11 research outputs found
Transcytosis of Polymeric Immunoglobulin A in Polarized Madin–Darby Canine Kidney Cells
Selective Perturbation of Apical Membrane Traffic by Expression of Influenza M2, an Acid-activated Ion Channel, in Polarized Madin–Darby Canine Kidney Cells
Sorting of Membrane and Fluid at the Apical Pole of Polarized Madin-Darby Canine Kidney Cells
Analyse épidémiologique, histologique et immunohistochimique du rhabdomyosarcome de la tête et du cou chez l’enfant
Modulation of Endocytic Traffic in Polarized Madin-Darby Canine Kidney Cells by the Small GTPase RhoA
Selective Alterations in Biosynthetic and Endocytic Protein Traffic in Madin-Darby Canine Kidney Epithelial Cells Expressing Mutants of the Small GTPase Rac1
Transduction of Basolateral-to-Apical Signals across Epithelial Cells: Ligand-stimulated Transcytosis of the Polymeric Immunoglobulin Receptor Requires Two Signals
Actin Filaments and Microtubules are Involved in Different Membrane Traffic Pathways That Transport Sphingolipids to the Apical Surface of Polarized HepG2 Cells
In polarized HepG2 hepatoma cells, sphingolipids are transported to the apical, bile canalicular membrane by two different transport routes, as revealed with fluorescently tagged sphingolipid analogs. One route involves direct, transcytosis-independent transport of Golgi-derived glucosylceramide and sphingomyelin, whereas the other involves basolateral to apical transcytosis of both sphingolipids. We show that these distinct routes display a different sensitivity toward nocodazole and cytochalasin D, implying a specific transport dependence on either microtubules or actin filaments, respectively. Thus, nocodazole strongly inhibited the direct route, whereas sphingolipid transport by transcytosis was hardly affected. Moreover, nocodazole blocked “hyperpolarization,” i.e., the enlargement of the apical membrane surface, which is induced by treating cells with dibutyryl-cAMP. By contrast, the transcytotic route but not the direct route was inhibited by cytochalasin D. The actin-dependent step during transcytotic lipid transport probably occurs at an early endocytic event at the basolateral plasma membrane, because total lipid uptake and fluid phase endocytosis of horseradish peroxidase from this membrane were inhibited by cytochalasin D as well. In summary, the results show that the two sphingolipid transport pathways to the apical membrane must have a different requirement for cytoskeletal elements