Expression across tissuesHPA

Tissue

  • testis: 11 nTPM
  • small intestine: 11 nTPM
  • spinal cord: 8 nTPM
  • duodenum: 7.9 nTPM
  • retina: 7.3 nTPM
  • cerebral cortex: 6.5 nTPM

Single-cell type

  • erythrocyte progenitors: 75 nCPM
  • late primary spermatocytes: 37 nCPM
  • early primary spermatocytes: 32 nCPM
  • migrating cytotrophoblasts: 30 nCPM
  • extravillous trophoblasts: 28 nCPM
  • cytotrophoblasts: 27 nCPM

Immune cell

  • eosinophil: 2.1 nTPM
  • memory B-cell: 0.8 nTPM
  • naive CD4 T-cell: 0.7 nTPM
  • basophil: 0.6 nTPM
  • naive B-cell: 0.5 nTPM
  • naive CD8 T-cell: 0.4 nTPM

Brain region

  • white matter: 9.8 nTPM
  • medulla oblongata: 8 nTPM
  • spinal cord: 7.8 nTPM
  • hypothalamus: 7.5 nTPM
  • pons: 7.5 nTPM
  • cerebral cortex: 7.2 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)
1.49
gnomAD pLI
0.07
gnomAD missense Z
1
DepMap mean gene effect
0.02
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 5% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads C9orf40 as an antibody target. Whether an autoantibody or antibody against C9orf40 could matter depends on whether native C9orf40 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

C9orf40 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 C9orf40 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/C9orf40. 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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