PFN1 and amyotrophic lateral sclerosis: Several mutations in Profilin1 (PFN1), an actin-binding protein involved in actin cytoskeleton dynamics, have been identified in ALS [78,79], and mutant PFN1 has been shown to alter the distribution of RNA-binding proteins such as TARDBP, FUS, FMRP, and SMN, and disrupt the post-transcriptional regulation of their target mRNAs [80].