ABCMdb

PMID: 19910674

Ramalho AS, Lewandowska MA, Farinha CM, Mendes F, Goncalves J, Barreto C, Harris A, Amaral MD
Deletion of CFTR translation start site reveals functional isoforms of the protein in CF patients.
Cell Physiol Biochem. 2009;24(5-6):335-46. Epub 2009 Nov 4., [PubMed]

Sentences

No. Mutations Sentence Comment

126 ABCC7 p.Met152Val ABCC7 p.Met152Val ABCC7 p.Met82Val ABCC7 p.Met156Val ABCC7 p.Met156Val ABCC7 p.Met156Val ABCC7 p.Met150Val ABCC7 p.Met150Val ABCC7 p.Met150Val jointly mutated into valines and the respective stable cells wereanalysedbyimmunoblotforCFTR.ResultsinFig.5A reveal the presence of two proteins (D and E) for single mutants of M82V, M150V, M152V and M156V (lanes 36, respectively) and also for the double mutants M150V/ M152, M150V/M156V and M152V/M156V (lanes 7-9). Login to comment 130 ABCC7 p.Met152Val ABCC7 p.Met82Val ABCC7 p.Met150Val Individual and double mutations of M82V, M150V and M152V (lanes 5-8) did not cause loss of either protein species D or E, consistent with the corresponding constructs in the in vivo assay. Login to comment 131 ABCC7 p.Met152Val ABCC7 p.Met82Val ABCC7 p.Met150Val The mutant M82V/M150V/M152V (lane 4) does not alter the production of proteins D and E either. Login to comment 133 ABCC7 p.Met82Val Thus, this species likely corresponds to the CFTR variant resulting from usage of M150/M152 or M156 (and not of M82 because the M82V mutation alone did not abolish the appearance of this band). Login to comment 140 ABCC7 p.Met152Val ABCC7 p.Met152Val ABCC7 p.Met152Val ABCC7 p.Met152Val ABCC7 p.Met82Val ABCC7 p.Met156Val ABCC7 p.Met156Val ABCC7 p.Met156Val ABCC7 p.Met156Val ABCC7 p.Met150Val ABCC7 p.Met150Val ABCC7 p.Met150Val ABCC7 p.Met150Val Lanes 3-10 correspond to the proteins produced by the methionines mutants all in the c.120del23-CFTR pNUT background: lane 3, M82V; lane 4, M150V; lane 5 M152V; lane 6, M156V; lane 7, M150V/M152V; lane 8, M150V/M156V; lane 9, M152V/M156V; lane 10, M150V/M152V/M156V. Login to comment 144 ABCC7 p.Met152Val ABCC7 p.Met152Val ABCC7 p.Met152Val ABCC7 p.Met82Val ABCC7 p.Met82Val ABCC7 p.Met82Val ABCC7 p.Met82Val ABCC7 p.Met156Val ABCC7 p.Met150Val ABCC7 p.Met150Val ABCC7 p.Met150Val Lanes 2-8 all in pSP73: 2, CFTR exons 2-24; 3, M82V/ M150V/M152V/M156V; 4, M82V/M150V/M152V; 5, M82/M152V; 6, M82V/M150V;7, M150; 8, M82V. Login to comment 148 ABCC7 p.Met152Val ABCC7 p.Met156Val ABCC7 p.Met150Val However, when the triple mutant (M150V/M152V/M156V) was analysed (lane 10, Fig.5A), only the lower form (E ~128 kDa) could be detected. Login to comment 172 ABCC7 p.Gly85Glu ABCC7 p.Ser50Pro ABCC7 p.Glu92Lys ABCC7 p.Glu60Lys Altogether, these results for c.120del23-CFTR suggest an important role of the N-terminus in CFTR folding, stability and processing, which was also evidenced by other studies demonstrating that point mutations in this region - S50P; E60K; G85E/V; E92K - prevent CFTR maturation [35, 36]. Login to comment 189 ABCC7 p.Arg560Thr Functional studies of 120del23-CFTR Despite its intrinsic instability and the very low membrane levels of this mutant, we find here that c.120del23-CFTR, still has residual Cl-channel activity, in contrast to other CF-causing mutants like F508del-CFTR (this study) and R560T-, orA561E-CFTR [14, 15]. Login to comment