title: Dendritic mitochondria reach stable positions during circuit development.
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 Ca(2+)-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 Ca(2+) 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.
authors.affiliation: Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Saint Louis, United States.|Graduate Program in Developmental, Regenerative and Stem Cell Biology, Washington University School of Medicine, St. Louis, United States.
authors.forename: Michelle C
authors.initials: MC
authors.lastname: Faits
authors.affiliation: Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Saint Louis, United States.
authors.forename: Chunmeng
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Saint Louis, United States.
authors.forename: Florentina
authors.initials: F
authors.lastname: Soto
authors.affiliation: Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Saint Louis, United States.|Department of Neuroscience, Washington University School of Medicine, Saint Louis, United States.|Department of Biomedical Engineering, Washington University School of Medicine, Saint Louis, United States.|Hope Center for Neurological Disorders, Washington University School of Medicine, Saint Louis, United States.
authors.forename: Daniel
authors.initials: D
authors.lastname: Kerschensteiner
mesh_terms: D000818:Animals; D003712:Dendrites / Q000502:physiology*; D008124:Locomotion; D008810:Mice, Inbred C57BL; D008928:Mitochondria / Q000502:physiology*; D012165:Retinal Ganglion Cells / Q000502:physiology*
keywords: cell biology; dendrites; mitochondria; mouse; neuron; neuroscience; retinal circuitry