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VPS35

Vacuolar protein sorting ortholog 35 (VPS35) is a protein involved in autophagy and is implicated in neurodegenerative diseases, such as Parkinson's disease (PD) and Alzheimer's disease (AD).[1][2][3][4][5] VPS35 is part of a complex called the retromer, which is responsible for transporting select cargo proteins between vesicular structures (e.g., endosomes, lysosomes, vacuoles) and the Golgi apparatus.[1][6][7][8][9] Mutations in the VPS35 gene (VPS35) cause aberrant autophagy, where cargo proteins fail to be transported and dysfunctional or unnecessary proteins fail to be degraded.[5][7] There are numerous pathways affected by altered VPS35 levels and activity, which have clinical significance in neurodegeneration.[1][2][3][4][5] There is therapeutic relevance for VPS35, as interventions aimed at correcting VPS35 function are in speculation.[5][10][11]

Figure showing the retromer complex. The retromer complex recognizes cargo from the endosome. The VPS35-VPS26-VPS29 trimer forms the cargo recognition complex of the retromer.
VPS35
Available structures
PDBOrtholog search: PDBe RCSB
Identifiers
AliasesVPS35, MEM3, PARK17, VPS35 retromer complex component, retromer complex component
External IDsOMIM: 601501 MGI: 1890467 HomoloGene: 6221 GeneCards: VPS35
Orthologs
SpeciesHumanMouse
Entrez
Ensembl
UniProt
RefSeq (mRNA)

NM_018206

NM_022997

RefSeq (protein)

NP_060676

NP_075373

Location (UCSC)Chr 16: 46.66 – 46.69 MbChr 8: 85.99 – 86.03 Mb
PubMed search[14][15]
Wikidata
View/Edit HumanView/Edit Mouse

Gene edit

In humans, VPS35 is transcribed on chromosome 16q11.2 where is spans about 29.6 kilobases and contains 17 exons.[10][11][16][17] It is evolutionarily conserved and required for survival, as mouse knockout studies have demonstrated embryonic lethality.[2][3][6][8][9][10][11] VPS35 levels peak at postnatal days 10-15 and then decline to a low, stable level throughout adulthood.[3] RNA expression of VPS35 is ubiquitous throughout the body, but are higher in the brain, heart, gonads, spleen, and skeletal muscle, and lower in the lung, liver, kidney, and blood leukocytes.[16][17]

 
Crystal structure of the cargo recognition complex. VPS26 (yellow), VPS35 (light blue), and VPS29 (light purple) form a trimer. VPS35 is bound by VPS26 at its N-terminus and by VPS29 at its C-terminus.

Protein edit

VPS35 was first identified in Saccharomyces cerevisiae from a study investigating the formation of lysosome-like vacuoles and sorting of vacuolar proteins.[4][5][17] The protein contains 796 amino acid residues, with a molecular mass of 92 kDa and an isoelectric point of 5.32.[11][16][17]

Structure edit

VPS35 binds with other proteins to form the retromer, an evolutionarily conserved complex that plays a major role in transmembrane protein recycling from endosomes to the trans-Golgi network (TGN).[1][6][7][8][9] VPS35 itself folds into a secondary structure that represents an α-helical solenoid, containing 34 α-helix repeats.[17]

As part of the retromer, VPS35 trimerizes with other vacuolar protein sorting orthologs, VPS26 and VPS29. In less common situations, VPS35 can bind VPS26 and VPS29 alone, creating heterodimers.[5] VPS26 binds the N-terminus of VPS35 at a conserved PRLYL motif (residues 1-172), whereas a C-terminal α-solenoid fold (residues 307-796) binds VPS29.[1][16][17] These VPS orthologs stabilize each other within the retromer; VPS35 knockdown can lead to VPS29 degradation, and vice versa.[5][7] The VPS35, VPS26, and VPS29 trimer forms the cargo recognition complex, a necessary component for the retromer's ability to regulate vesicular sorting.[1][2][3][5][6][7][8][9][10][18] This is achieved by specifically targeting sorting nexins (i.e., SNX1, SNX2, SNX5, SNX6, and SNX32), which anchor the retromer to endosomes and other vesicular structures.[3][11][17][18]

Function edit

 
Mechanistic overview between chaperone-mediated autophagy and macroautophagy. In chaperone-mediate autophagy, proteins are targeted and shuttled to the lysosome, whereas in macroautophagy, proteins and organelles are shuttled to the lysosome in bulk by an autophagosome.

After translation, VPS35 localizes to the endosome, where it, along with the retromer, has been studied in various phagocytotic processes.[4][10][17] Sortilin and the cation-independent mannose-6-phosphate receptor (CI-MPR) regulate lysosome-mediated degradation and are known VPS35 cargo-proteins.[10] The Wiskott Aldrich Syndrome protein and scar homologue (WASH) complex, directly recruited by VPS35, regulates macroautophagy, whereby an autophagosome engulfs select proteins and whole organelles for lysosomal degradation.[10][19] VPS35 also recruits lysosome-associated membrane protein 2a (LAMP2a) to help initiate chaperone-mediated autophagy, whereby a heat shock protein 70kDa protein 8 (HSPA8)-containing complex facilitates degradation of proteins containing a KFERQ signal.[10][19]

Mutations in VPS35 lead to generalized endosomal defects, such as vesicle enlargement and sequestration around the nucleus.[5] These mutations also affect many cellular processes overseen by the retromer complex, including vesicular trafficking, plasma membrane receptor recycling, protein aggregation, mitochondrial function, and dopamine signaling.[7] These processes play a role in neurodegenerative diseases.[1][2][3][4][5]

Clinical significance edit

Parkinson's disease edit

PD is a clinical challenge, presenting itself as the second most common neurodegenerative disease.[11][20] It is characterized by dopaminergic neuron loss in the substantia nigra pars compacta and the toxic aggregation of the α-synuclein protein into Lewy Bodies, all of which cause motor dysfunctions and dopamine deficiency in PD patients.[11][20] VPS35 mutations and dysfunctional retromer-mediated protein sorting and recycling are implicated in neurodegenerative processes relevant to PD.[8]

Genetic variants edit

In 2011, exome sequencing was performed on a Swiss family where all six members developed late-onset, autosomal dominant PD.[3][5][9][11][20][21][22] The sequencing revealed a mutation from an aspartic acid to asparagine at amino acid residue 620 (D620N) in VPS35.[8][9] Sequence alignment of VPS35 orthologs between Homo sapiens, Pan troglodytes, Mus musculus, Rattus norvegicus, Bos taurus, Canis familiaris, Gallus gallus, Xenopus laevis, Danio rerio, Drosophila melanogaster, and Saccharomyces cerevisiae has shown that the 620 position is highly mutagenic with a propensity to substitute aspartic acid with asparagine throughout evolution.[8] Geographically, the VPS35-D620N variant is most prevalent among Caucasian descendants and families in Switzerland, Austria, the United States, Tunisia, Israel, the United Kingdom, France, Germany, and Japan.[2][9][10][22] Other VPS35 variants (e.g., P316S, R32S, R524W, I560T, H599R, M607V) have been identified among some PD patients; however, the VPS35-D620N variant has been the most extensively characterized and is currently the only mutated form of VPS35 confirmed to be pathogenic.[1][7][9] It is currently unknown how frequently the D620N mutation appears in the general population.[17]

