Map44

mannan-binding lectin serine peptidase 1 (C4/C2 activating component of Ra-reactive factor)
Identifiers
Symbol	MASP1
Alt. symbols	CRARF, PRSS5
Entrez	5648
HUGO	6901
OMIM	600521
RefSeq	NM_001879
UniProt	P48740
Other data
Locus	Chr. 3 q27-q28

Mannose-binding lectin-associated protein of 44 kDa (MAp44) is a protein arising from the human MASP1 gene. MASP-1, MASP-3 and MAp44 are alternative splice products of the MASP1 gene. MAp44 has been suggested to act as a competitive inhibitor of lectin pathway activation, by displacing MASP-2 from MBL, hence preventing cleavage of C4 and C2

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