Seroatlas · Human Serome Atlas

KRTAP20-4

Putative keratin-associated protein 20-4

Also known as: KAP20.4, KR204_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q3LI62
Gene
KRTAP20-4
Ensembl
ENSG00000206105
Chromosome
21
Canonical length
44 aa
Protein class
Predicted intracellular proteins

OverviewNCBI Gene

Predicted to be located in intermediate filament. [provided by Alliance of Genome Resources, Jul 2025]

Canonical amino-acid sequenceUniProt

44 residues, UniProt reviewed canonical sequence.

>Q3LI62|KRTAP20-4
     1  MSYYSHLSGG LGCGLAVAVT MGRTVAVAEY GRCRHGCHSS YSAR

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against KRTAP20-4 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)
0.62
Highest tissue expression
1.9 nTPM

Expression across tissuesHPA

Tissue

  • testis: 1.9 nTPM
  • adipose tissue: 0 nTPM
  • adrenal gland: 0 nTPM
  • amygdala: 0 nTPM
  • appendix: 0 nTPM
  • basal ganglia: 0 nTPM

Single-cell type

  • gonadotrophs: 2.9 nCPM
  • differentiating spermatogonia: 2 nCPM
  • late primary spermatocytes: 1.3 nCPM
  • early primary spermatocytes: 0.7 nCPM
  • early spermatids: 0.6 nCPM
  • undifferentiated spermatogonia: 0.6 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

  • cerebral cortex: 0.4 nTPM
  • hippocampal formation: 0.4 nTPM
  • midbrain: 0.4 nTPM
  • basal ganglia: 0.3 nTPM
  • medulla oblongata: 0.3 nTPM
  • pons: 0.3 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 missense Z
0.65

OntologyGO

Cellular components

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads KRTAP20-4 as an antibody target. Whether an autoantibody or antibody against KRTAP20-4 could matter depends on whether native KRTAP20-4 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

KRTAP20-4 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 KRTAP20-4 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/KRTAP20-4. 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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