Protein O-linked-mannose beta-1,2-N-acetylglucosaminyltransferase 1 (POMGNT1)

Protein O-linked-mannose beta-1,2-N-acetylglucosaminyltransferase 1 (POMGNT1) is a type II transmembrane glycosyltransferase enzyme encoded by the POMGNT1 gene on human chromosome 1p34.1. POMGNT1 catalyzes the addition of N-acetylglucosamine (GlcNAc) to O-mannose residues of glycoproteins, crucial for the synthesis and elongation of O-mannosyl glycans—especially on alpha-dystroglycan—in multiple tissues, including muscle, eye, and brain[1][2][3][5][7]. This posttranslational modification is vital for proper cell–matrix interactions and the formation of the extracellular matrix, particularly in neural tissue and muscle fibers[3][7]. Mutations in POMGNT1 lead to a spectrum of congenital muscular dystrophies known as dystroglycanopathies, most notably muscle-eye-brain disease (MEB) and limb-girdle muscular dystrophy type 2O (LGMD2O)[2][4][6]. Deficiency or dysfunction of POMGNT1 causes defective glycosylation of alpha-dystroglycan, leading to muscular, ocular, and cerebral pathology. Despite its crucial role in disease, no approved drugs target POMGNT1 directly for therapeutic use.

Other names

POMGnT1Protein O-mannose beta-1,2-N-acetylglucosaminyltransferase 1MGAT1.2FLJ20277LGMD2OLGMDR15Muscle-eye-brain disease protein (MEB protein)GNTI.2UDP-GlcNAc:alpha-D-mannoside beta-1,2-N-acetylglucosaminyltransferase I.2

(For theoretical or experimental inhibitors) Modulation of POMGNT1 would alter O-mannosyl glycan synthesis, affecting glycosylation of alpha-dystroglycan and downstream extracellular matrix function[1][5][7].