Extended Data Fig. 1: Sustained CDN activity is necessary and sufficient to end matings.
From: Dopamine biases decisions by limiting temporal integration
(a) Left: Individual CDNs labelled via MultiColor FlpOut48 (image of a single optical section of the abdominal ganglion). Right: CDN dendrites selectively cover the midline tracts of the abdominal ganglion (blue); the CDNs send axonal projections throughout the abdominal ganglion (magenta). Scale bars are 20 μm. (b) Electrical activity of the CDNs is only necessary around the time of termination to end the mating: silencing that begins just before the natural time of termination (20 min) is still sufficient to prolong the mating –5 flies stopped mating before the light was turned on. (c) Optogenetic stimulation of the CDNs using CsChrimson preceding the onset of mating does not affect copulation duration if only supplied during courtship (brown), but shortens copulation by several minutes if continued into the mating (flashing red light throughout the duration of the experiment, “tonic”, red). These results closely resemble the results of thermogenetic activation in previous work1 that did find immediate termination of the mating upon CDN activation. Providing the same optogenetic activation only after mating begins results in near-immediate termination of copulation (blue). (d) Flies end matings in response to 2 seconds of optogenetic CDN stimulation with varying latencies. Left: ethogram, right: cumulative distribution plot. (e) Stimulation of the CDNs followed by immediate electrical silencing largely prevents the termination of matings that had not ended before the silencing began. Left: ethogram, right: cumulative distribution plot. (f) Mating with a heat-insensitive, Gr28b.d;TrpA1 double mutant female does not change the male’s decision to stop mating when threatened by heat.
