Neuromodulation of excitatory synaptogenesis in striatal development

Area of Science:

• Neuroscience
• Developmental Biology
• Cellular Signaling

Background:

• Dopamine release in the developing striatum modulates Protein Kinase A (PKA) activity in spiny projection neurons (SPNs).
• Understanding dopaminergic influence on synapse formation is crucial for deciphering developmental plasticity in the striatum.

Purpose of the Study:

• To investigate how dopaminergic neuromodulation regulates activity-dependent glutamatergic synapse formation in the developing striatum.
• To elucidate the roles of Gαs-coupled GPCRs and PKA in synaptic development within direct (dSPNs) and indirect (iSPNs) pathway neurons.

Main Methods:

• Systemic in vivo administration of Gαs-coupled GPCR agonists.
• In vitro experiments involving glutamate photolysis and Gαs activation.
• Evaluation of enhanced glutamate release from corticostriatal axons and postsynaptic PKA activity in vivo.

Main Results:

• Gαs-coupled GPCR agonists enhanced excitatory synapses on dSPNs in vivo.
• Rapid excitatory synapse formation on iSPNs required Gαs GPCR activation in both dSPNs and iSPNs.
• In vitro Gαs activation enhanced spinogenesis in both dSPNs and iSPNs, indicating additional requirements for iSPNs in intact circuits.

Conclusions:

• Rapid synaptogenesis in the developing striatum is promoted by the coordinated action of glutamate and postsynaptic Gαs-coupled receptors.
• This mechanism highlights a novel form of developmental plasticity involving dopaminergic modulation of synaptic development.