The multifaceted role of kinases in amyotrophic lateral sclerosis: genetic, pathological and therapeutic implications

Amyotrophic lateral sclerosis is the most common degenerative disorder of motor neurons in adults. As there is no cure, thousands of individuals who are alive at present will succumb to the disease. In recent years, numerous causative genes and risk factors for amyotrophic lateral sclerosis have been identified. Several of the recently identified genes encode kinases. In addition, the hypothesis that (de)phosphorylation processes drive the disease process resulting in selective motor neuron degeneration in different disease variants has been postulated. We re-evaluate the evidence for this hypothesis based on recent findings and discuss the multiple roles of kinases in amyotrophic lateral sclerosis pathogenesis. We propose that kinases could represent promising therapeutic targets. Mainly due to the comprehensive regulation of kinases, however, a better understanding of the disturbances in the kinome network in amyotrophic lateral sclerosis is needed to properly target specific kinases in the clinic.

Loss of TP73 function contributes to amyotrophic lateral sclerosis pathogenesis

Much remains unknown about the genetics and pathophysiology underlying the neurodegenerative disease amyotrophic lateral sclerosis (ALS). We analyzed exome sequences from a cohort of 87 sporadic ALS (SALS) patients and 324 healthy individuals. TP73, a homolog of the TP53 tumor suppressor gene, had five rare deleterious protein-coding variants; in a separate collection of >2,900 ALS patients we identified an additional 19 rare deleterious variants in TP73. An in vitro C2C12 myoblast growth assay confirmed that these variants impair or alter TP73 function. In vivo mutagenesis of zebrafish tp73 using CRISPR led to impaired motor neuron development and abnormal axonal morphology, concordant with ALS pathology. Together, these results demonstrate that TP73 is a risk factor for ALS, and identifies a novel dysfunctional cellular process in the pathogenesis of ALS.