title: Matrine modulates HSC70 levels and rescues ΔF508-CFTR.
abstract: Cystic fibrosis transmembrane conductance regulator (CFTR) is a cAMP-dependent Cl(-) channel located in the plasma membrane, and its malfunction results in cystic fibrosis (CF), the most common lethal genetic disease in Caucasians. Most CF patients carry the deletion of Phe508 (ΔF508 mutation); this mutation prevents the delivery of the CFTR to its correct cellular location, the apical (lumen-facing) membrane of epithelial cells. Molecular chaperones play a central role in determining the fate of ΔF508-CFTR. In this report, we show that the Matrine, a quinolizidine alkaloid, downregulates the expression of the molecular chaperone HSC70 and increases the protein levels of ΔF508-CFTR in human alveolar basal epithelial cells (A549 cell line), stably transfected with a ΔF508-CFTR-expressing construct. Moreover, Matrine induced ΔF508-CFTR release from endoplasmic reticulum to cell cytosol and its localization on the cell membrane. Interestingly, downregulation of HSC70 resulted in increased levels of ΔF508-CFTR complexes with the co-chaperone BAG3 that in addition appeared to co-localize with the mutated protein on the cell surface. These results shed new light on ΔF508-CFTR interactions with proteins of the chaperones/co-chaperones system and could be useful in strategies for future medical treatments for CF.
authors.affiliation: Department of Pharmaceutical Sciences (FARMABIOMED), University of Salerno, Fisciano (SA), Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Basile
authors.forename: Maria
authors.initials: M
authors.lastname: Pascale
authors.forename: Silvia
authors.initials: S
authors.lastname: Franceschelli
authors.forename: Erika
authors.initials: E
authors.lastname: Nieddu
authors.forename: Marco T
authors.initials: MT
authors.lastname: Mazzei
authors.forename: Paola
authors.initials: P
authors.lastname: Fossa
authors.forename: Maria Caterina
authors.initials: MC
authors.lastname: Turco
authors.forename: Mauro
authors.initials: M
authors.lastname: Mazzei
mesh_terms: D000470:Alkaloids / Q000494:pharmacology*; D002460:Cell Line; D002462:Cell Membrane / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D003550:Cystic Fibrosis / Q000235:genetics / Q000378:metabolism; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics / Q000378:metabolism*; D004721:Endoplasmic Reticulum / Q000187:drug effects; D004847:Epithelial Cells / Q000187:drug effects; D005786:Gene Expression Regulation / Q000187:drug effects*; D050883:HSC70 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D018832:Molecular Chaperones / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D011485:Protein Binding; D011807:Quinolizines / Q000494:pharmacology*; D000093842:Matrines
chemical_list: D000470:Alkaloids; C505032:CFTR protein, human; D050883:HSC70 Heat-Shock Proteins; C494371:HSPA8 protein, human; D018832:Molecular Chaperones; D011807:Quinolizines; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; D000093842:Matrines