Abdelfattah, A.S. et al. Science 365, 699–704 (2019)

Genetically encoded voltage indicators, or GEVIs, are a means to image fast neuronal activity in the brain. As different neurons fire, voltage-sensitive dyes detect that change and light up in response. These have been common for some time, but many can leave a little resolution to be desired. A new tool, dubbed ‘Voltron’ by its creators at the Howard Hughes Medical Institute, adds additional detail.

Voltron pairs a protein genetically encoded in individual neurons in vivo with a synthetic dye that is brighter and lasts longer than other fluorescent protein-based GEVIs. Writing in Science, the team demonstrates Voltron at work in real time in mice, larval zebrafish, and Drosophila. The tool is currently compatible with conventional and light-sheet microscopes.