title: DNA methylation mediates neural processing after odor learning in the honeybee.
abstract: DNA methyltransferases (Dnmts) - epigenetic writers catalyzing the transfer of methyl-groups to cytosine (DNA methylation) - regulate different aspects of memory formation in many animal species. In honeybees, Dnmt activity is required to adjust the specificity of olfactory reward memories and bees' relearning capability. The physiological relevance of Dnmt-mediated DNA methylation in neural networks, however, remains unknown. Here, we investigated how Dnmt activity impacts neuroplasticity in the bees' primary olfactory center, the antennal lobe (AL) an equivalent of the vertebrate olfactory bulb. The AL is crucial for odor discrimination, an indispensable process in forming specific odor memories. Using pharmacological inhibition, we demonstrate that Dnmt activity influences neural network properties during memory formation in vivo. We show that Dnmt activity promotes fast odor pattern separation in trained bees. Furthermore, Dnmt activity during memory formation increases both the number of responding glomeruli and the response magnitude to a novel odor. These data suggest that Dnmt activity is necessary for a form of homoeostatic network control which might involve inhibitory interneurons in the AL network.
authors.affiliation: Queensland Brain Institute, The University of Queensland, Australia.|Neurobiologie, Universität Konstanz, Germany.
authors.forename: Stephanie D
authors.initials: SD
authors.lastname: Biergans
authors.affiliation: Queensland Brain Institute, The University of Queensland, Australia.|Monash Institute of Cognitive and Clinical Neuroscience, Faculty of Medicine, Nursing Health and Sciences, Monash University, Australia.
authors.forename: Charles
authors.initials: C
authors.lastname: Claudianos
authors.affiliation: Queensland Brain Institute, The University of Queensland, Australia.
authors.forename: Judith
authors.initials: J
authors.lastname: Reinhard
authors.affiliation: Neurobiologie, Universität Konstanz, Germany.
authors.forename: C Giovanni
authors.initials: CG
authors.lastname: Galizia
mesh_terms: D000818:Animals; D001516:Bees / Q000502:physiology*; D019175:DNA Methylation; D044127:Epigenesis, Genetic; D056726:Genetic Association Studies; D007858:Learning; D008568:Memory; D009812:Odorants; D009830:Olfactory Bulb / Q000502:physiology*; D012201:Reward