title: AMF-R tubules concentrate in a pericentriolar microtubule domain after MSV transformation of epithelial MDCK cells.
abstract: Autocrine motility factor receptor (AMF-R) is localized to an intracellular microtubule-associated membranous organelle, the AMF-R tubule. In well-spread untransformed MDCK epithelial cells, the microtubules originate from a broad perinuclear region and AMF-R tubules extend throughout the cytoplasm of the cells. In Moloney sarcoma virus (mos)-transformed MDCK (MSV-MDCK) cells, microtubules accumulate around the centrosome, forming a microtubule domain rich in stabilized detyrosinated microtubules. AMF-R tubules are quantitatively associated with this pericentriolar microtubule domain and the rough endoplasmic reticulum and lysosomes also co-distribute with the pericentriolar mass of microtubules. The Golgi apparatus is closely associated with the microtubule organizing center (MTOC) within the juxtanuclear mass of AMF-R tubules, and no co-localization of AMF-R tubules with the Golgi marker beta-COP could be detected by confocal microscopy. After nocodazole treatment and washout, microtubule nucleation occurs exclusively at the centrosome of MSV-MDCK cells, and only after microtubule extension to the cell periphery does the microtubule cytoskeleton reorganize to generate the pericentriolar microtubule domain after 30-60 min. AMF-R tubules dispersed by nocodazole treatment concentrate in the pericentriolar region in parallel with the reorganization of the microtubule cytoskeleton. MSV transformation of epithelial MDCK cells results in the stabilization of a pericentriolar microtubule domain responsible for the concentration and polarized distribution of AMF-R tubules.
authors.affiliation: Département d'Anatomie, Université de Montréal, Québec, Canada.
authors.forename: I R
authors.initials: IR
authors.lastname: Nabi
authors.forename: G
authors.initials: G
authors.lastname: Guay
authors.forename: D
authors.initials: D
authors.lastname: Simard
mesh_terms: D000818:Animals; D000941:Antigens / Q000032:analysis; D015703:Antigens, CD / Q000032:analysis; D002135:Calcium-Binding Proteins / Q000032:analysis; D037281:Calnexin; D002461:Cell Line, Transformed / Q000737:chemistry; D002467:Cell Nucleus / Q000648:ultrastructure; D002502:Centrioles / Q000648:ultrastructure; D020756:Coatomer Protein; D004285:Dogs; D004848:Epithelium / Q000737:chemistry / Q000648:ultrastructure; D019084:Fluorescent Antibody Technique, Indirect; D006056:Golgi Apparatus / Q000648:ultrastructure; D051907:Lysosomal Membrane Proteins; D008562:Membrane Glycoproteins / Q000032:analysis; D018613:Microscopy, Confocal; D008869:Microtubule-Associated Proteins / Q000032:analysis; D008870:Microtubules / Q000187:drug effects / Q000378:metabolism*; D008980:Moloney murine sarcoma virus; D015739:Nocodazole / Q000494:pharmacology; D060285:Receptors, Autocrine Motility Factor; D018121:Receptors, Cytokine / Q000032:analysis*; D014404:Tubulin / Q000032:analysis*; D044767:Ubiquitin-Protein Ligases
chemical_list: D000941:Antigens; D015703:Antigens, CD; D002135:Calcium-Binding Proteins; D020756:Coatomer Protein; D051907:Lysosomal Membrane Proteins; D008562:Membrane Glycoproteins; D008869:Microtubule-Associated Proteins; D018121:Receptors, Cytokine; D014404:Tubulin; C086178:pericentrin; D037281:Calnexin; D060285:Receptors, Autocrine Motility Factor; D044767:Ubiquitin-Protein Ligases; D015739:Nocodazole