title: Daphnia longicephala neuropeptides: morphological description of crustacean cardioactive peptide (CCAP) and periviscerokinins in the Ctenodaphnia central nervous system.
abstract: The publication of the Daphnia genome has driven research in this ecologically relevant model organism in many directions. However, information on this organism's physiology and the relevant controlling factors is limited. In this regard, especially neuropeptides are important biochemical regulators that control a variety of cellular processes, which in combination influence physiological conditions and allow the adaptation of the internal physiological state to external conditions. Thus, neuropeptides are prime in understanding an organism's physiology. We here aimed to detect and describe the distribution of evolutionary conserved neuropeptides including the crustacean cardioactive peptide (CCAP) and peptides of the family periviscerokinins (PVKs) in the central nervous system and the periphery of the Daphnia longicephala head region. We were able to identify a large pair of CCAP immunoreactive cells within central nervous system. In addition, in the periphery we found CCAP immunoreactive cells in the epidermis of the head with processes indicating cuticular secretion. Furthermore, we were able to identify and describe a complex neuronal circuit of PVK neuropeptides in the central nervous system. The data obtained in this study will provide important background information for future investigations aiming to unravel the cellular, neuronal and physiological pathways in a highly adaptive organism such as Daphnia.
authors: Dept. Animal Ecology, Evolution and Biodiversity, Ruhr University Bochum, Universitätsstr. 150, 447801 Bochum, Germany. Electronic address: linda.weiss@rub.de.
authors: Linda C
authors: LC
authors: Weiss
authors: Department of Animal Ecology I and BayCEER, University of Bayreuth, Universitätsstr. 30, 95440 Bayreuth, Germany.
authors: Christian
authors: C
authors: Laforsch
authors: Dept. Animal Ecology, Evolution and Biodiversity, Ruhr University Bochum, Universitätsstr. 150, 447801 Bochum, Germany.
authors: Ioanna
authors: I
authors: Ioannidou
authors: Department of Biology II, Ludwig-Maximilians-University Munich, Grosshaderner Str. 2, 82152 Planegg-Martinsried, Germany.
authors: Zsofia
authors: Z
authors: Herbert
authors: Dept. Animal Ecology, Evolution and Biodiversity, Ruhr University Bochum, Universitätsstr. 150, 447801 Bochum, Germany.
authors: Ralph
authors: R
authors: Tollrian
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism*; D003621:Daphnia / Q000378:metabolism*; D009479:Neuropeptides / Q000032:analysis*
chemical_list: D009479:Neuropeptides; C058620:crustacean cardioactive peptide; C093061:periviscerokinin
keywords: Crustacean cardioactive peptide; Daphnia; Immunohistochemistry; Nervous system; Periviscerokinins