RT Journal Article
T1 p.D1690N Nav1.5 rescues p.G1748D mutation gating defects in a compound heterozygous Brugada syndrome patient
A1 Núñez Fernández, Lucía
A1 Barana Muñoz, Adriana
A1 Amorós García, Irene
A1 González de la Fuente, Marta
A1 Dolz Gaitón, Pablo
A1 Gómez García, Ricardo
A1 Rodríguez García, Isabel
A1 Mosquera, Ignacio
A1 Monserrat, Lorenzo
A1 Delpón Mosquera, María Eva
A1 Caballero Collado, Ricardo
A1 Castro Beirás, Alfonso
A1 Tamargo Menéndez, Juan
AB Background: We identified 2 compound heterozygous mutations (p.D1690N and p.G1748D) in the SCN5A gene encoding cardiac Na(+) channels (Nav1.5) in a proband diagnosed with Brugada syndrome type 1. Furthermore, in the allele encoding the p.D1690N mutation, the p.H558R polymorphism was also detected.Objective: The purpose of this study was to analyze the functional properties of the mutated channels as well as the putative modulator effects produced by the presence of the polymorphism.Methods: Wild-type and mutated human Nav1.5 channels were expressed in Chinese hamster ovary cells and recorded using whole-cell patch-clamp technique.Results: Separately, both p.D1690N and p.G1748D mutations produced a marked reduction in peak Na(+) current density (>80%), mainly due to their limited trafficking toward the membrane. Furthermore, p.G1748D mutation profoundly affected channel gating. Both p.D1690N and p.G1748D produced a marked dominant negative effect when cotransfected with either wild-type or p.H558R channels. Conversely, p.H558R was able to rescue defective trafficking of p.D1690N channels toward the membrane when both polymorphism and mutation were in the same construct. Surprisingly, cotransfection with p.D1690N, either alone or together with the polymorphism (p.H558R-D1690N), completely restored the profound gating defects exhibited by p.G1748D channels but only slightly rescued their trafficking.Conclusions: Our results add further support to the hypothesis that Nav1.5 subunits interact among them before trafficking toward the membrane and suggest that a missense mutation can "rescue" the defective gating produced by another missense mutation.
PB Elsevier
SN 0014-2972
YR 2013
FD 2013-02-01
LK https://hdl.handle.net/20.500.14352/100149
UL https://hdl.handle.net/20.500.14352/100149
LA eng
NO Núñez L, Barana A, Amorós I, de la Fuente MG, Dolz-Gaitón P, Gómez R, Rodríguez-García I, Mosquera I, Monserrat L, Delpón E, Caballero R, Castro-Beiras A, Tamargo J. p.D1690N Nav1.5 rescues p.G1748D mutation gating defects in a compound heterozygous Brugada syndrome patient. Heart Rhythm. 2013 Feb;10(2):264-72. doi: 10.1016/j.hrthm.2012.10.025
DS Docta Complutense
RD 17 abr 2025