title: Microtubule-dependent transport of secretory vesicles in RBL-2H3 cells.
abstract: Antigen-mediated activation of mast cells results in Ca2+-dependent exocytosis of preformed mediators of the inflammatory response. To investigate the role of secretory vesicle motility in this response, we have performed time-lapse confocal microscopy on RBL-2H3 cells transfected with a green fluorescent protein-Fas ligand fusion protein (GFP-FasL). Green fluorescent protein-labeled vesicles exhibit rapid, bidirectional movement in both resting and activated cells and can be localized adjacent to microtubules. Colchicine treatment inhibits the motility of secretory vesicles as measured by fluorescence recovery after photobleaching (FRAP). Colchicine also inhibits both the extent and the rate of exocytosis triggered by receptor activation or by Ca2+ ionophore, demonstrating that microtubule-dependent movement of secretory vesicles plays an important role in the exocytic response.
authors.affiliation: Department of Pathology and Cancer Research & Treatment Center, University of New Mexico Health Sciences Center, New Mexico, USA.
authors.forename: Alexander J
authors.initials: AJ
authors.lastname: Smith
authors.forename: Janet R
authors.initials: JR
authors.lastname: Pfeiffer
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.forename: A Marina
authors.initials: AM
authors.lastname: Martinez
authors.forename: Gillian M
authors.initials: GM
authors.lastname: Griffiths
authors.forename: Bridget S
authors.initials: BS
authors.lastname: Wilson
mesh_terms: D000818:Animals; D003078:Colchicine / Q000494:pharmacology; D005089:Exocytosis / Q000187:drug effects; D053222:Fas Ligand Protein; D005455:Fluorescent Antibody Technique; D017930:Genes, Reporter; D006801:Humans; D008407:Mast Cells / Q000187:drug effects / Q000378:metabolism*; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism; D008870:Microtubules / Q000187:drug effects / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D022142:Secretory Vesicles / Q000187:drug effects / Q000378:metabolism*; D012701:Serotonin / Q000378:metabolism
chemical_list: C505661:FASLG protein, human; D053222:Fas Ligand Protein; D008562:Membrane Glycoproteins; D011993:Recombinant Fusion Proteins; D012701:Serotonin; D003078:Colchicine