Seroatlas · Human Serome Atlas

C21orf140

Uncharacterized protein C21orf140

Also known as: F243A_HUMAN, FAM243A

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

Protein identityUniProt · HPA

UniProt accession
B9A014
Gene
C21orf140
Ensembl
ENSG00000222018
Chromosome
21
Canonical length
251 aa
Protein class
Predicted intracellular proteins

OverviewNCBI Gene

No narrative summary is available for C21orf140 in this catalog release; identity and structured annotations are shown without generated factual claims.

Canonical amino-acid sequenceUniProt

251 residues, UniProt reviewed canonical sequence.

>B9A014|C21orf140
     1  MPRFASPLLR NVIIRSQFDG IKRKQCLQYL KTLRTLQYDG FKTVYFGETN IPESLVTGED
    61  ISDGYFIQTP TWCIVHAAGS QGWVPWKYRV FLRDELCIKQ EDSLFSEFCD VVRKAYGKCV
   121  IVVKERRQQE EQRPKEDREA EGQFYIPTVI SLASIMCCPE VAKSCGHELL SLPSPCNYLN
   181  PLDSAWSSLK WFIINNRNEF CLQSIDSGYS YQCILFSNLI SKGIERINAS KWRTLTSKVR
   241  RWENYYLGKF S

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against C21orf140 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)
0.35
Highest tissue expression
4 nTPM

Expression across tissuesHPA

Tissue

  • retina: 4 nTPM
  • stomach: 3.7 nTPM
  • testis: 3.7 nTPM
  • cerebral cortex: 3.3 nTPM
  • skeletal muscle: 2.6 nTPM
  • thyroid gland: 1.9 nTPM

Single-cell type

  • adipocytes: 0 nCPM
  • adrenal cortex cells: 0 nCPM
  • adrenal medulla cells: 0 nCPM
  • alveolar cells type 1: 0 nCPM
  • alveolar cells type 2: 0 nCPM
  • astrocytes: 0 nCPM

Immune cell

  • naive CD4 T-cell: 0.1 nTPM
  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM

Brain region

  • choroid plexus: 12 nTPM
  • white matter: 12 nTPM
  • cerebral cortex: 12 nTPM
  • hippocampal formation: 12 nTPM
  • cerebellum: 11 nTPM
  • basal ganglia: 10 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)
1.24
gnomAD pLI
0.01
gnomAD missense Z
1.29
DepMap mean gene effect
0.1
DepMap dependency class
none

Protein domainsUniProt · Pfam · InterPro

  • Uncharacterized protein C21orf140-like

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads C21orf140 as an antibody target. Whether an autoantibody or antibody against C21orf140 could matter depends on whether native C21orf140 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

C21orf140 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 C21orf140 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/C21orf140. 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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