Liddle syndrome caused by P616R mutation of the epithelial sodium channel β subunit

Liddle's syndrome caused by a novel missense mutation (P617L) of the epithelial sodium channel β subunit

“…Genetic analysis of patients with Liddle's syndrome has so far identified 13 mutations in bENaC [7][8][9][10][11][12][13][14]16,[18][19][20][21][22][23][24][25][26] and four in gENaC [14][15][16][17]. These are either gross deletion, nonsense, or frameshift mutations in the b or g subunits that abrogate the PY-motif [7][8][9][10][11][12][13][14][15][16][17], as well as missense mutations that change the PY-motif in the Cterminal end of the b subunit of ENaC [16,[18][19][20][21][22][23][24][25][26].…”

“…This channel is composed of three homologous subunits, a, b and g. Each subunit consists of two transmembrane domains, a large extracellular loop, and short cytoplasmic amino and carboxyl termini [4][5][6]. Most identified mutations causing Liddle's syndrome delete a conserved proline-rich PY motif (PPP Â Y) in the cytoplasmic C-terminus region of the b [7][8][9][10][11][12][13][14] or g subunits [15][16][17] of EnaC, or alter the same PY motif in the C-terminus of the b subunit [16,[18][19][20][21][22][23][24][25][26], resulting in increased ENaC activity.…”

A Clinical Phenotype Mimicking Essential Hypertension in a Newly Discovered Family With Liddle's Syndrome

“…original contributions Normokalemic Liddle's Syndrome same PY motif in the C-terminus of β-subunit, 16,[18][19][20][21][22][23][24][25][26][27][28] resulting in increased ENaC activity. These PY motifs mediate an inhibitory regulation of ENaC apical expression, which occurs in physiological conditions characterized by low-suppressed secretion of aldosterone.…”

Whole-exome sequencing reveals an inherited R566X mutation of the epithelial sodium channel β-subunit in a case of early-onset phenotype of Liddle syndrome

“…However, we present an early-onset case in a 5-yr-old girl with a p.Arg566* mutation of the epithelial sodium channel β-subunit. Other mutations reported in Liddle syndrome that delete or alter a conserved proline-rich amino acid sequence, PY motif, have been reported in childhood or adolescent cases and include P616L missense mutation in an 8-yr-old Czech boy (Ciechanowicz et al 2005) and a 13-yr-old Serbian boy (Bogdanovic et al 2012) and a Y618H mutation in a 4-yr-old Afro-Haitian girl (Freundlich and Ludwig 2005). …”