title: Analysis of conventional and unconventional trafficking of CFTR and other membrane proteins.
abstract: The cystic fibrosis transmembrane conductance regulator (CFTR) is a polytopic transmembrane protein that functions as a cAMP-activated anion channel at the apical membrane of epithelial cells. Mutations in CFTR cause cystic fibrosis and are also associated with monosymptomatic diseases in the lung, pancreas, intestines, and vas deferens. Many disease-causing CFTR mutations, including the deletion of a single phenylalanine residue at position 508 (ΔF508-CFTR), result in protein misfolding and trafficking defects. Therefore, intracellular trafficking of wild-type and mutant CFTR has been studied extensively, and results from these studies significantly contribute to our general understanding of mechanisms involved in the cell-surface trafficking of membrane proteins. CFTR is a glycoprotein that undergoes complex N-glycosylation as it passes through Golgi-mediated conventional exocytosis. Interestingly, results from recent studies revealed that CFTR and other membrane proteins can reach the plasma membrane via an unconventional alternative route that bypasses Golgi in specific cellular conditions. Here, we describe methods that have been used to investigate the conventional and unconventional surface trafficking of CFTR. With appropriate modifications, the protocols described in this chapter can also be applied to studies investigating the intracellular trafficking of other plasma membrane proteins.
authors.affiliation: Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Severance Biomedical Science Institute, Yonsei University College of Medicine, 134 Sinchon-Dong, Seoul, 120-752, Korea.
authors.forename: Heon Yung
authors.initials: HY
authors.lastname: Gee
authors.forename: Joo Young
authors.initials: JY
authors.lastname: Kim
authors.forename: Min Goo
authors.initials: MG
authors.lastname: Lee
mesh_terms: D002460:Cell Line; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000378:metabolism*; D004705:Endocytosis; D005455:Fluorescent Antibody Technique; D006801:Humans; D007150:Immunohistochemistry; D008565:Membrane Proteins / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D021381:Protein Transport; D055571:Secretory Pathway
chemical_list: D008565:Membrane Proteins; D019005:Cystic Fibrosis Transmembrane Conductance Regulator