TY - JOUR
T1 - Inflammation kinase PKR phosphorylates α-synuclein and causes α-synuclein-dependent cell death
AU - Reimer, Lasse
AU - Lund, Louise Buur
AU - Betzer, Cristine
AU - Zheng, Jin
AU - Nielsen, Lærke Dalsgaard
AU - Kofoed, Rikke Hahn
AU - Lassen, Louise Berkhoudt
AU - Bølcho, Ulrik
AU - Paludan, Søren Riis
AU - Fog, Karina
AU - Jensen, Poul Henning
N1 - Copyright © 2017. Published by Elsevier Inc.
PY - 2018/5/1
Y1 - 2018/5/1
N2 - Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy comprise a group of neurodegenerative diseases termed synucleinopathies. Synucleinopathie are, characterized by presence of inclusion bodies in degenerating brain cells which contain aggregated α-synuclein phosphorylated on Ser129. Although the inflammation-associated serine-threonine kinase, PKR (EIF2AK2), promotes cellular protection against infection, we demonstrate a pro-degenerative role of activated PKR in an α-synuclein-dependent cell model of multiple system atrophy, where inhibition and silencing of PKR decrease cellular degeneration. In vitro phosphorylation demonstrates that PKR can directly bind and phosphorylate monomeric and filamenteous α-synuclein on Ser129. Inhibition and knockdown of PKR reduce Ser129 phosphorylation in different models (SH-SY5Y ASYN cells, OLN-AS7 cells, primary mouse hippocampal neurons, and acute brain slices), while overexpression of constitutively active PKR increases Ser129 α-syn phosphorylation. Treatment with pre-formed α-synuclein fibrils, proteostatic stress-promoting MG-132 and known PKR activators, herpes simplex virus-1-∆ICP34.5 and LPS, as well as PKR inducer, IFN-β-1b, lead to increased levels of phosphorylated Ser129 α-synuclein that is completely blocked by simultaneous PKR inhibition. These results reveal a direct link between PKR and the phosphorylation and toxicity of α-synuclein, and they support that neuroinflammatory processes play a role in modulating the pathogenicity of α-synuclein.
AB - Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy comprise a group of neurodegenerative diseases termed synucleinopathies. Synucleinopathie are, characterized by presence of inclusion bodies in degenerating brain cells which contain aggregated α-synuclein phosphorylated on Ser129. Although the inflammation-associated serine-threonine kinase, PKR (EIF2AK2), promotes cellular protection against infection, we demonstrate a pro-degenerative role of activated PKR in an α-synuclein-dependent cell model of multiple system atrophy, where inhibition and silencing of PKR decrease cellular degeneration. In vitro phosphorylation demonstrates that PKR can directly bind and phosphorylate monomeric and filamenteous α-synuclein on Ser129. Inhibition and knockdown of PKR reduce Ser129 phosphorylation in different models (SH-SY5Y ASYN cells, OLN-AS7 cells, primary mouse hippocampal neurons, and acute brain slices), while overexpression of constitutively active PKR increases Ser129 α-syn phosphorylation. Treatment with pre-formed α-synuclein fibrils, proteostatic stress-promoting MG-132 and known PKR activators, herpes simplex virus-1-∆ICP34.5 and LPS, as well as PKR inducer, IFN-β-1b, lead to increased levels of phosphorylated Ser129 α-synuclein that is completely blocked by simultaneous PKR inhibition. These results reveal a direct link between PKR and the phosphorylation and toxicity of α-synuclein, and they support that neuroinflammatory processes play a role in modulating the pathogenicity of α-synuclein.
KW - Alpha-Synuclein
KW - Cytotoxicity
KW - EIF2AK2
KW - Neurodegeneration
KW - PKR
KW - Phosphorylation
KW - Synucleinopathies
UR - http://www.scopus.com/inward/record.url?scp=85044018602&partnerID=8YFLogxK
U2 - 10.1016/j.nbd.2018.03.001
DO - 10.1016/j.nbd.2018.03.001
M3 - Journal article
C2 - 29501855
SN - 0969-9961
VL - 115
SP - 17
EP - 28
JO - Neurobiology of Disease
JF - Neurobiology of Disease
ER -