title: Specific requirement of NMDA receptors for long-term memory consolidation in Drosophila ellipsoid body.
abstract: In humans and many other animals, memory consolidation occurs through multiple temporal phases and usually involves more than one neuroanatomical brain system. Genetic dissection of Pavlovian olfactory learning in Drosophila melanogaster has revealed multiple memory phases, but the predominant view holds that all memory phases occur in mushroom body neurons. Here, we demonstrate an acute requirement for NMDA receptors (NMDARs) outside of the mushroom body during long-term memory (LTM) consolidation. Targeted dsRNA-mediated silencing of Nmdar1 and Nmdar2 (also known as dNR1 or dNR2, respectively) in cholinergic R4m-subtype large-field neurons of the ellipsoid body specifically disrupted LTM consolidation, but not retrieval. Similar silencing of functional NMDARs in the mushroom body disrupted an earlier memory phase, leaving LTM intact. Our results clearly establish an anatomical site outside of the mushroom body involved with LTM consolidation, thus revealing both a distributed brain system subserving olfactory memory formation and the existence of a system-level memory consolidation in Drosophila.
authors.affiliation: Institute of Biotechnology and Department of Life Science, National Tsing Hua University, 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan.
authors.forename: Chia-Lin
authors.initials: CL
authors.lastname: Wu
authors.forename: Shouzhen
authors.initials: S
authors.lastname: Xia
authors.forename: Tsai-Feng
authors.initials: TF
authors.lastname: Fu
authors.forename: Huaien
authors.initials: H
authors.lastname: Wang
authors.forename: Ying-Hsiu
authors.initials: YH
authors.lastname: Chen
authors.forename: Daniel
authors.initials: D
authors.lastname: Leong
authors.forename: Ann-Shyn
authors.initials: AS
authors.lastname: Chiang
authors.forename: Tim
authors.initials: T
authors.lastname: Tully
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D030801:Animals, Genetically Modified; D001245:Association Learning / Q000187:drug effects / Q000502:physiology*; D001522:Behavior, Animal; D001921:Brain / Q000166:cytology*; D003214:Conditioning, Classical; D004330:Drosophila; D029721:Drosophila Proteins / Q000235:genetics; D018782:Maze Learning; D008568:Memory / Q000187:drug effects / Q000502:physiology*; D024521:Mushroom Bodies / Q000187:drug effects / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D009812:Odorants; D012330:RNA, Double-Stranded / Q000494:pharmacology; D016194:Receptors, N-Methyl-D-Aspartate / Q000235:genetics / Q000502:physiology*; D013997:Time Factors
chemical_list: D029721:Drosophila Proteins; C409466:NR1 NMDA receptor; C120997:NR2A NMDA receptor; D012330:RNA, Double-Stranded; D016194:Receptors, N-Methyl-D-Aspartate