GCaMP imaging reports neuronal activity.

A) Expression pattern of GCamP5 using the RRa-Gal4 driver line. Paired aCC neurons (solid arrow) show clear segmental expression whilst RP2 neurons (dashed arrow) show weaker expression and only in some segments. B) Sample recording of simultaneous loose-patch (lower trace) and calcium-imaging (upper trace) of the same aCC motoneuron. C) Spike count from loose-patch recordings of aCC neurons plotted against the area under the curve (AUC) of calcium-imaging from the same motoneuron (accumulated data from n = 5). The line of fit shown has an R2 = 0.572.