Seroatlas · Human Serome Atlas

MASP2

Mannan-binding lectin serine protease 2

Also known as: MAP-2, Map19, MASP1P1, MASP2_HUMAN, sMAP

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

Protein identityUniProt · HPA

UniProt accession
O00187
Gene
MASP2
Ensembl
ENSG00000009724
Chromosome
1
Canonical length
686 aa
Protein class
Disease related genes, Enzymes, Human disease related genes, Plasma proteins, Potential drug targets, Predicted secreted proteins
Subcellular location
Golgi apparatus
Secretome location
Secreted to blood
Quaternary structure
Homodimer

OverviewNCBI Gene

This gene encodes a member of the peptidase S1 family of serine proteases. The encoded preproprotein is proteolytically processed to generate A and B chains that heterodimerize to form the mature protease. This protease cleaves complement components C2 and C4 in order to generate C3 convertase in the lectin pathway of the complement system. The encoded protease also plays a role in the coagulation cascade through cleavage of prothrombin to form thrombin. Myocardial infarction and acute stroke patients exhibit reduced serum concentrations of the encoded protein. Alternative splicing results in multiple transcript variants, at least one of which encodes an isoform that is proteolytically processed. [provided by RefSeq, Feb 2016]

Canonical amino-acid sequenceUniProt

686 residues, UniProt reviewed canonical sequence.

>O00187|MASP2
     1  MRLLTLLGLL CGSVATPLGP KWPEPVFGRL ASPGFPGEYA NDQERRWTLT APPGYRLRLY
    61  FTHFDLELSH LCEYDFVKLS SGAKVLATLC GQESTDTERA PGKDTFYSLG SSLDITFRSD
   121  YSNEKPFTGF EAFYAAEDID ECQVAPGEAP TCDHHCHNHL GGFYCSCRAG YVLHRNKRTC
   181  SALCSGQVFT QRSGELSSPE YPRPYPKLSS CTYSISLEEG FSVILDFVES FDVETHPETL
   241  CPYDFLKIQT DREEHGPFCG KTLPHRIETK SNTVTITFVT DESGDHTGWK IHYTSTAQPC
   301  PYPMAPPNGH VSPVQAKYIL KDSFSIFCET GYELLQGHLP LKSFTAVCQK DGSWDRPMPA
   361  CSIVDCGPPD DLPSGRVEYI TGPGVTTYKA VIQYSCEETF YTMKVNDGKY VCEADGFWTS
   421  SKGEKSLPVC EPVCGLSART TGGRIYGGQK AKPGDFPWQV LILGGTTAAG ALLYDNWVLT
   481  AAHAVYEQKH DASALDIRMG TLKRLSPHYT QAWSEAVFIH EGYTHDAGFD NDIALIKLNN
   541  KVVINSNITP ICLPRKEAES FMRTDDIGTA SGWGLTQRGF LARNLMYVDI PIVDHQKCTA
   601  AYEKPPYPRG SVTANMLCAG LESGGKDSCR GDSGGALVFL DSETERWFVG GIVSWGSMNC
   661  GEAGQYGVYT KVINYIPWIE NIISDF

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against MASP2 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)
0.29
Highest tissue expression
453 nTPM

Expression across tissuesHPA

Tissue

  • liver: 453 nTPM
  • cerebellum: 7.9 nTPM
  • bone marrow: 4.9 nTPM
  • retina: 4.2 nTPM
  • skin: 3.6 nTPM
  • skeletal muscle: 3.3 nTPM

Single-cell type

  • hepatocytes: 759 nCPM
  • cardiomyocytes: 257 nCPM
  • epicardial cells: 171 nCPM
  • myonuclei: 72 nCPM
  • adipocytes: 71 nCPM
  • fibro-adipogenic progenitors: 29 nCPM

Immune cell

  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM
  • MAIT T-cell: 0 nTPM

Brain region

  • cerebellum: 15 nTPM
  • cerebral cortex: 6.7 nTPM
  • white matter: 6 nTPM
  • basal ganglia: 5.4 nTPM
  • midbrain: 4.7 nTPM
  • hippocampal formation: 4.6 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about MASP2.

Disease | AllUniProt

Conditions MASP2 is implicated in, by any mechanism.

Disease | GeneticClinVar

3 pathogenic / likely-pathogenic of 212 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Immunodeficiency due to MASP-2 deficiency

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)
1.15
gnomAD pLI
0
gnomAD missense Z
0.06
DepMap mean gene effect
0.01
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 MASP2 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 MASP2 as an antibody target. Whether an autoantibody or antibody against MASP2 could matter depends on whether native MASP2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

MASP2 is annotated at the cell surface, where native MASP2 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 MASP2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/MASP2. 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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