Protein: Dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit STT3 (Oligosaccharyl transferase subunit STT3) (EC 2.4.99.18) (Staurosporine and temperature sensitivity protein 3) (P39007)
Organism: Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast)
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.
Subcellular location: Endoplasmic reticulum membrane {ECO:0000269|PubMed:14562095}; Multi-pass membrane protein {ECO:0000269|PubMed:29301962}.
Sequence: MGSDRSCVLSVFQTILKLVIFVAIFGAAISSRLFAVIKFESIIHEFDPWFNYRATKYLVNNSFYKFLNWFDDRTWYPLGRVTGGTLYPGLMTTSAFIWHALRNWLGLPIDIRNVCVLFAPLFSGVTAWATYEFTKEIKDASAGLLAAGFIAIVPGYISRSVAGSYDNEAIAITLLMVTFMFWIKAQKTGSIMHATCAALFYFYMVSAWGGYVFITNLIPLHVFLLILMGRYSSKLYSAYTTWYAIGTVASMQIPFVGFLPIRSNDHMAALGVFGLIQIVAFGDFVKGQISTAKFKVIMMVSLFLILVLGVVGLSALTYMGLIAPWTGRFYSLWDTNYAKIHIPIIASVSEHQPVSWPAFFFDTHFLIWLFPAGVFLLFLDLKDEHVFVIAYSVLCSYFAGVMVRLMLTLTPVICVSAAVALSKIFDIYLDFKTSDRKYAIKPAALLAKLIVSGSFIFYLYLFVFHSTWVTRTAYSSPSVVLPSQTPDGKLALIDDFREAYYWLRMNSDEDSKVAAWWDYGYQIGGMADRTTLVDNNTWNNTHIAIVGKAMASPEEKSYEILKEHDVDYVLVIFGGLIGFGGDDINKFLWMIRISEGIWPEEIKERDFYTAEGEYRVDARASETMRNSLLYKMSYKDFPQLFNGGQATDRVRQQMITPLDVPPLDYFDEVFTSENWMVRIYQLKKDDAQGRTLRDVGELTRSSTKTRRSIKRPELGLRV
InterPro domains: - IPR048307: Oligosaccharyl transferase STT3, N-terminal domain (domain) [15-417]
- IPR048999: STT3/PglB/AglB, core domain (domain) [511-562]
- IPR003674: Oligosaccharyl transferase, STT3 subunit (family) [10-693]
Interaction partners: - Dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit OST6
- Dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit OST4
- Dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit OST5
- Dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit SWP1
- Dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit WBP1
- Dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit 1
- Protein transport protein SEC61
- Dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit 3
- Dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit OST2
- Protein transport protein SBH2
Gene Ontology annotations:
Molecular Function (MF): GO:0003674 (molecular function), GO:0003824 (catalytic activity), GO:0016740 (transferase activity), GO:0016757 (glycosyltransferase activity), GO:0016758 (hexosyltransferase activity)
Biological Process (BP): GO:0008150 (biological process), GO:0008152 (metabolic process), GO:0009987 (cellular process), GO:0009058 (biosynthetic process), GO:0044237 (cellular metabolic process), GO:0006807 (nitrogen compound metabolic process), GO:0070085 (glycosylation), GO:0071704 (organic substance metabolic process), GO:0044238 (primary metabolic process), GO:1901564 (organonitrogen compound metabolic process), GO:1901576 (organic substance biosynthetic process), GO:0019538 (protein metabolic process), GO:0044249 (cellular biosynthetic process), GO:0044260 (cellular macromolecule metabolic process), GO:0043170 (macromolecule metabolic process), GO:0043413 (macromolecule glycosylation), GO:1901135 (carbohydrate derivative metabolic process), GO:0036211 (protein modification process), GO:1901566 (organonitrogen compound biosynthetic process), GO:0009059 (macromolecule biosynthetic process), GO:0006486 (protein glycosylation), GO:0043412 (macromolecule modification), GO:0009100 (glycoprotein metabolic process), GO:0034645 (cellular macromolecule biosynthetic process), GO:1901137 (carbohydrate derivative biosynthetic process), GO:0006487 (protein N-linked glycosylation), GO:0009101 (glycoprotein biosynthetic process)
Cellular Component (CC): GO:0005575 (cellular component), GO:0032991 (protein-containing complex), GO:0110165 (cellular anatomical entity), GO:0005622 (intracellular anatomical structure), GO:0043226 (organelle), GO:0140534 (endoplasmic reticulum protein-containing complex), GO:0016020 (membrane), GO:0098796 (membrane protein complex), GO:0031984 (organelle subcompartment), GO:1902494 (catalytic complex), GO:0005737 (cytoplasm), GO:0012505 (endomembrane system), GO:0031090 (organelle membrane), GO:1990234 (transferase complex), GO:0043229 (intracellular organelle), GO:0098827 (endoplasmic reticulum subcompartment), GO:0042175 (nuclear outer membrane-endoplasmic reticulum membrane network), GO:0005783 (endoplasmic reticulum), GO:0008250 (oligosaccharyltransferase complex), GO:0043227 (membrane-bounded organelle), GO:0043231 (intracellular membrane-bounded organelle), GO:0005789 (endoplasmic reticulum membrane)