TLR4 and amyotrophic lateral sclerosis: In a fly model of amyotrophic lateral sclerosis (ALS), a devastating and rapidly progressing neurodegenerative condition, motorneuron-specific overexpression of the ALS-related RNA-binding protein 43-kDa TAR DNA-binding protein (TDP-43) leads to dose-dependent increase in expression of Toll pathway-related AMP genes including drosomycin and defensin in head tissue [71].