PUBLICATION

Mapping Calcium Dynamics in the Heart of Zebrafish Embryos with Ratiometric Genetically Encoded Calcium Indicators

Authors
Salgado-Almario, J., Vicente, M., Vincent, P., Domingo, B., Llopis, J.
ID
ZDB-PUB-201002-50
Date
2020
Source
International Journal of Molecular Sciences   21(18): (Journal)
Registered Authors
Domingo Moreno, Beatriz, Llopis, Juan Francisco, Vicente Ruiz, Manuel
Keywords
biosensor, calcium, embryo, genetically encoded calcium indicator (GECI), heart, imaging, zebrafish
MeSH Terms
  • Animals
  • Animals, Genetically Modified
  • Biosensing Techniques*
  • Calcium/analysis*
  • Calcium/metabolism
  • Embryo, Nonmammalian/metabolism
  • Fluorescent Dyes*
  • Myocardium/metabolism*
  • Zebrafish/genetics*
  • Zebrafish/metabolism
PubMed
32927644 Full text @ Int. J. Mol. Sci.
Abstract
Zebrafish embryos have been proposed as a cost-effective vertebrate model to study heart function. Many fluorescent genetically encoded Ca2+ indicators (GECIs) have been developed, but those with ratiometric readout seem more appropriate to image a moving organ such as the heart. Four ratiometric GECIs based on troponin C, TN-XXL, Twitch-1, Twitch-2B, and Twitch-4 were expressed transiently in the heart of zebrafish embryos. Their emission ratio reported the Ca2+ levels in both the atrium and the ventricle. We measured several kinetic parameters of the Ca2+ transients: systolic and diastolic ratio, the amplitude of the systolic Ca2+ rise, the heart rate, as well as the rise and decay times and slopes. The systolic ratio change decreased in cells expressing high biosensor concentration, possibly caused by Ca2+ buffering. The GECIs were able to report the effect of nifedipine and propranolol on the heart, which resulted in changes in heart rate, diastolic and systolic Ca2+ levels, and Ca2+ kinetics. As a result, Twitch-1 and Twitch-4 (Kd 0.25 and 2.8 µM, respectively) seem the most promising GECIs for generating transgenic zebrafish lines, which could be used for modeling heart disorders, for drug screening, and for cardiotoxicity assessment during drug development.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping