title: Treatment with a Global Methyltransferase Inhibitor Induces the Intranuclear Aggregation of ALS-Linked FUS Mutant In Vitro.
abstract: FUS/TLS (fused in sarcoma/translocated in liposarcoma) encodes a multifunctional DNA/RNA binding protein with non-classical carboxy (C)-terminal nuclear localization signal (NLS). A variety of ALS-linked mutations are clustered in the C-terminal NLS, resulting in the cytoplasmic mislocalization and aggregation. Since the arginine methylations are implicated in the nuclear-cytoplasmic shuttling of FUS, a methylation inhibitor could be one of therapeutic targets for FUS-linked ALS. We here examined effects of methylation inhibitors on the cytoplasmic mislocalization and aggregates of ALS-linked C-terminal FUS mutant in a cell culture system. Treatment with adenosine dialdehyde (AdOx), a representative global methyltransferase inhibitor, remarkably mitigated the cytoplasmic mislocalization and aggregation of FUS mutant, which is consistent with previous reports. However, AdOx treatment of higher concentration and longer time period evoked the intranuclear aggregation of the ectopic expressed FUS protein. The pull down assay and the morphological analysis indicated the binding between FUS and Transportin could be potentiated by AdOx treatment through modulating methylation status in RGG domains of FUS. These findings indicated the treatment with a methylation inhibitor at the appropriate levels could alleviate the cytoplasmic mislocalization but in excess this could cause the intranuclear aggregation of FUS C-terminal mutant.
authors.affiliation: Department of Neurobiology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-8670, Japan.
authors.forename: Sakiko
authors.initials: S
authors.lastname: Fujii
authors.affiliation: Department of Neurobiology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-8670, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Takanashi
authors.affiliation: Department of Neurobiology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-8670, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Kitajo
authors.affiliation: Department of Neurobiology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-8670, Japan. atsyama@restaff.chiba-u.jp.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Yamaguchi
mesh_terms: D000241:Adenosine / Q000031:analogs & derivatives* / Q000494:pharmacology; D000690:Amyotrophic Lateral Sclerosis / Q000235:genetics*; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000378:metabolism*; D057809:HEK293 Cells; D006801:Humans; D008745:Methylation; D008780:Methyltransferases / Q000037:antagonists & inhibitors*; D009154:Mutation; D066329:Protein Aggregates; D034702:RNA-Binding Protein FUS / Q000235:genetics / Q000378:metabolism*; D013347:Subcellular Fractions / Q000378:metabolism; D013997:Time Factors
chemical_list: C000599550:FUS protein, human; D066329:Protein Aggregates; D034702:RNA-Binding Protein FUS; C027579:periodate-oxidized adenosine; D008780:Methyltransferases; D000241:Adenosine
keywords: ALS; Aggregation; Arginine methylation; FUS