※ Postsynaptic density introduction

    Postsynaptic densities (PSDs) are membrane semienclosed, submicron protein-enriched cellular compartments beneath postsynaptic membranes, which constantly exchange their components with bulk aqueous cytoplasm in synaptic spines, it is an assembly responsible for receiving, interpreting, and storage of signals transmitted by presynaptic axonal termini. Both molecular components and motions of each component within PSDs are highly dynamic, formation and activity dependent modulation of PSDs is considered as one of the most basic molecular events governing synaptic plasticity in the nervous system (1).

Reference
1. Zeng, M., Shang, Y., Araki, Y., Guo, T., Huganir, RL., Zhang, M. (2016) Phase Transition in Postsynaptic Densities Underlies Formation of Synaptic Complexes and Synaptic Plasticity. Cell, 166(5):1163-1175. PMID: 27565345