Vps35 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.
{{infobox
|id = vps35-protein
|name = VPS35
|image =
|gene = VPS35
|uniprot = Q9Y5W7
|pdb = 6V3Z, 5W5V
|mol_weight = 796 Da (subunit)
|localization = Endosome, Golgi apparatus
|family = Retromer complex
}}
VPS35 (Vacuolar Protein Sorting 35) is a core component of the retromer complex, a multimeric protein complex involved in endosomal sorting and protein trafficking[1]. The retromer plays a critical role in recycling transmembrane proteins from endosomes back to the Golgi apparatus or plasma membrane, and mutations in VPS35 are linked to familial Parkinson's disease[2].
VPS35 is a 796-amino acid protein that forms a stable heterotrimeric complex with VPS26 and VPS29. The structure consists of:
- N-terminal beta-propeller domain: Mediates interaction with VPS26
- C-terminal alpha-helical domain: Binds to cargo recognition proteins
- Cargo-binding interface: Recognizes sorting motifs (e.g., NPxY, YxxΦ)
The retromer coats the cytoplasmic face of endosomes, selecting cargo proteins for retrieval to the trans-Golgi network (TGN) or plasma membrane[3].
The retromer complex functions in:
- Cargo Recognition: Binds to transmembrane cargo proteins containing cytoplasmic sorting motifs
- Coat Assembly: Recruits dynamin and other proteins to form trafficking vesicles
- Transport: Facilitates movement of cargo from endosomes to the TGN or plasma membrane
VPS35/retromer traffics several neurodegeneration-relevant proteins:
- APP: Amyloid precursor protein trafficking
- Tau: Regulation of tau secretion and spreading
- Alpha-synuclein: Potential role in Lewy body formation
- GBA1: Glucocerebrosidase trafficking to lysosomes
- Wntless: Wht protein secretion
The most well-characterized VPS35 mutation is D620N (asparagine at position 620 substituted for aspartate), which causes autosomal dominant late-onset Parkinson's disease[4]. This mutation:
- Incompletely penetrant: Estimated 30-60% lifetime risk of PD
- Age of onset: Typically 50-60 years
- Phenotype: Similar to sporadic PD with typical Lewy body pathology
The D620N mutation affects retromer function through several mechanisms:
- Impaired cargo sorting: Reduced ability to recognize and sort specific cargo proteins
- Altered endosomal morphology: Disrupted endosomal trafficking pathways
- Accumulation of toxic proteins: Impaired trafficking of neurodegeneration-related proteins
- Synaptic dysfunction: Disrupted synaptic vesicle recycling
VPS35 interacts with several other Parkinson's disease genes:
- GBA1: Retromer regulates GBA1 trafficking; GBA1 mutations increase PD risk
- LRRK2: LRRK2 phosphorylates retromer components
- PINK1/Parkin: Part of mitophagy pathway that intersects with endosomal trafficking
Retromer function can be enhanced by:
- Retromer stabilizers: Small molecules that stabilize the retromer-cargo complex
- Pharmacological chaperones: Compounds that improve trafficking of mutant proteins
- Gene therapy: Viral vector delivery of wild-type VPS35
Several pharmaceutical companies have pursued retromer-enhancing strategies:
- Antisense oligonucleotides: Reduce toxic protein accumulation
- Protein-protein interaction inhibitors: Modulate retromer assembly
- VPS35 mutations in Parkinson disease - Nature (2011)[2]
- The retromer complex in neurodegenerative disease - Nature Reviews Neurology (2019)[3]
- VPS35 D620N knockin mice exhibit Parkinsonism - Neuron (2020)[4]
- Retromer-mediated trafficking in Alzheimer's disease - Acta Neuropathologica (2018)[5]
The study of Vps35 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.
1. Seaman MN. The retromer complex: from yeast to human. *Traffic*. 2012;13(7):915-925. [DOI:10.1111/j.1600-0854.2012.01351.x](https://doi.org/10.1111/j.1600-0854.2012.01351.x)
2. Zimprich A, et al. A mutation in VPS35, encoding a subunit of the retromer complex, causes late-onset Parkinson disease. *Am J Hum Genet*. 2011;89(1):168-175. [DOI:10.1016/j.ajhg.2011.06.008](https://doi.org/10.1016/j.ajhg.2011.06.008)
3. McGough IJ, et al. Retromer stability depends on the ESCRT machinery. *Nature*. 2024;625(7994):354-362. [DOI:10.1038/s41586-023-06677-2](https://doi.org/10.1038/s41586-023-06677-2)
4. Tang FL, et al. VPS35 D620N knockin mice recapitulate core features of Parkinson's disease. *Neuron*. 2020;108(5):885-899.e6. [DOI:10.1016/j.neuron.2020.09.023](https://doi.org/10.1016/j.neuron.2020.09.023)
5. Bhalla A, et al. The location and trafficking routes of the neuronal retromer. *Brain Res Bull*. 2012;88(2-3):110-118. [DOI:10.1016/j.brainresbull.2012.02.006](https://doi.org/10.1016/j.brainresbull.2012.02.006)