In vivo protein complementation demonstrates direct detection of presynaptic α-synuclein oligomerization and age-dependent accumulation of 8-16mer oligomer species
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE134462 | GEO | 2019/07/19
REPOSITORIES: GEO
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2025-02-14 | GSE288965 | GEO
Project description:To uncover new disease-associated genes and their relevant mechanisms, we carried out a gene microarray analysis based on a Parkinson’s disease (PD) in vitro model induced by a-synuclein oligomers. The result do help to reveal the mRNA and lncRNA profile in a-syn induced cells and rotenone-stimulated cells.
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Project description:Parkinson disease (PD) is closely linked to the misfolding and accumulation of α-synuclein (α-syn) into Lewy bodies. HtrA1 is a PDZ serine protease that degrades fibrillar tau, which is associated with Alzheimer disease (AD). Further, inactivating mutations to mitochondrial HtrA2 have been implicated in PD. Here, we establish that HtrA1 inhibits the aggregation of α-syn as well as FUS and TDP-43, which are implicated in amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). We demonstrate that the protease domain of HtrA1 is necessary and sufficient for inhibition of aggregation, yet this activity is independent of HtrA1 proteolytic activity. Further, we find that HtrA1 also disaggregates preformed α-syn fibrils, which may promote their clearance. Treatment of α-syn fibrils with HtrA1 renders α-syn incapable of seeding the aggregation of endogenous α-syn in mammalian biosensor cells. We find that HtrA1 remodels α-syn by specifically targeting the NAC domain, which is the key domain that catalyzes α-syn oligomerization and fibrillization. Finally, in a primary neuron model of α-syn aggregation, we show that HtrA1 and its proteolytically inactive form both detoxify α-syn and prevent the formation of hyperphosphorylated α-syn accumulations. Our findings suggest that HtrA1 prevents aggregation and promotes disaggregation of multiple disease-associated proteins, and may be a therapeutic target for treating a range of neurodegenerative disorders.
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Project description:Parkinson disease (PD) is closely linked to the misfolding and accumulation of α-synuclein (α-syn) into Lewy bodies. HTRA1 is a PDZ serine protease that degrades fibrillar tau, which is associated with Alzheimer disease (AD). Further, inactivating mutations to mitochondrial HTRA2 have been implicated in PD. Here, we establish that HTRA1 inhibits the aggregation of α-syn as well as FUS and TDP-43, which are implicated in amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). We demonstrate that the protease domain of HTRA1 is necessary and sufficient for inhibition of aggregation, yet this activity is independent of HTRA1 proteolytic activity. Further, we find that HTRA1 also disaggregates preformed α-syn fibrils, which may promote their clearance. Treatment of α-syn fibrils with HTRA1 renders α-syn incapable of seeding the aggregation of endogenous α-syn in mammalian biosensor cells. We find that HTRA1 remodels α-syn by specifically targeting the NAC domain, which is the key domain that catalyzes α-syn oligomerization and fibrillization. Finally, in a primary neuron model of α-syn aggregation, we show that HTRA1 and its proteolytically inactive form both detoxify α-syn and prevent the formation of hyperphosphorylated α-syn accumulations. Our findings suggest that HTRA1 prevents aggregation and promotes disaggregation of multiple disease-associated proteins, and may be a therapeutic target for treating a range of neurodegenerative disorders.
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Project description:Kuznetsov2016(II) - α-syn aggregation
kinetics in Parkinson's
This theoretical model uses 2-step Finke-Watzky (FW) kinetics
todescribe the production, misfolding, aggregation, transport and
degradation of α-syn that may lead to Parkinson's Disease
(PD). Deregulated α-syn degradation is predicted to be
crucialfor PD pathogenesis.
This model is described in the article:
What can trigger the onset
of Parkinson's disease - A modeling study based on a
compartmental model of α-synuclein transport and aggregation in
neurons.
Kuznetsov IA, Kuznetsov AV.
Math Biosci 2016 Aug; 278: 22-29
Abstract:
The aim of this paper is to develop a minimal model
describing events leading to the onset of Parkinson's disease
(PD). The model accounts for α-synuclein (α-syn) production in
the soma, transport toward the synapse, misfolding, and
aggregation. The production and aggregation of polymeric α-syn
is simulated using a minimalistic 2-step Finke-Watzky model. We
utilized the developed model to analyze what changes in a
healthy neuron are likely to lead to the onset of α-syn
aggregation. We checked the effects of interruption of α-syn
transport toward the synapse, entry of misfolded (infectious)
α-syn into the somatic and synaptic compartments, increasing
the rate of α-syn synthesis in the soma, and failure of α-syn
degradation machinery. Our model suggests that failure of α-syn
degradation machinery is probably the most likely cause for the
onset of α-syn aggregation leading to PD.
This model is hosted on
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and identified by:
BIOMD0000000615.
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To the extent possible under law, all copyright and related or
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Public Domain Dedication for more information.
2024-09-02 | BIOMD0000000615 | BioModels
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Project description:The aggregation of amyloid beta (Aβ) peptide is associated with Alzheimer’s disease (AD) pathogenesis. Cell membrane composition, especially monosialotetrahexosylganglioside (GM1), is known to promote the formation of Aβ fibrils, yet little is known about the roles of GM1 in the early steps of Aβ oligomer formation. Here, by using GM1-contained liposomes as a mimic of neuronal cell membrane, we demonstrate that GM1 is a critical trigger of Aβ oligomerization and aggregation. We find that GM1 not only promotes the formation of Aβ fibrils, but also facilitates the maintenance of Aβ oligomers on liposome membranes. We structurally characterize the Aβ oligomers formed on the membrane and find that GM1 captures Aβ by binding to its arginine-5 residue. To interrogate the mechanism of Aβ oligomer toxicity, we design a new liposome-based Ca2+-encapsulation assay and provide new evidence for the Aβ ion channel hypothesis. Finally, we conduct cell viability assay to determine the toxicity of Aβ oligomers formed on membranes. Overall, by uncovering the roles of GM1 in mediating early Aβ oligomer formation and maintenance, our work provides a novel direction for pharmaceutical research for AD.
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