ALS-linked protein disulfide isomerase variants cause motor dysfunction


Disturbance of endoplasmic reticulum (ER) proteostasis is a common feature of amyotrophic lateral sclerosis (ALS). Protein disulfide isomerases (PDIs) are ER foldases identified as possible ALS biomarkers, as well as neuroprotective factors. However, no functional studies have addressed their impact on the disease process. Here, we functionally characterized four ALS”linked mutations recently identified in two major PDI genes, PDIA1 and PDIA3/ERp57. Phenotypic screening in zebrafish revealed that the expression of these PDI variants induce motor defects associated with a disruption of motoneuron connectivity. Similarly, the expression of mutant PDIs impaired dendritic outgrowth in motoneuron cell culture models. Cellular and biochemical studies identified distinct molecular defects underlying the pathogenicity of these PDI mutants. Finally, targeting ERp57 in the nervous system led to severe motor dysfunction in mice associated with a loss of neuromuscular synapses. This study identifies ER proteostasis imbalance as a risk factor for ALS, driving initial stages of the disease

Ute Woehlbier, Alicia Colombo, Mirva J Saaranen, Viviana Pérez, Jorge Ojeda, Fernando J Bustos, Catherine I Andreu, Mauricio Torres, Vicente Valenzuela, Danilo B Medinas, Pablo Rozas, Rene L Vidal, Rodrigo Lopez-Gonzalez, Johnny Salameh, Sara Fernandez-Collemann, Natalia Muñoz, Soledad Matus, Ricardo Armisen, Alfredo Sagredo, Karina Palma, Thergiory Irrazabal, Sandra Almeida, Paloma Gonzalez-Perez, Mario Campero, Fen-Biao Gao, Pablo Henny, Brigitte van Zundert, Lloyd W Ruddock, Miguel L Concha, Juan P Henriquez, Robert H Brown, Claudio Hetz

The EMBO Journal

febrero 11, 2016

DOI: 10.15252/embj.201592224

Investigador BNI: Claudio Hetz , Miguel Concha ,