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.
Department of Physiology and Biophysics, Chicago Medical School, 3333 Green Bay Road, North Chicago, IL 60064, USA.
Andrew
A
Young
Martina
M
Gentzsch
Cynthia Y
CY
Abban
Ying
Y
Jia
Patricio I
PI
Meneses
Robert J
RJ
Bridges
Neil A
NA
Bradbury
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