Identification and In Vivo Characterisation of Cardioactive Peptides in Drosophila melanogaster

Abstract

Neuropeptides and peptide hormones serve as critical regulators of numerous biological processes, including development, growth, reproduction, physiology, and behaviour. In mammals, peptidergic regulatory systems are complex and often involve multiple peptides that act at different levels and relay to different receptors. To improve the mechanistic understanding of such complex systems, invertebrate models in which evolutionarily conserved peptides and receptors regulate similar biological processes but in a less complex manner have emerged as highly valuable. Drosophila melanogaster represents a favoured model for the characterisation of novel peptidergic signalling events and for evaluating the relevance of those events in vivo. In the present study, we analysed a set of neuropeptides and peptide hormones for their ability to modulate cardiac function in semi-intact larval Drosophila melanogaster. We identified numerous peptides that significantly affected heart parameters such as heart rate, systolic and diastolic interval, rhythmicity, and contractility. Thus, peptidergic regulation of the Drosophila heart is not restricted to chronotropic adaptation but also includes inotropic modulation. By specifically interfering with the expression of corresponding peptides in transgenic animals, we assessed the in vivo relevance of the respective peptidergic regulation. Based on the functional conservation of certain peptides throughout the animal kingdom, the identified cardiomodulatory activities may be relevant not only to proper heart function in Drosophila, but also to corresponding processes in vertebrates, including humans.

Nitric oxide produced by periostial hemocytes modulates the bacterial infection induced reduction of the mosquito heart rate

“…Lysozyme mRNA has been detected in the heart of another anopheline species (Hernández-Martínez et al, 2013). However, higher resolution histochemical studies on moths and flies uncovered that pericardial cells, and not the cardiac muscle, contain lysozyme (Crossley, 1972;Russell and Dunn, 1990). When considered together with our transcriptional data, we predict that lysozymes are produced by pericardical cells and additional cells that had not been discovered when the histochemical experiments were conducted: periostial hemocytes.…”

Allatostatin A Signalling: Progress and New Challenges From a Paradigmatic Pleiotropic Invertebrate Neuropeptide Family

“…A recent screen for cardioactive peptides in the Drosophila larva revealed a role of AstA in modulating heart rate and rhythmicity (Schiemann et al, 2019). When applied to a semi-intact larval preparation, AstA had a mild to strong chronotropic effect and at 10 −7 M led to heartbeat arrest.…”

A neural signature of choice under sensory conflict inDrosophila

“…During foraging, animals compute value estimates of internal hunger state and external sensory environment such valence of available foods, location of food, etc. Various neuromodulators regulate hunger dependent food intake [6][7][8][9][10][11][12] , reward [13][14][15][16] or punishment 17 , as well as memory 14,16,18 . The mushroom body is an insect central brain region involved in gustatory learning and memory 19,20 and valence encoding 21 , and is thought to be a major center controlling higher-order behaviors [22][23][24] .…”

“…2, UAS-Lkr-RNAi 11,13,15 RRID:BDSC_25936 Fig. 2, UAS-AstA-RNAi 14,16 RRID:BDSC_25866 Fig. 2, UAS-AstA-R1-RNAi 17 RRID:BDSC_27280 Fig.…”