Rabbit anti-Human STT3B Polyclonal Antibody

Uniprot Id

Q8TCJ2

Target Species

Human

Target Name

STT3B

Target Full Name

Dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit STT3B

Target Function

Catalytic subunit of the oligosaccharyl transferase (OST) complex that catalyzes the initial transfer of a defined glycan (Glc(3)Man(9)GlcNAc(2) in eukaryotes) from the lipid carrier dolichol-pyrophosphate to an asparagine residue within an Asn-X-Ser/Thr consensus motif in nascent polypeptide chains, the first step in protein N-glycosylation. 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). All subunits are required for a maximal enzyme activity. This subunit contains the active site and the acceptor peptide and donor lipid-linked oligosaccharide (LLO) binding pockets. STT3B is present in a small subset of OST complexes and mediates both cotranslational and post-translational N-glycosylation of target proteins: STT3B-containing complexes are required for efficient post-translational glycosylation and while they are less competent than STT3A-containing complexes for cotranslational glycosylation, they have the ability to mediate glycosylation of some nascent sites that are not accessible for STT3A. STT3B-containing complexes also act post-translationally and mediate modification of skipped glycosylation sites in unfolded proteins. Plays a role in ER-associated degradation (ERAD) pathway that mediates ubiquitin-dependent degradation of misfolded endoplasmic reticulum proteins by mediating N-glycosylation of unfolded proteins, which are then recognized by the ERAD pathway and targeted for degradation. Mediates glycosylation of the disease variant AMYL-TTR 'Asp-38' of TTR at 'Asn-118', leading to its degradation.

Target Involvement

Congenital disorder of glycosylation 1X (CDG1X)

Target Subcellular Location

Endoplasmic reticulum. Endoplasmic reticulum membrane; Multi-pass membrane protein.

Target Protein Families

STT3 family

Target Tissue Specificity

Expressed in heart, brain, placenta, lung, liver, muscle, kidney and pancreas. Expressed in skin fibroblasts (at protein level).

Target Synonyms

Dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit STT3B; Homolog of yeast STT3; Oligosaccharyl transferase subunit STT3B; SIMP; source of immunodominant MHC associated peptides; Source of immunodominant MHC-associated peptides homolog; STT3 subunit of the oligosaccharyltransferase complex homolog B (S. cerevisiae); STT3 subunit of the oligosaccharyltransferase complex homolog B; STT3-B; Stt3b; STT3B_HUMAN

Target Background

The protein encoded by this gene is a catalytic subunit of a protein complex that transfers oligosaccharides onto asparagine residues. Defects in this gene are a cause of congenital disorder of glycosylation Ix (CDG1X).