2023
bioRxiv

Neuronal activity modulates the incorporation of newly translated PSD-95 into a robust structure as revealed by STED and MINFLUX

Authors:

Clara-Marie Gürth, Maria Augusta do Rego Barros Fernandes Lima, Victor Macarrón Palacios, Jasmine Hubrich, Angel Rafael Cereceda Delgado,Nikolaos Mougios, Felipe Opazo, Elisa D’Este

Keywords:

PSD-95; synapse; synaptic plasticity

Abstract:

The postsynaptic density component PSD-95 undergoes activity-dependent plasticity mechanisms that rely on protein synthesis and structural remodeling. How synaptic activity can influence these dynamics at the single synapse level remains unclear. Here we combine genome-editing, pulse-chase experiments, STED and 3D MINFLUX nanoscopy on hippocampal neuronal cultures to study the integration of newly translated PSD-95 molecules at postsynaptic sites and their rearrangement within individual clusters at near-molecular resolution. We show that the amount of newly translated PSD-95 recruited to individual synapses scales with synaptic size, and modulates in a bidirectional manner, resulting in less new protein following excitatory and more new protein following inhibitory stimulation. Furthermore, we show that within synaptic clusters PSD-95 has a dispersed organization that is largely robust to long-lasting changes in activity. Altogether, this work sheds new light on the mechanisms underlying plasticity at the single synapse level, adding previously inaccessible information.