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Improved Preparation and Preservation of Hippocampal Mouse Slices for a Very Stable and Reproducible Recording of Long-term Potentiation
Published on: June 26, 2013
The MUPP1-SynGAPalpha protein complex does not mediate activity-induced LTP
Sylvain Rama1, Grigory Krapivinsky, David E Clapham
1INMED/INSERM Unite 901, 163 Route de Luminy, 13009 Marseille, France; Mediterranean University, 163 Route de Luminy, 13009 Marseille, France.
Molecular and Cellular Neurosciences
|April 18, 2008
Summary
Disrupting the MUPP1-SynGAP complex in hippocampal neurons enhances excitatory postsynaptic currents (EPSCs). This MUPP1-SynGAP interaction disruption reveals a novel mechanism for AMPA receptor (AMPAR) potentiation, separate from long-term potentiation (LTP).
Area of Science:
- Neuroscience
- Molecular Biology
- Synaptic Plasticity
Background:
- MUPP1 is a scaffolding protein at excitatory synapses.
- MUPP1 organizes NMDA receptor subunit NR2B, Ca2+-calmodulin kinase (CamKII), and SynGAPalpha.
Purpose of the Study:
- To investigate the role of the MUPP1-SynGAPalpha complex in excitatory synaptic neurotransmission.
- To determine if disrupting this complex affects synaptic function.
Main Methods:
- Used acute hippocampal slices from CA1 neurons.
- Disrupted MUPP1-SynGAPalpha interactions via intracellular perfusion with specific peptides.
- Measured excitatory postsynaptic currents (EPSCs).
Main Results:
- Disrupting MUPP1-SynGAPalpha interactions enhanced EPSCs.
- This enhancement did not interfere with long-term potentiation (LTP).
- Activity-induced potentiation further increased postsynaptic response amplitude.
Conclusions:
- MUPP1-SynGAPalpha complex dissociation triggers AMPA receptor (AMPAR) enhancement.
- This mechanism is distinct from activity-induced LTP.
- Suggests a novel pathway for synaptic potentiation.
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