Gene/Proteome Database (LMPD)
LMPD ID
LMP006028
Gene ID
Species
Homo sapiens (Human)
Gene Name
STT3B, subunit of the oligosaccharyltransferase complex (catalytic)
Gene Symbol
Synonyms
CDG1X; SIMP; STT3-B
Alternate Names
dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit STT3B; homolog of yeast STT3; oligosaccharyl transferase subunit STT3B; source of immunodominant MHC-associated peptides homolog; dolichyl-diphosphooligosaccharide protein glycotransferase; STT3, subunit of the oligosaccharyltransferase complex, homolog B
Chromosome
3
Map Location
3p23
EC Number
2.4.99.18
Summary
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). [provided by RefSeq, Jun 2014]
Orthologs
Proteins
| dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit STT3B | |
|---|---|
| Refseq ID | NP_849193 |
| Protein GI | 30578410 |
| UniProt ID | Q8TCJ2 |
| mRNA ID | NM_178862 |
| Length | 826 |
| RefSeq Status | REVIEWED |
| MAEPSAPESKHKSSLNSSPWSGLMALGNSRHGHHGPGAQCAHKAAGGAAPPKPAPAGLSGGLSQPAGWQSLLSFTILFLAWLAGFSSRLFAVIRFESIIHEFDPWFNYRSTHHLASHGFYEFLNWFDERAWYPLGRIVGGTVYPGLMITAGLIHWILNTLNITVHIRDVCVFLAPTFSGLTSISTFLLTRELWNQGAGLLAACFIAIVPGYISRSVAGSFDNEGIAIFALQFTYYLWVKSVKTGSVFWTMCCCLSYFYMVSAWGGYVFIINLIPLHVFVLLLMQRYSKRVYIAYSTFYIVGLILSMQIPFVGFQPIRTSEHMAAAGVFALLQAYAFLQYLRDRLTKQEFQTLFFLGVSLAAGAVFLSVIYLTYTGYIAPWSGRFYSLWDTGYAKIHIPIIASVSEHQPTTWVSFFFDLHILVCTFPAGLWFCIKNINDERVFVALYAISAVYFAGVMVRLMLTLTPVVCMLSAIAFSNVFEHYLGDDMKRENPPVEDSSDEDDKRNQGNLYDKAGKVRKHATEQEKTEEGLGPNIKSIVTMLMLMLLMMFAVHCTWVTSNAYSSPSVVLASYNHDGTRNILDDFREAYFWLRQNTDEHARVMSWWDYGYQIAGMANRTTLVDNNTWNNSHIALVGKAMSSNETAAYKIMRTLDVDYVLVIFGGVIGYSGDDINKFLWMVRIAEGEHPKDIRESDYFTPQGEFRVDKAGSPTLLNCLMYKMSYYRFGEMQLDFRTPPGFDRTRNAEIGNKDIKFKHLEEAFTSEHWLVRIYKVKAPDNRETLDHKPRVTNIFPKQKYLSKKTTKRKRGYIKNKLVFKKGKKISKKTV | |
Gene Information
Entrez Gene ID
Gene Name
STT3B, subunit of the oligosaccharyltransferase complex (catalytic)
Gene Symbol
Species
Homo sapiens
Gene Ontology (GO Annotations)
| GO ID | Source | Type | Description |
|---|---|---|---|
| GO:0016021 | IEA:UniProtKB-KW | C | integral component of membrane |
| GO:0016020 | IDA:UniProtKB | C | membrane |
| GO:0008250 | ISS:UniProtKB | C | oligosaccharyltransferase complex |
| GO:0004579 | IMP:UniProtKB | F | dolichyl-diphosphooligosaccharide-protein glycotransferase activity |
| GO:0030433 | IMP:UniProtKB | P | ER-associated ubiquitin-dependent protein catabolic process |
| GO:0043686 | IMP:UniProtKB | P | co-translational protein modification |
| GO:0006516 | IMP:UniProtKB | P | glycoprotein catabolic process |
| GO:0043687 | IMP:UniProtKB | P | post-translational protein modification |
| GO:0018279 | IMP:UniProtKB | P | protein N-linked glycosylation via asparagine |
| GO:0006986 | IMP:UniProtKB | P | response to unfolded protein |
KEGG Pathway Links
Domain Information
InterPro Annotations
| Accession | Description |
|---|---|
| IPR003674 | Oligosaccharyl transferase, STT3 subunit |
UniProt Annotations
Entry Information
Gene Name
STT3B, subunit of the oligosaccharyltransferase complex (catalytic)
Protein Entry
STT3B_HUMAN
UniProt ID
Species
Human
Comments
| Comment Type | Description |
|---|---|
| Catalytic Activity | Dolichyl diphosphooligosaccharide + [protein]- L-asparagine = dolichyl diphosphate + a glycoprotein with the oligosaccharide chain attached by N-beta-D-glycosyl linkage to a protein L-asparagine. |
