Selected-GenAtlas references SOURCE GeneCards NCBI Gene Swiss-Prot Orphanet Ensembl
HGNC UniGene Nucleotide OMIM UCSC
Home Page
Symbol ARX contributors: mct/pgu - updated : 08-02-2014
HGNC name aristaless related homeobox
HGNC id 18060
Corresponding disease
EIEE1 epileptic encephalopathy, early infantile, 1
ISSX infantile spasms syndrome with hypsarrhythmia
MRX54 mental retardation, 54
PRTS Partington mental retardation syndrome
XLAG lissencephaly, with ambiguous genitalia
Location Xp21.3      Physical location : 25.021.814 - 25.034.065
Synonym name
  • homeobox protein ARX
  • aristaless-related homeobox, X-linked
  • cancer/testis antigen 121
  • Synonym symbol(s) CT121
    TYPE functioning gene
    SPECIAL FEATURE component of a cluster
    STRUCTURE 11.56 kb     5 Exon(s)
    10 Kb 5' upstream gene genomic sequence study
    regulatory sequence cytosine-phosphate-guanine/HTF
    motif repetitive sequence   triplet
    text structure
  • expanded polyalanine
  • a high overall GC content of 72.5p100 that codes for a multidomain protein
  • MAPPING cloned Y linked N status provisional
    Map pter - DXS6717 - DXS1432 - ARX - DXS6714 - DXS8056 - cen
    Physical map
    MBTPS2 Xp22.1-p22.2 membrane-bound transcription factor protease, site 2 SMS Xp22.1 spermine synthase PHEX Xp22.2-p22.1 phosphate regulating gene with homologies to endopeptidases on the X chromosome (hypophosphatemia, vitamin D resistant rickets) FLJ25735 Xp22.13 hypothetical protein FLJ25735 LOC389841 X LOC389841 DDX53 Xp22 DEAD (Asp-Glu-Ala-Asp) box polypeptide 53 MGC45134 Xp22.13 hypothetical protein MGC45134 LOC392432 X similar to hypothetical protein MGC35083 FLJ30296 Xp22.13 hypothetical protein FLJ30296 PRDX4 Xp22.12-p21.3 peroxiredoxin 4 ACATE2 Xp22.13 likely ortholog of mouse acyl-Coenzyme A thioesterase 2, mitochondrial SAT Xp22.1 spermidine/spermine N1-acetyltransferase MGC4825 Xp22.13 hypothetical protein MGC4825 LOC317771 Xp22.1 ribosomal protein L9 pseudogene FLJ25444 Xp22.13 hypothetical protein FLJ25444 KIAA1677 Xp22.1-p21 KIAA1677 EIF2S3 Xp22.2-p22.1 eukaryotic translation initiation factor 2, subunit 3 gamma, 52kDa ZFX Xp22.13-p22.12 zinc finger protein, X-linked LOC347438 Xp22.13 similar to P38IP protein LOC170067 Xp22.13 similar to transcription factor (p38 interacting protein) LOC286513 Xp22.13 similar to 40S ribosomal protein S26 PDK3 Xp22,12 pyruvate dehydrogenase kinase, isoenzyme 3 PCYT1B Xp22.12 phosphate cytidylyltransferase 1, choline, beta isoform POLA Xp22.12 polymerase (DNA directed), alpha ARX Xp22.12 aristaless related homeobox LOC139957 Xp22.12 similar to platelet-activating factor acetylhydrolase, isoform Ib, beta subunit 30kDa; platelet-activating factor acetylhydrolase, isoform Ib, beta subunit (30kD); Platelet-activating factor acetylhydrolase, isoform Ib, beta subunit LOC220895 Xp22.12 similar to methyltransferase-like protein 1 isoform a; D1075-like gene product LOC389842 X similar to Ran-specific GTPase-activating protein (Ran binding protein 1) (RanBP1) MGC33889 Xp22.12 hypothetical protein MGC33889 LOC392433 X similar to melanoma antigen, family B, 6 MAGEB6 Xp22.11 similar to melanoma antigen, family B, 6 LOC347541 Xp22.12 similar to melanoma antigen 2 VENTX2P1 Xp22.12 VENT-like homeobox 2 pseudogene 1 LOC347543 Xp22.11 similar to 60S ribosomal protein L7 HMGA1L1 Xp22 high mobility group AT-hook 1-like 1 LOC139420 Xp22.11 similar to KIAA1387 protein RDXP2 Xp22.12 radixin pseudogene 2 FLJ32742 Xp22.11 hypothetical protein FLJ32742 LOC347442 Xp22.11 similar to H326 FLJ32965 Xp22.11 hypothetical protein FLJ32965 LOC392434 X similar to melanoma antigen LOC392435 X similar to melanoma antigen LOC392436 X similar to melanoma antigen MAGE LOC340569 Xp22.11 pseudogene of origin recognition complex, subunit 1-like LOC139425 Xp22.11 similar to H326
    TRANSCRIPTS type messenger
    identificationnb exonstypebpproduct
    ProteinkDaAAspecific expressionYearPubmed
    5 - 2885 - 562 - 1996 8826457
    Type restricted
       expressed in (based on citations)
    SystemOrgan level 1Organ level 2Organ level 3Organ level 4LevelPubmedSpeciesStageRna symbol
    Endocrinepancreas   highly
    Nervousbrainforebraincerebral cortex highly
