An age-related reduction of brain TBPH/TDP-43 levels precedes the onset of locomotion defects in a Drosophila ALS model

Neuroscience. 2015 Dec 17:311:415-21. doi: 10.1016/j.neuroscience.2015.10.037. Epub 2015 Oct 27.

Abstract

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease. The average age of onset of both sporadic and familial cases is 50-60 years of age. The presence of cytoplasmic inclusions of the RNA-binding protein TAR DNA-binding protein-43 (TDP-43) in the affected neurons is seen in 95% of the ALS cases, which results in TDP-43 nuclear clearance and loss of function. The Drosophila melanogaster ortholog of TDP-43 (TBPH) shares many characteristics with the human protein. Using a TDP-43 aggregation inducer previously developed in human cells, we created a transgenic fly that shows an adult locomotive defect. Phenotype onset correlates with a physiologically age-related drop of TDP-43/TBPH mRNA and protein levels, seen both in mice and flies. Artificial reduction of mRNA levels, in vivo, anticipates the locomotion defect to the larval stage. Our study links, for the first time, aggregation and the age-related, evolutionary conserved reduction of TDP-43/TBPH levels with the onset of an ALS-like locomotion defect in a Drosophila model. A similar process might trigger the human disease.

Keywords: ALS; Drosophila; TDP-43/TBPH levels; aggregation.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aging / metabolism*
  • Amyotrophic Lateral Sclerosis / physiopathology*
  • Animals
  • Animals, Genetically Modified
  • Brain / metabolism
  • DNA-Binding Proteins / deficiency*
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Disease Models, Animal
  • Drosophila Proteins / deficiency*
  • Drosophila Proteins / genetics
  • Drosophila melanogaster
  • Locomotion / physiology
  • Mice
  • RNA Interference
  • RNA, Messenger / metabolism
  • Species Specificity

Substances

  • DNA-Binding Proteins
  • Drosophila Proteins
  • RNA, Messenger
  • TBPH protein, Drosophila
  • TDP-43 protein, mouse