MAGT1
Function
Accessory component of the STT3B-containing form of the N-oligosaccharyl transferase (OST) complex which catalyzes the transfer of a high mannose oligosaccharide from a lipid-linked oligosaccharide donor to an asparagine residue within an Asn-X-Ser/Thr consensus motif in nascent polypeptide chains (PubMed:31831667). Involved in N-glycosylation of STT3B-dependent substrates (PubMed:31831667). Specifically required for the glycosylation of a subset of acceptor sites that are near cysteine residues; in this function seems to act redundantly with TUSC3. In its oxidized form proposed to form transient mixed disulfides with a glycoprotein substrate to facilitate access of STT3B to the unmodified acceptor site. Has also oxidoreductase-independent functions in the STT3B-containing OST complex possibly involving substrate recognition. Could indirectly play a role in Mg(2+) transport in epithelial cells (Probable).
Involvement in disease
Immunodeficiency, X-linked, with magnesium defect, Epstein-Barr virus infection and neoplasia
XMEN
A disease characterized by CD4 lymphopenia, severe chronic viral infections, and defective T-lymphocyte activation.
None
The disease is caused by variants affecting the gene represented in this entry.
Congenital disorder of glycosylation 1CC
CDG1CC
A form of congenital disorder of glycosylation, a multisystem disorder caused by a defect in glycoprotein biosynthesis and characterized by under-glycosylated serum glycoproteins. Congenital disorders of glycosylation result in a wide variety of clinical features, such as defects in the nervous system development, psychomotor retardation, dysmorphic features, hypotonia, coagulation disorders, and immunodeficiency. The broad spectrum of features reflects the critical role of N-glycoproteins during embryonic development, differentiation, and maintenance of cell functions. CDG1CC is an X-linked recessive form mainly characterized by intellectual and developmental disability.
None
The disease is caused by variants affecting the gene represented in this entry.
Pathway
Protein modification; protein glycosylation.
Sequence Similarities
Belongs to the OST3/OST6 family.
Tissue Specificity
Ubiquitous. Expressed at very low levels in brain, lung and kidney.
Cellular localization
- Cell membrane
- Multi-pass membrane protein
- Endoplasmic reticulum
- Endoplasmic reticulum membrane
- Multi-pass membrane protein
Alternative names
IAG2, PSEC0084, UNQ628/PRO1244, MAGT1, Dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit MAGT1, Oligosaccharyl transferase subunit MAGT1, Implantation-associated protein, Magnesium transporter protein 1, IAP, MagT1