ABCMdb

PMID: 11861646

Aleksandrov L, Aleksandrov AA, Chang XB, Riordan JR
The First Nucleotide Binding Domain of Cystic Fibrosis Transmembrane Conductance Regulator Is a Site of Stable Nucleotide Interaction, whereas the Second Is a Site of Rapid Turnover.
J Biol Chem. 2002 May 3;277(18):15419-25. Epub 2002 Feb 22., 2002-05-03 [PubMed]

Sentences

No. Mutations Sentence Comment

28 ABCC7 p.Lys1250Ala ABCC7 p.Lys464Ala ABCC7 p.Lys464Ala To distinguish between these possibilities, the Walker A lysine mutants K464A and K1250A were used; K464A ablated labeling of NBD1 without influencing that at NBD2, and hence the N3ADP that labeled * This work was supported by Grant DK51619 from the NIDDK, National Institutes of Health and by the Cystic Fibrosis Foundation. Login to comment 43 ABCC7 p.Lys1250Ala ABCC7 p.Lys464Ala Stable BHK-21 cell lines expressing wild-type and K464A and K1250A variants of CFTR were established and cultured as described previously (16, 17). Login to comment 130 ABCC7 p.Lys1250Ala ABCC7 p.Lys464Ala As expected, the mutations K464A and K1250A prevented photolabeling with either 8-azido-ATP or 8-azido-ADP of NBD1 and NBD2, respectively. Login to comment 131 ABCC7 p.Lys1250Ala ABCC7 p.Lys464Ala However, there was no indication that the mutation in one domain had any influence on the labeling of the other, i.e. in K464A, NBD2 was labeled as in wild-type and in K1250A, NBD1 was not different from wild type. Login to comment 141 ABCC7 p.Lys464Ala Hence, as with a mutation (K464A) that prevents labeling of NBD1 by N3ATP, occupation of the domain by AMP-PNP leaves the labeling of NBD2 with [␣-32 P]N3ATP entirely intact. Login to comment 191 ABCC7 p.Lys1250Ala ABCC7 p.Lys464Ala Membranes from BHK cells expressing wild-type and K464A and K1250A variants of CFTR were incubated as in Figs. Login to comment 193 ABCC7 p.Lys464Ala The mobility of the large 95-kDa, NBD2 band is increased in the K464A variant, which does not mature and completely acquire the complex oligosaccharide chains, which contribute to the apparent size of the wild-type band. Login to comment