Protein disulfide isomerase ERp57 protects early muscle denervation in experimental ALS

ABSTRACT: Amyotrophic lateral sclerosis (ALS) is a progressive fatal neurodegenerative disease that affects motoneurons. Mutations in superoxide dismutase 1 (SOD1) have been described as a causative genetic factor for ALS. Mice overexpressing ALS-linked mutant SOD1 develop ALS symptoms accompanied by histopathological alterations and protein aggregation. Protein disulfide isomerase family member ERp57 is one of the main up-regulated proteins in tissue of ALS patients and mutant SOD1 mice, whereas point mutations in ERp57 were described as possible risk factors. ERp57 catalyzes disulfide bond formation and isomerization in the endoplasmic reticulum (ER), constituting a central component of protein quality control mechanisms. However, the actual contribution of ERp57 to ALS pathogenesis remains to be defined. Here, we studied the consequences of overexpressing ERp57 in ALS onset and progression of mutant SOD1G93A mice. The double transgenic SOD1G93A/ERp57WT mice presented improved motor performance, in addition to delayed deterioration of electrophysiological activity of affected muscles compared to single transgenic SOD1G93A littermates at early symptomatic stage. The overexpression of ERp57 reduced mutant SOD1 aggregation, but only at disease end-stage. Instead, the neuroprotective effects of ERp57 were correlated with preserved muscle innervation. Importantly, proteomic analysis revealed that the overexpression of ERp57 increases the levels of synaptic proteins in the spinal cord. Taken together, our results suggest that ERp57 operates as a disease modifier at early stages by maintaining motoneuron connectivity.

INSTRUMENT(S): Orbitrap Exploris 480

ORGANISM(S): Mus Musculus (mouse)

TISSUE(S): Neuron, Nerve Cord

DISEASE(S): Amyotrophic Lateral Sclerosis

SUBMITTER: Madison Wright  

LAB HEAD: Claudio Hetz & Danilo B. Medinas

PROVIDER: PXD023647 | Pride | 2021-02-08

REPOSITORIES: Pride