Fig. 1
Activity in the ILH in the presence of prey. (a) UAS:EGFP reporter gene expression in the ILH in hspGFFDMC76A Gal4 fish at 5 d.p.f. The left ILH is encircled by dotted lines. ILH: the inferior lobe of the hypothalamus, POA: preoptic area. Scale bar, 50 μm. (b) ILH activation during prey capture behaviour in a previously unfed 4 d.p.f. larva. Selected frames from a time-lapse fluorescent microscopy movie of UAShspzGCaMP6s; hspGFFDMC76A larvae. Inset: F/F0 in pseudo-colours. Scale bar: 500 μm. (c) Normalized GCaMP6s fluorescence intensity (F/F0) from the recording shown in b. (d) ILH activity in the presence of a paramecium in a 5 d.p.f. zebrafish larva that was embedded in agarose. The trajectories of a single paramecium over 149 s are shown with the colour-coded changes in the intensity of the GCaMP6s fluorescence in the ILH. The signals in the left and right ILH were averaged. The length of the arrowhead indicates the distance travelled by the paramecium in 120 ms. Scale bar, 1 mm. (e) ILH activity (GCaMP6s fluorescence intensity, F/F0) in response to a moving spot on a screen. (Mean (thick line)±s.e.m. (thin dotted lines), n=5 larvae). The signals measured in the left and right ILH were averaged. A moving spot of 2.4° in diameter was presented to the larva at a speed of 100 deg s−1 from 0 to 3.1 s. (f) Paramecium consumption in UAS:zBoTxBLCGFP; hspGFFDMC76A larvae (n=6, magenta), control larvae (UAS:zBoTxBLCGFP alone) (n=18, blue), and wild-type control larvae (n=13, black). The number of the paramecia left in the chamber was normalized to the initial count. The thick lines represent the mean and the thin dotted lines represent the s.d. The asterisk indicates a significant difference between the toxin:Gal4 double transgenic larvae and UAS:zBoTxBLCGFP alone control larvae at 10 min (one-tailed t-test, P=0.040). |