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Dominant-negative myosin Va impairs retrograde but not anterograde axonal transport of large dense core vesicles.

ABSTRACT: Axonal transport of peptide and hormone-containing large dense core vesicles (LDCVs) is known to be a microtubule-dependent process. Here, we suggest a role for the actin-based motor protein myosin Va specifically in retrograde axonal transport of LDCVs. Using live-cell imaging of transfected hippocampal neurons grown in culture, we measured the speed, transport direction, and the number of LDCVs that were labeled with ectopically expressed neuropeptide Y fused to EGFP. Upon expression of a dominant-negative tail construct of myosin Va, a general reduction of movement in both dendrites and axons was observed. In axons, it was particularly interesting that the retrograde speed of LDCVs was significantly impaired, although anterograde transport remained unchanged. Moreover, particles labeled with the dominant-negative construct often moved in the retrograde direction but rarely in the anterograde direction. We suggest a model where myosin Va acts as an actin-dependent vesicle motor that facilitates retrograde axonal transport.

SUBMITTER: Bittins CM

PROVIDER: S-EPMC3878150 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature

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Dominant-negative myosin Va impairs retrograde but not anterograde axonal transport of large dense core vesicles.

Bittins Claudia Margarethe CM Eichler Tilo Wolf TW Hammer John A JA Gerdes Hans-Hermann HH

Cellular and molecular neurobiology 20090929 3

Axonal transport of peptide and hormone-containing large dense core vesicles (LDCVs) is known to be a microtubule-dependent process. Here, we suggest a role for the actin-based motor protein myosin Va specifically in retrograde axonal transport of LDCVs. Using live-cell imaging of transfected hippocampal neurons grown in culture, we measured the speed, transport direction, and the number of LDCVs that were labeled with ectopically expressed neuropeptide Y fused to EGFP. Upon expression of a domi ...[more]

PMID: 19787448

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Dataset Information

Dominant-negative myosin Va impairs retrograde but not anterograde axonal transport of large dense core vesicles.

Publications

Dominant-negative myosin Va impairs retrograde but not anterograde axonal transport of large dense core vesicles.

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