C9ORF72-ALS/FTD-associated poly(GR) binds Atp5a1 and compromises mitochondrial function in vivo

Nat Neurosci. 2019 Jun;22(6):851-862. doi: 10.1038/s41593-019-0397-0. Epub 2019 May 13.


The GGGGCC repeat expansion in C9ORF72 is the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). However, it is not known which dysregulated molecular pathways are primarily responsible for disease initiation or progression. We established an inducible mouse model of poly(GR) toxicity in which (GR)80 gradually accumulates in cortical excitatory neurons. Low-level poly(GR) expression induced FTD/ALS-associated synaptic dysfunction and behavioral abnormalities, as well as age-dependent neuronal cell loss, microgliosis and DNA damage, probably caused in part by early defects in mitochondrial function. Poly(GR) bound preferentially to the mitochondrial complex V component ATP5A1 and enhanced its ubiquitination and degradation, consistent with reduced ATP5A1 protein level in both (GR)80 mouse neurons and patient brains. Moreover, inducing ectopic Atp5a1 expression in poly(GR)-expressing neurons or reducing poly(GR) level in adult mice after disease onset rescued poly(GR)-induced neurotoxicity. Thus, poly(GR)-induced mitochondrial defects are a major driver of disease initiation in C9ORF72-related ALS/FTD.

Publication types

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

MeSH terms

  • Amyotrophic Lateral Sclerosis / genetics
  • Amyotrophic Lateral Sclerosis / physiopathology*
  • Animals
  • Brain / metabolism
  • C9orf72 Protein / genetics*
  • DNA Repeat Expansion
  • Disease Models, Animal
  • Frontotemporal Dementia / genetics
  • Frontotemporal Dementia / physiopathology*
  • Humans
  • Mice
  • Mice, Transgenic
  • Mitochondria / pathology*
  • Mitochondrial Proton-Translocating ATPases / metabolism*
  • Neurons / metabolism


  • C9orf72 Protein
  • ATP5A1 protein, mouse
  • ATP5F1A protein, human
  • Mitochondrial Proton-Translocating ATPases

Supplementary concepts

  • Frontotemporal Dementia With Motor Neuron Disease