Development of a Patient-Derived Induced Pluripotent Stem Cell Model for the Investigation of SCN5A-D1275N-Related Cardiac Sodium Channelopathy.
Circ J
; 81(12): 1783-1791, 2017 Nov 24.
Article
em En
| MEDLINE
| ID: mdl-28637969
ABSTRACT
BACKGROUND:
TheSCN5Agene encodes the α subunit of the cardiac voltage-gated sodium channel, NaV1.5. The missense mutation, D1275N, has been associated with a range of unusual phenotypes associated with reduced NaV1.5 function, including cardiac conduction disease and dilated cardiomyopathy. Curiously, the reported biophysical properties ofSCN5A-D1275N channels vary with experimental system.MethodsâandâResults:
First, using a human embryonic kidney (HEK) 293 cell-based heterologous expression system, theSCN5A-D1275N channels showed similar maximum sodium conductance but a significantly depolarizing shift of activation gate (+10 mV) compared to wild type. Second, we generated human-induced pluripotent stem cells (hiPSCs) from a 24-year-old female who carried heterozygousSCN5A-D1275N and analyzed the differentiated cardiomyocytes (CMs). AlthoughSCN5Atranscript levels were equivalent between D1275N and control hiPSC-CMs, both the total amount of NaV1.5 and the membrane fractions were reduced approximately half in the D1275N cells, which were rescued by the proteasome inhibitor MG132 treatment. Electrophysiological assays revealed that maximum sodium conductance was reduced to approximately half of that in control hiPSC-CMs in the D1275N cells, and maximum upstroke velocity of action potential was lower in D1275N, which was consistent with the reduced protein level of NaV1.5.CONCLUSIONS:
This study successfully demonstrated diminished sodium currents resulting from lower NaV1.5 protein levels, which is dependent on proteasomal degradation, using a hiPSC-based model forSCN5A-D1275N-related sodium channelopathy.Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Mutação de Sentido Incorreto
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Canalopatias
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Células-Tronco Pluripotentes Induzidas
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Canal de Sódio Disparado por Voltagem NAV1.5
Limite:
Humans
Idioma:
En
Revista:
Circ J
Assunto da revista:
ANGIOLOGIA
/
CARDIOLOGIA
Ano de publicação:
2017
Tipo de documento:
Article