title: Movement of plasma-membrane-associated clathrin spots along the microtubule cytoskeleton.
abstract: The current understanding of the role of plasma- membrane-associated clathrin suggests that clathrin-coated pits form at the sites of activated receptors and then, following internalization, the clathrin coat is rapidly shed. Utilizing total internal reflection fluorescence microscopy (TIR-FM), we have documented linear lateral motion of cell-surface-associated dsRed-clathrin spots parallel to the plasma membrane. Clathrin spot motility was observed in multiple cell lines (MDCK, CHO, Cos-7 and HeLa). In MDCK cells dsRed-clathrin spots moved along linear pathways up to 4 micro m in length with rates of approximately 0.8 micro m/s. Spots did not generally undergo internalization during movement. The motion of these puncta was coincident with the microtubule cytoskeleton, and depolymerization of microtubules reduced spot motility over 10-fold. Over-expression of the microtubule-associated protein tau-EGFP decreased spot run length by 40% without affecting the rate of movement. Thus dsRed-clathrin puncta move along the microtubule cytoskeleton parallel to the cell surface.
authors.affiliation: The Laboratory of Cellular Biophysics, The Rockefeller University, 1230 York Avenue, Box 304, New York, New York, 10021, USA.
authors.forename: Joshua Z
authors.initials: JZ
authors.lastname: Rappoport
authors.forename: Bushra W
authors.initials: BW
authors.lastname: Taha
authors.forename: Sanford M
authors.initials: SM
authors.lastname: Simon
mesh_terms: D000818:Animals; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism*; D002966:Clathrin / Q000378:metabolism*; D015638:Cytochalasin D / Q000378:metabolism; D003599:Cytoskeleton / Q000378:metabolism*; D049452:Green Fluorescent Proteins; D006801:Humans; D008164:Luminescent Proteins / Q000378:metabolism; D008856:Microscopy, Fluorescence / Q000379:methods; D008870:Microtubules / Q000378:metabolism*; D015739:Nocodazole / Q000378:metabolism; D021381:Protein Transport; D014404:Tubulin / Q000378:metabolism
chemical_list: D002966:Clathrin; D008164:Luminescent Proteins; D014404:Tubulin; C413663:fluorescent protein 583; D049452:Green Fluorescent Proteins; D015638:Cytochalasin D; D015739:Nocodazole