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Details on Person UniProt:O00187-1 MASP2

Class:IdReferenceIsoform:59007
_chainChangeLogsignal peptide:1-15 added on Fri February 6 2015;chain:16-686 added on Fri February 6 2015;chain:16-444 added on Fri February 6 2015;chain:445-686 added on Fri February 6 2015
_displayNameUniProt:O00187-1 MASP2
_timestamp2026-02-20 22:01:10
chainsignal peptide:1-15
chain:16-686
chain:16-444
chain:445-686
checksumED952085FA115E21
commentFUNCTION Precursor of a serum protease that activates the lectin pathway of the complement system, a cascade of proteins that leads to phagocytosis and breakdown of pathogens and signaling that strengthens the adaptive immune system (PubMed:11527969, PubMed:22691502). The lectin complement system is activated following association of lectins, such as MBL2, FCN1, FCN2 or FCN3, to carbohydrates on the pathogen surface (PubMed:22691502, PubMed:22966085). MASP2 is cleaved and activated by MASP1 in response to lectin-binding to pathogen carbohydrates (PubMed:10946292, PubMed:22949645, PubMed:22966085, PubMed:9087411). Can activate prothrombin to thrombin (PubMed:39924859).FUNCTION Serine protease component of the lectin complement pathway, which catalyzes cleavage and activation of C2 and C4, the next components of the complement pathway.CATALYTIC ACTIVITY Selective cleavage after Arg-223 in complement component C2 (-Ser-Leu-Gly-Arg-|-Lys-Ile-Gln-Ile) and after Arg-76 in complement component C4 (-Gly-Leu-Gln-Arg-|-Ala-Leu-Glu-Ile).ACTIVITY REGULATION The protease activity is specifically inhibited by SGMI-2 small protein inhibitor.ACTIVITY REGULATION (Microbial infection) Serine protease activity is inhibited by E.Coli ecotin (eco).SUBUNIT Homodimer; disulfide-linked (PubMed:15117939, PubMed:15364579). Interacts with MBL2 and FCN2; requires calcium ions (PubMed:15117939). Interacts with SERPING1 (PubMed:10946292). Interacts with guianensin, an anticoagulant and anti-complement protein from Simulium guianense saliva; the interaction results in the inhibition of MASP2 enzymatic activity (PubMed:39924859).INTERACTION Recruited to the surface of pathogens by the mannose-binding proteins, such as MBL2.ALTERNATIVE PRODUCTS Plasma.PTM Activated by cleavage after Arg-444 by MASP1. The uncleaved zymogen is inactive towards synthetic substrates, but has sufficient activity to effect autocatalytic cleavage.PTM The iron and 2-oxoglutarate dependent 3-hydroxylation of aspartate and asparagine is (R) stereospecific within EGF domains.DISEASE The disease is caused by variants affecting the gene represented in this entry.SIMILARITY Belongs to the peptidase S1 family.ONLINE INFORMATION MASP2 mutation db
descriptionrecommendedName: Mannan-binding lectin serine protease 2 ecNumber evidence="9 17 18 19 23"3.4.21.104 alternativeName: MBL-associated serine protease 2 alternativeName: fullName evidence="29"Mannose-binding protein-associated serine protease 2 shortName evidence="28 29"MASP-2 component recommendedName: Mannan-binding lectin serine protease 2 A chain /component component recommendedName: Mannan-binding lectin serine protease 2 B chain /component
geneNameMASP2
identifierO00187
isoformParent
isSequenceChangedFALSE
keyword3D-structure
Alternative splicing
Autocatalytic cleavage
Calcium
Complement pathway
Direct protein sequencing
Disease variant
Disulfide bond
EGF-like domain
Hydrolase
Hydroxylation
Immunity
Innate immunity
Metal-binding
Protease
Proteomics identification
Reference proteome
Repeat
Secreted
Serine protease
Signal
Sushi
modified[InstanceEdit:9836292] Weiser, Joel, 2023-05-25
[InstanceEdit:9852000] Weiser, Joel, 2023-11-03
[InstanceEdit:9926675] Weiser, Joel, 2024-11-03
[InstanceEdit:9983091] Weiser, Joel, 2026-02-20
nameMASP2
referenceDatabase[ReferenceDatabase:2] UniProt
referenceGene[ReferenceDNASequence:8996090] ENSEMBL:ENSG00000009724 MASP2 [Homo sapiens]
secondaryIdentifierMASP2_HUMAN
A8K458
A8MWJ2
O75754
Q5TEQ5
Q5TER0
Q96QG4
Q9BZH0
Q9H498
Q9H499
Q9UBP3
Q9UC48
Q9ULC7
Q9UMV3
Q9Y270
sequenceLength686
species[Species:48887] Homo sapiens
variantIdentifierO00187-1
(referenceEntity)[EntityWithAccessionedSequence:166689] MASP2-1 [extracellular region] [Homo sapiens]
[EntityWithAccessionedSequence:166703] MASP2-1(445-686) [extracellular region] [Homo sapiens]
[EntityWithAccessionedSequence:166705] MASP2-1(16-444) [extracellular region] [Homo sapiens]
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