| Disease | Congenital disorder of glycosylation 1X (CDG1X) [MIM |
| 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). 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 cotranslational 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. |
| Pathway | Protein modification; protein glycosylation. |
| Sequence Caution | Sequence=AAH15880.1; Type=Erroneous initiation; Note=Translation N-terminally extended.; Evidence= ; Sequence=BAB55370.1; Type=Erroneous initiation; Note=Translation N-terminally extended.; Evidence= ; Sequence=BAC11581.1; Type=Erroneous initiation; Note=Translation N-terminally extended.; Evidence= ; |
| Similarity | Belongs to the STT3 family. |
| Subcellular Location | Endoplasmic reticulum membrane; Multi-pass membrane protein. |
| Subunit | Component of the oligosaccharyltransferase (OST) complex (By similarity). OST seems to exist in different forms which contain at least RPN1, RPN2, OST48, DAD1, OSTC, KRTCAP2 and either STT3A or STT3B. OST can form stable complexes with the Sec61 complex or with both the Sec61 and TRAP complexes. {ECO |
| Tissue Specificity | Expressed in heart, brain, placenta, lung, liver, muscle, kidney and pancreas. Expressed in skin fibroblasts (at protein level). |
Identical and Related Proteins
Unique RefSeq proteins for LMP006028 (as displayed in Record Overview)
| Protein GI | Database | Accession | Length | Protein Name |
|---|---|---|---|---|
| 30578410 | RefSeq | NP_849193 | 826 | dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit STT3B |
Identical Sequences to LMP006028 proteins
| Reference | Database | Accession | Length | Protein Name |
|---|---|---|---|---|
| GI:30578410 | GenBank | AEI19169.1 | 826 | Sequence 498 from patent US 7960100 |
| GI:30578410 | GenBank | AEI19170.1 | 826 | Sequence 499 from patent US 7960100 |
| GI:30578410 | GenBank | AFL25713.1 | 826 | Sequence 62 from patent US 8168586 |
| GI:30578410 | GenBank | JAA26515.1 | 826 | STT3, subunit of the oligosaccharyltransferase complex, homolog B [Pan troglodytes] |
| GI:30578410 | GenBank | JAA36880.1 | 826 | STT3, subunit of the oligosaccharyltransferase complex, homolog B [Pan troglodytes] |
| GI:30578410 | GenBank | AGV81740.1 | 826 | Sequence 62 from patent US 8524238 |
Related Sequences to LMP006028 proteins
| Reference | Database | Accession | Length | Protein Name |
|---|---|---|---|---|
| GI:30578410 | GenBank | JAB09768.1 | 826 | dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit STT3B [Callithrix jacchus] |
| GI:30578410 | GenBank | JAB14206.1 | 826 | dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit STT3B [Callithrix jacchus] |
| GI:30578410 | RefSeq | XP_002814021.1 | 826 | PREDICTED: dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit STT3B isoform X1 [Pongo abelii] |
| GI:30578410 | RefSeq | XP_004676415.1 | 826 | PREDICTED: dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit STT3B [Condylura cristata] |
| GI:30578410 | RefSeq | XP_004786857.1 | 826 | PREDICTED: dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit STT3B [Mustela putorius furo] |
| GI:30578410 | RefSeq | XP_008982204.1 | 826 | PREDICTED: dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit STT3B [Callithrix jacchus] |