Larval Fillet Preparation: A Method to Visualize Intact Sensory Neurons and Associated Epidermal Cells

- To orient a larva for fillet dissection, place it in a silicone-coated dish containing cold saline and identify its dorsal and ventral sides. Tracheal tubes running along its length mark the dorsal side, while abdominal denticle belts identify the ventral side.

Then, with the ventral side up, gently stretch the larva and pin each end to the bottom of the dish. This position will keep the dorsal clusters of sensory multi-dendritic neurons and the associated epidermal cells intact as the dissection proceeds.

Use dissecting scissors to cut along the ventral midline of the larva. Pin the cuticle to the plate to flatten the preparation and remove internal structures to reveal the underlying muscle tissue. Then, carefully remove the appropriate muscle to expose the epidermis and gain access to previously obscured neurons while preserving their dendritic morphology.

In the example protocol, we will see a detailed demonstration of larval fillet preparation and muscle removal to view sensory da neurons and epidermal cells.

- To begin, add enough cold saline to a silicone elastomer dish to cover the bottom surface. Add the subject larva to the dish and place it under the stereo microscope,