Correctors Rescue CFTR Mutations in Nucleotide‐Binding Domain 1 (NBD1) by Modulating Proteostasis. (16th February 2016)

• Record Type: Journal Article
• Authors: Lopes‐Pacheco, Miquéias; Sabirzhanova, Inna; Rapino, Daniele; Morales, Marcelo M.; Guggino, William B.; Cebotaru, Liudmila
• Is Part Of: Chembiochem. Volume 17:Number 6(2016)
• Page Start: 493
• Page End: 505
• Publication Date: 2016-02-16
• Subjects: correctors -- cystic fibrosis -- mutagenesis -- protein misfolding -- proteostasis network; Biochemistry -- Periodicals; Molecular biology -- Periodicals; Pharmaceutical chemistry -- Periodicals; 572
• DOI: 10.1002/cbic.201500620
• Languages: English
• ISSNs: 1439-4227

Abstract

Abstract: We evaluated whether small molecule correctors could rescue four nucleotide‐binding domain 1 (NBD1) mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene (A455E, S492F, ΔI507, and R560T). We first transfected Cos‐7 cells (green monkey kidney cells) with A455E, S492F, ΔI507, or R560T and created HEK‐293 (human embryonic kidney cells) cell lines stably expressing these CFTR mutations. The mutants showed lowered protein expression, instability at physiological temperature, and rapid degradation. After treatment with correctors CFFT‐002, CFFT‐003, C3, C4, and/or C18, the combination of C18+C4 showed the most correction and resulted in increased CFTR residing in the plasma membrane. We found a profound decrease in binding of CFTR to histone deacetylases (HDAC) 6 and 7 and heat shock proteins (Hsps) 27 and 40. Silencing Hsp27 or 40 rescued the mutants, but no additional amount of CFTR was rescued when both proteins were knocked down simultaneously. Thus, CFTR mutations in NBD1 can be rescued by a combination of correctors, and the treatment alters the interaction between mutated CFTR and the endoplasmic reticulum machinery. Abstract : Correctors to the rescue ! Cystic fibrosis mutations in nucleotide binding domain 1 often affect the function and processing of CFTR. This study shows that a combination of chemical correctors rescue mutant CFTR by causing a profound decrease in the binding of CFTR to proteins involved in the endoplasmic reticulum quality control machinery.