Fig. 2.

Schematic diagram of the gene and protein structure of O-GlcNAc modifying enzymes. Human OGT is composed of three regions and three splice forms are known. An N-terminal domain is formed from a series of TPRs and a C-terminal domain contains the glycosyltransferase catalytic domain. A Schematic of the genomic structure of the human OGT splice variants. B The linear domain organization is shown for the three OGT isoforms with the amino acids marking the boundary of each domain indicated. The TPRs are shown in light gray, the nuclear localization sequence (NLS) is in yellow, and the glycosyltransferase catalytic regions are in light blue (Cat-1and Cat-2). C The linear domain organization is shown for the two OGA isoforms with the amino acids marking the boundary of each domain indicated. The Catalytic GH84 is shown in orange, the pseudo-HAT is shown in yellow