Arginine residues appear to be critical to aberrant phase separation and karyopherin-mediated chaperoning as overexpression of arginine-containing DPRs derived from RAN translated, C9ALS/FTD-related G4C2 repeat RNA, can induce the assembly of stress granules, triggering the co-localization of Ran and karyopherins into these membraneless organelles.187. This evidence concerns the gene RAN and frontotemporal dementia.