A High-Content Screen Identifies TPP1 and Aurora B as Regulators of Axonal Mitochondrial Transport

Cell Rep. 2019 Sep 17;28(12):3224-3237.e5. doi: 10.1016/j.celrep.2019.08.035.

Abstract

Dysregulated axonal trafficking of mitochondria is linked to neurodegenerative disorders. We report a high-content screen for small-molecule regulators of the axonal transport of mitochondria. Six compounds enhanced mitochondrial transport in the sub-micromolar range, acting via three cellular targets: F-actin, Tripeptidyl peptidase 1 (TPP1), or Aurora Kinase B (AurKB). Pharmacological inhibition or small hairpin RNA (shRNA) knockdown of each target promotes mitochondrial axonal transport in rat hippocampal neurons and induced pluripotent stem cell (iPSC)-derived human cortical neurons and enhances mitochondrial transport in iPSC-derived motor neurons from an amyotrophic lateral sclerosis (ALS) patient bearing one copy of SOD1A4V mutation. Our work identifies druggable regulators of axonal transport of mitochondria, provides broadly applicable methods for similar image-based screens, and suggests that restoration of proper axonal trafficking of mitochondria can be achieved in human ALS neurons.

Keywords: ALS; Aurora B; F-actin; TPP1; axonal transport; high-content screening; mitochondria.

MeSH terms

  • Aminopeptidases / genetics
  • Aminopeptidases / metabolism*
  • Amyotrophic Lateral Sclerosis / genetics
  • Amyotrophic Lateral Sclerosis / metabolism*
  • Amyotrophic Lateral Sclerosis / pathology
  • Animals
  • Aurora Kinase B / genetics
  • Aurora Kinase B / metabolism*
  • Axons / metabolism*
  • Axons / pathology
  • Biological Transport, Active
  • Dipeptidyl-Peptidases and Tripeptidyl-Peptidases / genetics
  • Dipeptidyl-Peptidases and Tripeptidyl-Peptidases / metabolism*
  • Female
  • HEK293 Cells
  • Hippocampus / metabolism*
  • Hippocampus / pathology
  • Humans
  • Mice
  • Mice, Knockout
  • Mitochondria / genetics
  • Mitochondria / metabolism*
  • Mitochondria / pathology
  • Rats
  • Rats, Sprague-Dawley
  • Serine Proteases / genetics
  • Serine Proteases / metabolism*
  • Superoxide Dismutase-1 / genetics
  • Superoxide Dismutase-1 / metabolism
  • Tripeptidyl-Peptidase 1

Substances

  • SOD1 protein, human
  • Tpp1 protein, mouse
  • Tpp1 protein, rat
  • Tripeptidyl-Peptidase 1
  • Sod1 protein, rat
  • Superoxide Dismutase-1
  • AURKB protein, human
  • Aurkb protein, mouse
  • Aurkb protein, rat
  • Aurora Kinase B
  • Serine Proteases
  • Aminopeptidases
  • Dipeptidyl-Peptidases and Tripeptidyl-Peptidases
  • TPP1 protein, human