hnRNP R regulates mitochondrial movement and membrane potential in axons of motoneurons

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Sophia Dithmar1, Abdolhossein Zare1, Saeede Salehi1

  • 1Institute of Clinical Neurobiology, University Hospital Wuerzburg, Wuerzburg, Germany.

Neurobiology of Disease
|February 26, 2024
PubMed

Insights

Defects in axonal mitochondria are key to motoneuron diseases. This study reveals that the RNA-binding protein hnRNP R regulates mitochondrial transport and function in motoneuron axons.

Area of Science:

  • Neuroscience
  • Mitochondrial Biology
  • Molecular Biology

Background:

  • Axonal mitochondria defects are early indicators in motoneuron diseases like spinal muscular atrophy and amyotrophic lateral sclerosis.
  • The RNA-binding protein hnRNP R is known to interact with motoneuron disease proteins and plays a role in axonal mRNA transport.

Purpose of the Study:

  • To investigate the role of hnRNP R in the modulation of axonal mitochondria function and transport in motoneurons.

Main Methods:

  • Analysis of axonal mitochondria function and motility in hnRNP R-deficient motoneurons.
  • Assessment of mitochondrial transport dynamics (anterograde and retrograde).
  • Evaluation of respiratory chain complex activity (Complex I and V) and mitochondrial membrane potential.

Main Results:

  • hnRNP R-deficient motoneurons exhibit altered axonal mitochondria function and motility.
  • Mitochondrial transport is impaired, with decreased anterograde and increased retrograde movement.
  • Mitochondrial hyperpolarization occurs due to decreased Complex I and reversed Complex V activity.

Conclusions:

  • hnRNP R plays a crucial role in regulating the transport of axonal mitochondria.
  • hnRNP R is essential for maintaining the functional integrity of mitochondria within motoneuron axons.
  • These findings suggest hnRNP R as a potential therapeutic target for motoneuron disorders.
Keywords:
AxonMitochondriaMotoneuronhnRNP R

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