ABCMdb

PMID: 9804160

Vankeerberghen A, Wei L, Teng H, Jaspers M, Cassiman JJ, Nilius B, Cuppens H
Characterization of mutations located in exon 18 of the CFTR gene.
FEBS Lett. 1998 Oct 16;437(1-2):1-4., [PubMed]

Sentences

No. Mutations Sentence Comment

1 ABCC7 p.Asp1152His ABCC7 p.Asp1152His ABCC7 p.Ile1139Val ABCC7 p.Asp1154Gly ABCC7 p.Asp1154Gly ABCC7 p.Met1137Val ABCC7 p.Met1137Arg ABCC7 p.Met1137Arg ABCC7 p.Met1137Arg Of the different mutations present in transmembrane helix 12 (M1137V, M1137R, I1139V and vvM1140), and the intracytoplasmic loop connecting TM12 and NBD2 (D1152H and D1154G), only M1137R interfered with the proper maturation of the protein. Login to comment 3 ABCC7 p.Asp1152His ABCC7 p.Ile1139Val ABCC7 p.Asp1154Gly ABCC7 p.Met1137Val The whole cell cAMP activated chloride currents, however, were significantly reduced for M1137V, I1139V, D1152H and D1154G and close to zero for vvM1140, indicating that these mutations interfere with the proper gating of the chloride channels. Login to comment 15 ABCC7 p.Lys335Glu ABCC7 p.Lys95Asp The anion selectivity 'lter itself seems to be formed by the transmembrane helices [11], since mutagenesis of lysine 95 to aspartate and of lysine 335 to glutamate changed the anion selectivity of the channel. Login to comment 31 ABCC7 p.Asp1152His ABCC7 p.Asp1152His ABCC7 p.Ile1139Val ABCC7 p.Ile1139Val ABCC7 p.Asp1154Gly ABCC7 p.Asp1154Gly ABCC7 p.Met1137Val ABCC7 p.Met1137Val ABCC7 p.Met1137Arg ABCC7 p.Met1137Arg Six di¡erent mutations: a3541g ( = M1137V), t3542g ( = M1137R), a3547g ( = I1139V), deletion of atg from 3550 ( = vM1140), g3586c ( = D1152H) and a3593g ( = D1154G) were introduced using the Transformer Site-Directed Mutagenesis kit (Clontech). Login to comment 66 ABCC7 p.Met1137Arg Fig. 1 shows that the di&#a1;erent mutants, except M1137R, exhibit the same maturation pattern as wild-type CFTR. Login to comment 67 ABCC7 p.Met1137Arg ABCC7 p.Met1137Arg Fig. 1 shows that the di¡erent mutants, except M1137R, exhibit the same maturation pattern as wild-type CFTR. Login to comment 68 ABCC7 p.Met1137Arg ABCC7 p.Met1137Arg For M1137R, however, only the 150-kDa form was detected, even after 3 h and 30 min of chase time. Login to comment 69 ABCC7 p.Met1137Arg This indicates that the core glycosylated M1137R translation product is degraded in the ER before it can be transported to the cell surface. Login to comment 71 ABCC7 p.Met1137Val This hypothesis is substantiated by the 'nding that another mutation that a&#a1;ects the same amino acid residue, but that replaces it with an aliphatic one (M1137V), exhibits a `wild-type' maturation pattern. Login to comment 72 ABCC7 p.Met1137Val This hypothesis is substantiated by the 'nding that another mutation that a¡ects the same amino acid residue, but that replaces it with an aliphatic one (M1137V), exhibits a `wild-type' maturation pattern. Login to comment 77 ABCC7 p.Asp1152His ABCC7 p.Ile1139Val ABCC7 p.Asp1154Gly ABCC7 p.Met1137Val ABCC7 p.Met1137Arg COS1 cells transfected with wild-type, M1137V, M1137R, I1139V, vM1140, D1152H and D1154G CFTR were metabolically labelled, chased, CFTR was immunoprecipitated and separated on an SDS-PAGE gel. Login to comment 78 ABCC7 p.Asp1152His ABCC7 p.Ile1139Val ABCC7 p.Asp1154Gly ABCC7 p.Met1137Val ABCC7 p.Met1137Arg COS1 cells transfected with wild-type, M1137V, M1137R, I1139V, vM1140, D1152H and D1154G CFTR were metabolically labelled, chased, CFTR was immunoprecipitated and separated on an SDS-PAGE gel. Login to comment 79 ABCC7 p.Asp1152His ABCC7 p.Ile1139Val ABCC7 p.Asp1154Gly ABCC7 p.Met1137Val ABCC7 p.Met1137Arg M1137V, M1137R, I1139V and vM1140 are located in transmembrane helix 12 and D1152H and D1154G are located in the intracytoplasmic loop connecting TM12 and NBD2. Login to comment 80 ABCC7 p.Asp1152His ABCC7 p.Ile1139Val ABCC7 p.Asp1154Gly ABCC7 p.Met1137Val ABCC7 p.Met1137Arg M1137V, M1137R, I1139V and vM1140 are located in transmembrane helix 12 and D1152H and D1154G are located in the intracytoplasmic loop connecting TM12 and NBD. Login to comment 82 ABCC7 p.Asp1152His ABCC7 p.Ile1139Val ABCC7 p.Asp1154Gly ABCC7 p.Met1137Val ABCC7 p.Met1137Arg Four mutants, M1137V, I1139V, D1152H and D1154G showed a signi'cantly reduced current, when compared to wild type, and two other mutants, M1137R and vM1140 were not activated by cAMP (Fig. 3). Login to comment 83 ABCC7 p.Asp1152His ABCC7 p.Ile1139Val ABCC7 p.Asp1154Gly ABCC7 p.Met1137Val ABCC7 p.Met1137Arg ABCC7 p.Met1137Arg Four mutants, M1137V, I1139V, D1152H and D1154G showed a signi'cantly reduced current, when compared to wild type, and two other mutants, M1137R and vM1140 were not activated by cAMP (Fig. 3). Login to comment 84 ABCC7 p.Met1137Arg The absence of cAMP sensitive chloride currents found for M1137R is most probably caused by a defect in maturation, as found in COS1 cells. Login to comment 88 ABCC7 p.Asp1152His ABCC7 p.Ile1139Val ABCC7 p.Asp1154Gly ABCC7 p.Met1137Val The same permeation sequence was found for the four mutants, M1137V, I1139V, D1152H and D1154G (Fig. 2D). Login to comment 89 ABCC7 p.Asp1152His ABCC7 p.Asp1152His ABCC7 p.Ile1139Val ABCC7 p.Asp1154Gly ABCC7 p.Asp1154Gly ABCC7 p.Met1137Val The same permeation sequence was found for the four mutants, M1137V, I1139V, D1152H and D1154G (Fig. 2D). Login to comment 90 ABCC7 p.Asp1152His ABCC7 p.Asp1154Gly Mutations D1152H and D1154G are located in the intracytoplasmic loop that connects TM12 and NBD2 and thus only a¡ect the cAMP inducible whole cell currents. Login to comment 93 ABCC7 p.Met1137Arg One mutation (M1137R) did result in failure of protein maturation while the remainder did a&#a1;ect gating of the chloride channel. Login to comment 94 ABCC7 p.Met1137Arg One mutation (M1137R) did result in failure of protein maturation while the remainder did a¡ect gating of the chloride channel. Login to comment