Real-time visualization of processive myosin 5a-mediated vesicle movement in living astrocytes
AuthorsStachelek, Stanley J.
Tuft, Richard A.
Lifschitz, Lawrence M.
Farwell, Alan P.
Leonard, Jack L.
UMass Chan AffiliationsProgram in Molecular Medicine
Department of Physiology
Department of Cellular and Molecular Physiology
Graduate School of Biomedical Sciences
Document TypeJournal Article
KeywordsActins; Animals; Animals, Newborn; Astrocytes; Base Sequence; Cell Movement; DNA Primers; Myosins; Rats
Medicine and Health Sciences
MetadataShow full item record
AbstractRecycling endosomes in astrocytes show hormone-regulated, actin fiber-dependent delivery to the endosomal sorting pool. Recycling vesicle trafficking was followed in real time using a fusion protein composed of green fluorescent protein coupled to the 29-kDa subunit of the short-lived, membrane-bound enzyme type 2 deiodinase. Primary endosomes budded from the plasma membrane and oscillated near the cell periphery for 1-4 min. The addition of thyroid hormone triggered the processive, centripetal movement of the recycling vesicle in linear bursts at velocities of up to 200 nm/s. Vesicle migration was hormone-specific and blocked by inhibitors of actin polymerization and myosin ATPase. Domain mapping confirmed that the hormone-dependent vesicle-binding domain was located at the C terminus of the motor. In addition, the interruption of normal dimerization of native myosin 5a monomers inactivated vesicle transport, indicating that single-headed myosin 5a motors do not transport cargo in situ. This is the first demonstration of processive hormone-dependent myosin 5a movement in living cells.
SourceJ Biol Chem. 2001 Sep 21;276(38):35652-9. Epub 2001 Aug 9. Link to article on publisher's site
Permanent Link to this Itemhttp://hdl.handle.net/20.500.14038/32596
Related ResourcesLink to Article in PubMed