Seroatlas · Human Serome Atlas

ARHGEF9

Rho guanine nucleotide exchange factor 9

Also known as: ARHG9_HUMAN, KIAA0424, PEM-2

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

Protein identityUniProt · HPA

UniProt accession
O43307
Gene
ARHGEF9
Ensembl
ENSG00000131089
Chromosome
X
Canonical length
516 aa
Protein class
Disease related genes, Human disease related genes, Predicted intracellular proteins
Subcellular location
Cytosol

OverviewNCBI Gene

The protein encoded by this gene is a Rho-like GTPase that switches between the active (GTP-bound) state and inactive (GDP-bound) state to regulate CDC42 and other genes. This brain-specific protein also acts as an adaptor protein for the recruitment of gephyrin and together these proteins facilitate receceptor recruitement in GABAnergic and glycinergic synapses. Defects in this gene are the cause of startle disease with epilepsy (STHEE), also known as hyperekplexia with epilepsy, as well as several other types of cognitive disability. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2017]

Canonical amino-acid sequenceUniProt

516 residues, UniProt reviewed canonical sequence.

>O43307|ARHGEF9
     1  MTLLITGDSI VSAEAVWDHV TMANRELAFK AGDVIKVLDA SNKDWWWGQI DDEEGWFPAS
    61  FVRLWVNQED EVEEGPSDVQ NGHLDPNSDC LCLGRPLQNR DQMRANVINE IMSTERHYIK
   121  HLKDICEGYL KQCRKRRDMF SDEQLKVIFG NIEDIYRFQM GFVRDLEKQY NNDDPHLSEI
   181  GPCFLEHQDG FWIYSEYCNN HLDACMELSK LMKDSRYQHF FEACRLLQQM IDIAIDGFLL
   241  TPVQKICKYP LQLAELLKYT AQDHSDYRYV AAALAVMRNV TQQINERKRR LENIDKIAQW
   301  QASVLDWEGE DILDRSSELI YTGEMAWIYQ PYGRNQQRVF FLFDHQMVLC KKDLIRRDIL
   361  YYKGRIDMDK YEVVDIEDGR DDDFNVSMKN AFKLHNKETE EIHLFFAKKL EEKIRWLRAF
   421  REERKMVQED EKIGFEISEN QKRQAAMTVR KVPKQKGVNS ARSVPPSYPP PQDPLNHGQY
   481  LVPDGIAQSQ VFEFTEPKRS QSPFWQNFSR LTPFKK

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against ARHGEF9 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)
0.32
Highest tissue expression
82 nTPM

Expression across tissuesHPA

Tissue

  • retina: 82 nTPM
  • basal ganglia: 68 nTPM
  • cerebral cortex: 65 nTPM
  • hippocampal formation: 49 nTPM
  • hypothalamus: 44 nTPM
  • amygdala: 43 nTPM

Single-cell type

  • rod photoreceptor cells: 464 nCPM
  • cone photoreceptor cells: 383 nCPM
  • corticotrophs: 253 nCPM
  • breast lactating cells: 233 nCPM
  • retinal bipolar cells: 219 nCPM
  • brain inhibitory neurons: 165 nCPM

Immune cell

  • NK-cell: 8.5 nTPM
  • gdT-cell: 4.5 nTPM
  • naive CD4 T-cell: 3.3 nTPM
  • MAIT T-cell: 3.2 nTPM
  • memory CD8 T-cell: 3.1 nTPM
  • naive B-cell: 2.9 nTPM

Brain region

  • cerebral cortex: 144 nTPM
  • hippocampal formation: 134 nTPM
  • basal ganglia: 118 nTPM
  • hypothalamus: 115 nTPM
  • white matter: 91 nTPM
  • amygdala: 78 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about ARHGEF9.

Disease | AllUniProt

Conditions ARHGEF9 is implicated in, by any mechanism.

  • Developmental and epileptic encephalopathy 8 (DEE8) MIM:300607

Disease | GeneticClinVar

51 pathogenic / likely-pathogenic of 565 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

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)
0.15
gnomAD pLI
1
gnomAD missense Z
3.04
DepMap mean gene effect
-0.03
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% 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 ARHGEF9 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 ARHGEF9 as an antibody target. Whether an autoantibody or antibody against ARHGEF9 could matter depends on whether native ARHGEF9 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

ARHGEF9 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 ARHGEF9 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/ARHGEF9. 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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