Summary

This gene encodes a type I integral membrane protein found only in the rough endoplasmic reticulum. The encoded protein is part of an N-oligosaccharyl transferase complex that links high mannose oligosaccharides to asparagine residues found in the Asn-X-Ser/Thr consensus motif of nascent polypeptide chains. This protein is similar in sequence to the yeast oligosaccharyl transferase subunit SWP1. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq]

Function

Essential subunit of N-oligosaccharyl transferase enzyme 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.

Disease relevance of RPN2

• OPHN1 and RPN II appeared to be differentially expressed in gastric cancers exhibiting LVI [1].

High impact information on RPN2

• In the case of ribophorin II, it is completely resistant to such proteolysis which is consistent with its luminal disposition and fairly hydrophobic C terminus.(ABSTRACT TRUNCATED AT 250 WORDS)[2]
• Ribophorin I was 85% resistant and ribophorin II 100% resistant to the levels of protease needed to totally eliminate ribosome binding [3].
• The myeloid tumor suppressor gene was localized to an 18-centimorgan interval (approximately equal to 13 Mb) between RPN2 and D20S17 [4].
• Dinucleotide repeat polymorphism at the human ribophorin II locus (RPN2) on chromosome 20q [5].
• What curves alpha-solenoids? Evidence for an alpha-helical toroid structure of Rpn1 and Rpn2 proteins of the 26 S proteasome [6].

Biological context of RPN2

• Among the 17 loci, D20S48 on 20p11.2 and RPN2 on 20q12-13.1 exhibited higher frequencies of LOH, 27.6% and 31.4%, respectively [7].
• Using a radioactive labelled cDNA probe, we have regionally mapped the RPN II gene to human chromosome 20q12-q13.1 by in situ hybridization [8].
• In the present study, by using indirect immunofluorescence technique (IFAT), Western blot, and recombinant antigens of the spore wall (SWP1) and polar tube (PTP1, PTP2, and PTP3 ), we analyzed the IgG antibody response of a laboratory worker who was infected with Encephalitozoon cuniculi [9].
• In this study, the genetic diversity of E. cuniculi was examined at the polar tube protein (PTP) and spore wall protein I (SWP-1) loci [10].

Anatomical context of RPN2

• Ribophorin I and II (RPN I and RPN II), two specific glycoproteins, span the rough regions of the endoplasmic reticulum (RER) and are thought to play an important role either in translocation or in the maintenance of RER [8].
• Studies with human-mouse somatic cell hybrids have localized the gene for RPN I on human chromosome 3q, while RPN II is on chromosome 20 [8].
• Both p63 and ribophorin II were predominantly recovered in rough microsomes and were largely separated from the intermediate compartment marker protein p58 [11].
• In addition, ribophorin II, an integral endoplasmic reticulum protein that is also a component of macroautophagosomes, and LC3, a specific marker of macrophagosomes, demonstrated localization to membranous complexes in HPS-1 melanocytes [12].

Other interactions of RPN2

• In the case of the Tac chimera containing only the luminal domain of RII, which by itself exits from the ER and is rapidly degraded, it is retained in the ER and becomes stabilized when coexpressed with OST48 [13].
• A series of known genes which have not previously been reported to be overexpressed in cancer were also recovered: Hsc70, PBEF, ribophorin II and Ese-3B [14].

Analytical, diagnostic and therapeutic context of RPN2

• N-terminal sequence analysis identified the proteins as ribophorin I, ribophorin II (doublet), and a 50-kDa homologue of Wbp1, a yeast protein essential for N-glycosylation [15].
• Based on the length polymorphism and sequence diversities of the PTP and SWP-1 genes, two simple PCR tests were developed to differentiate E. cuniculi in clinical samples [10].

References