Neuropeptides in modulation of Drosophila behavior: how to get a grip on their pleiotropic actions

Abstract

Neuropeptides constitute a large and diverse class of signaling molecules that are produced by many types of neurons, neurosecretory cells, endocrines and other cells. Many neuropeptides display pleiotropic actions either as neuromodulators, co-transmitters or circulating hormones, while some play these roles concurrently. Here, we highlight pleiotropic functions of neuropeptides and different levels of neuropeptide signaling in the brain, from context-dependent orchestrating signaling by higher order neurons, to local executive modulation in specific circuits. Additionally, orchestrating neurons receive peptidergic signals from neurons conveying organismal internal state cues and relay these to executive circuits. We exemplify these levels of signaling with four neuropeptides, SIFamide, short neuropeptide F, allatostatin-A and leucokinin, each with a specific expression pattern and level of complexity in signaling.

Neuropeptide relay between SIFa signaling controls the experience-dependent mating duration of male Drosophila

“…Neuropeptides constitutes a large and diverse class of signaling molecules that are produced by various types of neurons, which modulates many insect behaviours and physiology [3,4]. Recent advances in neurobiological research have suggested that neural circuits encompassing neuropeptide relay signaling are essential modulators for various behaviours, including feeding, energy homeostasis, sleep and wakefulness [5][6][7][8][9][10][11].…”

Ancient role of sulfakinin/cholecystokinin-type signalling in inhibitory regulation of feeding processes revealed in an echinoderm

“…The effects of ArSK/CCK1 and ArSK/CCK2 in triggering cardiac stomach retraction in A. rubens (see above) suggested that SK/CCK-type signalling may have a physiological role in inhibition and/or termination of feeding behaviour in starfish, which would be consistent with the physiological roles of SK/CCK-type neuropeptides in other taxa ( Al-Alkawi et al, 2017 ; Downer et al, 2007 ; Kang et al, 2011 ; Maestro et al, 2001 ; Meyering-Vos and Müller, 2007 ; Nachman et al, 1986b ; Nässel et al, 2019 ; Rehfeld, 2017 ; Roman et al, 2017 ; Wei, 2000 ; Yu et al, 2013a ; Zels et al, 2015 ; Zhang et al, 2017 ). Therefore, we performed experiments to specifically investigate if ArSK/CCK1 and ArSK/CCK2 have inhibitory effects on starfish feeding behaviour on prey (mussels).…”

Heterogeneous Receptor Expression Underlies Non-uniform Peptidergic Modulation of Olfaction inDrosophila

“… Sensory systems are dynamically adjusted according to the animal’s ongoing needs by neuromodulators, such as neuropeptides. Despite their prevalence across all nervous systems 1,2 , how peptidergic neurons and the neuropeptide they release act to adjust sensory processing remains poorly understood. Here, we reveal that a heterogeneous ensemble of local interneurons (LNs) release the neuropeptide myoinhibitory peptide (MIP) within the Drosophila primary olfactory center (the antennal lobe, AL).…”