Seroatlas · Human Serome Atlas

ARHGAP21

Rho GTPase-activating protein 21

Also known as: ARHGAP10, KIAA1424, RHG21_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q5T5U3
Gene
ARHGAP21
Ensembl
ENSG00000107863
Chromosome
10
Canonical length
1958 aa
Protein class
Predicted intracellular proteins
Subcellular location
Plasma membrane,Cell Junctions,Actin filaments

OverviewNCBI Gene

ARHGAP21 functions preferentially as a GTPase-activating protein (GAP) for CDC42 (MIM 116952) and regulates the ARP2/3 complex (MIM 604221) and F-actin dynamics at the Golgi through control of CDC42 activity (Dubois et al., 2005 [PubMed 15793564]).[supplied by OMIM, Mar 2008]

Canonical amino-acid sequenceUniProt

1958 residues, UniProt reviewed canonical sequence.

>Q5T5U3|ARHGAP21
     1  MMATRRTGLS EGDGDKLKAC EVSKNKDGKE QSETVSLSED ETFSWPGPKT VTLKRTSQGF
    61  GFTLRHFIVY PPESAIQFSY KDEENGNRGG KQRNRLEPMD TIFVKQVKEG GPAFEAGLCT
   121  GDRIIKVNGE SVIGKTYSQV IALIQNSDTT LELSVMPKDE DILQVLQFTK DVTALAYSQD
   181  AYLKGNEAYS GNARNIPEPP PICYPWLPSA PSAMAQPVEI SPPDSSLSKQ QTSTPVLTQP
   241  GRAYRMEIQV PPSPTDVAKS NTAVCVCNES VRTVIVPSEK VVDLLSNRNN HTGPSHRTEE
   301  VRYGVSEQTS LKTVSRTTSP PLSIPTTHLI HQPAGSRSLE PSGILLKSGN YSGHSDGISS
   361  SRSQAVEAPS VSVNHYSPNS HQHIDWKNYK TYKEYIDNRR LHIGCRTIQE RLDSLRAASQ
   421  STTDYNQVVP NRTTLQGRRR STSHDRVPQS VQIRQRSVSQ ERLEDSVLMK YCPRSASQGA
   481  LTSPSVSFSN HRTRSWDYIE GQDETLENVN SGTPIPDSNG EKKQTYKWSG FTEQDDRRGI
   541  CERPRQQEIH KSFRGSNFTV APSVVNSDNR RMSGRGVGSV SQFKKIPPDL KTLQSNRNFQ
   601  TTCGMSLPRG ISQDRSPLVK VRSNSLKAPS THVTKPSFSQ KSFVSIKDQR PVNHLHQNSL
   661  LNQQTWVRTD SAPDQQVETG KSPSLSGASA KPAPQSSENA GTSDLELPVS QRNQDLSLQE
   721  AETEQSDTLD NKEAVILREK PPSGRQTPQP LRHQSYILAV NDQETGSDTT CWLPNDARRE
   781  VHIKRMEERK ASSTSPPGDS LASIPFIDEP TSPSIDHDIA HIPASAVISA STSQVPSIAT
   841  VPPCLTTSAP LIRRQLSHDH ESVGPPSLDA QPNSKTERSK SYDEGLDDYR EDAKLSFKHV
   901  SSLKGIKIAD SQKSSEDSGS RKDSSSEVFS DAAKEGWLHF RPLVTDKGKR VGGSIRPWKQ
   961  MYVVLRGHSL YLYKDKREQT TPSEEEQPIS VNACLIDISY SETKRKNVFR LTTSDCECLF
  1021  QAEDRDDMLA WIKTIQESSN LNEEDTGVTN RDLISRRIKE YNNLMSKAEQ LPKTPRQSLS
  1081  IRQTLLGAKS EPKTQSPHSP KEESERKLLS KDDTSPPKDK GTWRKGIPSI MRKTFEKKPT
  1141  ATGTFGVRLD DCPPAHTNRY IPLIVDICCK LVEERGLEYT GIYRVPGNNA AISSMQEELN
  1201  KGMADIDIQD DKWRDLNVIS SLLKSFFRKL PEPLFTNDKY ADFIEANRKE DPLDRLKTLK
  1261  RLIHDLPEHH YETLKFLSAH LKTVAENSEK NKMEPRNLAI VFGPTLVRTS EDNMTHMVTH
  1321  MPDQYKIVET LIQHHDWFFT EEGAEEPLTT VQEESTVDSQ PVPNIDHLLT NIGRTGVSPG
  1381  DVSDSATSDS TKSKGSWGSG KDQYSRELLV SSIFAAASRK RKKPKEKAQP SSSEDELDNV
  1441  FFKKENVEQC HNDTKEESKK ESETLGRKQK IIIAKENSTR KDPSTTKDEK ISLGKESTPS
  1501  EEPSPPHNSK HNKSPTLSCR FAILKESPRS LLAQKSSHLE ETGSDSGTLL STSSQASLAR
  1561  FSMKKSTSPE TKHSEFLANV STITSDYSTT SSATYLTSLD SSRLSPEVQS VAESKGDEAD
  1621  DERSELISEG RPVETDSESE FPVFPTALTS ERLFRGKLQE VTKSSRRNSE GSELSCTEGS
  1681  LTSSLDSRRQ LFSSHKLIEC DTLSRKKSAR FKSDSGSLGD AKNEKEAPSL TKVFDVMKKG
  1741  KSTGSLLTPT RGESEKQEPT WKTKIADRLK LRPRAPADDM FGVGNHKVNA ETAKRKSIRR
  1801  RHTLGGHRDA TEISVLNFWK VHEQSGERES ELSAVNRLKP KCSAQDLSIS DWLARERLRT
  1861  STSDLSRGEI GDPQTENPST REIATTDTPL SLHCNTGSSS STLASTNRPL LSIPPQSPDQ
  1921  INGESFQNVS KNASSAANAQ PHKLSETPGS KAEFHPCL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against ARHGAP21 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
Cell surface
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.58
Highest tissue expression
75 nTPM

