ABCMdb

PMID: 23788656

Namkung W, Park J, Seo Y, Verkman AS
Novel amino-carbonitrile-pyrazole identified in a small molecule screen activates wild-type and DeltaF508 cystic fibrosis transmembrane conductance regulator in the absence of a cAMP agonist.
Mol Pharmacol. 2013 Sep;84(3):384-92. doi: 10.1124/mol.113.086348. Epub 2013 Jun 20., [PubMed]

Sentences

No. Mutations Sentence Comment

9 ABCC7 p.Gly551Asp ABCC7 p.Gly551Asp ABCC7 p.Tyr1092* In FRT cells expressing G551D-CFTR and in CF nasal polyp epithelial cells (from a heterozygous G551D/ Y1092X-CFTR patient), Cact-A1 produced little Cl2 current by itself but showed synergy with forskolin. Login to comment 13 ABCC7 p.Gly551Asp Several new approaches for drug therapy of CF have emerged, including Ivacaftor [VX-770; N-(2,4-di-tert-butyl-5- hydroxyphenyl)-4-oxo-1,4-dihydroquinoline-3-carboxamide], a CFTR potentiator approved to treat CF patients with the G551D-CFTR mutation (Davis, 2011). Login to comment 14 ABCC7 p.Gly551Asp Clinical trials of Ivacaftor in CF patients with the G551D mutation on at least one CFTR allele showed improvements in lung function, pulmonary exacerbations, patient-reported respiratory symptoms, body weight, and sweat chloride concentration (Ramsey et al., 2011; Davis et al., 2012). Login to comment 41 ABCC7 p.Gly551Asp Fisher rat thyroid (FRT) cells expressing human WT-, DF508-, and G551D-CFTR, and TMEM16A (abc) were grown in F-12 Modified Coon`s medium supplemented with 10% fetal bovine serum, 2 mM glutamine, 100 units/ml penicillin, and 100 mg/ml streptomycin. Login to comment 161 ABCC7 p.Gly551Asp Cact-A1 Also Activates and Potentiates G551D-CFTR. Login to comment 162 ABCC7 p.Gly551Asp ABCC7 p.Gly551Asp Cact-A1 activation of the CF-causing gating mutant G551D-CFTR was investigated in G551D-CFTR expressing FRT cells. Login to comment 163 ABCC7 p.Gly551Asp Cact-A1 (30 mM) and forskolin (20 mM), each alone, produced weak activation of G551D-CFTR (Fig. 6, A and B). Login to comment 164 ABCC7 p.Gly551Asp However, combined application of Cact-A1 and forskolin showed synergistic activation of G551D-CFTR, albeit much smaller than the potentiation effect of VX-770. Login to comment 165 ABCC7 p.Gly551Asp VX-770 (10 mM) strongly increased both forskolinand Cact-A1-stimulated G551D-CFTR Cl2 current. Login to comment 166 ABCC7 p.Gly551Asp Interestingly, Cact-A1 potentiated the G551D-CFTR Cl2 current activated by maximal forskolin with VX-770 (Fig. 6A, top left). Login to comment 167 ABCC7 p.Gly551Asp Figure 6C shows whole-cell patch-clamp recordings in G551D-CFTR expressing FRT cells. Login to comment 183 ABCC7 p.Gly551Asp Cact-A1 significantly increased G551D-CFTR current produced by maximal forskolin and VX-770, in agreement with the short-circuit current data. Login to comment 184 ABCC7 p.Gly551Asp ABCC7 p.Tyr1092* We also measured short-circuit current in primary cultures of human nasal polyp epithelial cells generated from a compound heterozygous CF patient with G551D/Y1092X-CFTR mutations. Login to comment 185 ABCC7 p.Tyr1092* The Y1092X mutation is a nonsense mutation that does not produce functional protein (Bozon et al., 1994). Login to comment 198 ABCC7 p.Gly551Asp ABCC7 p.Gly551Asp G551D-CFTR is weakly activated but strongly potentiated by Cact-A1 in G551D-CFTR expressing FRT cells. Login to comment 199 ABCC7 p.Gly551Asp (A) G551D-CFTR was stimulated by application of 30 mM Cact-A1, 20 mM forskolin, and 10 mM VX-770. Login to comment 200 ABCC7 p.Gly551Asp G551D-CFTR-dependent current was inhibited by 20 mM CFTRinh-172. Login to comment 202 ABCC7 p.Gly551Asp ABCC7 p.Gly551Asp (C) Whole-cell G551D-CFTR currents were recorded at a holding potential at 0 mV, and pulsing to voltages between 680 mV (in steps of 20 mV) in G551D-CFTR-expressing FRT cells. Login to comment