ABCMdb

PMID: 9511932

Clancy JP, Bebok Z, Sorscher EJ
Purification, characterization, and expression of CFTR nucleotide-binding domains.
J Bioenerg Biomembr. 1997 Oct;29(5):475-82., [PubMed]

Sentences

No. Mutations Sentence Comment

60 ABCC7 p.Gly551Asp (6,17) NUCLEOTIDE BINDING BY CFTR NBD-1 In Vitro The second most common CFTR mutation is the replacement of a glycine by aspartic acid at CFTR position 551 (G551D). Login to comment 62 ABCC7 p.Gly551Asp We studied the nucleotide binding characteristics of the wild type CFTR NBD-1, and also NBD-1 containing AF508 or G551D. Login to comment 63 ABCC7 p.Gly551Asp As shown in Fig. 2, while the AF508 mutation had no effect on binding of the nucleotide analog trinitrophenol ATP, the G551D mutation significantly decreased nucleotide binding by this recombinant CFTR domain. Login to comment 64 ABCC7 p.Gly1349Asp To confirm that glycine within this motif was important in nucleotide interactions, the corresponding glycine-aspartic acid replacement was made in CFTR NBD-2 (G1349D), and nucleotide binding was compared with thepurified wild type region. Login to comment 65 ABCC7 p.Gly1349Asp The clinically important NBD-2 mutation G1349D led to decreased nucleotide binding by NBD-2. Login to comment 72 ABCC7 p.Gly551Asp CFTR NBD-1, as well as NBD-1containing the AF508 and the G551D mutations,were dissolvedin 10 mM Tris, pH 7.4. Login to comment 75 ABCC7 p.Gly1349Asp NBD-2 polypeptides with and without the G1349D mutation were compared by trinitrophenol ATP binding. Login to comment 76 ABCC7 p.Gly1349Asp The glycine-to-aspartic acid mutation at position 1349 substantially decreased the affinity of the second nucleotide binding domain for TNP-ATP. Login to comment 79 ABCC7 p.Gly551Asp ABCC7 p.Gly551Asp ABCC7 p.Gly551Asp (18) An alternative explanation, that in vitro folding of the domain is grossly disrupted by the G551D mutation, was also considered, However, the CD spectrum of the folded G551D NBD-1 did not differ from either AF508 or wild type NBD-1, and the G551D CFTR protein is not recognized as misfolded, at least insofar as the cellular quality control pathways responsible for CFTR processing are concerned. Login to comment 80 ABCC7 p.Gly551Asp Nevertheless, high-resolution structural studies will be necessary in order to determine whether decreased binding by G551D NBD-1 is due to a replacement of a neutral residuewith an exposed negatively charged aspartic acid, possibly blocking entry of negatively charged ATP molecules into a nucleotide binding pocket within the NBD-1. Login to comment 116 ABCC7 p.Gly551Asp This finding supports other observations that G551D is normally processed to the plasma membrane, but maintains little or no residual function. Login to comment