GRN and amyotrophic lateral sclerosis: This is perhaps surprising given the abundant expression of PGRN in murine MNs, its ability to regulate neurite extension and survival in murine MN cells in culture [29,30], the association of GRN mutations with amyotrophic lateral sclerosis as a putative susceptibility factor [45] and the results obtained in the zebrafish model reported in the present study.