Expression across tissuesHPA

Tissue

  • spinal cord: 75 nTPM
  • midbrain: 53 nTPM
  • hippocampal formation: 50 nTPM
  • cerebellum: 50 nTPM
  • cerebral cortex: 47 nTPM
  • amygdala: 41 nTPM

Single-cell type

  • oligodendrocytes: 1,075 nCPM
  • platelets: 597 nCPM
  • bergmann glia: 574 nCPM
  • fibro-adipogenic progenitors: 475 nCPM
  • microglia: 453 nCPM
  • oligodendrocyte progenitor cells: 444 nCPM

Immune cell

  • basophil: 0.9 nTPM
  • naive CD4 T-cell: 0.6 nTPM
  • eosinophil: 0.4 nTPM
  • intermediate monocyte: 0.4 nTPM
  • plasmacytoid DC: 0.4 nTPM
  • T-reg: 0.4 nTPM

Brain region

  • white matter: 261 nTPM
  • basal ganglia: 197 nTPM
  • medulla oblongata: 194 nTPM
  • pons: 175 nTPM
  • midbrain: 174 nTPM
  • cerebellum: 162 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about ARHGAP21.

Disease | GeneticClinVar

1 pathogenic / likely-pathogenic of 331 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)
0.2
gnomAD pLI
1
gnomAD missense Z
0.96
DepMap mean gene effect
-0.11
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 ARHGAP21 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 ARHGAP21 as an antibody target. Whether an autoantibody or antibody against ARHGAP21 could matter depends on whether native ARHGAP21 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

ARHGAP21 is annotated at the cell surface, where native ARHGAP21 is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label ARHGAP21 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/ARHGAP21. 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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