Patient characteristics edit

The neurochemistry and clinical presentation between VPS35-induced PD and idiopathic PD are not significantly different.[9][11][21] PD patients with VPS35 mutations experience typical PD symptoms: bradykinesia (91.4%), rigidity (80%), tremor (77.1%), and postural instability (60%).[9][11][16][21] Patients with the VPS35-D620N variant experience a mean age of disease onset between 50–52 years (earlier than classic PD onset of 65–85 years), are typically white (82.9%), and have high familial history (91.4%).[8][10][11][16][21] The VPS35-D620N mutation occurs more frequently in familial PD (~1.3%) than in sporadic PD (0.3%).[11] PD patients harboring the VPS35-D620N mutation follow slow disease progression; cognitive or neuropsychiatric aspects are generally spared.[23] All patients respond well to levodopa therapy, one of the main treatments to alleviate PD symptoms.[9][11] Overall, the VPS35-D620N mutation is relatively rare in PD, with estimated prevalence of 0.115% from over a dozen case studies comprising approximately 22,000 PD patients globally.[9][17] One clinical caveat is that Lewy body pathology has not been fully understood in the context of VPS35-induced PD, as only a single PD patient harboring the VPS35-D620N variant has undergone an autopsy.[9] However, it is known that in brains of sporadic PD patients, there is mislocalized VPS35 in Lewy bodies.[10]

Interactions between VPS35 and PD-linked genes edit

Changes in VPS35 affect levels of leucine-rich repeat kinase 2 (LRRK2), a candidate gene involved in PD that helps vesicular trafficking by phosphorylating Rab proteins.[5][10][17][24] VPS35 knockdown or overexpression of the VPS35-D620N variant can enhance autophosphorylation of LRRK2, increasing its overall activity.[17] Transgenic mice harboring the VPS35-D620N variant have demonstrated altered Rab phosphorylation by LRRK2.[10] In Drosophila, overexpression of VPS35 can rescue mutant LRRK2-induced PD phenotypes.[9][17] The LRRK2 mutation, G2019S, has also been found to decrease VPS35 levels in mouse N2A neuroblastoma cells, indicating an affective mechanism between these factors.[10]

Parkin, an E3 ubiquitin ligase involved in protein degradation, is commonly seen in autosomal recessive juvenile parkinsonism and has known interactions with VPS35.[17] VPS35 overexpression in Drosophila lacking Parkin reverses Parkin-deficient phenotypes, increasing longevity, climbing ability, and decreasing sensitivity to paraquat, a toxic herbicide known to be associated with PD onset in humans.[17] Parkin is known to increase ubiquitination of VPS35.[17] Counterintuitively, this does not lead to proteasomal degradation of VPS35; a functional role is still being investigated.[24] It is proposed that VPS35 may act downstream of Parkin, since overexpression of VPS35-D620N in Parkin knockout mice has not been shown to rescue dopaminergic neuron loss.[17]

Alzheimer's disease edit

AD is the most prominent cause of dementia (60-80%) and affects many cognitive abilities in patients, including word retrieval, memory recall, and other general executive functions necessary for basic self-care.[25] AD pathology typically begins with the formation of amyloid beta (Aβ) plaques in the brain, which trigger an inflammatory response by microglia and cause a cascade of tau accumulation and spreading.[26] These changes result in the degeneration of neurons, leading to a loss of synaptic connections and neurotransmitter signaling.[25][26]

Clinically, low expression of VPS35 in the brain is a risk factor of AD, since it is known that regions high in AD pathology show low VPS35 activity.[5][6][7][27] Specifically, there are decreased levels of VPS35 in the hippocampi of postmortem AD patients relative to healthy patients.[2][7][8][16] This can be modeled in a specific strain of AD-like mice, Tg2576, whereby heterozygous deletion of VPS35 enhances AD phenotypes in the hippocampus and cortex.[9] Humans possessing a VPS35 genetic variant also increases the risk of developing AD.[8] Consequently, AD pathology is linked to aberrant retromer function.[11]

VPS35 knockdown studies have demonstrated increased amyloid precursor protein (APP) and Aβ plaque levels, hallmarks of AD.[3] VPS35 insufficiency reduces transport of endosomes containing APP, ultimately facilitating APP aggregation and formation of Aβ plaques.[1][5][11] Sortilin-related receptor is a cargo protein that interacts with VPS35; it binds APP and delivers APP to the lysosomal system for degradation.[6] Impairment of retromer activity by VPS35 mutation also increases beta-secretase 1 (BACE1) activity, which cleaves larger APPs and enhances Aβ plaque toxicity.[2][3] This is observed in heterozygous mice deficient in VPS35, which have greater amounts of Aβ40 and Aβ42 compared to controls.[1] Decreased expression of VPS35 in Drosophila AD models further shows an increase in Aβ plaque formation, BACE1 activity, memory deficits, and synaptic dysfunction.[6][7][16]

VPS35 deletion in mammalian models of AD is associated with aberrant microglia function and impaired hippocampal development; however, causal variants have yet to be determined.[7] Possibly, VPS35 loss-of-function may impair an inflammatory response in AD, since triggering receptor expressed on myeloid cells 2 (TREM2), a microglial factor associated with inflammation in AD, is a cargo protein of the retromer and VPS35.[17] Tau pathology is also observed in the brains of VPS35-D620N knock-in mice.[10][11]

Pathophysiology edit

Aberrant autophagy edit

The WASH complex is an important component in autophagy and endosome function.[10] It helps form actin patches on endosomal membranes to facilitate their transport to the TGN.[9] The C-terminus of VPS35 binds the WASH complex; through the retromer, this interaction helps distinguish which proteins are retrieved from the TGN.[2][9][17] Compared to non-mutated VPS35, the VPS35-D620N variant has weaker binding affinity to family with sequence similarity 210 member A (FAM21), a component of the WASH complex, leading to autophagic dysfunction.[9][11] A further consequence of impaired WASH complex binding is improper trafficking of autophagy-related protein 9a (ATG9A), a transmembrane protein that facilitates the interaction between LC3 and autophagosomes.[1][11] Disruption in ATG9A trafficking by the VPS35-D620N mutation also decreases WASH complex localization to the endosomes, suggesting a cyclic feedback between mutated VPS35 and ATG9A mislocalization.[3][10][11] Another result of impaired WASH complex binding is the missorting of Cl-MPR and glucose transporter 1, GLUT1, affecting TGN function and energy utilization.[9]

