학술논문

Cytosolic Trapping of a Mitochondrial Heat Shock Protein Is an Early Pathological Event in Synucleinopathies
Document Type
Source
Cell Reports MultiPark: Multidisciplinary research focused on Parkinson´s disease. 28(1):6-77
Subject
alpha-synuclein
HSP10
mitochondria
Parkinson's disease
proteostasis
striatum
synaptosome
Medicin och hälsovetenskap
Medicinska och farmaceutiska grundvetenskaper
Cell- och molekylärbiologi
Medical and Health Sciences
Basic Medicine
Cell and Molecular Biology
Language
English
ISSN
2211-1247
Abstract
Alpha-synuclein (aSyn) accumulates in intracellular inclusions in synucleinopathies, but the molecular mechanisms leading to disease are unclear. We identify the 10 kDa heat shock protein (HSP10) as a mediator of aSyn-induced mitochondrial impairments in striatal synaptosomes. We find an age-associated increase in the cytosolic levels of HSP10, and a concomitant decrease in the mitochondrial levels, in aSyn transgenic mice. The levels of superoxide dismutase 2, a client of the HSP10/HSP60 folding complex, and synaptosomal spare respiratory capacity are also reduced. Overexpression of HSP10 ameliorates aSyn-associated mitochondrial dysfunction and delays aSyn pathology in vitro and in vivo. Altogether, our data indicate that increased levels of aSyn induce mitochondrial deficits, at least partially, by sequestering HSP10 in the cytosol and preventing it from acting in mitochondria. Importantly, these alterations manifest first at presynaptic terminals. Our study not only provides mechanistic insight into synucleinopathies but opens new avenues for targeting underlying cellular pathologies. Szegő et al. identify HSP10 as a modulator of alpha-synuclein-induced mitochondrial impairment in striatal synaptosomes. Age-associated increase in the cytosolic and decrease in mitochondrial levels of HSP10 results in a reduction in the levels of SOD2 and of synaptosomal ATP production on demand. HSP10 overexpression delays alpha-synuclein pathology both in vitro and in vivo.