FMR1 and nervous system disorder: Here, we show that HuD overexpression, in otherwise normal MNs, produces changes strikingly similar to those observed in mutant FUS MNs on the expression of a set of genes that are: (a) involved in nervous system diseases; (b) targets of wild-type FUS in intronic regions; (c) targets of mutant FUS in the 3′UTR; (d) targets of FMRP; (e) involved in synaptic transmission and neuron development.