Functional effects of KCNE3 mutation and its role in the development of Brugada syndrome

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningfagfællebedømt

  • Eva Delpón
  • Jonathan M Cordeiro
  • Lucía Núñez
  • Poul Erik Bloch Thomsen
  • Alejandra Guerchicoff
  • Guido D Pollevick
  • Yuesheng Wu
  • Kanters, Jørgen K.
  • Carsten Toftager Larsen
  • H. Jacob Peider Hofman-Bang
  • Elena Burashnikov
  • Michael Christiansen
  • Charles Antzelevitch
INTRODUCTION: The Brugada Syndrome (BrS), an inherited syndrome associated with a high incidence of sudden cardiac arrest, has been linked to mutations in four different genes leading to a loss of function in sodium and calcium channel activity. Although the transient outward current (I(to)) is thought to play a prominent role in the expression of the syndrome, mutations in I(to)-related genes have not been identified as yet. METHODS AND RESULTS: One hundred and five probands with BrS were screened for ion channel gene mutations using single strand conformation polymorphism (SSCP) electrophoresis and direct sequencing. A missense mutation (R99H) in KCNE3 (MiRP2) was detected in one proband. The R99H mutation was found 4/4 phenotype positive and 0/3 phenotype-negative family members. Chinese hamster ovary (CHO)-K1 cells were co-transfected using wild-type (WT) or mutant KCNE3 and either WT KCND3 or KCNQ1. Whole-cell patch clamp studies were performed after 48 hours. Interactions between Kv4.3 and KCNE3 were analyzed in co-immunoprecipitation experiments in human atrial samples. Co-transfection of R99H-KCNE3 with KCNQ1 produced no alteration in current magnitude or kinetics. However, co-transfection of R99H KCNE3 with KCND3 resulted in a significant increase in the I(to) intensity compared to WT KCNE3+KCND3. Using tissues isolated from left atrial appendages of human hearts, we also demonstrate that K(v)4.3 and KCNE3 can be co-immunoprecipitated. CONCLUSIONS: These results provide definitive evidence for a functional role of KCNE3 in the modulation of I(to) in the human heart and suggest that mutations in KCNE3 can underlie the development of BrS
Udgivelsesdato: 2008
TidsskriftCirculation. Arrhythmia and Electrophysiology
Udgave nummer3
Sider (fra-til)209-218
Antal sider10
StatusUdgivet - 2008

ID: 10913052