title: Rapamycin alleviates pathogenesis of a new Drosophila model of ALS-TDP.
abstract: TDP-43 is a multi-functional RNA/DNA-binding protein, well-conserved among many species including mammals and Drosophila. However, it is also a major component of the pathological inclusions associated with degenerating motor neurons of amyotrophic lateral sclerosis (ALS). Further, TDP-43 is a signature protein in one subtype of frontotemporal degeneration, FTLD-U. Currently, there are no effective drugs for these neurodegenerative diseases. We describe the generation and characterization of a new fly model of ALS-TDP with transgenic expression of the Drosophila ortholog of TDP-43, dTDP, in adult flies under the control of a temperature-sensitive motor neuron-specific GAL4, thus bypassing the deleterious effect of dTDP during development. Diminished lifespan as well as impaired locomotor activities of the flies following induction of dTDP overexpression have been observed. Dissection of the T1/T2 region of the thoracic ganglia has revealed loss of these neurons. To counter the defects in this fly model of ALS-TDP, we have examined the therapeutic effects of the autophagy activator, rapamycin. Although harmful to the control flies, administration of 400 μM rapamycin before the induction of dTDP overexpression can significantly reduce the number of neurons bearing dTDP (+) aggregates, as well as partially rescue the diminished lifespan and locomotive defects of the ALS-TDP flies. Furthermore, we identify S6K, a downstream mediator of the TOR pathway, as one genetic modifier of dTDP. In sum, this Drosophila model of ALS-TDP under temporal and spatial control presents a useful new genetic tool for the screening and validation of therapeutic drugs for ALS. Furthermore, the data support our previous finding that autophagy activators including rapamycin are potential therapeutic drugs for the progression of neurodegenerative diseases with TDP-43 proteinopathies.
authors.affiliation: a Institute of Molecular Medicine, College of Medicine, National Taiwan University , Taipei , Taiwan.|b Institute of Molecular Biology, Academia Sinica , Taipei , Taiwan.
authors.forename: Ching-Wei
authors.initials: CW
authors.lastname: Cheng
authors.affiliation: b Institute of Molecular Biology, Academia Sinica , Taipei , Taiwan.
authors.forename: Meng-Jau
authors.initials: MJ
authors.lastname: Lin
authors.affiliation: a Institute of Molecular Medicine, College of Medicine, National Taiwan University , Taipei , Taiwan.|b Institute of Molecular Biology, Academia Sinica , Taipei , Taiwan.
authors.forename: Che-Kun James
authors.initials: CK
authors.lastname: Shen
mesh_terms: D000690:Amyotrophic Lateral Sclerosis / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism; D000818:Animals; D030801:Animals, Genetically Modified; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004195:Disease Models, Animal; D004331:Drosophila melanogaster; D009043:Motor Activity / Q000187:drug effects* / Q000235:genetics; D009154:Mutation; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D020123:Sirolimus / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D004268:DNA-Binding Proteins; D020123:Sirolimus
keywords: Amyotrophic lateral sclerosis; D42ts-GAL4; Drosophila; TDP-43; lifespan; locomotor activity