Ube2N Protein is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
| UBE2N Protein |
|---|
| Protein Name | Ubiquitin-Conjugating Enzyme E2 N (UEV1A) |
| Gene | [UBE2N](/genes/ube2n) |
| UniProt ID | [P61079](https://www.uniprot.org/uniprot/P61079) |
| PDB ID | 1XWH, 2GMI, 3H3Z |
| Molecular Weight | 17 kDa |
| Subcellular Localization | Cytoplasm, Nucleus |
| Protein Family | Ubiquitin-conjugating enzyme family |
| Aliases | Ubc13, UEV1A, E2-25K |
UBE2N (Ubiquitin-Conjugating Enzyme E2 N), also known as Ubc13 or UEV1A, is a unique E2 ubiquitin-conjugating enzyme that catalyzes the formation of Lys63-linked polyubiquitin chains. Unlike classical E2 enzymes that generate Lys48-linked chains for proteasomal degradation, UBE2N produces non-degradative ubiquitin signals that regulate diverse cellular processes including NF-κB signaling, DNA damage repair, and immune responses.
¶ Domain Architecture
- Core UBC Domain: Catalytic core (~150 aa) containing the active site
- UEV Domain: N-terminal UEV (Ubiquitin-E2 Variant) domain that lacks catalytic activity
- Dimerization Interface: Forms heterodimers with UBE2V1 or UBE2V2
- Cysteine Residue: Active site cysteine at position 87
- Thioester Formation: Forms Ub~UBE2N thioester intermediate
- HPCS Motif: Conserved motif in E2 active site
UBE2N has distinctive catalytic properties:
- Heterodimer Formation: Partners with UBE2V1 (UEV1A) or UBE2V2 (MMS2)
- Chain Synthesis: Catalyzes Lys63-linked polyubiquitination
- Non-Proteolytic Signaling: Chains serve as signaling platforms rather than degradation signals
- NF-κB Activation: Lys63-Ub chains activate NF-κB transcription factors
- DNA Damage Response: Facilitates recruitment of repair factors to DNA double-strand breaks
- Immune Signaling: Regulates T-cell receptor and innate immune signaling
- Endosomal Trafficking: Modulates receptor internalization and sorting
- Ubiquitously expressed with high levels in brain and immune tissues
- Enriched in postsynaptic densities
- Upregulated in response to cellular stress
- Tau Pathology: Alters tau ubiquitination and aggregation dynamics
- Synaptic Dysfunction: Impaired synaptic ubiquitin signaling
- Neuroinflammation: NF-κB hyperactivation via UBE2N
- α-Synuclein Turnover: Regulates autophagy-lysosomal degradation
- Mitochondrial Quality Control: Involved in mitophagy
- Dopaminergic Vulnerability: Altered in PD brain
- Protein Aggregation: Dysregulated Ub processing in ALS
- RNA Granules: Interaction with ALS-associated RNA-binding proteins
- Axonal Transport: Ubiquitin system deficits
- Inhibitors: Selective UBE2N inhibitors could reduce neuroinflammation
- Activators: Enhancing activity may improve protein clearance
- Modulation: Fine-tuning NF-κB signaling
- No UBE2N-targeted drugs in clinical trials
- Preclinical studies of NF-κB modulators ongoing
- Gene therapy approaches under investigation
- UBE2V1: Essential heterodimer partner
- TRAF6: NF-κB pathway activator
- NEMO: NF-κB essential modifier
- RNF8: DNA damage response
- OPTN: Autophagy receptor
The study of Ube2N Protein 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.