title: Engrams and circuits crucial for systems consolidation of a memory.
abstract: Episodic memories initially require rapid synaptic plasticity within the hippocampus for their formation and are gradually consolidated in neocortical networks for permanent storage. However, the engrams and circuits that support neocortical memory consolidation have thus far been unknown. We found that neocortical prefrontal memory engram cells, which are critical for remote contextual fear memory, were rapidly generated during initial learning through inputs from both the hippocampal-entorhinal cortex network and the basolateral amygdala. After their generation, the prefrontal engram cells, with support from hippocampal memory engram cells, became functionally mature with time. Whereas hippocampal engram cells gradually became silent with time, engram cells in the basolateral amygdala, which were necessary for fear memory, were maintained. Our data provide new insights into the functional reorganization of engrams and circuits underlying systems consolidation of memory.
authors.affiliation: RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Departments of Biology and Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Takashi
authors.identifier: 0000-0001-5597-859X
authors.initials: T
authors.lastname: Kitamura
authors.affiliation: RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Departments of Biology and Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Sachie K
authors.identifier: 0000-0003-1982-634X
authors.initials: SK
authors.lastname: Ogawa
authors.affiliation: RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Departments of Biology and Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Dheeraj S
authors.identifier: 0000-0002-5218-1216
authors.initials: DS
authors.lastname: Roy
authors.affiliation: RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Departments of Biology and Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Teruhiro
authors.initials: T
authors.lastname: Okuyama
authors.affiliation: RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Departments of Biology and Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Mark D
authors.identifier: 0000-0002-3300-162X
authors.initials: MD
authors.lastname: Morrissey
authors.affiliation: RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Departments of Biology and Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Lillian M
authors.initials: LM
authors.lastname: Smith
authors.affiliation: RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Departments of Biology and Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.|Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Roger L
authors.identifier: 0000-0002-3477-689X
authors.initials: RL
authors.lastname: Redondo
authors.affiliation: RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Departments of Biology and Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. tonegawa@mit.edu.|Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Susumu
authors.identifier: 0000-0003-2839-8228
authors.initials: S
authors.lastname: Tonegawa
mesh_terms: D000679:Amygdala / Q000502:physiology; D000818:Animals; D003213:Conditioning, Psychological; D018728:Entorhinal Cortex / Q000502:physiology*; D005239:Fear / Q000502:physiology; D006624:Hippocampus / Q000502:physiology*; D008297:Male; D000069077:Memory Consolidation / Q000502:physiology*; D061212:Memory, Episodic; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009434:Neural Pathways / Q000502:physiology; D009473:Neuronal Plasticity; D017397:Prefrontal Cortex / Q000166:cytology / Q000502:physiology*