The lack of physiological recordings from Caenorhabditis elegans
embryos stands in stark contrast to the comprehensive anatomical and gene
expression datasets already available. Using light-sheet fluorescence
microscopy (LSFM) to address the challenges associated with functional
imaging at this developmental stage, we recorded calcium dynamics in
muscles and neurons and developed analysis strategies to relate activity and
movement. In muscles, we found that the initiation of twitching was
associated with a spreading calcium wave in a dorsal muscle bundle.
Correlated activity in muscle bundles was linked with early twitching and
eventual coordinated movement. To identify neuronal correlates of behavior,
we monitored brain-wide activity with subcellular resolution and identified a
particularly active cell associated with muscle contractions. Finally, imaging
neurons of a well-defined adult motor circuit, we found that reversals in the
eggshell correlated with calcium transients in AVA interneurons.
