Light Spot Assay: een methode om drosophila-fototactisch gedrag te onderzoeken

- Begin by selecting a third instar larva, the largest of the larval forms, from the culture medium, and wash it with water to remove any food. Since the larval eyes, or Bolwig organs, are located in the upper front of the larva, place the larva in the center of an agar plate with the light source above the animal. Turn off the room light and allow the larva to acclimate to the dark.

Since the larva is barely detectable in a light spot made by visible light, turn on infrared LED lights to illuminate the animal for the camera. Wait until the animal begins crawling straight to control for its path. And then rotate the plate so that the larva crawls directly toward the light spot. Record the animal crawling into the light and then away from the light spot. This light-avoidance tactic helps larvae avoid predators by burrowing into food.

In the following example, we will perform the light spot assay to test the ability of different genetic strains of Drosophila larvae to escape light.

- Before introducing the larva to the imaging setup, acquire a short video of the light position, and name the unfiltered control background video "lightarea1". Place the filter back on the camera lens, an