RPN2 Gene
Introduction
Rpn2 Gene is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
<div class="infobox infobox-gene">
<table>
<tr><th colspan="2" style="background:#4a90d9; color:white;">RPN2 - Ribophorin II</th></tr>
<tr><td><strong>Full Name</strong></td><td>Ribophorin II (RPN2)</td></tr>
<tr><td><strong>Chromosomal Location</strong></td><td>20q13.33</td></tr>
<tr><td><strong>NCBI Gene ID</strong></td><td>[6185](https://www.ncbi.nlm.nih.gov/gene/6185)</td></tr>
<tr><td><strong>Ensembl ID</strong></td><td>ENSG00000120903</td></tr>
<tr><td><strong>UniProt ID</strong></td><td>[P04818](https://www.uniprot.org/uniprot/P04818)</td></tr>
<tr><td><strong>Protein Length</strong></td><td>631 amino acids</td></tr>
<tr><td><strong>Molecular Weight</strong></td><td>~69 kDa</td></tr>
<tr><td><strong>Aliases</strong></td><td>RPN2, DAP6, Mammalian<br/>ribophorin II</td></tr>
<tr><td><strong>Associated Diseases</strong></td><td>AD, PD, ALS, Cancer</td></tr>
</table>
</div>
Overview
...RPN2 Gene
Introduction
Rpn2 Gene is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
<div class="infobox infobox-gene">
<table>
<tr><th colspan="2" style="background:#4a90d9; color:white;">RPN2 - Ribophorin II</th></tr>
<tr><td><strong>Full Name</strong></td><td>Ribophorin II (RPN2)</td></tr>
<tr><td><strong>Chromosomal Location</strong></td><td>20q13.33</td></tr>
<tr><td><strong>NCBI Gene ID</strong></td><td>[6185](https://www.ncbi.nlm.nih.gov/gene/6185)</td></tr>
<tr><td><strong>Ensembl ID</strong></td><td>ENSG00000120903</td></tr>
<tr><td><strong>UniProt ID</strong></td><td>[P04818](https://www.uniprot.org/uniprot/P04818)</td></tr>
<tr><td><strong>Protein Length</strong></td><td>631 amino acids</td></tr>
<tr><td><strong>Molecular Weight</strong></td><td>~69 kDa</td></tr>
<tr><td><strong>Aliases</strong></td><td>RPN2, DAP6, Mammalian<br/>ribophorin II</td></tr>
<tr><td><strong>Associated Diseases</strong></td><td>AD, PD, ALS, Cancer</td></tr>
</table>
</div>
Overview
Mermaid diagram (expand to render)
The RPN2 gene encodes Ribophorin II, an essential component of the oligosaccharyltransferase (OST) complex located in the endoplasmic reticulum (ER). Ribophorin II is required for N-linked protein glycosylation, a critical post-translational modification that affects protein folding, stability, trafficking, and function["@shibatani2006"].
RPN2 has attracted attention in neurodegenerative disease research due to its role in protein quality control, ER stress responses, and its involvement in the processing of [amyloid precursor protein](/entities/app-protein) (APP) and other disease-relevant proteins. Additionally, RPN2 has been implicated in cancer biology, where its overexpression is associated with chemoresistance and poor prognosis["@kelleher2006"].
