POMGNT1

The protein encoded by this gene is a type II transmembrane protein that resides in the golgi. It participates in O-mannosyl glycosylation, and is specific for alpha linked terminal mannose. Mutations in this gene are associated with muscle-eye-brain (MEB) disease. Alternatively spliced transcript variants have been found for this gene

Full Name

protein O-linked mannose beta1,2-N-acetylglucosaminyltransferase

Function

Participates in O-mannosyl glycosylation by catalyzing the addition of N-acetylglucosamine to O-linked mannose on glycoproteins (PubMed:11709191, PubMed:27493216, PubMed:28512129).
Catalyzes the synthesis of the GlcNAc(beta1-2)Man(alpha1-)O-Ser/Thr moiety on alpha-dystroglycan and other O-mannosylated proteins, providing the necessary basis for the addition of further carbohydrate moieties (PubMed:11709191, PubMed:27493216).
Is specific for alpha linked terminal mannose and does not have MGAT3, MGAT4, MGAT5, MGAT7 or MGAT8 activity.

Biological Process

O-glycan processingManual Assertion Based On ExperimentIDA:UniProtKB
Protein O-linked glycosylationManual Assertion Based On ExperimentIDA:MGI

Cellular Location

Golgi apparatus membrane

Involvement in disease

Muscular dystrophy-dystroglycanopathy congenital with brain and eye anomalies A3 (MDDGA3):
An autosomal recessive disorder characterized by congenital muscular dystrophy, ocular abnormalities, cobblestone lissencephaly, and cerebellar and pontine hypoplasia. Patients present severe congenital myopia, congenital glaucoma, pallor of the optic disks, retinal hypoplasia, intellectual disability, hydrocephalus, abnormal electroencephalograms, generalized muscle weakness and myoclonic jerks. Included diseases are the more severe Walker-Warburg syndrome and the slightly less severe muscle-eye-brain disease.
Muscular dystrophy-dystroglycanopathy congenital with impaired intellectual development B3 (MDDGB3):
An autosomal recessive disorder characterized by congenital muscular dystrophy associated with intellectual disability and mild structural brain abnormalities. Clinical features include intellectual disability, white matter changes, cerebellar cysts, pontine hypoplasia, myopia, optic atrophy, decreased alpha-dystroglycan on muscle biopsy and increased serum creatine kinase.
Muscular dystrophy-dystroglycanopathy limb-girdle C3 (MDDGC3):
A rare form of limb-girdle muscular dystrophy with normal cognition. Muscle biopsy shows dystrophic changes with variable staining for glycosylated alpha-dystroglycan.
Retinitis pigmentosa 76 (RP76):
A form of retinitis pigmentosa, a retinal dystrophy belonging to the group of pigmentary retinopathies. Retinitis pigmentosa is characterized by retinal pigment deposits visible on fundus examination and primary loss of rod photoreceptor cells followed by secondary loss of cone photoreceptors. Patients typically have night vision blindness and loss of midperipheral visual field. As their condition progresses, they lose their far peripheral visual field and eventually central vision as well. RP76 inheritance is autosomal recessive.

Topology

Cytoplasmic: 1-37
Helical: 38-58
Lumenal: 59-660