PUBLICATION

Zebrafish model for human long QT syndrome

Authors
Arnaout, R., Ferrer, T., Huisken, J., Spitzer, K., Stainier, D.Y., Tristani-Firouzi, M., and Chi, N.C.
ID
ZDB-PUB-070711-4
Date
2007
Source
Proceedings of the National Academy of Sciences of the United States of America   104(27): 11316-11321 (Journal)
Registered Authors
Chi, Neil C., Huisken, Jan, Stainier, Didier
Keywords
cardiac, development, kcnh2, arrhythmia, electrophysiology
MeSH Terms
  • Action Potentials/genetics
  • Amino Acid Substitution/genetics
  • Animals
  • Disease Models, Animal*
  • Electrocardiography
  • Ether-A-Go-Go Potassium Channels
  • Heart Arrest/genetics
  • Heart Arrest/physiopathology
  • Humans
  • Long QT Syndrome/embryology
  • Long QT Syndrome/genetics*
  • Long QT Syndrome/physiopathology
  • Phenotype
  • Potassium Channels, Voltage-Gated/genetics
  • Xenopus
  • Zebrafish/embryology
  • Zebrafish/genetics*
  • Zebrafish/physiology
PubMed
17592134 Full text @ Proc. Natl. Acad. Sci. USA
Abstract
Long QT syndrome (LQTS) is a disorder of ventricular repolarization that predisposes affected individuals to lethal cardiac arrhythmias. To date, an appropriate animal model of inherited LQTS does not exist. The zebrafish is a powerful vertebrate model used to dissect molecular pathways of cardiovascular development and disease. Because fundamental electrical properties of the zebrafish heart are remarkably similar to those of the human heart, the zebrafish may be an appropriate model for studying human inherited arrhythmias. Here we describe the molecular, cellular, and electrophysiological basis of a zebrafish mutant characterized by ventricular asystole. Genetic mapping and direct sequencing identify the affected gene as kcnh2, which encodes the channel responsible for the rapidly activating delayed rectifier K(+) current (I(Kr)). We show that complete loss of functional I(Kr) in embryonic hearts leads to ventricular cell membrane depolarization, inability to generate action potentials (APs), and disrupted calcium release. A small hyperpolarizing current restores spontaneous APs, implying wild-type function of other ionic currents critical for AP generation. Heterozygous fish manifest overt cellular and electrocardiographic evidence for delayed ventricular repolarization. Our findings provide insight into the pathogenesis of homozygous kcnh2 mutations and expand the use of zebrafish mutants as a model system to study human arrhythmias.
Genes / Markers
Figures
Show all Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping