TDP-43 induces mitochondrial damage and activates the mitochondrial unfolded protein response

PLoS Genet. 2019 May 17;15(5):e1007947. doi: 10.1371/journal.pgen.1007947. eCollection 2019 May.


Mutations in or dys-regulation of the TDP-43 gene have been associated with TDP-43 proteinopathy, a spectrum of neurodegenerative diseases including Frontotemporal Lobar Degeneration (FTLD) and Amyotrophic Lateral Sclerosis (ALS). The underlying molecular and cellular defects, however, remain unclear. Here, we report a systematic study combining analyses of patient brain samples with cellular and animal models for TDP-43 proteinopathy. Electron microscopy (EM) analyses of patient samples revealed prominent mitochondrial impairment, including abnormal cristae and a loss of cristae; these ultrastructural changes were consistently observed in both cellular and animal models of TDP-43 proteinopathy. In these models, increased TDP-43 expression induced mitochondrial dysfunction, including decreased mitochondrial membrane potential and elevated production of reactive oxygen species (ROS). TDP-43 expression suppressed mitochondrial complex I activity and reduced mitochondrial ATP synthesis. Importantly, TDP-43 activated the mitochondrial unfolded protein response (UPRmt) in both cellular and animal models. Down-regulating mitochondrial protease LonP1 increased mitochondrial TDP-43 levels and exacerbated TDP-43-induced mitochondrial damage as well as neurodegeneration. Together, our results demonstrate that TDP-43 induced mitochondrial impairment is a critical aspect in TDP-43 proteinopathy. Our work has not only uncovered a previously unknown role of LonP1 in regulating mitochondrial TDP-43 levels, but also advanced our understanding of the pathogenic mechanisms for TDP-43 proteinopathy. Our study suggests that blocking or reversing mitochondrial damage may provide a potential therapeutic approach to these devastating diseases.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP-Dependent Proteases / genetics*
  • ATP-Dependent Proteases / metabolism
  • Adenosine Triphosphate / biosynthesis
  • Amyotrophic Lateral Sclerosis / genetics*
  • Amyotrophic Lateral Sclerosis / metabolism
  • Amyotrophic Lateral Sclerosis / pathology
  • Animals
  • Brain / metabolism
  • Brain / pathology
  • DNA-Binding Proteins / genetics*
  • DNA-Binding Proteins / metabolism
  • Disease Models, Animal
  • Drosophila melanogaster
  • Electron Transport Complex I / genetics
  • Electron Transport Complex I / metabolism
  • Frontotemporal Lobar Degeneration / genetics*
  • Frontotemporal Lobar Degeneration / metabolism
  • Frontotemporal Lobar Degeneration / pathology
  • Gene Expression Regulation
  • HEK293 Cells
  • Humans
  • Membrane Potential, Mitochondrial / genetics
  • Mitochondria / metabolism
  • Mitochondria / pathology
  • Mitochondrial Proteins / genetics*
  • Mitochondrial Proteins / metabolism
  • Mutation
  • Reactive Oxygen Species / metabolism
  • Signal Transduction
  • TDP-43 Proteinopathies / genetics*
  • TDP-43 Proteinopathies / metabolism
  • TDP-43 Proteinopathies / pathology
  • Unfolded Protein Response*


  • DNA-Binding Proteins
  • Mitochondrial Proteins
  • Reactive Oxygen Species
  • TARDBP protein, human
  • Adenosine Triphosphate
  • ATP-Dependent Proteases
  • LONP1 protein, human
  • Electron Transport Complex I