title: Retrograde BMP signaling controls Drosophila behavior through regulation of a peptide hormone battery.
abstract: Retrograde BMP signaling in neurons plays conserved roles in synaptic efficacy and subtype-specific gene expression. However, a role for retrograde BMP signaling in the behavioral output of neuronal networks has not been established. Insect development proceeds through a series of stages punctuated by ecdysis, a complex patterned behavior coordinated by a dedicated neuronal network. In Drosophila, larval ecdysis sheds the old cuticle between larval stages, and pupal ecdysis everts the head and appendages to their adult external position during metamorphosis. Here, we found that mutants of the type II BMP receptor wit exhibited a defect in the timing of larval ecdysis and in the completion of pupal ecdysis. These phenotypes largely recapitulate those previously observed upon ablation of CCAP neurons, an integral subset of the ecdysis neuronal network. Here, we establish that retrograde BMP signaling in only the efferent subset of CCAP neurons (CCAP-ENs) is required to cell-autonomously upregulate expression of the peptide hormones CCAP, Mip and Bursicon β. In wit mutants, restoration of wit exclusively in CCAP neurons significantly rescued peptide hormone expression and ecdysis phenotypes. Moreover, combinatorial restoration of peptide hormone expression in CCAP neurons in wit mutants also significantly rescued wit ecdysis phenotypes. Collectively, our data demonstrate a novel role for retrograde BMP signaling in maintaining the behavioral output of a neuronal network and uncover the underlying cellular and gene regulatory substrates.
authors.affiliation: Department of Cellular and Physiological Sciences, Room 2420 Life Sciences Centre, 2350 Health Sciences Mall, University of British Columbia, Vancouver, BC V6T 1Z3, Canada.
authors.forename: Lyubov
authors.initials: L
authors.lastname: Veverytsa
authors.forename: Douglas W
authors.initials: DW
authors.lastname: Allan
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D019485:Bone Morphogenetic Proteins / Q000235:genetics / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism; D004331:Drosophila melanogaster / Q000033:anatomy & histology / Q000196:embryology / Q000254:growth & development / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental; D007301:Insect Hormones / Q000235:genetics / Q000378:metabolism*; D007814:Larva / Q000502:physiology; D018978:Molting / Q000502:physiology; D009474:Neurons / Q000166:cytology / Q000502:physiology; D036361:Peptide Hormones / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype; D011679:Pupa / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology*
chemical_list: D019485:Bone Morphogenetic Proteins; D029721:Drosophila Proteins; D007301:Insect Hormones; D036361:Peptide Hormones