Gαq splice variants mediate phototransduction, rhodopsin synthesis, and retinal integrity in Drosophila

Protocol for electron microscopy of Drosophila photoreceptor cells

In Drosophila, mutations in genes that prevent normal Ca²⁺ influx after light stimulation usually cause light-dependent retinal degeneration or neurodegeneration, detectable by defects in eye morphology. Here, we present a protocol based on electron microscopy (EM) to observe the morphological structure of photoreceptor cells in Drosophila. We detail how to fix, dehydrate, embed, and polymerize compound eye samples, followed by sectioning, post-staining, and image acquisition, to assess the eye morphology at the ultrastructural level.

For complete details on the use and execution of this protocol, please refer to Gu et al. (2020).

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A protocol for revealing the ultrastructure of Drosophila photoreceptor cells

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Preparing compound eye samples for electron microscope observation

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Dissecting molecular mechanisms underlying retinal degeneration

Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.

Protocol for electroretinogram recording of the Drosophila compound eye

Drosophila phototransduction is a well-established model for characterizing biological processes, such as calcium signaling. Here, we present a protocol for electroretinogram (ERG) recording, an in-vivo physiological assay extensively used in Drosophila phototransduction research to measure light-evoked field potential responses of photoreceptors and neurons in the lamina neuropil. We describe fly preparation and electrode placement, followed by pretest setup, ERG recording, and data analysis. This protocol enables assessment of photoreceptor performance and visual synaptic transmission between photoreceptors and downstream lamina neurons.

For complete details on the use and execution of this protocol, please refer to Han et al. (2006), Hu et al. (2012), and Wu et al. (2021).

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Optimized protocol to detect the rapid response upon light stimulation of Drosophila

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Protocol facilitates large-scale genetic screening of Drosophila

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Detailed procedures for ERG recordings under normal and restrictive conditions

Drosophila sensory receptors-a set of molecular Swiss Army Knives

Genetic approaches in the fruit fly, Drosophila melanogaster, have led to a major triumph in the field of sensory biology-the discovery of multiple large families of sensory receptors and channels. Some of these families, such as transient receptor potential channels, are conserved from animals ranging from worms to humans, while others, such as "gustatory receptors," "olfactory receptors," and "ionotropic receptors," are restricted to invertebrates. Prior to the identification of sensory receptors in flies, it was widely assumed that these proteins function in just one modality such as vision, smell, taste, hearing, and somatosensation, which includes thermosensation, light, and noxious mechanical touch. By employing a vast combination of genetic, behavioral, electrophysiological, and other approaches in flies, a major concept to emerge is that many sensory receptors are multitaskers. The earliest example of this idea was the discovery that individual transient receptor potential channels function in multiple senses. It is now clear that multitasking is exhibited by other large receptor families including gustatory receptors, ionotropic receptors, epithelial Na+ channels (also referred to as Pickpockets), and even opsins, which were formerly thought to function exclusively as light sensors. Genetic characterizations of these Drosophila receptors and the neurons that express them also reveal the mechanisms through which flies can accurately differentiate between different stimuli even when they activate the same receptor, as well as mechanisms of adaptation, amplification, and sensory integration. The insights gleaned from studies in flies have been highly influential in directing investigations in many other animal models.