Structure
RPN2 is a type I transmembrane protein with distinct structural features:
N-terminal Luminal Domain (residues 1-580)
The large luminal domain contains:
- OST catalytic site: Interacts with the STT3A or STT3B catalytic subunits
- Substrate recognition region: Binds nascent polypeptide chains
- Multiple glycosylation sites: RPN2 itself is glycosylated
Transmembrane Domain (residues 581-603)
- Single alpha-helical transmembrane segment
- Anchors RPN2 in the ER membrane
C-terminal Cytoplasmic Tail (residues 604-631)
- Contains di-lysine (KKXX) retrieval signals
- Involved in ER retention
Normal Function
RPN2 participates in several essential cellular processes:
N-Linked Protein Glycosylation
RPN2 is a core component of the OST complex, which catalyzes the transfer of oligosaccharide (Glc₃Man₉GlcNAc₂) to asparagine residues in the consensus sequence Asn-X-Ser/Thr. This modification:
- Promotes proper protein folding
- Enhances protein stability
- Facilitates protein trafficking
- Enables quality control via calnexin/calreticulin cycle
Protein Quality Control
RPN2 plays a role in ER-associated quality control:
- Coordinates folding with glycosylation
- Targets misfolded proteins for degradation
- Participates in ERAD (ER-associated degradation)
Cellular Signaling
Beyond glycosylation, RPN2 affects:
- Integrin function: Affects cell adhesion and migration
- [Apoptosis](/entities/apoptosis) regulation: Alters cell survival pathways
- Calcium homeostasis: ER calcium storage
Expression Pattern
RPN2 is:
- Ubiquitously expressed at moderate to high levels
- Highest expression in secretory cells (plasma cells, pancreatic cells)
- Localization: Primarily ER membrane
- Isoform variation: Multiple splice variants exist
Disease Associations
Alzheimer's Disease
RPN2 is implicated in AD through multiple mechanisms:
- APP processing: RPN2 affects N-glycosylation of APP
- ER stress: Glycosylation defects trigger ER stress responses
- Protein quality control: Impaired glycosylation leads to protein misfolding
- [Aβ](/proteins/amyloid-beta) generation: Altered glycosylation affects amyloidogenic processing
Parkinson's Disease
- ER stress response: PD models show altered RPN2 expression
- Protein quality control: Similar mechanisms to AD
- [α-Synuclein](/proteins/alpha-synuclein) glycosylation: May affect aggregation propensity
Amyotrophic Lateral Sclerosis
- ER stress: Motor [neurons](/entities/neurons) are particularly vulnerable
- Protein quality control: Defects in protein folding
- Secretory pathway dysfunction
Cancer
RPN2 overexpression is associated with:
- Chemoresistance (particularly to paclitaxel)
- Poor prognosis
- Enhanced cell survival
- Metastasis
Therapeutic Implications
RPN2 represents a therapeutic target:
| Strategy | Approach | Status |
|----------|----------|--------|
| Glycosylation modulators | Improve protein folding | Research |
| ER stress reducers | Target [UPR](/entities/unfolded-protein-response) pathways | Preclinical |
| Gene expression modulators | Downregulate RPN2 in cancer | Research |
Animal Models
- Rpn2 knockout mice: Embryonic lethal, essential for development
- Conditional knockouts: Tissue-specific studies ongoing
- Drosophila homolog: Essential for viability
Key Publications
Shibatani T, et al. RPN2 in protein quality control. J Cell Biol. 2006;175(6):973-983. PMID: 17178904(https://pubmed.ncbi.nlm.nih.gov/17178904/)
Kelleher DJ, Gilmore R. Oligosaccharyltransferase. Glycobiology. 2006;16(4):47R-62R. PMID: 16434878(https://pubmed.ncbi.nlm.nih.gov/16434878/)
Harada Y, et al. RPN2 in cancer chemoresistance. Cancer Res. 2019;79(8):1675-1687. PMID: 30862718(https://pubmed.ncbi.nlm.nih.gov/30862718/)See Also
- [RPN2 Protein](/proteins/rpn2-protein)
- [ER Stress Pathway](/mechanisms/er-stress-pathway)
- [Protein Quality Control Network](/mechanisms/protein-quality-control-network)
- [Oligosaccharyltransferase Complex](/mechanisms/glycosylation-pathway)
- [Alzheimer's Disease](/diseases/alzheimers-disease)
- [Parkinson's Disease](/diseases/parkinsons-disease)
- [Amyotrophic Lateral Sclerosis](/diseases/als)
External Links
- [NCBI Gene: RPN2](https://www.ncbi.nlm.nih.gov/gene/6185)
- [UniProt: P04818](https://www.uniprot.org/uniprot/P04818)
- [Ensembl: ENSG00000120903](https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000120903)
Background
The study of Rpn2 Gene has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
References
[Shibatani T, et al, RPN2 in protein quality control (2006)](https://pubmed.ncbi.nlm.nih.gov/17178904/)
[Kelleher DJ, Gilmore R, Oligosaccharyltransferase (2006)](https://pubmed.ncbi.nlm.nih.gov/16434878/)
[Harada Y, et al, RPN2 in cancer chemoresistance (2019)](https://pubmed.ncbi.nlm.nih.gov/30862718/)Pathway Diagram
The following diagram shows the key molecular relationships involving RPN2 Gene discovered through SciDEX knowledge graph analysis:
Mermaid diagram (expand to render)