FUS and amyotrophic lateral sclerosis: Yeast also has the same PY-type nuclear localization system as FUS but deviations in the recognition signal results in the mentioned cytoplasmic mislocalization of FUS in yeast, i.e., both ALS-linked mutant FUS and full-length FUS mislocalize to the cytoplasm and are equally toxic in yeast due to a non-functional NLS (Ju et al., 2011).