Calpain-Mediated Degradation of Drebrin by Excitotoxicity In vitro and In vivo.

The level of drebrin, an evolutionarily conserved f-actin-binding protein that regulates synaptic structure and function, is reduced in the brains of patients with chronic neurodegenerative diseases such as Alzheimer's disease (AD) and Down's syndrome (DS). It was suggested that excitotoxi...

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Main Authors: Takahiko Chimura, Thomas Launey, Nobuaki Yoshida
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2015-01-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC4408054?pdf=render
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author Takahiko Chimura
Thomas Launey
Nobuaki Yoshida
author_facet Takahiko Chimura
Thomas Launey
Nobuaki Yoshida
author_sort Takahiko Chimura
collection DOAJ
description The level of drebrin, an evolutionarily conserved f-actin-binding protein that regulates synaptic structure and function, is reduced in the brains of patients with chronic neurodegenerative diseases such as Alzheimer's disease (AD) and Down's syndrome (DS). It was suggested that excitotoxic neuronal death caused by overactivation of NMDA-type glutamate receptors (NMDARs) occurs in AD and DS; however, the relationship between excitotoxicity and drebrin loss is unknown. Here, we show that drebrin is a novel target of calpain-mediated proteolysis under excitotoxic conditions induced by the overactivation of NMDARs. In cultured rodent neurons, degradation of drebrin was confirmed by the detection of proteolytic fragments, as well as a reduction in the amount of full-length drebrin. Notably, the NMDA-induced degradation of drebrin in mature neurons occurred concomitantly with a loss of f-actin. Furthermore, pharmacological inhibition of f-actin loss facilitated the drebrin degradation, suggesting a functional linkage between f-actin and drebrin degradation. Biochemical analyses using purified drebrin and calpain revealed that calpain degraded drebrin directly in vitro. Furthermore, cerebral ischemia also induced the degradation of drebrin in vivo. These findings suggest that calpain-mediated degradation of drebrin is a fundamental pathology of neurodegenerative diseases mediated by excitotoxicity, regardless of whether they are acute or chronic. Drebrin regulates the synaptic clustering of NMDARs; therefore, degradation of drebrin under excitotoxic conditions may modulate NMDAR-mediated signal transductions, including pro-survival signaling. Overall, the results presented here provide novel insights into the molecular basis of cellular responses to excitotoxicity in vitro and in vivo.
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spelling doaj.art-594b91d7c16a4073b07277f2f36d3ad22022-12-22T02:35:59ZengPublic Library of Science (PLoS)PLoS ONE1932-62032015-01-01104e012511910.1371/journal.pone.0125119Calpain-Mediated Degradation of Drebrin by Excitotoxicity In vitro and In vivo.Takahiko ChimuraThomas LauneyNobuaki YoshidaThe level of drebrin, an evolutionarily conserved f-actin-binding protein that regulates synaptic structure and function, is reduced in the brains of patients with chronic neurodegenerative diseases such as Alzheimer's disease (AD) and Down's syndrome (DS). It was suggested that excitotoxic neuronal death caused by overactivation of NMDA-type glutamate receptors (NMDARs) occurs in AD and DS; however, the relationship between excitotoxicity and drebrin loss is unknown. Here, we show that drebrin is a novel target of calpain-mediated proteolysis under excitotoxic conditions induced by the overactivation of NMDARs. In cultured rodent neurons, degradation of drebrin was confirmed by the detection of proteolytic fragments, as well as a reduction in the amount of full-length drebrin. Notably, the NMDA-induced degradation of drebrin in mature neurons occurred concomitantly with a loss of f-actin. Furthermore, pharmacological inhibition of f-actin loss facilitated the drebrin degradation, suggesting a functional linkage between f-actin and drebrin degradation. Biochemical analyses using purified drebrin and calpain revealed that calpain degraded drebrin directly in vitro. Furthermore, cerebral ischemia also induced the degradation of drebrin in vivo. These findings suggest that calpain-mediated degradation of drebrin is a fundamental pathology of neurodegenerative diseases mediated by excitotoxicity, regardless of whether they are acute or chronic. Drebrin regulates the synaptic clustering of NMDARs; therefore, degradation of drebrin under excitotoxic conditions may modulate NMDAR-mediated signal transductions, including pro-survival signaling. Overall, the results presented here provide novel insights into the molecular basis of cellular responses to excitotoxicity in vitro and in vivo.http://europepmc.org/articles/PMC4408054?pdf=render
spellingShingle Takahiko Chimura
Thomas Launey
Nobuaki Yoshida
Calpain-Mediated Degradation of Drebrin by Excitotoxicity In vitro and In vivo.
PLoS ONE
title Calpain-Mediated Degradation of Drebrin by Excitotoxicity In vitro and In vivo.
title_full Calpain-Mediated Degradation of Drebrin by Excitotoxicity In vitro and In vivo.
title_fullStr Calpain-Mediated Degradation of Drebrin by Excitotoxicity In vitro and In vivo.
title_full_unstemmed Calpain-Mediated Degradation of Drebrin by Excitotoxicity In vitro and In vivo.
title_short Calpain-Mediated Degradation of Drebrin by Excitotoxicity In vitro and In vivo.
title_sort calpain mediated degradation of drebrin by excitotoxicity in vitro and in vivo
url http://europepmc.org/articles/PMC4408054?pdf=render
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AT thomaslauney calpainmediateddegradationofdrebrinbyexcitotoxicityinvitroandinvivo
AT nobuakiyoshida calpainmediateddegradationofdrebrinbyexcitotoxicityinvitroandinvivo