ABCMdb

ABCC7 p.Leu167Arg

ClinVar:	c.500T>G , p.Leu167Arg ? , not provided
Predicted by SNAP2:	A: N (53%), C: D (59%), D: D (91%), E: D (85%), F: D (66%), G: D (91%), H: D (85%), I: D (53%), K: D (85%), M: N (93%), N: D (85%), P: D (91%), Q: D (80%), R: D (85%), S: D (80%), T: D (80%), V: D (53%), W: D (80%), Y: D (80%),
Predicted by PROVEAN:	A: D, C: D, D: D, E: D, F: D, G: D, H: D, I: N, K: D, M: N, N: D, P: D, Q: D, R: D, S: D, T: D, V: N, W: D, Y: D,

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Publications
[hide] Orphan missense mutations in the cystic fibrosis t... J Mol Diagn. 2011 Sep;13(5):520-7. Epub 2011 Jun 25. Fresquet F, Clement R, Norez C, Sterlin A, Melin P, Becq F, Kitzis A, Thoreau V, Bilan F
Orphan missense mutations in the cystic fibrosis transmembrane conductance regulator a three-step biological approach to establishing a correlation between genotype and phenotype.
J Mol Diagn. 2011 Sep;13(5):520-7. Epub 2011 Jun 25., [PMID:21708286]

Abstract [show]
More than 1860 mutations have been found within the human cystic fibrosis transmembrane conductance regulator (CFTR) gene sequence. These mutations can be classified according to their degree of severity in CF disease. Although the most common mutations are well characterized, few data are available for rare mutations. Thus, genetic counseling is particularly difficult when fetuses or patients with CF present these orphan variations. We describe a three-step in vitro assay that can evaluate rare missense CFTR mutation consequences to establish a correlation between genotype and phenotype. By using a green fluorescent protein-tagged CFTR construct, we expressed mutated proteins in COS-7 cells. CFTR trafficking was visualized by confocal microscopy, and the cellular localization of CFTR was determined using intracellular markers. We studied the CFTR maturation process using Western blot analysis and evaluated CFTR channel activity by automated iodide efflux assays. Of six rare mutations that we studied, five have been isolated in our laboratory. The cellular and functional impact that we observed in each case was compared with the clinical data concerning the patients in whom we encountered these mutations. In conclusion, we propose that performing this type of analysis for orphan CFTR missense mutations can improve CF genetic counseling.

