ABCMdb

PMID: 17392477

Wendeler MW, Nufer O, Hauri HP
Improved maturation of CFTR by an ER export signal.
FASEB J. 2007 Aug;21(10):2352-8. Epub 2007 Mar 28., [PubMed]

Sentences

No. Mutations Sentence Comment

36 ABCC7 p.Leu1480Val Substitution of the most C-terminal leucine at position 1480 by valine was carried out by QuikChange mutagenesis (Stratagene, San Diego, CA, USA) using complementary oligonucleotides for changing codon CTT to GTT. Login to comment 86 ABCC7 p.Leu1480Val The wild-type tail and the modified tail with L1480V mutation (underlined) are shown. Login to comment 87 ABCC7 p.Leu1480Val B) HEK293 cells stably expressing wild-type or L1480V mutated CFTR constructs were pulse-labeled with [35 S]methionine for 20 min, chased for the indicated times, and subjected to immunoprecipitation with anti-CFTR antibodies. Login to comment 91 ABCC7 p.Leu1480Val Values of CFTR with C) wild-type tail (HEK clone 6) and D) L1480V modified tail (HEK293 clone 1). Login to comment 127 ABCC7 p.Leu1480Val A) HEK293 cells stably expressing wild-type or L1480V mutated CFTR constructs were pulse-labeled with [35 S]methionine, chased for the indicated times, and subjected to immunoprecipitation with anti-CFTR antibodies. Immunoprecipitates were then separated by SDS-PAGE and visualized by fluorography. Note that only the complex glycosylated mature form (band C) of CFTR constructs is detected. B) Quantification of fluorograms as shown in panel A. Login to comment 128 ABCC7 p.Leu1480Val Black data points indicate the complex glycosylated form of wild-type CFTR and white data points the complex glycosylated form of the CFTR L1480V mutation. Login to comment 131 ABCC7 p.Leu1480Val The L1480V substitution not only needs to be discussed in the context of ER export but also because L1480 is part of a PDZ binding motif. Login to comment 136 ABCC7 p.Leu1480Val The substitution of leucine 1480 by a valine reported here, however, is a conservative mutation not expected to interfere with PDZ binding, since it meets the PDZ type I consensus sequence S/T-X-V/ I/L/F/Y (43). Login to comment 137 ABCC7 p.Leu1480Val Accordingly, protein labeling of intact adherent cells by a membrane-impermeable biotinylation reagent showed that the L1480V substitution did not interfere with surface localization of mature CFTR (Fig. 2). Login to comment 163 ABCC7 p.Leu1480Val However, our results showed that the L1480V substitution on CFTR-⌬F508 was not able to overcome the retention of misfolded molecules. Login to comment