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Objective The pretectum, a region between the thalamus and midbrain, receives binocular sensory inputs from retinal ganglion ceils (RGCs) and sends output to the optic tectum.Many studies in amphibians suggest important roles of the pretectum in prey capture behavior.Zebrafish larvae develop the ability to capture prey as early as 5 days post-fertilization (dpf).Zebrafish pretectum mainly consists of three types of neurons, including dopaminergic, serotoninergic and GABAergic cells, implying its modulatory roles in prey capture.In present study, we examined how the pretectum regulates prey capture at both neural circuit and behavior levels.Methods The morphology of pretectal dopaminergic neurons was revealed by using the transgenic line ETvmat2:GFP, in which monoaminergic neurons express GFP, and Kaede-based photo-conversion in vivo imaging.Then, defects in the paramecium capture behavior of zebrafish larvae with laser ablation of pretectal dopaminergic neurons were examined.Then, in vivo calcium imaging of both tectal and pretectal neurons was carried on to study their response evoked by prey-like cues.Finally, the detection of dopamine release by carbon fiber and pharmacological manipulation of dopamine signaling were used to examine the role of dopaminergic neurons in modulation of optic tectal functions.Results We found that there was a dopaminergic neuron cluster in the pretectum that projected to the deep layer of the tectal neuropil.Focal ablation of these neurons impaired paramecium capture behavior.Preliminary data showed that some sparsely distributed tectal neurons responded to prey-like visual stimuli.Further experiments will be performed to figure out how pretectal dopaminergic neurons modulate prey-like cue-induced responses in tectal neurons.Conclusion The pretectum regulates prey capture behavior through dopaminergic neuromodulation of tectal function.