     brainbasal nucleistriatum  
    Reproductivefemale systemovary   
     male systemtestis   
    SystemTissueTissue level 1Tissue level 2LevelPubmedSpeciesStageRna symbol
    SystemCellPubmedSpeciesStageRna symbol
    cell lineage
    cell lines
    at STAGE
    physiological period embryo, fetal
    Text brain, forebrain, floor plate, testis, strongly expressed in differentiating embryonic muscle
  • two independent repression domains: an N-terminal octapeptide motif/engrailed homology domain, necessary for Groucho-dependent repression activity
  • a high overall GC content of 72.5p100 that codes for a multidomain protein, including the octapeptide domain, that binds DNA
  • three nuclear localization sequences
  • four polyalanine tracts (pA1-4)
  • two repression domains, the OP and a second domain located in the C-terminus at amino acids (398-448) of the protein, termed ORD (for other repression domain)
  • C-terminal Aristaless domain, a novel octapeptide motif/engrailed homology domain, and four polyalanine (polyA) tracts, and missense mutations in the ARX homeodomain represent loss-of-function mutations, which lead to a reduced or complete loss of DNA binding and as a consequence, a loss of transcriptional repression
    interspecies ortholog to murine Arx
  • paired homeobox family
  • bicoid subfamily
  • CATEGORY transcription factor
    SUBCELLULAR LOCALIZATION     intracellular
    text restricted to regions that are known to be rich in GABAergic neurons
    basic FUNCTION
  • playing a role in the differentiation, radial and tangential migration and maintenance of specific neuronal subtypes in the cerebral cortex (crucial for the development of cognitive function) and a secondary role in the differentiation of the testes (controlling the function of Leydig cells)
  • acting as a novel positive regulator of embryonic myogenesis by synergizing with MEF2C and MYOD1 and by establishing an activating loop with myogenin
  • can function as a transcriptional repressor
  • important for many developmental processes, including proper migration of GABA-ergic cortical interneurons and neuronal cell differentiation and proliferation, and for proper pancreatic endocrine cell specification through the inhibition of PAX4
  • plays multiple roles in forebrain development, both dependent and independent of DLX1/2
  • may play a role in controlling cell cycle exit of neural progenitors within the subpallium
  • not directly involved in GABAergic cell fate specification, but having multiple and distinct cell-autonomous roles for ARX in corticogenesis
  • required for the normal development of human enteroendocrine cells, and in the progenitor for enteroendocrine cell development
  • CELLULAR PROCESS cell life, differentiation
    nucleotide, transcription
    a component
    small molecule
  • interacting with IPO13 (with the C-terminal nuclear localization sequences in the homeodomain of ARX is required for correct nuclear localization)
  • interaction between ARX and the co-repressors Groucho and CtBP
  • EBF3, LMO1 and SHOX2 are direct transcriptional targets of ARX (can bind to the putative enhancers of EBF3, LMO1 and SHOX2)
  • genetic interactions between NKX2-2 and ARX within the endocrine progenitor cells that ensure the correct specification and regulation of endocrine hormone-producing cells
  • LMO1 and SHOX2, are ARX targets (mutations in the ARX homeodomain disrupt repression of LMO1 and SHOX2, direct targets of ARX transcription repression)
  • KDM5C is directly regulated by ARX through the binding in a conserved noncoding element (ARX transactivates the 5prime KDM5C regulatory element by binding to the two “TAAT/ATTA” boxes (BD1 and BD2)
  • ARX is a direct target of NKX6.1
  • LHX6 directly binds to an ARX enhancer and to an intronic CXCR7 enhancer that remains active in mature interneurons
  • EBF3 is a downstream transcriptional target of aristaless-related homeobox (ARX) and is thought to be transcriptionally repressed by ARX
  • cell & other
    corresponding disease(s) ISSX , PRTS , XLAG , MRX54 , EIEE1
    Variant & Polymorphism
    Candidate gene
    Therapy target