MGAT4C is a 478 amino acid single-pass type II membrane protein that localizes to the golgi apparatus and belongs to the glycosyltransferase 54 family. Expressed in liver, heart, testis, brain and adrenal gland, GnT-IVH functions as a glycosyltransferase that catalyzes the transfer of N-acetylglucosamine (GlcNAc) to the core mannose residues of N-linked glycans, thereby playing a crucial role in the production of tri- and tetra-antennary N-linked sugar chains. The gene encoding GnT-IVH maps to human chromosome 12, which encodes over 1,100 genes and comprises approximately 4.5% of the human genome.