Visually guided behaviours in Zebrafish larvae and the role of Fmn2b

Abstract

Larval Zebrafish respond to visual stimuli with eye saccades and tail flicks, which depend on the features of the stimuli. Any deficit in these responses indicates a possible defect in visual processing. Studies in the lab have shown that fmn2bΔ7/Δ7 mutant zebrafish larvae have defects in the visual system. We also found deficits in the optomotor response of fmn2bΔ7/Δ7 zebrafish larvae, thus indicating the potential role of Fmn2b in visually guided behaviours. A robust way of stimuli presentation, behaviour recording, and downstream analysis are required to dissect the role of any protein in behaviour. Using an Arduino UNO microcontroller, we designed a platform to perform visually guided behaviour in a partially restrained zebrafish larva, which includes an automatic stimulus presentation unit connected with a high-speed video recording unit- StimUNO. We also developed an automatic pipeline for tracking larval movements, which is flexible and can be adapted to any experimental questions. The reliability of StimUNO and our data analysis pipeline was tested on various behaviours like the looming disc evoked escape response, optokinetic response and virtual prey hunting response. We propose this as a valuable tool in studying the processing of sensory stimuli in larval zebrafish