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Updated: Jul 17, 2026
07:13
3D Modeling of Dendritic Spines with Synaptic Plasticity
Published on: May 18, 2020
The postsynaptic architecture of excitatory synapses: a more quantitative view
Morgan Sheng1, Casper C Hoogenraad
1The Picower Institute for Learning and Memory, Howard Hughes Medical Institute, Departments of Brain and Cognitive Sciences, and Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA. msheng@mit.edu
Annual Review of Biochemistry
|January 25, 2007
Summary
The postsynaptic density (PSD) is a complex protein structure at excitatory synapses in the brain. Recent studies reveal its molecular organization and dynamic architecture, offering a more precise understanding of brain function.
Area of Science:
- Neuroscience
- Molecular Biology
- Cell Biology
Background:
- Excitatory synapses in the mammalian brain are located on dendritic spines.
- Dendritic spines contain organelles for protein synthesis, membrane trafficking, and calcium metabolism.
- The postsynaptic membrane is rich in glutamate receptors, signaling proteins, and cytoskeletal elements organized into the postsynaptic density (PSD).
Purpose of the Study:
- To investigate the molecular organization and architecture of the postsynaptic density (PSD).
- To understand the dynamic changes in PSD structure and composition during development and in response to synaptic activity.
Main Methods:
- Recent measurements of the molecular size and stoichiometry of major PSD constituents.
- Low-resolution electron microscopy studies to determine the structure of PSD proteins and their spatial arrangement.
Main Results:
- The PSD is a complex assembly of hundreds of distinct proteins.
- PSD structure and composition are dynamic, changing with development and synaptic activity.
- Quantitative data on PSD molecular size, stoichiometry, and protein arrangement are emerging.
Conclusions:
- A more quantitative and geometrically realistic model of PSD architecture is being developed.
- Understanding PSD structure is crucial for comprehending excitatory synaptic function and plasticity.
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