OBJECTIVE: The aim of the study was to search for mutations of SCNN1B and SCNN1G in an Italian family with apparently dominant autosomal transmission of a clinical phenotype consistent with Liddle's syndrome. METHODS: Genetic analysis was performed in the proband, his relatives, and 100 control subjects. To determine the functional role of the mutation identified in the proband, we expressed the mutant or wild-type epithelial sodium channel in Xenopus laevis oocytes. RESULTS: A novel point mutation, causing an expected substitution of a leucine residue for the second proline residue of the conserved PY motif (PPP x Y) of the beta subunit was identified in the proband. The functional expression of the mutant epithelial sodium channel in X. laevis oocytes showed a three-fold increase in the amiloride-sensitive current as compared with that of the wild-type channel. CONCLUSION: This newly identified mutation adds to other missense mutations of the PY motif of the beta subunit of the epithelial sodium channel, thus confirming its crucial role in the regulation of the epithelial sodium channel. To our knowledge, this is the first report of Liddle's syndrome in the Italian population, confirmed by genetic and functional analysis, with the identification of a gain-of-function mutation not previously reported.
OBJECTIVE: The aim of the study was to search for mutations of SCNN1B and SCNN1G in an Italian family with apparently dominant autosomal transmission of a clinical phenotype consistent with Liddle's syndrome. METHODS: Genetic analysis was performed in the proband, his relatives, and 100 control subjects. To determine the functional role of the mutation identified in the proband, we expressed the mutant or wild-type epithelial sodium channel in Xenopus laevis oocytes. RESULTS: A novel point mutation, causing an expected substitution of a leucine residue for the second proline residue of the conserved PY motif (PPP x Y) of the beta subunit was identified in the proband. The functional expression of the mutant epithelial sodium channel in X. laevis oocytes showed a three-fold increase in the amiloride-sensitive current as compared with that of the wild-type channel. CONCLUSION: This newly identified mutation adds to other missense mutations of the PY motif of the beta subunit of the epithelial sodium channel, thus confirming its crucial role in the regulation of the epithelial sodium channel. To our knowledge, this is the first report of Liddle's syndrome in the Italian population, confirmed by genetic and functional analysis, with the identification of a gain-of-function mutation not previously reported.
Authors: Rebecca A Chanoux; Amal Robay; Calla B Shubin; Catherine Kebler; Laurence Suaud; Ronald C Rubenstein Journal: J Biol Chem Date: 2012-04-10 Impact factor: 5.157
Authors: Rebecca A Chanoux; Calla B Shubin; Amal Robay; Laurence Suaud; Ronald C Rubenstein Journal: Am J Physiol Cell Physiol Date: 2013-07-24 Impact factor: 4.249
Authors: May E Montasser; Donfeng Gu; Jing Chen; Lawrence C Shimmin; Charles Gu; Tanika N Kelly; Cashell E Jaquish; Treva Rice; Dabeeru C Rao; Jie Cao; Jichun Chen; De-Pei Liu; Paul K Whelton; Jiang He; James E Hixson Journal: Am J Hypertens Date: 2011-06-09 Impact factor: 2.689
Authors: Qi Zhao; Dongfeng Gu; James E Hixson; De-Pei Liu; Dabeeru C Rao; Cashell E Jaquish; Tanika N Kelly; Fanghong Lu; Jixiang Ma; Jianjun Mu; Lawrence C Shimmin; Jichun Chen; Hao Mei; L Lee Hamm; Jiang He Journal: Circ Cardiovasc Genet Date: 2011-05-11
Authors: Xueli Yang; Jiang He; Dongfeng Gu; James E Hixson; Jianfeng Huang; Dabeeru C Rao; Lawrence C Shimmin; Jichun Chen; Treva K Rice; Jianxin Li; Karen Schwander; Tanika N Kelly Journal: Am J Hypertens Date: 2014-04-15 Impact factor: 2.689