In PD, specifically, iron accumulation can alter the retromer's function in autophagy. Relative to healthy patients, higher amounts of iron are present in the substantia nigra of PD patients, as well as divalent metal transporter 1 (DMT1), a retromer-associated protein that sequesters iron in cells.[16][17] It is thought that the combination of heightened iron concentration and DMT1 activity leads to neuronal death in PD by increasing α-synuclein accumulation.[16] SH-SY5Y cells expressing the VPS35-D620N mutant display DMT1 accumulation.[17] VPS35 downregulation by RNAi allows DMT1 to associate more closely with LAMP2-positive structures, increasing iron concentration in lysosomes and impairing autophagy.[16] This effect is reversed with restoration of VPS35.[16] Holistically, chaperone-mediated autophagy is disrupted with impaired WASH complex function; heterozygous-VPS35 knockout mice and mice with the VPS35-D620N mutation have a reduction in LAMP2a trafficking, which leads to α-synuclein accumulation in the brain and poses an important functional implication in PD.[9][11]

 
Summary of VPS35 pathological functions related to aberrant autophagy. In healthy conditions (left), VPS35 (orange) levels are sufficient and unmutated, AMPA receptors (purple) localize to the synapse, mitochondria are stable, and there is no neuronal degeneration. In VPS35-induced Parkinson's disease (right), VPS35 levels are low or mutated (green), AMPA receptors are absent from the synapse, mitochondria homeostasis is disrupted, and there is neuronal degeneration facilitated by α-synuclein aggregation (red).

Α-synuclein accumulation and dopaminergic neuron loss edit

Deficient VPS35 expression or bearing the VPS35-D620N variant is known to cause α-synuclein aggregation and dopaminergic neuron loss, relevant characteristics in PD.[3][7][10][11][17][20] This has been studied in Drosophila, where VPS35 deficiency leads to α-synuclein accumulation in lysosomes and inappropriate trafficking of CI-MPR and its ligand, cathepsin D, a lysosomal protease that is important for α-synuclein processing.[9][11][20] Knockdown of VPS35 using short hairpin RNA decreases dopamine transporter localization and recycling at the synaptic membrane.[7][8][11] Mouse heterozygous knockouts of VPS35 display PD-like phenotypes into adulthood, including α-synuclein aggregation, motor impairments, and a loss of dopaminergic activity in the substantia nigra and striatum.[9][11] Transgenic mice overexpressing wildtype human α-synuclein have lower levels of VPS35, and viral overexpression of wildtype VPS35, but not mutant VPS35, can restore hippocampal neuronal loss and reduce astrogliosis.[9][11]

It is unclear in animal studies whether the VPS35-D620N variant is sufficient to cause PD pathology. In rats, overexpression by adeno-associated virus (AAV) of human VPS35-D620N does not alter α-synuclein levels, phosphorylation, or PD pathology in dopaminergic neurons in the substantia nigra.[9] However, other studies using rats have shown that introducing the VPS35-D620N variant results in dopaminergic neuronal degeneration in the substantia nigra.[1] Mouse knock-in models of VPS35-D620N display no difference in retromer assembly and stability or protein levels related to endolysosomes, autophagy, mitochondria, or α-synuclein in the brain, although there is a reduction in striatal dopamine around 5 months of age.[9][11] In Drosophila, overexpression of human VPS35-D620N or VPS35-P316S variants shows dopaminergic neuron loss, locomotor impairments, and decreased overall survival relative to human wildtype VPS35.[9]

The Wnt/β-catenin (or Wnt-PCP) pathway may participate in the degeneration of dopaminergic neurons in the midbrain.[16] Inactivity of the retromer complex through VPS35 mutation is thought to degrade Wntless, a membrane protein that regulates Wnt secretion from cells.[16] This leads to downregulated Wnt signaling, increasing vulnerability and degradation of dopaminergic neurons.[16]

Impaired glutamatergic signaling edit

Loss of VPS35 activity decreases signaling efficiency of the excitatory neurotransmitter, glutamate.[17] This has also been shown using a neuron-specific mutation of VPS35-D620N.[17] Mechanistically, this may be mediated by the retromer, where it has been shown to localize to dendritic spines and mediate turnover of the glutamatergic AMPA receptor, GluR1.[9][17] Because of impaired WASH complex binding through the VPS35-D620N mutation, GluR1 can be mistrafficked.[11] Treating mouse hippocampal and cortical neurons with VPS35 small interfering RNA inhibits AMPA receptor trafficking to the dendritic membrane.[7] VPS35-heterozygous knockout mice show similar effects, with an additional observation of impaired dendritic spine development.[9] Human induced pluripotent stem cell-derived dopaminergic neurons with the VPS35-D620N mutation also shift GluR1 localization away from dendritic spines, altering glutamatergic synaptic transmission.[9]

AMPA receptor localization is important for synaptic plasticity, because knockdown of VPS35 in the hippocampus blocks long term potentiation.[3] However, overall synaptic transmission is not profoundly affected.[3] Current knowledge suggests that alteration in VPS35 levels only affects excitatory neuronal signaling, because inhibitory GABA receptors do not appear to be affected by VPS35 or retromer impairment.[3]

Disrupted mitochondrial homeostasis edit

Mitochondria are organelles that undergo oxidative phosphorylation to produce adenosine triphosphate, or ATP, providing energy for the cell to carry out necessary metabolic and homeostatic processes.[10] VPS35 and the retromer help create mitochondria-derived vesicles (MDVs), direct mitochondrial proteins toward degradation as needed, and facilitate cross-talk between vesicles and peroxisomes or lysosomes.[9][17] In disease, deficient or mutated VPS35 causes morphological and functional abnormalities of mitochondria.[10] Mutated VPS35 can lead to mitochondrial membrane instability by ceramide accumulation, which promotes the production of reactive oxygen species.[10] This lowers mitochondrial membrane potential, decreases production of ATP, and impairs bioenergetics.[9] Additionally, some MDVs can be positive for mitochondrial-anchored protein ligase (MAPL), which helps the retromer transport MDVs to peroxisomes for oxidation.[20] Knockdown of VPS35 interferes with this transport.[20]

VPS35 and the retromer also help modulate mitochondrial fusion and fission.[10][11][17] In healthy conditions, VPS35 helps regulate mitochondrial fusion by removing mitochondrial E3 ubiquitin protein ligase 1 (MUL1) from the outer mitochondrial membrane and preventing the degradation of mitofusin 2 (Mfn2).[10] VPS35 loss-of-function increases MUL1 in dopaminergic neurons, leading to ubiquitination and degradation of Mfn2.[10] Treating VPS35-deficient neurons with wildtype VPS35, but not the VPS35-D620N mutant, restores MUL1 levels, and decreases mitochondrial fragmentation.[9] Instead, overexpression of the human VPS35-D620N mutant in cultured rat cortical neurons, M17 cells, and human fibroblasts, and mouse substantia nigral neurons in vivo, causes mitochondrial fragmentation and neuronal loss, relative to a different VPS35 variant, R524W.[9] VPS35 loss-of-function also facilitates mitochondrial fission through the retention of inactive dynamin related protein 1 (Drp1) in the outer mitochondrial membrane.[10]

