@article{ReinhardBertoliniSaitoetal.2022,
  author    = {Reinhard, Nils and Bertolini, Enrico and Saito, Aika and Sekiguchi, Manabu and Yoshii, Taishi and Rieger, Dirk and Helfrich-F{\"o}rster, Charlotte},
  title     = {The lateral posterior clock neurons of Drosophila melanogaster express three neuropeptides and have multiple connections within the circadian clock network and beyond},
  series = {Journal of Comparative Neurology},
  volume    = {530},
  journal   = {Journal of Comparative Neurology},
  number    = {9},
  doi       = {10.1002/cne.25294},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-276456},
  pages     = {1507 -- 1529},
  year      = {2022},
  abstract  = {Drosophila's lateral posterior neurons (LPNs) belong to a small group of circadian clock neurons that is so far not characterized in detail. Thanks to a new highly specific split-Gal4 line, here we describe LPNs' morphology in fine detail, their synaptic connections, daily bimodal expression of neuropeptides, and propose a putative role of this cluster in controlling daily activity and sleep patterns. We found that the three LPNs are heterogeneous. Two of the neurons with similar morphology arborize in the superior medial and lateral protocerebrum and most likely promote sleep. One unique, possibly wakefulness-promoting, neuron with wider arborizations extends from the superior lateral protocerebrum toward the anterior optic tubercle. Both LPN types exhibit manifold connections with the other circadian clock neurons, especially with those that control the flies' morning and evening activity (M- and E-neurons, respectively). In addition, they form synaptic connections with neurons of the mushroom bodies, the fan-shaped body, and with many additional still unidentified neurons. We found that both LPN types rhythmically express three neuropeptides, Allostatin A, Allostatin C, and Diuretic Hormone 31 with maxima in the morning and the evening. The three LPN neuropeptides may, furthermore, signal to the insect hormonal center in the pars intercerebralis and contribute to rhythmic modulation of metabolism, feeding, and reproduction. We discuss our findings in the light of anatomical details gained by the recently published hemibrain of a single female fly on the electron microscopic level and of previous functional studies concerning the LPN.},
  language  = {en}
}
@article{ChenReiherHermannLuibletal.2016,
  author    = {Chen, Jiangtian and Reiher, Wencke and Hermann-Luibl, Christiane and Sellami, Azza and Cognigni, Paola and Kondo, Shu and Helfrich-F{\"o}rster, Charlotte and Veenstra, Jan A. and Wegener, Christian},
  title     = {Allatostatin A Signalling in Drosophila Regulates Feeding and Sleep and Is Modulated by PDF},
  series = {PLoS Genetics},
  volume    = {12},
  journal   = {PLoS Genetics},
  number    = {9},
  doi       = {10.1371/journal.pgen.1006346},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-178170},
  year      = {2016},
  abstract  = {Feeding and sleep are fundamental behaviours with significant interconnections and cross-modulations. The circadian system and peptidergic signals are important components of this modulation, but still little is known about the mechanisms and networks by which they interact to regulate feeding and sleep. We show that specific thermogenetic activation of peptidergic Allatostatin A (AstA)-expressing PLP neurons and enteroendocrine cells reduces feeding and promotes sleep in the fruit fly Drosophila. The effects of AstA cell activation are mediated by AstA peptides with receptors homolog to galanin receptors subserving similar and apparently conserved functions in vertebrates. We further identify the PLP neurons as a downstream target of the neuropeptide pigment-dispersing factor (PDF), an output factor of the circadian clock. PLP neurons are contacted by PDF-expressing clock neurons, and express a functional PDF receptor demonstrated by cAMP imaging. Silencing of AstA signalling and continuous input to AstA cells by tethered PDF changes the sleep/activity ratio in opposite directions but does not affect rhythmicity. Taken together, our results suggest that pleiotropic AstA signalling by a distinct neuronal and enteroendocrine AstA cell subset adapts the fly to a digestive energy-saving state which can be modulated by PDF.},
  language  = {en}
}