FCN3

Calcium-dependent lectin, which acts as a pattern recognition receptor that initiates 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. Specifically recognizes and binds carbohydrates on the pathogen surface, activating the MASP1 serine protease and initiating the proteolytic cascade of the lectin complement pathway. Specifically binds N-Acetylglucosamine (GlcNAc,) GalNAc (N-acetylgalactosamine) and D-fucose on the surface of pathogens, as well as mono/oligosaccharide and lipopolysaccharides from S.typhimurium and S.minnesota..

Function from UniProtKB (O75636), read 2026-09-23. CC BY 4.0.