Format

Send to

Choose Destination
Hum Mol Genet. 2019 Nov 7. pii: ddz267. doi: 10.1093/hmg/ddz267. [Epub ahead of print]

Sigma-1 receptor is a key genetic modulator in amyotrophic lateral sclerosis.

Author information

1
MMDN, University of Montpellier, INSERM, EPHE, UMR_S1198, Montpellier, France.
2
Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA.
3
MEA, Plateforme Microscopie Electronique et Analytique, University of Montpellier, Montpellier, France.
4
IBMM, University of Montpellier, CNRS, UMR5247, Montpellier, France.

Abstract

Sigma-1 receptor (S1R) is an endoplasmic reticulum (ER) chaperone that regulates mitochondrial respiration but also controls cellular defense against ER and oxidative stress. This makes S1R a potential therapeutic target in amyotrophic lateral sclerosis (ALS). Especially, as a missense mutation E102Q in S1R has been reported in few familial ALS cases. However, the pathogenicity of S1RE102Q and the beneficial impact of S1R in the ALS context remain to be demonstrated in vivo. To address this, we generated transgenic Drosophila that express human wild-type S1R or S1RE102Q. Expression of mutant S1R in fly neurons induces abnormal eye morphology and locomotor defects in a dose-dependent manner. This was accompanied by abnormal mitochondrial fragmentation, reduced ATP levels and a higher fatigability at the neuromuscular junction during high energy demand. Overexpressing IP3 receptor or glucose transporter mitigates the S1RE102Q-induced eye phenotype, further highlighting the role of calcium and energy metabolism in its toxicity. More importantly, we showed that wild-type S1R rescues locomotor activity and ATP levels of flies expressing the key ALS protein, TDP43. Moreover, overexpressing wild-type S1R enhances resistance of flies to oxidative stress. Therefore, our data provide the first genetic evidence that mutant S1R recapitulates ALS pathology in vivo while increasing S1R confers neuroprotection against TDP43 toxicity.

PMID:
31696229
DOI:
10.1093/hmg/ddz267

Supplemental Content

Full text links

Icon for Silverchair Information Systems
Loading ...
Support Center