MGAT5
Description
The MGAT5 (alpha-1,6-mannosylglycoprotein 6-beta-N-acetylglucosaminyltransferase) is a protein-coding gene located on chromosome 2.
MGAT5 (Alpha-1,6-mannosylglycoprotein 6-beta-N-acetylglucosaminyltransferase A) is an enzyme involved in the synthesis of protein-bound and lipid-bound oligosaccharides. It adds N-acetylglucosamine (GlcNAc) to the alpha-linked mannose of biantennary N-linked oligosaccharides, which are found on cell surface glycoproteins. Alterations in these oligosaccharides can significantly change cell behavior, including adhesion and migration. Increased activity of MGAT5 may be linked to the progression of invasive malignancies.
MGAT5 catalyzes the addition of N-acetylglucosamine (GlcNAc) to the alpha-linked mannose of biantennary N-linked oligosaccharides, a crucial step in the biosynthesis of complex N-glycans. These complex N-glycans are found on proteins like EGFR, TGFR (TGF-beta receptor), and CDH2. MGAT5's role in N-glycan synthesis is critical for activating cellular signaling pathways, reorganizing the actin cytoskeleton, regulating cell-cell adhesion, and promoting cell migration. MGAT5-dependent EGFR glycosylation enhances the interaction between EGFR and LGALS3, preventing rapid EGFR endocytosis and extending EGFR signaling. MGAT5 is essential for efficient interaction between TGFB1 and its receptor. It amplifies the activation of intracellular signaling pathways by growth factors like FGF2, PDGF, IGF, TGFB1, and EGF. MGAT5-dependent CDH2 glycosylation inhibits CDH2-mediated cell-cell adhesion, influencing downstream signaling pathways. MGAT5 promotes cell migration and contributes to the regulation of the inflammatory response. MGAT5-dependent TCR glycosylation enhances the interaction between TCR and LGALS3, limiting TCR clustering and dampening TCR-mediated responses to antigens. MGAT5 is crucial for normal leukocyte evasation and accumulation at inflammation sites, inhibiting monocyte attachment to the vascular endothelium and subsequent monocyte diapedesis. It promotes umbilical vein endothelial cell proliferation and angiogenesis, partly by promoting FGF2 release from the extracellular matrix.
MGAT5 is also known as GNT-V, GNT-VA, MGAT5A, glcNAc-T V.
