Dataset Information

USP14 inhibition enhances Parkin-independent mitophagy in iNeurons

ABSTRACT: Loss of proteostasis is well documented during physiological aging and depends on the progressive decline in the activity of two major degradative mechanisms: the ubiquitin-proteasome system (UPS) and the autophagy-lysosomal pathway. This decline in proteostasis is exacerbated in age-associated neurodegenerative diseases, such as Parkinson’s Disease (PD). In PD, patients develop an accumulation of aggregated proteins and dysfunctional mitochondria, which leads to ROS production, neuroinflammation and neurodegeneration. We recently reported that inhibition of the deubiquitinating enzyme USP14, which is known to enhance both the UPS and autophagy, increases lifespan and rescues the pathological phenotype of two Drosophila models of PD. Studies on the effects of USP14 inhibition in mammalian neurons have not yet been conducted. To close this gap, we exploited iNeurons differentiated from human embryonic stem cells (hESCs), and investigated the effect of inhibiting USP14 in these cultured neurons. Quantitative global proteomics analysis performed following genetic ablation or pharmacological inhibition of USP14 demonstrated that USP14 loss of function specifically promotes mitochondrial autophagy in iNeurons. Biochemical and imaging data also showed that USP14 inhibition enhances mitophagy. The mitophagic effect of USP14 inhibition proved to be PINK1/Parkin- independent, instead relying on expression of the mitochondrial E3 Ubiquitin Ligase MITOL/MARCH5. Notably, USP14 inhibition normalized the mitochondrial defects of Parkin KO human neurons.

INSTRUMENT(S): Orbitrap Fusion Lumos

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Neuron, Cell Culture

SUBMITTER: Miguel Prado

LAB HEAD: Miguel Prado

PROVIDER: PXD056511 | Pride | 2024-12-18

REPOSITORIES: Pride

ACCESS DATA

Dataset's files

Source:

			Action	DRS
	479126_a20475_USP14_iNeur_01_TrypLysC_2MC_2mods_MetOx_IAA_TMT_20ppm_0.02.mzid.gz	Mzid
	479127_a20476_USP14_iNeur_02_TrypLysC_2MC_2mods_MetOx_IAA_TMT_20ppm_0.02.mzid.gz	Mzid
	479128_a20477_USP14_iNeur_03_TrypLysC_2MC_2mods_MetOx_IAA_TMT_20ppm_0.02.mzid.gz	Mzid
	479129_a20478_USP14_iNeur_04_TrypLysC_2MC_2mods_MetOx_IAA_TMT_20ppm_0.02.mzid.gz	Mzid
	479130_a20479_USP14_iNeur_05_TrypLysC_2MC_2mods_MetOx_IAA_TMT_20ppm_0.02.mzid.gz	Mzid

Items per page:

1 - 5 of 73

Publications

USP14 inhibition enhances Parkin-independent mitophagy in iNeurons.

Bernardo Greta G Prado Miguel A MA Dashtmian Anna Roshani AR Favaro Mariavittoria M Mauri Sofia S Borsetto Alice A Marchesan Elena E Paulo Joao A JA Gygi Steve P SP Finley Daniel J DJ Ziviani Elena E

Pharmacological research 20241030

Loss of proteostasis is well documented during physiological aging and depends on the progressive decline in the activity of two major degradative mechanisms: the ubiquitin-proteasome system (UPS) and the autophagy-lysosomal pathway. This decline in proteostasis is exacerbated in age-associated neurodegenerative diseases, such as Parkinson's Disease (PD). In PD, patients develop an accumulation of aggregated proteins and dysfunctional mitochondria, which leads to ROS production, neuroinflammatio ...[more]

PMID: 39486496

Similar Datasets

Project description:Mutations in the E3 ubiquitin ligase Parkin cause autosomal recessive Parkinson’s disease. In concert with PINK1, Parkin regulates the clearance of dysfunctional mitochondria via lysosomes. In response, new mitochondria are generated through an interplay of nuclear- and mitochondrial-encoded proteins. Mouse and overexpression models suggests that Parkin also influences these processes, both in the nuclear cascade and at the level of the mitochondrial genome. Additionally, Parkin has been shown to prevent mitochondrial membrane permeation, impeding the escape of mitochondrial DNA (mtDNA). In line with this, serum from Parkin mutation carriers showed higher levels of circulating cell-free mtDNA (ccf-mtDNA) and inflammatory cytokines – a result of the innate immune response - which can be triggered by cytosolic mtDNA. However, Parkin’s relationship with the mitochondrial genome and the mitogenesis pathway has not been explored in patient-derived neurons. To investigate this aspect of Parkin’s cellular function endogenously, we generated induced pluripotent stem cell (iPSC)-derived midbrain neurons from Parkin mutation carriers and healthy controls. In Parkin-deficient cells, several factors in the mitochondrial biogenesis pathway were significantly reduced, resulting in impaired mtDNA homeostasis - a phenomenon that was exacerbated in dopaminergic neurons. Moreover, in response to a lack of freely accessible NAD+, the energy sensor Sirtuin 1, which simultaneously controls mtDNA maintenance processes and mitophagy, was downregulated in Parkin-deficient neurons. However, while impaired lysosomal degradation of mitochondria was only detectable in oxidative conditions, biogenesis defects were already apparent in untreated patient neurons. This may suggest that mitophagy disruption occurs in response to acute stress. By contrast, the biogenesis pathway may be continually impaired in Parkin-associated Parkinson’s disease. Next, using a mutagenic stress model in combination with Parkin knockdown, we detected an increase in ccf-mtDNA and the cytosolic DNA sensor cGAS. To explore if ccf-mtDNA can act as damage-associated molecular pattern in the brain, we used postmortem tissue from a Parkin mutation carrier and performed single-cell RNA sequencing. In the midbrain lacking Parkin, we found a higher percentage of microglia along with an upregulation of proinflammatory cytokines in these cells. Together, our findings suggest a role for Parkin in the control of mitochondrial biogenesis and mtDNA maintenance, which protects midbrain neurons from neuroinflammation-induced degeneration. Future research in iPSC-derived neuron-microglia co-culture systems could aim at developing PD treatment approaches that target the neuronal release or microglial uptake of ccf-mtDNA.