Abstract
Altering AMPA receptor (AMPAR) content at synapses is a key mechanism underlying the regulation of synaptic strength during learning and memory. Previous work demonstrated that SynDIG1 (synapse differentiation-induced gene 1) encodes a transmembrane AMPAR-associated protein that regulates excitatory synapse strength and number. Here we show that the related protein SynDIG4 (also known as Prrt1) modifies AMPAR gating properties in a subunit-dependent manner. Young SynDIG4 knockout (KO) mice have weaker excitatory synapses, as evaluated by immunocytochemistry and electrophysiology. Adult SynDIG4 KO mice show complete loss of tetanus-induced long-term potentiation (LTP), while mEPSC amplitude is reduced by only 25%. Furthermore, SynDIG4 KO mice exhibit deficits in two independent cognitive assays. Given that SynDIG4 colocalizes with the AMPAR subunit GluA1 at non-synaptic sites, we propose that SynDIG4 maintains a pool of extrasynaptic AMPARs necessary for synapse development and function underlying higher-order cognitive plasticity. Matt et al. show that mice lacking the AMPAR-associated protein SynDIG4/Prrt1 display deficits in synaptic plasticity and cognition. SynDIG4 modifies AMPAR biophysical properties in heterologous cells, but synaptic AMPAR kinetics are unchanged, suggesting that SynDIG4 establishes a pool of extrasynaptic AMPARs necessary for higher-order cognitive plasticity.
Original language | English |
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Pages (from-to) | 2246-2253 |
Number of pages | 8 |
Journal | Cell Reports |
Volume | 22 |
Issue number | 9 |
DOIs | |
State | Published - 27 Feb 2018 |
Bibliographical note
Funding Information:Funding was provided by the American Heart Association ( 11POST7020009 to L.M.), Brain & Behavior Research Foundation NARSAD Young Investigator (grant 20748 to L.M.), United States-Israel Binational Science Foundation (BSF; grant 2012781 to Y.S.-B.) and the United States National Science Foundation (NSF; grant 1322302 to E.D.), NIH ( R01 MH097887 to J.W.H., R01 NS078792 to J.W.H., U54 HD079125 MCP to J.L.S. and J.N.C.) and NIH New Director’s Innovator Award Program ( DP2 OD006479-01 to E.D.), UC Davis Academic Senate Research Program Pilot Grant (to E.D.), and Whitehall Foundation ( 2015-05-106 to E.D.). L.M.K. is a trainee of the UC Davis MCB T32 Training Program (award GM007377 ). SynDIG4 KO mice were generated using the UC Davis Mouse Biology Program.
Funding Information:
Funding was provided by the American Heart Association (11POST7020009 to L.M.), Brain & Behavior Research Foundation NARSAD Young Investigator (grant 20748 to L.M.), United States-Israel Binational Science Foundation (BSF; grant 2012781 to Y.S.-B.) and the United States National Science Foundation (NSF; grant 1322302 to E.D.), NIH (R01 MH097887 to J.W.H., R01 NS078792 to J.W.H., U54 HD079125 MCP to J.L.S. and J.N.C.) and NIH New Director's Innovator Award Program (DP2 OD006479-01 to E.D.), UC Davis Academic Senate Research Program Pilot Grant (to E.D.), and Whitehall Foundation (2015-05-106 to E.D.). L.M.K. is a trainee of the UC Davis MCB T32 Training Program (award GM007377). SynDIG4 KO mice were generated using the UC Davis Mouse Biology Program.
Publisher Copyright:
© 2018 The Authors
Keywords
- LTP
- NG5
- Prrt1
- SynDIG family
- SynDIG4
- auxiliary factor
- excitatory synapse
- extrasynaptic AMPARs
- hippocampus