Exploring Bioelectricity with Ace2N-mNeon during Zebrafish Embryogenesis

Bioelectricity is a fundamental biophysical phenomenon present in all cells, playing a crucial role in embryogenesis by regulating processes such as neuronal signaling, pattern formation, and cancer suppression. Precise monitoring of bioelectric signals and their dynamic changes throughout development is vital for advancing our understanding of higher organisms. However, the lack of suitable techniques for mapping bioelectric signals during early development has greatly limited our ability to interpret these mechanisms. To address this challenge, we developed an Ace2N-mNeon expression library in zebrafish, which exhibits membrane localization from 4 hours post-fertilization to at least 5 days post- fertilization and broad expression across multiple cell types throughout development. We validated the use of this library for studying bioelectric changes via voltage imaging to record signals in neurons and cardiomyocytes at different development stages. Through this approach, we found evidence of synchronized neuronal activity during early embryogenesis and observed faster voltage dynamics in cardiomyocytes as development progressed. Our results show that the Ace2N-mNeon library is a valuable tool for developmental bioelectric studies supporting advanced techniques such as voltage imaging and fluorescence lifetime imaging (FLIM). These methods enable non-invasive, dynamic monitoring of bioelectric signals across diverse cell types throughout development, significantly surpassing the capabilities of current electrophysiological techniques.