Simultaneous activation of parallel sensory pathways promotes a grooming sequence in Drosophila

Abstract

A central model that describes how behavioral sequences are produced features a neural architecture that readies different movements simultaneously, and a mechanism where prioritized suppression between the movements determines their sequential performance. We previously described a model whereby suppression drives a Drosophila grooming sequence that is induced by simultaneous activation of different sensory pathways that each elicit a distinct movement (Seeds et al., 2014). Here, we confirm this model using transgenic expression to identify and optogenetically activate sensory neurons that elicit specific grooming movements. Simultaneous activation of different sensory pathways elicits a grooming sequence that resembles the naturally induced sequence. Moreover, the sequence proceeds after the sensory excitation is terminated, indicating that a persistent trace of this excitation induces the next grooming movement once the previous one is performed. This reveals a mechanism whereby parallel sensory inputs can be integrated and stored to elicit a delayed and sequential grooming response.

Distinct subpopulations of mechanosensory chordotonal organ neurons elicit grooming of the fruit fly antennae

“…After that we used a post-hoc Mann-Whitney U test and applied Bonferroni correction. The changes in grooming that we observed by activating the different JON subpopulations had a comparable effect size to our previously published work (Hampel et al, 2017(Hampel et al, , 2015. Therefore, at least 10 experimental and 10 control flies were tested (95% power to detect a 1.48 effect size at a 0.05 significance level).…”

“…The red light-gated neural activator CsChrimson (Klapoetke et al, 2014) was expressed using the different JO-C/E and -F driver lines. Flies were placed in chambers so that they could move freely and were then exposed to red light to induce optogenetic activation of the JONs (Hampel et al, 2017(Hampel et al, , 2015.…”

“…Wing flapping was scored when the wings started moving to the sides or up and down until no further movement was observed. Behavioral data was analyzed using nonparametric statistical tests as we previously reported (Hampel et al, 2017(Hampel et al, , 2015. We performed a Kruskal-Wallis (ANOVA) test to compare more than three genotypes with each other.…”

Olfactory and neuromodulatory signals reverse visual object avoidance to approach in Drosophila

“…The inducible nature of Chrimson allows for a within-subject experimental design to directly compare each fly's flight steering response in the absence ("LED Off") or presence ("LED On") of light-activated membrane depolarization. An enhancer-less Gal4 line 'Empty-Gal4' (Hampel et al, 2017) served as a genetic control, which evokes behavioral responses to the small object and elongated bar that are similar to those of wild-type flies ( Figure 3A, B), although the 685nm LED seems to slightly increase approach toward the bar ( Figure 3B'). Optogenetic depolarization of octopaminergic and tyraminergic neurons by the Tdc2-Gal4 driver (Cole et al, 2005) in the absence of odor strongly reverses the steering responses to the small object from aversion to approach, while also increasing the steering responses toward the bar ( Figure 3C Figure 3C, inset, red).…”

Morphological and Functional Evaluation of Axons and their Synapses during Axon Death in <em>Drosophila melanogaster</em>

“…When using CsChrimson as a channel, it is crucial to supply the food with all trans-retinal and a red LED spotlight to activate JO neurons 29 . Alternatively, blue light-sensitive channels and a blue LED spotlight, or the TrpA1 channel and temperature can be used for neuronal activation 29,33 . The quantification of grooming behavior has already been described 12,29 .…”