InnateDB: Systems Biology of the Innate Immune Response

Homo sapiens Protein: STT3A

Summary

InnateDB Protein

IDBP-245108.5

Last Modified

2014-10-13 [Report errors or provide feedback]

Gene Symbol

STT3A

Protein Name

STT3, subunit of the oligosaccharyltransferase complex, homolog A (S. cerevisiae)

Synonyms

ITM1; STT3-A; TMC;

Species

Homo sapiens

Ensembl Protein

ENSP00000376472

InnateDB Gene

IDBG-75508 (STT3A)

Protein Structure

UniProt Annotation

Function

Catalytic subunit 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. N-glycosylation occurs cotranslationally and the complex associates with the Sec61 complex at the channel-forming translocon complex that mediates protein translocation across the endoplasmic reticulum (ER). SST3A seems to be involved in complex substrate specificity. STT3A is present in the majority of OST complexes and mediates cotranslational N-glycosylation of most sites on target proteins, while STT3B-containing complexes are required for efficient cotranslational glycosylation and mediate glycosylation of sites that have been skipped by STT3A. {ECO:0000269PubMed:19167329}.

Subcellular Localization

Endoplasmic reticulum membrane; Multi-pass membrane protein.

Disease Associations

Congenital disorder of glycosylation 1W (CDG1W) [MIM:615596]: 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. {ECO:0000269PubMed:23842455}. Note=The disease is caused by mutations affecting the gene represented in this entry.

Tissue Specificity

Expressed at high levels in placenta, liver, muscle and pancreas, and at very low levels in brain, lung and kidney. Expressed in skin fibroblasts (at protein level). {ECO:0000269PubMed:12887896}.

Comments

Interactions

Number of Interactions

This gene and/or its encoded proteins are associated with 26 experimentally validated interaction(s) in this database.

Experimentally validated
Total	26 [view]
Protein-Protein	24 [view]
Protein-DNA	1 [view]
Protein-RNA	1 [view]
DNA-DNA	0
RNA-RNA	0
DNA-RNA	0

Gene Ontology

Molecular Function

Accession	GO Term
GO:0004576	oligosaccharyl transferase activity
GO:0004579	dolichyl-diphosphooligosaccharide-protein glycotransferase activity
GO:0005515	protein binding

Biological Process

GO:0006486	protein glycosylation
GO:0018279	protein N-linked glycosylation via asparagine
GO:0043686	co-translational protein modification
GO:0043687	post-translational protein modification
GO:0044267	cellular protein metabolic process