Related Experiment Video

Updated: Oct 2, 2026

Modeling Charcot-Marie-Tooth Disease In Vitro by Transfecting Mouse Primary Motoneurons
07:43

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Published on: January 7, 2019

Mutant Cu, Zn superoxide dismutase that causes motoneuron degeneration is present in mitochondria in the CNS

Cynthia M J Higgins1, Cheolwha Jung, Hongliu Ding

  • 1Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA.

The Journal of Neuroscience : the Official Journal of the Society for Neuroscience
|March 12, 2002
PubMed

Insights

Mutations in copper, zinc superoxide dismutase (SOD1) are linked to amyotrophic lateral sclerosis (ALS). This study reveals SOD1 is present within mitochondria in the central nervous system, suggesting a direct role in neurodegeneration.

Area of Science:

  • Neuroscience
  • Cell Biology
  • Genetics

Background:

  • Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease.
  • Mutations in copper, zinc superoxide dismutase (SOD1) are a known cause of familial ALS.
  • Mitochondrial dysfunction is an early event in ALS pathogenesis.

Purpose of the Study:

  • To investigate the intracellular localization of SOD1 in the central nervous system (CNS).
  • To determine if SOD1 is present in mitochondria, where it could directly contribute to neurotoxicity in ALS.

Main Methods:

  • Immunofluorescence confocal microscopy to assess SOD1 localization in mouse spinal cord.
  • Immunoelectron microscopy to confirm SOD1 presence within mitochondria.

Main Results:

  • Endogenous mouse SOD1, wild-type human SOD1, and mutant human SOD1 (G93A) colocalized with mitochondria in the spinal cord.
  • SOD1 was detected within mitochondria at concentrations comparable to the cytoplasm.

Conclusions:

  • SOD1 is not exclusively a cytosolic enzyme but is also localized within mitochondria in the CNS.
  • This mitochondrial localization of SOD1 provides a potential mechanism for its direct role in motoneuron degeneration in ALS.

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