Therapeutic application edit

Thiophene thiourea derivatives R33 and R55 have been shown to regulate VPS35 levels, restabilizing the retromer complex and reestablishing endosomal function in AD.[10] Rapamycin treatment has also been shown to enhance autophagic function and improve clearance of protein aggregates that pay key roles in PD and AD.[11]

There is potential to modulate VPS35 using viral vectors or genome editing techniques like CRISPR/Cas9, however, given VPS35's ubiquitous role in many homeostatic processes, strict dose control and regional specificity would be necessary to achieve a safe, therapeutic effect.[10] AAV2 vectors have demonstrated safety and efficacy in clinical trials and may be designed to introduce a high yield of non-mutant VPS35 to patients with neurodegenerative diseases.[11]

Speculative therapeutic applications for VPS35 include developing a biomarker assay that detects lower levels of VPS35 in PD or AD patients and identifying cis-regulatory elements within the VPS35 gene for microRNA therapy to reverse VPS35 deficiency.[5]

References edit

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Further reading edit

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  • Andersson B, Wentland MA, Ricafrente JY, Liu W, Gibbs RA (April 1996). "A "double adaptor" method for improved shotgun library construction". Analytical Biochemistry. 236 (1): 107–13. doi:10.1006/abio.1996.0138. PMID 8619474.
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  • Yu W, Andersson B, Worley KC, Muzny DM, Ding Y, Liu W, et al. (April 1997). "Large-scale concatenation cDNA sequencing". Genome Research. 7 (4): 353–8. doi:10.1101/gr.7.4.353. PMC 139146. PMID 9110174.
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vps35, vacuolar, protein, sorting, ortholog, protein, involved, autophagy, implicated, neurodegenerative, diseases, such, parkinson, disease, alzheimer, disease, part, complex, called, retromer, which, responsible, transporting, select, cargo, proteins, betwee. Vacuolar protein sorting ortholog 35 VPS35 is a protein involved in autophagy and is implicated in neurodegenerative diseases such as Parkinson s disease PD and Alzheimer s disease AD 1 2 3 4 5 VPS35 is part of a complex called the retromer which is responsible for transporting select cargo proteins between vesicular structures e g endosomes lysosomes vacuoles and the Golgi apparatus 1 6 7 8 9 Mutations in the VPS35 gene VPS35 cause aberrant autophagy where cargo proteins fail to be transported and dysfunctional or unnecessary proteins fail to be degraded 5 7 There are numerous pathways affected by altered VPS35 levels and activity which have clinical significance in neurodegeneration 1 2 3 4 5 There is therapeutic relevance for VPS35 as interventions aimed at correcting VPS35 function are in speculation 5 10 11 Figure showing the retromer complex The retromer complex recognizes cargo from the endosome The VPS35 VPS26 VPS29 trimer forms the cargo recognition complex of the retromer VPS35Available structuresPDBOrtholog search PDBe RCSBList of PDB id codes2R17IdentifiersAliasesVPS35 MEM3 PARK17 VPS35 retromer complex component retromer complex componentExternal IDsOMIM 601501 MGI 1890467 HomoloGene 6221 GeneCards VPS35Gene location Human Chr Chromosome 16 human 12 Band16q11 2Start46 656 132 bp 12 End46 689 518 bp 12 Gene location Mouse Chr Chromosome 8 mouse 13 Band8 C3 8 41 61 cMStart85 987 021 bp 13 End86 026 431 bp 13 RNA expression patternBgeeHumanMouse ortholog Top expressed incorpus callosumganglionic eminencesuperior frontal gyrusduodenumAchilles tendonislet of Langerhansendometriummonocytethymusprefrontal cortexTop expressed inmedial ganglionic eminencecalvariaparotid glandpyloric antrumdorsomedial hypothalamic nucleusolfactory epitheliumhabenulaparaventricular nucleus of hypothalamusseminal vesiculafacial motor nucleusMore reference expression dataBioGPSMore reference expression dataGene ontologyMolecular functionprotein binding D1 dopamine receptor bindingCellular componentcytoplasm endosome membrane tubular endosome retromer complex lysosomal membrane early endosome extracellular exosome mitochondrion lysosome endosome membrane postsynaptic density retromer cargo selective complex mitochondrion derived vesicle neuron projection neuronal cell body perinuclear region of cytoplasm late endosome cytosol plasma membrane presynapse postsynapse glutamatergic synapseBiological processregulation of protein stability positive regulation of canonical Wnt signaling pathway positive regulation of Wnt protein secretion transcytosis negative regulation of late endosome to lysosome transport retrograde transport endosome to Golgi protein transport regulation of macroautophagy Wnt signaling pathway regulation of mitochondrion organization mitochondrial fragmentation involved in apoptotic process positive regulation of dopamine receptor signaling pathway positive regulation of mitochondrial fission mitochondrion to lysosome transport neurotransmitter receptor transport endosome to plasma membrane regulation of dendritic spine maintenance regulation of terminal button organization lysosome organization positive regulation of gene expression negative regulation of gene expression protein destabilization negative regulation of protein homooligomerization protein localization to organelle voluntary musculoskeletal movement positive regulation of locomotion involved in locomotory behavior positive regulation of dopamine biosynthetic process negative regulation of protein localization negative regulation of lysosomal protein catabolic process transport regulation of cellular protein metabolic process negative regulation of inflammatory response negative regulation of cell death negative regulation of neuron death regulation of presynapse assembly intracellular protein transport synapse assembly viral process neurotransmitter receptor transport endosome to postsynaptic membrane vesicle mediated transport in synapse protein localization to endosomeSources Amigo QuickGOOrthologsSpeciesHumanMouseEntrez5573765114EnsemblENSG00000069329ENSMUSG00000031696UniProtQ96QK1Q9EQH3RefSeq mRNA NM 018206NM 022997RefSeq protein NP 060676NP 075373Location UCSC Chr 16 46 66 46 69 MbChr 8 85 99 86 03 MbPubMed search 14 15 WikidataView Edit HumanView Edit Mouse Contents 1 Gene 2 Protein 2 1 Structure 2 2 Function 3 Clinical significance 3 1 Parkinson s disease 3 1 1 Genetic variants 3 1 2 Patient characteristics 3 1 3 Interactions between VPS35 and PD linked genes 3 2 Alzheimer s disease 4 Pathophysiology 4 1 Aberrant autophagy 4 2 A synuclein accumulation and dopaminergic neuron loss 4 3 Impaired glutamatergic signaling 4 4 Disrupted mitochondrial homeostasis 5 Therapeutic application 6 References 7 Further readingGene editIn humans VPS35 is transcribed on chromosome 16q11 2 where is spans about 29 6 kilobases and contains 17 exons 10 11 16 17 It is evolutionarily conserved and required for survival