Seroatlas · Human Serome Atlas

KRTAP9-3

Keratin-associated protein 9-3

Also known as: KAP9.3, KRA93_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q9BYQ3
Gene
KRTAP9-3
Ensembl
ENSG00000204873
Chromosome
17
Canonical length
159 aa
Protein class
Predicted intracellular proteins

OverviewNCBI Gene

This protein is a member of the keratin-associated protein (KAP) family. The KAP proteins form a matrix of keratin intermediate filaments which contribute to the structure of hair fibers. KAP family members appear to have unique, family-specific amino- and carboxyl-terminal regions and are subdivided into three multi-gene families according to amino acid composition: the high sulfur, the ultrahigh sulfur, and the high tyrosine/glycine KAPs. This protein is a member of the ultrahigh sulfur KAP family and the gene is localized to a cluster of KAPs at 17q12-q21. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

159 residues, UniProt reviewed canonical sequence.

>Q9BYQ3|KRTAP9-3
     1  MTHCCSPCCQ PTCCRTTCWQ PTTVTTCSST PCCQPSCCVS SCCQPCCHPT CCQNTCCRTT
    61  CCQPICVTSC CQPSCCSTPC CQPTCCGSSC GQSSSCAPVY CRRTCYHPTS VCLPGCLNQS
   121  CGSNCCQPCC RPACCETTCC RTTCFQPTCV YSCCQPSCC

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against KRTAP9-3 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
Intracellular
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.66
Highest tissue expression
45 nTPM

Expression across tissuesHPA

Tissue

  • skin: 45 nTPM
  • salivary gland: 0.4 nTPM
  • adipose tissue: 0 nTPM
  • adrenal gland: 0 nTPM
  • amygdala: 0 nTPM
  • appendix: 0 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

  • 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

  • amygdala: 0 nTPM
  • basal ganglia: 0 nTPM
  • cerebellum: 0 nTPM
  • cerebral cortex: 0 nTPM
  • choroid plexus: 0 nTPM
  • hippocampal formation: 0 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
-1.54

OntologyGO

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads KRTAP9-3 as an antibody target. Whether an autoantibody or antibody against KRTAP9-3 could matter depends on whether native KRTAP9-3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

KRTAP9-3 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 KRTAP9-3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/KRTAP9-3. 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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