Seroatlas · Human Serome Atlas

HOXA9

Homeobox protein Hox-A9

Also known as: HOX1, HOX1G, HXA9_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P31269
Gene
HOXA9
Ensembl
ENSG00000078399
Chromosome
7
Canonical length
272 aa
Protein class
Cancer-related genes, Disease related genes, Plasma proteins, Predicted intracellular proteins, Transcription factors
Subcellular location
Nucleoplasm

OverviewNCBI Gene

In vertebrates, the genes encoding the class of transcription factors called homeobox genes are found in clusters named A, B, C, and D on four separate chromosomes. Expression of these proteins is spatially and temporally regulated during embryonic development. This gene is part of the A cluster on chromosome 7 and encodes a DNA-binding transcription factor which may regulate gene expression, morphogenesis, and differentiation. This gene is highly similar to the abdominal-B (Abd-B) gene of Drosophila. A specific translocation event which causes a fusion between this gene and the NUP98 gene has been associated with myeloid leukemogenesis. Read-through transcription exists between this gene and the upstream homeobox A10 (HOXA10) gene.[provided by RefSeq, Mar 2011]

Canonical amino-acid sequenceUniProt

272 residues, UniProt reviewed canonical sequence.

>P31269|HOXA9
     1  MATTGALGNY YVDSFLLGAD AADELSVGRY APGTLGQPPR QAATLAEHPD FSPCSFQSKA
    61  TVFGASWNPV HAAGANAVPA AVYHHHHHHP YVHPQAPVAA AAPDGRYMRS WLEPTPGALS
   121  FAGLPSSRPY GIKPEPLSAR RGDCPTLDTH TLSLTDYACG SPPVDREKQP SEGAFSENNA
   181  ENESGGDKPP IDPNNPAANW LHARSTRKKR CPYTKHQTLE LEKEFLFNMY LTRDRRYEVA
   241  RLLNLTERQV KIWFQNRRMK MKKINKDRAK DE

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against HOXA9 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
27 nTPM

Expression across tissuesHPA

Tissue

  • kidney: 27 nTPM
  • skin: 24 nTPM
  • colon: 21 nTPM
  • fallopian tube: 20 nTPM
  • endometrium: 17 nTPM
  • skeletal muscle: 15 nTPM

Single-cell type

  • hematopoietic stem cells: 51 nCPM
  • prostatic club cells: 38 nCPM
  • epididymal principal cells: 37 nCPM
  • basal prostatic cells: 36 nCPM
  • prostatic hillock cells: 35 nCPM
  • podocytes: 30 nCPM

Immune cell

  • NK-cell: 12 nTPM
  • basophil: 6.7 nTPM
  • myeloid DC: 5.6 nTPM
  • plasmacytoid DC: 1.8 nTPM
  • gdT-cell: 1.3 nTPM
  • naive B-cell: 0.9 nTPM

Brain region

  • medulla oblongata: 0.5 nTPM
  • white matter: 0.5 nTPM
  • spinal cord: 0.4 nTPM
  • pons: 0.2 nTPM
  • amygdala: 0.1 nTPM
  • basal ganglia: 0.1 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)
1.62
gnomAD pLI
0
gnomAD missense Z
-0.06
DepMap mean gene effect
-0.15
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).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of HOXA9 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads HOXA9 as an antibody target. Whether an autoantibody or antibody against HOXA9 could matter depends on whether native HOXA9 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

HOXA9 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 HOXA9 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/HOXA9. 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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