Localization and mobility of synaptic vesicles in Myosin VI mutants of Drosophila.

BACKGROUND: At the Drosophila neuromuscular junction (NMJ), synaptic vesicles are mobile; however, the mechanisms that regulate vesicle traffic at the nerve terminal are not fully understood. Myosin VI has been shown to be important for proper synaptic physiology and morphology at the NMJ, likely by...

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Main Authors: Marta Kisiel, Kristopher McKenzie, Bryan Stewart
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2014-01-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC4111356?pdf=render
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author Marta Kisiel
Kristopher McKenzie
Bryan Stewart
author_facet Marta Kisiel
Kristopher McKenzie
Bryan Stewart
author_sort Marta Kisiel
collection DOAJ
description BACKGROUND: At the Drosophila neuromuscular junction (NMJ), synaptic vesicles are mobile; however, the mechanisms that regulate vesicle traffic at the nerve terminal are not fully understood. Myosin VI has been shown to be important for proper synaptic physiology and morphology at the NMJ, likely by functioning as a vesicle tether. Here we investigate vesicle dynamics in Myosin VI mutants of Drosophila. RESULTS: In Drosophila, Myosin VI is encoded by the gene, jaguar (jar). To visualize active vesicle cycling we used FM dye loading and compared loss of function alleles of jar with controls. These studies revealed a differential distribution of vesicles at the jar mutant nerve terminal, with the newly endocytosed vesicles observed throughout the mutant boutons in contrast to the peripheral localization visualized at control NMJs. This finding is consistent with a role for Myosin VI in restraining vesicle mobility at the synapse to ensure proper localization. To further investigate regulation of vesicle dynamics by Myosin VI, FRAP analysis was used to analyze movement of GFP-labeled synaptic vesicles within individual boutons. FRAP revealed that synaptic vesicles are moving more freely in the jar mutant boutons, indicated by changes in initial bleach depth and rapid recovery of fluorescence following photobleaching. CONCLUSION: This data provides insights into the role for Myosin VI in mediating synaptic vesicle dynamics at the nerve terminal. We observed mislocalization of actively cycling vesicles and an apparent increase in vesicle mobility when Myosin VI levels are reduced. These observations support the notion that a major function of Myosin VI in the nerve terminal is tethering synaptic vesicles to proper sub-cellular location within the bouton.
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spelling doaj.art-a06f1d00f74641c3ab3a01dd9054ad342022-12-22T01:29:41ZengPublic Library of Science (PLoS)PLoS ONE1932-62032014-01-0197e10298810.1371/journal.pone.0102988Localization and mobility of synaptic vesicles in Myosin VI mutants of Drosophila.Marta KisielKristopher McKenzieBryan StewartBACKGROUND: At the Drosophila neuromuscular junction (NMJ), synaptic vesicles are mobile; however, the mechanisms that regulate vesicle traffic at the nerve terminal are not fully understood. Myosin VI has been shown to be important for proper synaptic physiology and morphology at the NMJ, likely by functioning as a vesicle tether. Here we investigate vesicle dynamics in Myosin VI mutants of Drosophila. RESULTS: In Drosophila, Myosin VI is encoded by the gene, jaguar (jar). To visualize active vesicle cycling we used FM dye loading and compared loss of function alleles of jar with controls. These studies revealed a differential distribution of vesicles at the jar mutant nerve terminal, with the newly endocytosed vesicles observed throughout the mutant boutons in contrast to the peripheral localization visualized at control NMJs. This finding is consistent with a role for Myosin VI in restraining vesicle mobility at the synapse to ensure proper localization. To further investigate regulation of vesicle dynamics by Myosin VI, FRAP analysis was used to analyze movement of GFP-labeled synaptic vesicles within individual boutons. FRAP revealed that synaptic vesicles are moving more freely in the jar mutant boutons, indicated by changes in initial bleach depth and rapid recovery of fluorescence following photobleaching. CONCLUSION: This data provides insights into the role for Myosin VI in mediating synaptic vesicle dynamics at the nerve terminal. We observed mislocalization of actively cycling vesicles and an apparent increase in vesicle mobility when Myosin VI levels are reduced. These observations support the notion that a major function of Myosin VI in the nerve terminal is tethering synaptic vesicles to proper sub-cellular location within the bouton.http://europepmc.org/articles/PMC4111356?pdf=render
spellingShingle Marta Kisiel
Kristopher McKenzie
Bryan Stewart
Localization and mobility of synaptic vesicles in Myosin VI mutants of Drosophila.
PLoS ONE
title Localization and mobility of synaptic vesicles in Myosin VI mutants of Drosophila.
title_full Localization and mobility of synaptic vesicles in Myosin VI mutants of Drosophila.
title_fullStr Localization and mobility of synaptic vesicles in Myosin VI mutants of Drosophila.
title_full_unstemmed Localization and mobility of synaptic vesicles in Myosin VI mutants of Drosophila.
title_short Localization and mobility of synaptic vesicles in Myosin VI mutants of Drosophila.
title_sort localization and mobility of synaptic vesicles in myosin vi mutants of drosophila
url http://europepmc.org/articles/PMC4111356?pdf=render
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AT kristophermckenzie localizationandmobilityofsynapticvesiclesinmyosinvimutantsofdrosophila
AT bryanstewart localizationandmobilityofsynapticvesiclesinmyosinvimutantsofdrosophila