1. Cell Biology
  2. Neuroscience
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Dendritic mitochondria reach stable positions during circuit development

  1. Michelle C Faits
  2. Chunmeng Zhang
  3. Florentina Soto
  4. Daniel Kerschensteiner  Is a corresponding author
  1. Washington University School of Medicine, United States
Research Article
  • Cited 44
  • Views 3,580
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Cite this article as: eLife 2016;5:e11583 doi: 10.7554/eLife.11583

Abstract

Mitochondria move throughout neuronal dendrites and localize to sites of energy demand. The prevailing view of dendritic mitochondria as highly motile organelles whose distribution is continually adjusted by neuronal activity via Ca2+-dependent arrests is based on observations in cultured neurons exposed to artificial stimuli. Here, we analyze the movements of mitochondria in ganglion cell dendrites in the intact retina. We find that whereas during development 30% of mitochondria are motile at any time, as dendrites mature, mitochondria all but stop moving and localize stably to synapses and branch points. Neither spontaneous nor sensory-evoked activity and Ca2+ transients alter motility of dendritic mitochondria; and pathological hyperactivity in a mouse model of retinal degeneration elevates rather than reduces motility. Thus, our findings indicate that dendritic mitochondria reach stable positions during a critical developmental period of high motility, and challenge current views about the role of activity in regulating mitochondrial transport in dendrites.

Article and author information

Author details

  1. Michelle C Faits

    Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Saint Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Chunmeng Zhang

    Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Florentina Soto

    Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Daniel Kerschensteiner

    Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, United States
    For correspondence
    dkerschensteiner@wustl.edu
    Competing interests
    The authors declare that no competing interests exist.

Ethics

Animal experimentation: All animals were handled according to protocols approved by the Animal Studies Committee of Washington University School of Medicine (Protocol#: 20140095) and experiments were performed in compliance with the National Institutes of Health Guide for the Care and Use of Laboratory Animals.

Reviewing Editor

  1. Richard J Youle, National Institute of Neurological Disorders and Stroke, National Institutes of Health, United States

Publication history

  1. Received: September 14, 2015
  2. Accepted: December 30, 2015
  3. Accepted Manuscript published: January 7, 2016 (version 1)
  4. Version of Record published: January 28, 2016 (version 2)

Copyright

© 2016, Faits et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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