Moreover, splicing defects could also determine alterations in the microtubule-based motor proteins (kinesin and dynein) and other interacting proteins, justifying the well-known alteration of cellular trafficking in SMA (Dale et al., 2011): notably, dynein can affect the expression and the clustering of agrin-induced AChRs, MuSK and Rapsyn; in addition defects in dynein can lead to impairment of NMJs, and seem to be involved in ALS neurodegeneration (Vilmont et al., 2016). Here, RAPSN is linked to proximal spinal muscular atrophy.