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bioRxiv · 10.1101/2020.04.14.041038

Syngap1 Dynamically Regulates the Fine-Scale Reorganization of Cortical Circuits in Response to Sensory Experience

Llamosas, N.·Vaissiere, T.·Rojas, C.·Michaelson, S. D.·Miller, C. A.·Rumbaugh, G.
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Abstract

Experience induces complex, neuron-specific changes in population activity within sensory cortex circuits. However, the mechanisms that enable neuron-specific changes within cortical populations remain unclear. To explore the idea that synapse strengthening is involved, we studied fine-scale cortical plasticity in Syngap1 mice, a neurodevelopmental disorder model useful for linking synapse biology to circuit functions. Repeated functional imaging of the same L2/3 somatosensory cortex neurons during single whisker experience revealed that Syngap1 selectively regulated the plasticity of a low-active, or "silent", neuronal subpopulation. Syngap1 also regulated spike-timing-dependent synaptic potentiation and experience-mediated in vivo synapse bouton formation, but not synaptic depression or bouton elimination in L2/3. Adult re-expression of Syngap1 restored plasticity of "silent" neurons, demonstrating that this gene controls dynamic cellular processes required for population-specific changes to cortical circuits during experience. These findings suggest that abnormal experience-dependent redistribution of cortical population activity may contribute to the etiology of neurodevelopmental disorders.

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Llamosas, N., Vaissiere, T., Rojas, C., Michaelson, S. D., Miller, C. A., Rumbaugh, G.. 2020-04-15. Syngap1 Dynamically Regulates the Fine-Scale Reorganization of Cortical Circuits in Response to Sensory Experience. https://doi.org/10.1101/2020.04.14.041038

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