Dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit 1 (RPN1)
The protein contains 607 amino acids for an estimated molecular weight of 68569 Da.
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. (updated: Dec. 5, 2018)
Protein identification was indicated in the following studies:
- Hegedűs and co-workers. (2015) Inconsistencies in the red blood cell membrane proteome analysis: generation of a database for research and diagnostic applications. Database (Oxford) 1-8.
- Wilson and co-workers. (2016) Comparison of the Proteome of Adult and Cord Erythroid Cells, and Changes in the Proteome Following Reticulocyte Maturation. Mol Cell Proteomics. 15(6), 1938-1946.
- Bryk and co-workers. (2017) Quantitative Analysis of Human Red Blood Cell Proteome. J Proteome Res. 16(8), 2752-2761.
- D'Alessandro and co-workers. (2017) Red blood cell proteomics update: is there more to discover? Blood Transfus. 15(2), 182-187.
- Chu and co-workers. (2018) Quantitative mass spectrometry of human reticulocytes reveal proteome-wide modifications during maturation. Br J Haematol. 180(1), 118-133.
Methods
The following articles were analysed to gather the proteome content of erythrocytes.
The gene or protein list provided in the studies were processed using the ID mapping API of Uniprot in September 2018. The number of proteins identified and mapped without ambiguity in these studies is indicated below.
Only Swiss-Prot entries (reviewed) were considered for protein evidence assignation.
| Publication | Identification 1 | Uniprot mapping 2 | Not mapped / Obsolete | TrEMBL | Swiss-Prot |
|---|---|---|---|---|---|
| Goodman (2013) | 2289 (gene list) | 2278 | 53 | 20599 | 2269 |
| Lange (2014) | 1234 | 1234 | 7 | 28 | 1224 |
| Hegedus (2015) | 2638 | 2622 | 0 | 235 | 2387 |
| Wilson (2016) | 1658 | 1528 | 170 | 291 | 1068 |
| d'Alessandro (2017) | 1826 | 1817 | 2 | 0 | 1815 |
| Bryk (2017) | 2090 | 2060 | 10 | 108 | 1942 |
| Chu (2018) | 1853 | 1804 | 55 | 362 | 1387 |
1 as available in the article and/or in supplementary material
2 uniprot mapping returns all protein isoforms as one entry
The compilation of older studies can be retrieved from the Red Blood Cell Collection database.
The data and differentiation stages presented below come from the proteomic study and analysis performed by our partners of the GReX consortium, more details are available in their published work.
This protein is predicted to be membranous by TOPCONS.
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Biological Process
Cellular protein modification process
Protein N-linked glycosylation
Protein N-linked glycosylation via asparagine
Viral protein processing
The reference OMIM entry for this protein is 180470
Ribophorin i; rpn1
DESCRIPTION
Ribophorins I and II (180490) represent proteins that appear to be involved in ribosome binding. They are abundant, highly conserved glycoproteins located exclusively in the membranes of the rough endoplasmic reticulum.CLONING
Using probes derived from a human liver expression library, Crimaudo et al. (1987) isolated and sequenced full-length human cDNA clones encoding ribophorins I and II. The cDNA clones hybridize to mRNA species of 2.5 kb and encode polypeptides of 68.5 and 69.3 kD, respectively. Sequence comparisons and immunoblotting with specific antibodies showed both proteins to be highly conserved throughout a variety of species. However, no relationship between the 2 proteins could be deduced from their primary sequences.GENE FUNCTION
Kelleher et al. (1992) reported that mammalian oligosaccharyltransferase activity is associated with a protein complex composed of ribophorin I, ribophorin II, and a 48-kD oligosaccharyltransferase protein (602202). Rpn1 is a component of the proteasome base. Using in vitro binding assays with purified yeast proteasomes, Elsasser et al. (2002) found that the ubiquitin-like (UBL) domain of recombinant Rad23 (see 600061) interacted with proteasomes through the leucine-rich repeat domain of Rpn1. Yeast Dsk2 (see 300264) also contains a UBL domain, and it competed with Rad23 for proteasome binding.MAPPING
Using cDNA clones, Barton et al. (1987) mapped the RPN1 gene to chromosome 3 in somatic cell hybrids. ... More on the omim web site
May 12, 2019: Protein entry updated
Automatic update: OMIM entry 180470 was added.
Dec. 9, 2018: Protein entry updated
Automatic update: Entry updated from uniprot information.
Oct. 19, 2018: Additional information
Initial protein addition to the database. This entry was referenced in Bryk and co-workers. (2017).