Spine-type-specific recruitment of newly synthesized AMPA receptors with learning.
The stabilization of long-term memories requires de novo protein synthesis. How can proteins, synthesized in the soma, act on specific synapses that participate in a given memory? We studied the dynamics of newly synthesized AMPA-type glutamate receptors (AMPARs) induced with learning using transgenic mice expressing the GluR1 subunit fused to green fluorescent protein (GFP-GluR1) under control of the c-fos promoter. We found learning-associated recruitment of newly synthesized GFP-GluR1 selectively to mushroom-type spines in adult hippocampal CA1 neurons 24 hours after fear conditioning. Our results are consistent with a "synaptic tagging" model to allow activated synapses to subsequently capture newly synthesized receptor and also demonstrate a critical functional distinction in the mushroom spines with learning.
Matsuo
Naoki
N
Department of Cell Biology and Institute for Childhood and Neglected Diseases, Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA. n-matsuo@fujita-hu.ac.jp
Reijmers
Leon
L
Mayford
Mark
M
D000818:Animals; D003213:Conditioning, Psychological; D049229:Dendritic Spines / Q000378:metabolism* / Q000648:ultrastructure; D004318:Doxycycline / Q000494:pharmacology; D005108:Extinction, Psychological; D005239:Fear; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism*; D007858:Learning / Q000502:physiology*; D017774:Long-Term Potentiation; D008297:Male; D008568:Memory; D051379:Mice; D008822:Mice, Transgenic; D021381:Protein Transport; D017966:Pyramidal Cells / Q000378:metabolism* / Q000648:ultrastructure; D018091:Receptors, AMPA / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000378:metabolism; D013569:Synapses / Q000378:metabolism*
D004318:Doxycycline; D018091:Receptors, AMPA; D011993:Recombinant Fusion Proteins