N-acetylglucosamine-1-phosphate transferase
It is made up of two alpha (α), two betas (β), and two gammas (γ) subunits. "GNPTAB" produces the alpha and beta subunits, "GNPTG" produces the gamma subunit. GlcNAc-1-phosphotransferase functions to prepare newly made enzymes for lysosome transportation (lysosomal hydrolases to the lysosome). Lysosomes, a part of an animal cell, helps break down large molecules into smaller ones that can be reused. GlcNAc-1-phosphotransferase catalyzes the N-linked glycosylation of asparagine residues with a molecule called mannose-6-phosphate (M6P). M6P acts as an indicator of whether a hydrolase should be transported to the lysosome or not. Once a hydrolase indicates an M6P, it can be transported to a lysosome. Surprisingly some lysosomal enzymes are only tagged at a rate of 5% or lower. It is associated with the following conditions:


In melanocytic cells, GNPTG gene expression may be regulated by MITF.
Function
N-acetylglucosamine-1-phosphate transferase is a transferase enzyme.