as mouse knockout studies have demonstrated embryonic lethality 2 3 6 8 9 10 11 VPS35 levels peak at postnatal days 10 15 and then decline to a low stable level throughout adulthood 3 RNA expression of VPS35 is ubiquitous throughout the body but are higher in the brain heart gonads spleen and skeletal muscle and lower in the lung liver kidney and blood leukocytes 16 17 nbsp Crystal structure of the cargo recognition complex VPS26 yellow VPS35 light blue and VPS29 light purple form a trimer VPS35 is bound by VPS26 at its N terminus and by VPS29 at its C terminus Protein editVPS35 was first identified in Saccharomyces cerevisiae from a study investigating the formation of lysosome like vacuoles and sorting of vacuolar proteins 4 5 17 The protein contains 796 amino acid residues with a molecular mass of 92 kDa and an isoelectric point of 5 32 11 16 17 Structure edit VPS35 binds with other proteins to form the retromer an evolutionarily conserved complex that plays a major role in transmembrane protein recycling from endosomes to the trans Golgi network TGN 1 6 7 8 9 VPS35 itself folds into a secondary structure that represents an a helical solenoid containing 34 a helix repeats 17 As part of the retromer VPS35 trimerizes with other vacuolar protein sorting orthologs VPS26 and VPS29 In less common situations VPS35 can bind VPS26 and VPS29 alone creating heterodimers 5 VPS26 binds the N terminus of VPS35 at a conserved PRLYL motif residues 1 172 whereas a C terminal a solenoid fold residues 307 796 binds VPS29 1 16 17 These VPS orthologs stabilize each other within the retromer VPS35 knockdown can lead to VPS29 degradation and vice versa 5 7 The VPS35 VPS26 and VPS29 trimer forms the cargo recognition complex a necessary component for the retromer s ability to regulate vesicular sorting 1 2 3 5 6 7 8 9 10 18 This is achieved by specifically targeting sorting nexins i e SNX1 SNX2 SNX5 SNX6 and SNX32 which anchor the retromer to endosomes and other vesicular structures 3 11 17 18 Function edit nbsp Mechanistic overview between chaperone mediated autophagy and macroautophagy In chaperone mediate autophagy proteins are targeted and shuttled to the lysosome whereas in macroautophagy proteins and organelles are shuttled to the lysosome in bulk by an autophagosome After translation VPS35 localizes to the endosome where it along with the retromer has been studied in various phagocytotic processes 4 10 17 Sortilin and the cation independent mannose 6 phosphate receptor CI MPR regulate lysosome mediated degradation and are known VPS35 cargo proteins 10 The Wiskott Aldrich Syndrome protein and scar homologue WASH complex directly recruited by VPS35 regulates macroautophagy whereby an autophagosome engulfs select proteins and whole organelles for lysosomal degradation 10 19 VPS35 also recruits lysosome associated membrane protein 2a LAMP2a to help initiate chaperone mediated autophagy whereby a heat shock protein 70kDa protein 8 HSPA8 containing complex facilitates degradation of proteins containing a KFERQ signal 10 19 Mutations in VPS35 lead to generalized endosomal defects such as vesicle enlargement and sequestration around the nucleus 5 These mutations also affect many cellular processes overseen by the retromer complex including vesicular trafficking plasma membrane receptor recycling protein aggregation mitochondrial function and dopamine signaling 7 These processes play a role in neurodegenerative diseases 1 2 3 4 5 Clinical significance editParkinson s disease edit PD is a clinical challenge presenting itself as the second most common neurodegenerative disease 11 20 It is characterized by dopaminergic neuron loss in the substantia nigra pars compacta and the toxic aggregation of the a synuclein protein into Lewy Bodies all of which cause motor dysfunctions and dopamine deficiency in PD patients 11 20 VPS35 mutations and dysfunctional retromer mediated protein sorting and recycling are implicated in neurodegenerative processes relevant to PD 8 Genetic variants edit In 2011 exome sequencing was performed on a Swiss family where all six members developed late onset autosomal dominant PD 3 5 9 11 20 21 22 The sequencing revealed a mutation from an aspartic acid to asparagine at amino acid residue 620 D620N in VPS35 8 9 Sequence alignment of VPS35 orthologs between Homo sapiens Pan troglodytes Mus musculus Rattus norvegicus Bos taurus Canis familiaris Gallus gallus Xenopus laevis Danio rerio Drosophila melanogaster and Saccharomyces cerevisiae has shown that the 620 position is highly mutagenic with a propensity to substitute aspartic acid with asparagine throughout evolution 8 Geographically the VPS35 D620N variant is most prevalent among Caucasian descendants and families in Switzerland Austria the United States Tunisia Israel the United Kingdom France Germany and Japan 2 9 10 22 Other VPS35 variants e g P316S R32S R524W I560T H599R M607V have been identified among some PD patients however the VPS35 D620N variant has been the most extensively characterized and is currently the only mutated form of VPS35 confirmed to be pathogenic 1 7 9 It is currently unknown how frequently the D620N mutation appears in the general population 17 Patient characteristics edit The neurochemistry and clinical presentation between VPS35 induced PD and idiopathic PD are not significantly different 9 11 21 PD patients with VPS35 mutations experience typical PD symptoms bradykinesia 91 4 rigidity 80 tremor 77 1 and postural instability 60 9 11 16 21 Patients with the VPS35 D620N variant experience a mean age of disease onset between 50 52 years earlier than classic PD onset of 65 85 years are typically white 82 9 and have high familial history 91 4 8 10 11 16 21 The VPS35 D620N mutation occurs more frequently in familial PD 1 3 than in sporadic PD 0 3 11 PD patients harboring the VPS35 D620N mutation follow slow disease progression cognitive or neuropsychiatric aspects are generally spared 23 All patients respond well to levodopa therapy one of the main treatments to alleviate PD symptoms 9 11 Overall the VPS35 D620N mutation is relatively rare in PD with estimated prevalence of 0 115 from over a dozen case studies comprising approximately 22 000 PD patients globally 9 17 One clinical caveat is that Lewy body pathology has not been fully understood in the context of VPS35 induced PD as only a single PD patient harboring the VPS35 D620N variant has undergone an autopsy 9 However it is known that in brains of sporadic PD patients there is mislocalized VPS35 in Lewy bodies 10 Interactions between VPS35 and PD linked genes edit Changes in VPS35 affect levels of leucine rich repeat kinase 2 LRRK2 a candidate gene involved in PD that helps vesicular trafficking by phosphorylating Rab proteins 5 10 17 24 VPS35 knockdown or overexpression of the VPS35 D620N variant can enhance autophosphorylation of LRRK2 increasing its overall activity 17 Transgenic mice harboring the VPS35 D620N variant have