FUT3
FUT3, or fucosyltransferase 3 (Lewis blood group), is a Golgi-resident enzyme also known as CD174 and LE. It transfers fucose to type 1 and type 2 chain acceptors and so builds the Lewis blood group antigens. Browse Assay Genie's current range of FUT3 research reagents below, or read on for the biology behind the target.
FUT3 catalyses the transfer of L-fucose from GDP-beta-L-fucose to acceptor glycans. On type 1 chain structures (beta-D-Gal-(1->3)-beta-D-GlcNAc) it forms an alpha(1,4) linkage to the subterminal N-acetylglucosamine, and on type 2 chain oligosaccharides (beta-D-Gal-(1->4)-beta-D-GlcNAc) it forms an alpha(1,3) linkage to the subterminal glucose or GlcNAc. It does this whether or not the terminal galactose carries an alpha-L-fucosyl-(1,2) group, and it prefers type 1 over type 2 acceptors. Through these reactions it takes part in the synthesis of Lewis a, Lewis b, Lewis x (SSEA-1) and Lewis y antigens.
The enzyme also fucosylates sialylated substrates. It converts sialyl- and disialyl-lactotetraosylceramide into sialyl Lewis a and disialyl Lewis a, and it can add fucose to 3'-sialyl-N-acetyllactosamine to form the sialyl Lewis x structure. In this way FUT3 may regulate cell surface sialyl Lewis a and sialyl Lewis x expression, and with it adhesion to E-selectin, cell proliferation and migration. The FUT3 gene product is a member of the glycosyltransferase 10 family and sits in the Golgi stack membrane.
The Lewis histo-blood group system consists of fucosylated glycosphingolipids made by exocrine epithelial cells, which circulate in body fluids and are secondarily absorbed onto red blood cells, giving the Lewis phenotype. These glycolipids are linked to embryogenesis, tissue differentiation, tumour metastasis, inflammation and bacterial adhesion. Lewis-positive individuals have an active enzyme, whereas Lewis-negative individuals have an inactive one, and mutations in this gene account for most Lewis antigen-negative phenotypes. Differences in FUT3 expression are also associated with host susceptibility to viral infection. The mouse ortholog is Sec1.
FUT3 carries out the last step of Lewis antigen biosynthesis, and its activity determines whether an individual is Lewis-positive or Lewis-negative.
The enzyme forms both alpha(1,3) and alpha(1,4) fucose linkages, making it a useful model for acceptor preference among fucosyltransferases.
By shaping sialyl Lewis a and sialyl Lewis x expression, FUT3 may influence E-selectin adhesion, proliferation and migration relevant to tumour metastasis.
Lewis glycolipids are involved in bacterial adhesion, and differences in FUT3 expression are associated with host susceptibility to viral infection.
FUT3 is a fucosyltransferase that transfers L-fucose from GDP-fucose to type 1 and type 2 chain acceptors. It synthesises Lewis a, Lewis b, Lewis x and Lewis y antigens, and also sialyl Lewis a and sialyl Lewis x structures, which may affect E-selectin binding.
The HGNC name is fucosyltransferase 3 (Lewis blood group); the UniProt name is 3-galactosyl-N-acetylglucosaminide 4-alpha-L-fucosyltransferase FUT3. Aliases include CD174 and LE. The older name was fucosyltransferase 3 (galactoside 3(4)-L-fucosyltransferase, Lewis blood group included). Its EC number is 2.4.1.65.
Lewis-positive individuals have an active FUT3 enzyme, while Lewis-negative individuals have an inactive one. Mutations in the gene are responsible for most Lewis antigen-negative phenotypes. The mouse ortholog is Sec1; check the datasheet of any product for its validated reactivity.
Other fucosyltransferases and glycosylation enzymes involved in fucosylated glycan synthesis.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P21217; product specifications from Assay Genie datasheets.