ZFIN ID: ZDB-PUB-180627-10
Nucleo-cytoplasmic transport of TDP-43 studied in real time: impaired microglia function leads to axonal spreading of TDP-43 in degenerating motor neurons
Svahn, A.J., Don, E.K., Badrock, A.P., Cole, N.J., Graeber, M.B., Yerbury, J.J., Chung, R., Morsch, M.
Date: 2018
Source: Acta Neuropathologica   136(3): 445-459 (Journal)
Registered Authors: Badrock, Andrew P., Chung, Roger, Cole, Nicholas, Don, Emily, Morsch, Marco, Svahn, Adam
Keywords: Amyotrophic lateral sclerosis (ALS), Microglia, Motor neuron disease (MND), Neurodegeneration, Pathological spreading, TDP-43, Zebrafish
MeSH Terms:
  • Animals
  • Axons/metabolism*
  • Axons/pathology
  • DNA-Binding Proteins/metabolism*
  • Microglia/metabolism*
  • Microglia/pathology
  • Motor Neurons/metabolism*
  • Motor Neurons/pathology
  • Nerve Degeneration/metabolism*
  • Nerve Degeneration/pathology
  • Protein Transport
  • Zebrafish
  • Zebrafish Proteins/metabolism*
PubMed: 29943193 Full text @ Acta Neuropathol.
Transactivating DNA-binding protein-43 (TDP-43) deposits represent a typical finding in almost all ALS patients, more than half of FTLD patients and patients with several other neurodegenerative disorders. It appears that perturbation of nucleo-cytoplasmic transport is an important event in these conditions but the mechanistic role and the fate of TDP-43 during neuronal degeneration remain elusive. We have developed an experimental system for visualising the perturbed nucleocytoplasmic transport of neuronal TDP-43 at the single-cell level in vivo using zebrafish spinal cord. This approach enabled us to image TDP-43-expressing motor neurons before and after experimental initiation of cell death. We report the formation of mobile TDP-43 deposits within degenerating motor neurons, which are normally phagocytosed by microglia. However, when microglial cells were depleted, injury-induced motor neuron degeneration follows a characteristic process that includes TDP-43 redistribution into the cytoplasm, axon and extracellular space. This is the first demonstration of perturbed TDP-43 nucleocytoplasmic transport in vivo, and suggests that impairment in microglial phagocytosis of dying neurons may contribute towards the formation of pathological TDP-43 presentations in ALS and FTLD.