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Sentences [show]
No. Sentence Comment
47 The CF diagnosis was confirmed by CFTR molecular analysis, with a genotype as follows: p.[Phe508del] ϩ [Leu167Arg]. Login to comment
95 Results Defective Activation and Maturation of L102P and L167R CFTR Mutants Details of the six patients, their genotypes and phenotypes, and characteristics of their CFTR mutations are provided (Table 2). Login to comment
97 Sequences of Site-Directed Mutagenesis Primers Mutation Sense oligonucleotide sequences L102P 5=-GTACAGCCTCTCTTACCGGGAAGAATCATAGCTTCC-3= L167R 5=-AAGAAGACTTTAAAGCGGTCAAGCCGTGTTCTAG-3= P574S 5=-GCTGATTTGTATTTATTAGACTCTTCTTTTGGATACCTAGATG-3= V562I 5=-AGAATTTCTTTAGCAAGAGCAATATACAAAGATGCTGATTTG-3= K696R 5=-CAGACTGGAGAGTTTGGGGAAAGAAGGAAGAATTCTATTCTC-3= P841R 5=-GATATGGAGAGCATACGAGCAGTGACTACATGG-3= CFTR Missense Mutation Biological Assay 3 JMD Month 2011, Vol. xx, No. Login to comment
98 x 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 AQ: 15 AQ: 16 AQ:17-18 AQ: 19 AQ: 20 T1 AQ: 21 AQ: 22 AQ: 23 AQ: 24 AQ: 25 AQ: 26 AQ: 27 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 AQ: 28 AQ: 29 AQ: 30 T2 variants that we investigate herein, two affect membrane-spanning domain 1: p.[Leu102Pro] (L102P) and p.[Leu167Arg] (L167R). Login to comment
100 Thus, L102P and L167R mutants appear unable to escape the ER. Login to comment
104 Although 100% activation is attributed to the maximal activation peak of WT-CFTR, activation is reduced to 7.45% Ϯ 3.76% (n ϭ 4) for L102P and to 27.84% Ϯ 1.96% (n ϭ 4) for L167R. Login to comment
122 Summary of the Patients` Data, Concerning Genotype, Phenotype, and Protein Dysfunction Patient no./sex/age at molecular diagnostics (years) Genotype Phenotype Protein dysfunctions Channel activity* Maturation† Intracellular localization‡ 1/F/3 p.[Leu102Pro] ϩ [Arg553X] Positive sweat test result, bacterial lung colonization, no pancreatitis ϩϩ ϩϩ ϩϩ 2/F/newborn p.[Phe508del] ϩ [Leu167Arg] Positive sweat test result, recurrent pancreatitis, no lung infection ϩϩ ϩϩ ϩϩ 3/F/3 p.[Asn1303Lys] ϩ [Pro574Ser] Normal sweat test result, asymptomatic ϩϩ ϩ ϩ 4/M/31 p.[Arg74Trp;Val201Met; Asp1270Asn] ϩ [Pro841Arg]; c. Login to comment
133 After using Western blot analysis (Figure 3B), the proportions of core-glycosylated protein for K696R and P841R appear insignificantly different from that of WT-CFTR (n ϭ 3, data not shown). Login to comment
134 Moreover, we observe by iodide efflux experiments that both mutations have similar functional consequence on CFTR activity: the maximum activation is reduced to 49.67% Ϯ 2.61% (n ϭ 4) for K696R and to 45.10% Ϯ 4.94% (n ϭ 4) for P841R (Figure 3C). Login to comment
151 In our model, two missense mutations, L102P and A calreticulin egremP201L calreticulin egremP201L L167R calreticulin mergeL167R calreticulin merge CB F508del L102P L167R WT F508del L102P L167R *** *** ***WT + inh172 L102P L167R *** *** ***WT + inh172 L102P L167R B C CFTR B C CFTR % of maximal activation C. Login to comment
154 L102P and L167R amino acid substitutions impair CFTR protein maturation. Login to comment
169 x 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 F4 C O L O R 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 AQ: 33 F5 C O L O R L167R, exhibit an F508del-like phenotype: the proteins are blocked at the ER level, and their absence at the plasma membrane elicits reduced channel activity. Login to comment
174 Another patient, with chronic sinusitis and pancreatic failure, has the genotype p.[Leu167Arg] ϩ [Phe508del]. Login to comment
175 The L167R allele exhibits, as described for L102P, a maturation and trafficking defect leading to a sharp decrease of CFTR activity compared with that of WT-CFTR. Login to comment
176 Nevertheless, iodide efflux experiments on L167R exhibit a residual activity slightly more elevated (27.84%) than that for L102P (7.45%). Login to comment
183 Contrary to L102P and L167R, P574S is not fully retained in the ER compartment because we can see the presence of the fully glycosylated mature form of CFTR by using Western blot analysis. Login to comment
184 This observation is sustained by confocal microscopic imaging clearly showing different staining patterns for P574S- CFTR and the ER resident calreticulin. Login to comment
185 Taken together, these results strengthen the idea that a small part of P574S could reach post-Golgi compartments and, thus, the plasma membrane. Login to comment
193 K696R and P841R amino acid substitutions affect CFTR channel activity. Login to comment
60 Sequences of Site-Directed Mutagenesis Primers Mutation Sense oligonucleotide sequences L102P 5=-GTACAGCCTCTCTTACCGGGAAGAATCATAGCTTCC-3= L167R 5=-AAGAAGACTTTAAAGCGGTCAAGCCGTGTTCTAG-3= P574S 5=-GCTGATTTGTATTTATTAGACTCTTCTTTTGGATACCTAGATG-3= V562I 5=-AGAATTTCTTTAGCAAGAGCAATATACAAAGATGCTGATTTG-3= K696R 5=-CAGACTGGAGAGTTTGGGGAAAGAAGGAAGAATTCTATTCTC-3= P841R 5=-GATATGGAGAGCATACGAGCAGTGACTACATGG-3= was presented. Login to comment
72 A calreticulin egremP201L calreticulin egremP201L L167R calreticulin mergeL167R calreticulin merge CB F508del L102P L167R WT F508del L102P L167R *** *** ***WT + inh172 L102P L167R *** *** ***WT + inh172 L102P L167R B C CFTR B C CFTR % of maximal activation 0 50 100 WT 0 50 100 WTNaKATPaseNaKATPase Figure 1. Login to comment
73 L102P and L167R amino acid substitutions impair CFTR protein maturation. Login to comment
81 Summary of the Patients` Data, Concerning Genotype, Phenotype, and Protein Dysfunction Patient no./sex/age at molecular diagnostics (years) Genotype Phenotype Protein dysfunctions Channel activity* Maturation† Intracellular localization‡ 1/F/3 p.[Leu102Pro] ϩ [Arg553X] Positive sweat test result, bacterial lung colonization, no pancreatitis ϩϩ ϩϩ ϩϩ 2/F/newborn p.[Phe508del] ϩ [Leu167Arg] Positive sweat test result, recurrent pancreatitis, no lung infection ϩϩ ϩϩ ϩϩ 3/F/3 p.[Asn1303Lys] ϩ [Pro574Ser] Normal sweat test result, asymptomatic ϩϩ ϩ ϩ 4/M/31 p.[Arg74Trp;Val201Met; Asp1270Asn] ϩ [Pro841Arg]; c. Login to comment
136 Thus, L102P and L167R mutants appear unable to escape the ER. Login to comment
140 When 100% activation is attributed to the maximal activation peak of WT-CFTR, activation is reduced to 7.45% Ϯ 3.76% (n ϭ 4) for L102P and to 27.84% Ϯ 1.96% (n ϭ 4) for L167R. Login to comment
179 In our model, two missense mutations, L102P and L167R, exhibit an F508del-like phenotype: the proteins are blocked at the ER level, and their absence at the plasma membrane elicits reduced channel activity. Login to comment
186 Nevertheless, iodide efflux experiments on L167R exhibit a residual activity slightly more elevated (27.84%) than that for L102P (7.45%). Login to comment