demonstrated altered Rab phosphorylation by LRRK2 10 In Drosophila overexpression of VPS35 can rescue mutant LRRK2 induced PD phenotypes 9 17 The LRRK2 mutation G2019S has also been found to decrease VPS35 levels in mouse N2A neuroblastoma cells indicating an affective mechanism between these factors 10 Parkin an E3 ubiquitin ligase involved in protein degradation is commonly seen in autosomal recessive juvenile parkinsonism and has known interactions with VPS35 17 VPS35 overexpression in Drosophila lacking Parkin reverses Parkin deficient phenotypes increasing longevity climbing ability and decreasing sensitivity to paraquat a toxic herbicide known to be associated with PD onset in humans 17 Parkin is known to increase ubiquitination of VPS35 17 Counterintuitively this does not lead to proteasomal degradation of VPS35 a functional role is still being investigated 24 It is proposed that VPS35 may act downstream of Parkin since overexpression of VPS35 D620N in Parkin knockout mice has not been shown to rescue dopaminergic neuron loss 17 Alzheimer s disease edit AD is the most prominent cause of dementia 60 80 and affects many cognitive abilities in patients including word retrieval memory recall and other general executive functions necessary for basic self care 25 AD pathology typically begins with the formation of amyloid beta Ab plaques in the brain which trigger an inflammatory response by microglia and cause a cascade of tau accumulation and spreading 26 These changes result in the degeneration of neurons leading to a loss of synaptic connections and neurotransmitter signaling 25 26 Clinically low expression of VPS35 in the brain is a risk factor of AD since it is known that regions high in AD pathology show low VPS35 activity 5 6 7 27 Specifically there are decreased levels of VPS35 in the hippocampi of postmortem AD patients relative to healthy patients 2 7 8 16 This can be modeled in a specific strain of AD like mice Tg2576 whereby heterozygous deletion of VPS35 enhances AD phenotypes in the hippocampus and cortex 9 Humans possessing a VPS35 genetic variant also increases the risk of developing AD 8 Consequently AD pathology is linked to aberrant retromer function 11 VPS35 knockdown studies have demonstrated increased amyloid precursor protein APP and Ab plaque levels hallmarks of AD 3 VPS35 insufficiency reduces transport of endosomes containing APP ultimately facilitating APP aggregation and formation of Ab plaques 1 5 11 Sortilin related receptor is a cargo protein that interacts with VPS35 it binds APP and delivers APP to the lysosomal system for degradation 6 Impairment of retromer activity by VPS35 mutation also increases beta secretase 1 BACE1 activity which cleaves larger APPs and enhances Ab plaque toxicity 2 3 This is observed in heterozygous mice deficient in VPS35 which have greater amounts of Ab40 and Ab42 compared to controls 1 Decreased expression of VPS35 in Drosophila AD models further shows an increase in Ab plaque formation BACE1 activity memory deficits and synaptic dysfunction 6 7 16 VPS35 deletion in mammalian models of AD is associated with aberrant microglia function and impaired hippocampal development however causal variants have yet to be determined 7 Possibly VPS35 loss of function may impair an inflammatory response in AD since triggering receptor expressed on myeloid cells 2 TREM2 a microglial factor associated with inflammation in AD is a cargo protein of the retromer and VPS35 17 Tau pathology is also observed in the brains of VPS35 D620N knock in mice 10 11 Pathophysiology editAberrant autophagy edit The WASH complex is an important component in autophagy and endosome function 10 It helps form actin patches on endosomal membranes to facilitate their transport to the TGN 9 The C terminus of VPS35 binds the WASH complex through the retromer this interaction helps distinguish which proteins are retrieved from the TGN 2 9 17 Compared to non mutated VPS35 the VPS35 D620N variant has weaker binding affinity to family with sequence similarity 210 member A FAM21 a component of the WASH complex leading to autophagic dysfunction 9 11 A further consequence of impaired WASH complex binding is improper trafficking of autophagy related protein 9a ATG9A a transmembrane protein that facilitates the interaction between LC3 and autophagosomes 1 11 Disruption in ATG9A trafficking by the VPS35 D620N mutation also decreases WASH complex localization to the endosomes suggesting a cyclic feedback between mutated VPS35 and ATG9A mislocalization 3 10 11 Another result of impaired WASH complex binding is the missorting of Cl MPR and glucose transporter 1 GLUT1 affecting TGN function and energy utilization 9 In PD specifically iron accumulation can alter the retromer s function in autophagy Relative to healthy patients higher amounts of iron are present in the substantia nigra of PD patients as well as divalent metal transporter 1 DMT1 a retromer associated protein that sequesters iron in cells 16 17 It is thought that the combination of heightened iron concentration and DMT1 activity leads to neuronal death in PD by increasing a synuclein accumulation 16 SH SY5Y cells expressing the VPS35 D620N mutant display DMT1 accumulation 17 VPS35 downregulation by RNAi allows DMT1 to associate more closely with LAMP2 positive structures increasing iron concentration in lysosomes and impairing autophagy 16 This effect is reversed with restoration of VPS35 16 Holistically chaperone mediated autophagy is disrupted with impaired WASH complex function heterozygous VPS35 knockout mice and mice with the VPS35 D620N mutation have a reduction in LAMP2a trafficking which leads to a synuclein accumulation in the brain and poses an important functional implication in PD 9 11 nbsp Summary of VPS35 pathological functions related to aberrant autophagy In healthy conditions left VPS35 orange levels are sufficient and unmutated AMPA receptors purple localize to the synapse mitochondria are stable and there is no neuronal degeneration In VPS35 induced Parkinson s disease right VPS35 levels are low or mutated green AMPA receptors are absent from the synapse mitochondria homeostasis is disrupted and there is neuronal degeneration facilitated by a synuclein aggregation red A synuclein accumulation and dopaminergic neuron loss edit Deficient VPS35 expression or bearing the VPS35 D620N variant is known to cause a synuclein aggregation and dopaminergic neuron loss relevant characteristics in PD 3 7 10 11 17 20 This has been studied in Drosophila where VPS35 deficiency leads to a synuclein accumulation in lysosomes and inappropriate trafficking of CI MPR and its ligand cathepsin D a lysosomal protease that is important for a synuclein processing 9 11 20 Knockdown of VPS35 using short hairpin RNA decreases dopamine transporter localization and recycling at the synaptic membrane 7 8 11 Mouse heterozygous knockouts of VPS35 display PD like phenotypes into adulthood including