MAPK3 and amyotrophic lateral sclerosis: Second, NEFH is a substrate of the MAP kinases MAPK3 and MAPK1 37 and, phosphorylation of NEFH by stress-activated p38 protein kinases (MAPK11,-12,-14) has been annotated for the amyotrophic lateral sclerosis pathway in Kyoto Encyclopedia of Genes and Genomes indexes 38.