FCN3
Description
The FCN3 (ficolin 3) is a protein-coding gene located on chromosome 1.
FCN3 is a protein encoded by the FCN3 gene in humans. It was initially identified as H-ficolin (H for Hakata antigen), an autoantigen found in patients from Hakata. Ficolins are proteins with a collagen-like and a fibrinogen-like domain. Human serum contains two types of ficolins with lectin activity. FCN3, also known as a thermolabile beta-2-macroglycoprotein, is found in all human serum and is part of the ficolin/opsonin p35 lectin family. It was initially identified due to its reactivity with sera from patients with systemic lupus erythematosus and was shown to have calcium-independent lectin activity. FCN3 activates the complement pathway in association with MASPs and sMAP, aiding in host defense through the lectin pathway. Alternative splicing generates two variants, each encoding a distinct isoform.
FCN3 plays a role in innate immunity by activating the lectin complement pathway. It binds to GlcNAc in a calcium-dependent manner and interacts with GalNAc, GlcNAc, and D-fucose, as well as lipopolysaccharides from S.typhimurium and S.minnesota.
FCN3 is also known as FCNH, HAKA1.