a synuclein aggregation motor impairments and a loss of dopaminergic activity in the substantia nigra and striatum 9 11 Transgenic mice overexpressing wildtype human a synuclein have lower levels of VPS35 and viral overexpression of wildtype VPS35 but not mutant VPS35 can restore hippocampal neuronal loss and reduce astrogliosis 9 11 It is unclear in animal studies whether the VPS35 D620N variant is sufficient to cause PD pathology In rats overexpression by adeno associated virus AAV of human VPS35 D620N does not alter a synuclein levels phosphorylation or PD pathology in dopaminergic neurons in the substantia nigra 9 However other studies using rats have shown that introducing the VPS35 D620N variant results in dopaminergic neuronal degeneration in the substantia nigra 1 Mouse knock in models of VPS35 D620N display no difference in retromer assembly and stability or protein levels related to endolysosomes autophagy mitochondria or a synuclein in the brain although there is a reduction in striatal dopamine around 5 months of age 9 11 In Drosophila overexpression of human VPS35 D620N or VPS35 P316S variants shows dopaminergic neuron loss locomotor impairments and decreased overall survival relative to human wildtype VPS35 9 The Wnt b catenin or Wnt PCP pathway may participate in the degeneration of dopaminergic neurons in the midbrain 16 Inactivity of the retromer complex through VPS35 mutation is thought to degrade Wntless a membrane protein that regulates Wnt secretion from cells 16 This leads to downregulated Wnt signaling increasing vulnerability and degradation of dopaminergic neurons 16 Impaired glutamatergic signaling edit Loss of VPS35 activity decreases signaling efficiency of the excitatory neurotransmitter glutamate 17 This has also been shown using a neuron specific mutation of VPS35 D620N 17 Mechanistically this may be mediated by the retromer where it has been shown to localize to dendritic spines and mediate turnover of the glutamatergic AMPA receptor GluR1 9 17 Because of impaired WASH complex binding through the VPS35 D620N mutation GluR1 can be mistrafficked 11 Treating mouse hippocampal and cortical neurons with VPS35 small interfering RNA inhibits AMPA receptor trafficking to the dendritic membrane 7 VPS35 heterozygous knockout mice show similar effects with an additional observation of impaired dendritic spine development 9 Human induced pluripotent stem cell derived dopaminergic neurons with the VPS35 D620N mutation also shift GluR1 localization away from dendritic spines altering glutamatergic synaptic transmission 9 AMPA receptor localization is important for synaptic plasticity because knockdown of VPS35 in the hippocampus blocks long term potentiation 3 However overall synaptic transmission is not profoundly affected 3 Current knowledge suggests that alteration in VPS35 levels only affects excitatory neuronal signaling because inhibitory GABA receptors do not appear to be affected by VPS35 or retromer impairment 3 Disrupted mitochondrial homeostasis edit Mitochondria are organelles that undergo oxidative phosphorylation to produce adenosine triphosphate or ATP providing energy for the cell to carry out necessary metabolic and homeostatic processes 10 VPS35 and the retromer help create mitochondria derived vesicles MDVs direct mitochondrial proteins toward degradation as needed and facilitate cross talk between vesicles and peroxisomes or lysosomes 9 17 In disease deficient or mutated VPS35 causes morphological and functional abnormalities of mitochondria 10 Mutated VPS35 can lead to mitochondrial membrane instability by ceramide accumulation which promotes the production of reactive oxygen species 10 This lowers mitochondrial membrane potential decreases production of ATP and impairs bioenergetics 9 Additionally some MDVs can be positive for mitochondrial anchored protein ligase MAPL which helps the retromer transport MDVs to peroxisomes for oxidation 20 Knockdown of VPS35 interferes with this transport 20 VPS35 and the retromer also help modulate mitochondrial fusion and fission 10 11 17 In healthy conditions VPS35 helps regulate mitochondrial fusion by removing mitochondrial E3 ubiquitin protein ligase 1 MUL1 from the outer mitochondrial membrane and preventing the degradation of mitofusin 2 Mfn2 10 VPS35 loss of function increases MUL1 in dopaminergic neurons leading to ubiquitination and degradation of Mfn2 10 Treating VPS35 deficient neurons with wildtype VPS35 but not the VPS35 D620N mutant restores MUL1 levels and decreases mitochondrial fragmentation 9 Instead overexpression of the human VPS35 D620N mutant in cultured rat cortical neurons M17 cells and human fibroblasts and mouse substantia nigral neurons in vivo causes mitochondrial fragmentation and neuronal loss relative to a different VPS35 variant R524W 9 VPS35 loss of function also facilitates mitochondrial fission through the retention of inactive dynamin related protein 1 Drp1 in the outer mitochondrial membrane 10 Therapeutic application editThiophene thiourea derivatives R33 and R55 have been shown to regulate VPS35 levels restabilizing the retromer complex and reestablishing endosomal function in AD 10 Rapamycin treatment has also been shown to enhance autophagic function and improve clearance of protein aggregates that pay key roles in PD and AD 11 There is potential to modulate VPS35 using viral vectors or genome editing techniques like CRISPR Cas9 however given VPS35 s ubiquitous role in many homeostatic processes strict dose control and regional specificity would be necessary to achieve a safe therapeutic effect 10 AAV2 vectors have demonstrated safety and efficacy in clinical trials and may be designed to introduce a high yield of non mutant VPS35 to patients with neurodegenerative diseases 11 Speculative therapeutic applications for VPS35 include developing a biomarker assay that detects lower levels of VPS35 in PD or AD patients and identifying cis regulatory elements within the VPS35 gene for microRNA therapy to reverse VPS35 deficiency 5 References edit a b c d e f g h i j k l Reitz C April 2015 The role of the retromer complex in aging related neurodegeneration a molecular and genomic review Molecular Genetics and Genomics 290 2 413 27 doi 10 1007 s00438 014 0939 9 PMC 4363161 PMID 25332075 a b c d e f g h i Reitz C May 2018 Retromer Dysfunction and Neurodegenerative Disease Current Genomics 19 4 279 288 doi 10 2174 1389202919666171024122809 PMC 5930449 PMID 29755290 a b c d e f g h i j k l m n o Brodin L Shupliakov O 2018 Retromer in Synaptic Function and Pathology Frontiers in Synaptic Neuroscience 10 37 doi 10 3389 fnsyn 2018 00037 PMC 6207580 PMID 30405388 a b c d e Follett J Bugarcic A Collins BM Teasdale RD 2017 07 01 Retromer s Role in Endosomal Trafficking and Impaired Function in Neurodegenerative Diseases Current Protein amp Peptide Science 18 7 687 701 doi 10 2174 1389203717666160311121246 PMID 26965691 a b c d e f g h i j k l m n o