Changing Hearts

Every beat of your heart is tightly controlled by special pacemaker cells that emit waves of electrical signals across your heart. These signals raise calcium levels in heart cells, causing them to contract. With limits in microscopy, studying this has often involved removing the heart from an animal. Researchers now use zebrafish to study this in vivo using live 3D imaging. Zebrafish were genetically altered to express a dye in their heart cells that fluoresces when calcium levels rise. The team imaged and modelled the changing shape of the developing zebrafish heart (pictured, clockwise from top left) over the course of 300 milliseconds (pink, purple, blue, green, yellow and orange corresponding to 50 millisecond chunks of time). The rising calcium levels spread across the heart at different speeds according to differences in its anatomy. This approach allows the simultaneous study of whole organ and cell level changes during heart development.

Written by Lux Fatimathas

Lux Fatimathas

Writer

Having pursued science through a career in research, communications and publishing, she is currently a writer and editor for a healthcare marketing agency and also juggles freelance science writing.

• Image from work by Michael Weber and Nico Scherf, and colleagues
• Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
• Image originally published under a Creative Commons Licence (BY 4.0)
• Published in eLife, December 2017