TY - JOUR
T1 - Serine 129 phosphorylation of α-synuclein induces unfolded protein response-mediated cell death
AU - Sugeno, Naoto
AU - Takeda, Atsushi
AU - Hasegawa, Takafumi
AU - Kobayashi, Michiko
AU - Kikuchi, Akio
AU - Mori, Fumiaki
AU - Wakabayashi, Koichi
AU - Itoyama, Yasuto
PY - 2008/8/22
Y1 - 2008/8/22
N2 - α-Synuclein is a major protein component deposited in Lewy bodies and Lewy neurites that is extensively phosphorylated at Ser129, although its role in neuronal degeneration is still elusive. In this study, several apoptotic pathways were examined in α-synuclein-overexpressing SH-SY5Y cells. Following the treatment with rotenone, a mitochondrial complex I inhibitor, wild type α-synuclein-overexpressing cells demonstrated intracellular aggregations, which shared a number of features with Lewy bodies, although cells overexpressing the S129A mutant, in which phosphorylation at Ser129 was blocked, showed few aggregations. In wild type α-synuclein cells treated with rotenone, the proportion of phosphorylated α-synuclein was about 1.6 times higher than that of untreated cells. Moreover, induction of unfolded protein response (UPR) markers was evident several hours before the induction of mitochondrial disruption and caspase-3 activation. Eukaryotic initiation factor 2α, a member of the PERK pathway family, was remarkably activated at early phases. On the other hand, the S129A mutant failed to activate UPR. Casein kinase 2 inhibitor, which decreased α-synuclein phosphorylation, also reduced UPR activation. The α-synuclein aggregations were colocalized with a marker for the endoplasmic reticulum-Golgi intermediate compartment. Taken together, it seems plausible that α-synuclein toxicity is dependent on the phosphorylation at Ser129 that induces the UPRs, possibly triggered by the disturbed endoplasmic reticulum-Golgi trafficking.
AB - α-Synuclein is a major protein component deposited in Lewy bodies and Lewy neurites that is extensively phosphorylated at Ser129, although its role in neuronal degeneration is still elusive. In this study, several apoptotic pathways were examined in α-synuclein-overexpressing SH-SY5Y cells. Following the treatment with rotenone, a mitochondrial complex I inhibitor, wild type α-synuclein-overexpressing cells demonstrated intracellular aggregations, which shared a number of features with Lewy bodies, although cells overexpressing the S129A mutant, in which phosphorylation at Ser129 was blocked, showed few aggregations. In wild type α-synuclein cells treated with rotenone, the proportion of phosphorylated α-synuclein was about 1.6 times higher than that of untreated cells. Moreover, induction of unfolded protein response (UPR) markers was evident several hours before the induction of mitochondrial disruption and caspase-3 activation. Eukaryotic initiation factor 2α, a member of the PERK pathway family, was remarkably activated at early phases. On the other hand, the S129A mutant failed to activate UPR. Casein kinase 2 inhibitor, which decreased α-synuclein phosphorylation, also reduced UPR activation. The α-synuclein aggregations were colocalized with a marker for the endoplasmic reticulum-Golgi intermediate compartment. Taken together, it seems plausible that α-synuclein toxicity is dependent on the phosphorylation at Ser129 that induces the UPRs, possibly triggered by the disturbed endoplasmic reticulum-Golgi trafficking.
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U2 - 10.1074/jbc.M802223200
DO - 10.1074/jbc.M802223200
M3 - Article
C2 - 18562315
AN - SCOPUS:53149133169
VL - 283
SP - 23179
EP - 23188
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 34
ER -