Seroatlas · Human Serome Atlas

MMP21

Matrix metalloproteinase-21

Also known as: MMP21_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q8N119
Gene
MMP21
Ensembl
ENSG00000154485
Chromosome
10
Canonical length
569 aa
Protein class
Disease related genes, Enzymes, Human disease related genes, Potential drug targets, Predicted intracellular proteins, Predicted secreted proteins
Secretome location
Secreted to extracellular matrix

OverviewNCBI Gene

This gene encodes a member of the matrix metalloproteinase family. Proteins in this family are involved in the breakdown of extracellular matrix for both normal physiological processes, such as embryonic development, reproduction, and tissue remodeling, and disease processes, such as asthma and tumor metastasis. The encoded protein may play an important role in embryogenesis, particularly in neuronal cells, as well as in lymphocyte development and survival. [provided by RefSeq, May 2013]

Canonical amino-acid sequenceUniProt

569 residues, UniProt reviewed canonical sequence.

>Q8N119|MMP21
     1  MLAASIFRPT LLLCWLAAPW PTQPESLFHS RDRSDLEPSP LRQAKPIADL HAAQRFLSRY
    61  GWSGVWAAWG PSPEGPPETP KGAALAEAVR RFQRANALPA SGELDAATLA AMNRPRCGVP
   121  DMRPPPPSAP PSPPGPPPRA RSRRSPRAPL SLSRRGWQPR GYPDGGAAQA FSKRTLSWRL
   181  LGEALSSQLS VADQRRIVAL AFRMWSEVTP LDFREDLAAP GAAVDIKLGF GRGRHLGCPR
   241  AFDGSGQEFA HAWRLGDIHF DDDEHFTPPT SDTGISLLKV AVHEIGHVLG LPHTYRTGSI
   301  MQPNYIPQEP AFELDWSDRK AIQKLYGSCE GSFDTAFDWI RKERNQYGEV MVRFSTYFFR
   361  NSWYWLYENR NNRTRYGDPI QILTGWPGIP THNIDAFVHI WTWKRDERYF FQGNQYWRYD
   421  SDKDQALTED EQGKSYPKLI SEGFPGIPSP LDTAFYDRRQ KLIYFFKESL VFAFDVNRNR
   481  VLNSYPKRIT EVFPAVIPQN HPFRNIDSAY YSYAYNSIFF FKGNAYWKVV NDKDKQQNSW
   541  LPANGLFPKK FISEKWFDVC DVHISTLNM

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against MMP21 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
Secreted
Secreted
Yes
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.31
Highest tissue expression
51 nTPM

Expression across tissuesHPA

Tissue

  • epididymis: 51 nTPM
  • ovary: 3.2 nTPM
  • pancreas: 1.6 nTPM
  • retina: 1.6 nTPM
  • salivary gland: 1.5 nTPM
  • cerebellum: 1.2 nTPM

Single-cell type

  • epididymal principal cells: 33 nCPM
  • cardiomyocytes: 31 nCPM
  • epicardial cells: 30 nCPM
  • late spermatids: 27 nCPM
  • adipocytes: 18 nCPM
  • fibro-adipogenic progenitors: 14 nCPM

Immune cell

  • gdT-cell: 0.1 nTPM
  • naive B-cell: 0.1 nTPM
  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • intermediate monocyte: 0 nTPM

Brain region

  • cerebellum: 6 nTPM
  • white matter: 4.2 nTPM
  • cerebral cortex: 4 nTPM
  • basal ganglia: 3.9 nTPM
  • hypothalamus: 3.7 nTPM
  • hippocampal formation: 3.5 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about MMP21.

Disease | AllUniProt

Conditions MMP21 is implicated in, by any mechanism.

  • Heterotaxy, visceral, 7, autosomal (HTX7) MIM:616749

Disease | GeneticClinVar

24 pathogenic / likely-pathogenic of 177 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)
1.2
gnomAD pLI
0
gnomAD missense Z
1.34
DepMap mean gene effect
-0.03
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 MMP21 as an antibody target. Whether an autoantibody or antibody against MMP21 could matter depends on whether native MMP21 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

MMP21 is annotated as secreted, so native MMP21 circulates and is directly accessible to antibodies. Secreted and cell-surface proteins are the autoantibody targets most likely to act like drugs, blocking or depleting the native protein.

Annotation status

The present source text does not explicitly label MMP21 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/MMP21. 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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