Dopamine modulates the optomotor response to unreliable visual stimuli in Drosophila melanogaster. (30th December 2019)

• Record Type: Journal Article
• Authors: Akiba, Masumi; Sugimoto, Kentaro; Aoki, Risa; Murakami, Ryo; Miyashita, Tomoyuki; Hashimoto, Riho; Hiranuma, Anna; Yamauchi, Junji; Ueno, Taro; Morimoto, Takako
• Is Part Of: European journal of neuroscience. Volume 51:Number 3(2020)
• Page Start: 822
• Page End: 839
• Publication Date: 2019-12-30
• Subjects: central complex -- dopamine receptor -- fan‐shaped body -- noise -- pontine neurons; Nervous system -- Periodicals; 612.8
• DOI: 10.1111/ejn.14648
• Languages: English
• ISSNs: 0953-816X

Abstract

Abstract: State‐dependent modulation of sensory systems has been studied in many organisms and is possibly mediated through neuromodulators such as monoamine neurotransmitters. Among these, dopamine is involved in many aspects of animal behaviour, including movement control, attention, motivation and cognition. However, the precise neural mechanism underlying dopaminergic modulation of behaviour induced by sensory stimuli remains poorly understood. Here, we used Drosophila melanogaster to show that dopamine can modulate the optomotor response to moving visual stimuli including noise. The optomotor response is the head‐turning response to moving objects, which is observed in most sight‐reliant animals including mammals and insects. First, the effects of the dopamine system on the optomotor response were investigated in mutant flies deficient in dopamine receptors D1R1 or D1R2, which are involved in the modulation of sleep‐arousal in flies. We examined the optomotor response in D1R1 knockout (D1R1 KO) and D1R2 knockout (D1R2 KO) flies and found that it was not affected in D1R1 KO flies; however, it was significantly reduced in D1R2 KO flies compared with the wild type. Using cell‐type‐specific expression of an RNA interference construct of D1R2, we identified the fan‐shaped body, a part of the central complex, responsible for dopamine‐mediated modulation of the optomotor response. In particular, pontine cells in the fan‐shaped body seemed important in the modulation of the optomotor response, and their neural activity was required for the optomotor response. These results suggest a novel role of the central complex in the modulation of a behaviour based on the processing of sensory stimulations. Abstract : We show that dopamine modulates the optomotor response (OMR) to moving visual stimuli in Drosophila melanogaster . It is likely that the D1‐like dopamine receptor D1R2, expressed in pontine neurons of the fan‐shaped body, a part of central complex, mediates OMR modulation. This OMR modulation is prominent when flies respond to unreliable stimuli such as vertical stripes that contain noise. The importance of neural activity in this brain region will be discussed.