Seroatlas · Human Serome Atlas

ADAM21

Disintegrin and metalloproteinase domain-containing protein 21

Also known as: ADA21_HUMAN, ADAM31

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

Protein identityUniProt · HPA

UniProt accession
Q9UKJ8
Gene
ADAM21
Ensembl
ENSG00000139985
Chromosome
14
Canonical length
722 aa
Protein class
Predicted membrane proteins

OverviewNCBI Gene

This gene encodes a member of the ADAM (a disintegrin and metalloprotease domain) family. Members of this family are membrane-anchored proteins structurally related to snake venom disintegrins, and have been implicated in a variety of biological processes involving cell-cell and cell-matrix interactions, including fertilization, muscle development, and neurogenesis. The expression of this gene expression is testis-specific. [provided by RefSeq, May 2011]

Canonical amino-acid sequenceUniProt

722 residues, UniProt reviewed canonical sequence.

>Q9UKJ8|ADAM21
     1  MAVDGTLVYI RVTLLLLWLG VFLSISGYCQ AGPSQHFTSP EVVIPLKVIS RGRSAKAPGW
    61  LSYSLRFGGQ KHVVHMRVKK LLVSRHLPVF TYTDDRALLE DQLFIPDDCY YHGYVEAAPE
   121  SLVVFSACFG GFRGVLKISG LTYEIEPIRH SATFEHLVYK INSNETQFPA MRCGLTEKEV
   181  ARQQLEFEEA ENSALEPKSA GDWWTHAWFL ELVVVVNHDF FIYSQSNISK VQEDVFLVVN
   241  IVDSMYKQLG TYIILIGIEI WNQGNVFPMT SIEQVLNDFS QWKQISLSQL QHDAAHMFIK
   301  NSLISILGLA YVAGICRPPI DCGVDNFQGD TWSLFANTVA HELGHTLGMQ HDEEFCFCGE
   361  RGCIMNTFRV PAEKFTNCSY ADFMKTTLNQ GSCLHNPPRL GEIFMLKRCG NGVVEREEQC
   421  DCGSVQQCEQ DACCLLNCTL RPGAACAFGL CCKDCKFMPS GELCRQEVNE CDLPEWCNGT
   481  SHQCPEDRYV QDGIPCSDSA YCYQKRCNNH DQHCREIFGK DAKSASQNCY KEINSQGNRF
   541  GHCGINGTTY LKCHISDVFC GRVQCENVRD IPLLQDHFTL QHTHINGVTC WGIDYHLRMN
   601  ISDIGEVKDG TVCGPGKICI HKKCVSLSVL SHVCLPETCN MKGICNNKHH CHCGYGWSPP
   661  YCQHRGYGGS IDSGPASAKR GVFLPLIVIP SLSVLTFLFT VGLLMYLRQC SGPKETKAHS
   721  SG

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against ADAM21 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
1
Mean surface accessibility (rSASA)
0.3
Highest tissue expression
8.1 nTPM

Expression across tissuesHPA

Tissue

  • testis: 8.1 nTPM
  • retina: 1.2 nTPM
  • adrenal gland: 0.4 nTPM
  • cerebellum: 0.4 nTPM
  • cerebral cortex: 0.3 nTPM
  • basal ganglia: 0.2 nTPM

Single-cell type

  • late spermatids: 225 nCPM
  • early spermatids: 96 nCPM
  • adipocytes: 56 nCPM
  • late primary spermatocytes: 53 nCPM
  • cardiomyocytes: 35 nCPM
  • myonuclei: 33 nCPM

Immune cell

  • naive CD8 T-cell: 0.2 nTPM
  • memory B-cell: 0.1 nTPM
  • naive CD4 T-cell: 0.1 nTPM
  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM

Brain region

  • cerebral cortex: 5.8 nTPM
  • basal ganglia: 4.6 nTPM
  • hippocampal formation: 4.6 nTPM
  • white matter: 4.6 nTPM
  • amygdala: 4.4 nTPM
  • choroid plexus: 4.1 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)
1.43
gnomAD pLI
0
gnomAD missense Z
0.31
DepMap mean gene effect
-0.06
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

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads ADAM21 as an antibody target. Whether an autoantibody or antibody against ADAM21 could matter depends on whether native ADAM21 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

ADAM21 is annotated at the cell surface, where native ADAM21 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 ADAM21 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/ADAM21. 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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