Trousdale C Kim K November 2015 Retromer Structure function and roles in mammalian disease European Journal of Cell Biology 94 11 513 21 doi 10 1016 j ejcb 2015 07 002 PMID 26220253 a b c d e f g Vagnozzi AN Li JG Chiu J Razmpour R Warfield R Ramirez SH Pratico D July 2019 VPS35 regulates tau phosphorylation and neuropathology in tauopathy Molecular Psychiatry 26 11 6992 7005 doi 10 1038 s41380 019 0453 x PMC 6949432 PMID 31289348 a b c d e f g h i j k l m n Rahman AA Morrison BE March 2019 Contributions of VPS35 Mutations to Parkinson s Disease Neuroscience 401 1 10 doi 10 1016 j neuroscience 2019 01 006 PMC 6422337 PMID 30660673 a b c d e f g h i j k Vilarino Guell C Wider C Ross OA Dachsel JC Kachergus JM Lincoln SJ et al July 2011 VPS35 mutations in Parkinson disease American Journal of Human Genetics 89 1 162 7 doi 10 1016 j ajhg 2011 06 001 PMC 3135796 PMID 21763482 a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag Williams ET Chen X Moore DJ 2017 01 01 VPS35 the Retromer Complex and Parkinson s Disease Journal of Parkinson s Disease 7 2 219 233 doi 10 3233 JPD 161020 PMC 5438477 PMID 28222538 a b c d e f g h i j k l m n o p q r s t u v w x y z aa Cutillo G Simon DK Eleuteri S November 2020 VPS35 and the mitochondria Connecting the dots in Parkinson s disease pathophysiology Neurobiology of Disease 145 105056 doi 10 1016 j nbd 2020 105056 PMID 32853677 S2CID 221277514 a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad Eleuteri S Albanese A 2019 12 17 VPS35 Based Approach A Potential Innovative Treatment in Parkinson s Disease Frontiers in Neurology 10 1272 doi 10 3389 fneur 2019 01272 PMC 6928206 PMID 31920908 a b c GRCh38 Ensembl release 89 ENSG00000069329 Ensembl May 2017 a b c GRCm38 Ensembl release 89 ENSMUSG00000031696 Ensembl May 2017 Human PubMed Reference National Center for Biotechnology Information U S National Library of Medicine Mouse PubMed Reference National Center for Biotechnology Information U S National Library of Medicine a b c d e f g h i j k l m n o Deng H Gao K Jankovic J May 2013 The VPS35 gene and Parkinson s disease Movement Disorders 28 5 569 75 doi 10 1002 mds 25430 PMID 23536430 S2CID 16641707 a b c d e f g h i j k l m n o p q r s t u v w x y z aa Sassone J Reale C Dati G Regoni M Pellecchia MT Garavaglia B April 2020 The Role of VPS35 in the Pathobiology of Parkinson s Disease Cellular and Molecular Neurobiology 41 2 199 227 doi 10 1007 s10571 020 00849 8 PMID 32323152 S2CID 216076582 a b Verges M 2016 01 01 Jeon KW ed Retromer in Polarized Protein Transport International Review of Cell and Molecular Biology 323 Academic Press 129 79 doi 10 1016 bs ircmb 2015 12 005 ISBN 9780128048085 PMID 26944621 a b Ghosh R Pattison JS 2018 Macroautophagy and Chaperone Mediated Autophagy in Heart Failure The Known and the Unknown Oxidative Medicine and Cellular Longevity 2018 8602041 doi 10 1155 2018 8602041 PMC 5822756 PMID 29576856 a b c d e f g Bose A Beal MF October 2016 Mitochondrial dysfunction in Parkinson s disease Journal of Neurochemistry 139 S1 216 231 doi 10 1111 jnc 13731 PMID 27546335 S2CID 32612919 a b c d Weissbach A Wittke C Kasten M Klein C 2019 01 01 Stamelou M Hoglinger GU eds Atypical Parkinson s disease genetic International Review of Neurobiology 149 Academic Press 207 235 doi 10 1016 bs irn 2019 10 011 ISBN 9780128177303 PMID 31779813 S2CID 208357146 a b Kim CY Alcalay RN April 2017 Genetic Forms of Parkinson s Disease Seminars in Neurology 37 2 135 146 doi 10 1055 s 0037 1601567 PMID 28511254 S2CID 635105 Lunati A Lesage S Brice A November 2018 The genetic landscape of Parkinson s disease PDF Revue Neurologique International SFN SOMFA Meeting 2018 174 9 628 643 doi 10 1016 j neurol 2018 08 004 PMID 30245141 a b Nguyen M Wong YC Ysselstein D Severino A Krainc D February 2019 Synaptic Mitochondrial and Lysosomal Dysfunction in Parkinson s Disease Trends in Neurosciences 42 2 140 149 doi 10 1016 j tins 2018 11 001 PMC 6452863 PMID 30509690 a b Abeysinghe AA Deshapriya RD Udawatte C September 2020 Alzheimer s disease a review of the pathophysiological basis and therapeutic interventions Life Sciences 256 117996 doi 10 1016 j lfs 2020 117996 PMID 32585249 S2CID 220075087 a b Boche D Nicoll JA December 2020 Invited Review Understanding cause and effect in Alzheimer s pathophysiology Implications for clinical trials Neuropathology and Applied Neurobiology 46 7 623 640 doi 10 1111 nan 12642 PMID 32643143 S2CID 220429715 Qureshi YH Baez P Reitz C September 2020 Endosomal Trafficking in Alzheimer s Disease Parkinson s Disease and Neuronal Ceroid Lipofuscinosis Molecular and Cellular Biology 40 19 doi 10 1128 MCB 00262 20 PMC 7491951 PMID 32690545 Further reading editMaruyama K Sugano S January 1994 Oligo capping a simple method to replace the cap structure of eukaryotic mRNAs with oligoribonucleotides Gene 138 1 2 171 4 doi 10 1016 0378 1119 94 90802 8 PMID 8125298 Andersson B Wentland MA Ricafrente JY Liu W Gibbs RA April 1996 A double adaptor method for improved shotgun library construction Analytical Biochemistry 236 1 107 13 doi 10 1006 abio 1996 0138 PMID 8619474 Bonaldo MF Lennon G Soares MB September 1996 Normalization and subtraction two approaches to facilitate gene discovery Genome Research 6 9 791 806 doi 10 1101 gr 6 9 791 PMID 8889548 Yu W Andersson B Worley KC Muzny DM Ding Y Liu W et al April 1997 Large scale concatenation cDNA sequencing Genome Research 7 4 353 8 doi 10 1101 gr 7 4 353 PMC 139146 PMID 9110174 Suzuki Y Yoshitomo Nakagawa K Maruyama K Suyama A Sugano S October 1997 Construction and characterization of a full length enriched and a 5 end enriched cDNA library Gene 200 1 2 149 56 doi 10 1016 S0378 1119 97 00411 3 PMID 9373149 Edgar AJ Polak JM November 2000 Human homologues of yeast vacuolar protein sorting 29 and 35 Biochemical and Biophysical Research Communications 277 3 622 30 doi 10 1006 bbrc 2000 3727 PMID 11062004 Hartley JL Temple GF Brasch MA November 2000 DNA cloning using in vitro site specific recombination Genome Research 10 11 1788 95 doi 10 1101 gr 143000 PMC 310948 PMID 11076863 Haft CR de la Luz Sierra M Bafford R Lesniak MA Barr VA Taylor SI December 2000 Human orthologs of yeast vacuolar protein sorting proteins Vps26 29 and 35 assembly into multimeric complexes Molecular Biology of the Cell 11 12 4105 16 doi 10 1091 mbc 11 12 4105 PMC 15060 PMID 11102511 Verges M Luton F Gruber C Tiemann F Reinders LG Huang L et al August 2004 The mammalian retromer regulates transcytosis of the polymeric immunoglobulin receptor Nature Cell Biology 6 8 763 9 doi 10 1038 ncb1153 PMID 15247922 S2CID 22296469 Mingot JM Bohnsack MT Jakle U Gorlich D August 2004 Exportin 7 defines a novel general nuclear export pathway The EMBO Journal 23 16 3227 36 doi 10 1038 sj emboj 7600338 PMC 514512 PMID 15282546 Retrieved from https en wikipedia org w index php title VPS35 amp oldid 1190848851, wikipedia, wiki, book, books, library,

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