Dynasore inhibits removal of wild-type and DeltaF508 cystic fibrosis transmembrane conductance regulator (CFTR) from the plasma membrane.
Dynasore, a small molecule inhibitor of dynamin, was used to probe the role of dynamin in the endocytosis of wild-type and mutant CFTR (cystic fibrosis transmembrane conductance regulator). Internalization of both wild-type and 'temperature-corrected' DeltaF508 CFTR was markedly inhibited by a short exposure to dynasore, implicating dynamin as a key element in the endocytic internalization of both wild-type and mutant CFTR. The inhibitory effect of dynasore was readily reversible upon washout of dynasore from the growth media. Corr-4 ({2-(5-chloro-2-methoxy-phenylamino)-4'-methyl-[4,5']-bithiazolyl-2'-yl}-phenyl-methanonone), a pharmacological corrector of DeltaF508 CFTR biosynthesis, caused a marked increase in the cell surface expression of mutant CFTR. Co-incubation of DeltaF508 CFTR expressing cells with Corr-4 and dynasore caused a significantly greater level of cell surface CFTR than that observed in the presence of Corr-4 alone. These results argue that inhibiting the endocytic internalization of mutant CFTR provides a novel therapeutic target for augmenting the benefits of small molecule correctors of mutant CFTR biosynthesis.
Young
Andrew
A
Department of Physiology and Biophysics, Chicago Medical School, 3333 Green Bay Road, North Chicago, IL 60064, USA.
Gentzsch
Martina
M
Abban
Cynthia Y
CY
Jia
Ying
Y
Meneses
Patricio I
PI
Bridges
Robert J
RJ
Bradbury
Neil A
NA
D002462:Cell Membrane / Q000187:drug effects* / Q000378:metabolism*; D003550:Cystic Fibrosis / Q000235:genetics / Q000378:metabolism*; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics / Q000378:metabolism*; D015536:Down-Regulation; D004705:Endocytosis / Q000187:drug effects; D006367:HeLa Cells; D006801:Humans; D006835:Hydrazones / Q000494:pharmacology*; D021381:Protein Transport / Q000187:drug effects
D006835:Hydrazones; C511794:N'-(3,4-dihydroxybenzylidene)-3-hydroxy-2-naphthahydrazide; D019005:Cystic Fibrosis Transmembrane Conductance Regulator