Seroatlas · Human Serome Atlas

ALX4

Homeobox protein aristaless-like 4

Also known as: ALX4_HUMAN, FPP, KIAA1788, PFM, PFM2

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

Protein identityUniProt · HPA

UniProt accession
Q9H161
Gene
ALX4
Ensembl
ENSG00000052850
Chromosome
11
Canonical length
411 aa
Protein class
Disease related genes, Human disease related genes, Predicted intracellular proteins, Transcription factors
Subcellular location
Nucleoplasm

OverviewNCBI Gene

This gene encodes a paired-like homeodomain transcription factor expressed in the mesenchyme of developing bones, limbs, hair, teeth, and mammary tissue. Mutations in this gene cause parietal foramina 2 (PFM2); an autosomal dominant disease characterized by deficient ossification of the parietal bones. Mutations in this gene also cause a form of frontonasal dysplasia with alopecia and hypogonadism; suggesting a role for this gene in craniofacial development, mesenchymal-epithelial communication, and hair follicle development. Deletion of a segment of chromosome 11 containing this gene, del(11)(p11p12), causes Potocki-Shaffer syndrome (PSS); a syndrome characterized by craniofacial anomalies, cognitive disability, multiple exostoses, and genital abnormalities in males. In mouse, this gene has been shown to use dual translation initiation sites located 16 codons apart. [provided by RefSeq, Oct 2009]

Canonical amino-acid sequenceUniProt

411 residues, UniProt reviewed canonical sequence.

>Q9H161|ALX4
     1  MNAETCVSYC ESPAAAMDAY YSPVSQSREG SSPFRAFPGG DKFGTTFLSA AAKAQGFGDA
    61  KSRARYGAGQ QDLATPLESG AGARGSFNKF QPQPSTPQPQ PPPQPQPQQQ QPQPQPPAQP
   121  HLYLQRGACK TPPDGSLKLQ EGSSGHSAAL QVPCYAKESS LGEPELPPDS DTVGMDSSYL
   181  SVKEAGVKGP QDRASSDLPS PLEKADSESN KGKKRRNRTT FTSYQLEELE KVFQKTHYPD
   241  VYAREQLAMR TDLTEARVQV WFQNRRAKWR KRERFGQMQQ VRTHFSTAYE LPLLTRAENY
   301  AQIQNPSWLG NNGAASPVPA CVVPCDPVPA CMSPHAHPPG SGASSVTDFL SVSGAGSHVG
   361  QTHMGSLFGA ASLSPGLNGY ELNGEPDRKT SSIAALRMKA KEHSAAISWA T

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against ALX4 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)
0.65
Highest tissue expression
1.7 nTPM

Expression across tissuesHPA

Tissue

  • breast: 1.7 nTPM
  • choroid plexus: 1.5 nTPM
  • skeletal muscle: 0.9 nTPM
  • skin: 0.8 nTPM
  • salivary gland: 0.7 nTPM
  • endometrium: 0.5 nTPM

Single-cell type

  • ependymal cells: 17 nCPM
  • myosatellite cells: 17 nCPM
  • leydig cells: 17 nCPM
  • epicardial cells: 16 nCPM
  • choroid plexus epithelial cells: 8.9 nCPM
  • fibroblasts: 7.2 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

  • choroid plexus: 5.1 nTPM
  • midbrain: 1.8 nTPM
  • cerebral cortex: 1.7 nTPM
  • medulla oblongata: 1.5 nTPM
  • hippocampal formation: 1.3 nTPM
  • white matter: 1.2 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about ALX4.

Disease | AllUniProt

Conditions ALX4 is implicated in, by any mechanism.

Disease | GeneticClinVar

21 pathogenic / likely-pathogenic of 333 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Parietal foramina 2
  • Frontonasal dysplasia with alopecia and genital anomaly
  • Inborn genetic diseases
  • Craniosynostosis 5, susceptibility to
  • See cases

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)
0.52
gnomAD pLI
0.36
gnomAD missense Z
0.82
DepMap mean gene effect
-0.01
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% 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

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads ALX4 as an antibody target. Whether an autoantibody or antibody against ALX4 could matter depends on whether native ALX4 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

ALX4 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 ALX4 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/ALX4. 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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