ABCMdb

PMID: 9822656

Cotten JF, Welsh MJ
Covalent modification of the nucleotide binding domains of cystic fibrosis transmembrane conductance regulator.
J Biol Chem. 1998 Nov 27;273(48):31873-9., 1998-11-27 [PubMed]

Sentences

No. Mutations Sentence Comment

37 ABCC7 p.Cys832Ala ABCC7 p.Cys832Ala ABCC7 p.Ser1248Cys ABCC7 p.Ala462Cys 1 The abbreviations used are: CFTR, cystic fibrosis transmembrane conductance regulator; NEM, N-ethylmaleimide; PKA, catalytic subunit of cAMP-dependent protein kinase; ABC, ATP-binding cassette; NBD, nucleotide binding domain; NBD1-Cys, A462C/C832A; NBD2-Cys, C832A/S1248C; TB, mean burst duration; g, single channel conductance; ␶cs, slow, long closed time interval; ␶o, open time interval; ␶, time constant for rate of NEM modification; Iϱ, percentage of current remaining following complete NEM modification; TES, N-tris[hydroxymethyl]methyl-2-aminoethanesulfonic acid. Login to comment 73 ABCC7 p.Cys832Ala ABCC7 p.Cys832Ala ABCC7 p.Cys832Ala ABCC7 p.Ser1248Cys ABCC7 p.Ala462Cys NEM inhibits NBD1-Cys (CFTR-A462C/C832A) and NBD2-Cys(CFTR-S1248C/C832A) channel activity in an ATP-dependent manner. A, CFTR-C832A; B, CFTR-NBD1-Cys; C, CFTR-NBD2-Cys. Login to comment 85 ABCC7 p.Cys832Ala Both NBD1-Cys and NBD2-Cys mutants also contain the C832A mutation. Login to comment 87 ABCC7 p.Cys832Ala To determine the functional consequences of NEM modification of the NBDs, we applied 100 ␮M NEM to the cytoplasmic side of excised membrane macropatches containing CFTR-C832A (control), NBD1-Cys, or NBD2-Cys mutant channels. Login to comment 88 ABCC7 p.Cys832Ala As we have shown previously (33), 100 ␮M NEM had a slight stimulatory effect on CFTR-C832A channel activity (Fig. 2A). Login to comment 102 ABCC7 p.Cys832Ala The NEM response of the CFTR-C832A mutant is also quantified in Fig. 3B. Login to comment 118 ABCC7 p.Cys832Ala Our earlier work showed that NEM did not alter the single channel properties of CFTR-C832A (33). Login to comment 129 ABCC7 p.Cys832Ala B, percentage of current remaining 5 min after application of 100 ␮M NEM for CFTR-C832A (control) and NBD1-Cys mutants. Login to comment 253 ABCC7 p.Gly551Asp For example, Li et al. showed that the G551D mutation in NBD1 eliminates most of CFTR ATPase activity (15). Login to comment