ACTIVITY INDUCED CHANGES IN THE DISTRIBUTION OF SHANKS AT HIPPOCAMPAL SYNAPSES

作者：Tao Cheng J H^*; Dosemeci A; Gallant P E; Smith C; Reese T

来源：Neuroscience, 2010, 168(1): 11-17.

DOI：10.1016/j.neuroscience.2010.03.041

• postsynaptic density
• electron microscopy
• Shank1
• Shank2

Dendritic spines contain a family of abundant scaffolding proteins known as Shanks, but little is known about how their distributions might change during synaptic activity. Here, pre-embedding immunogold electron microscopy is used to localize Shanks in synapses from cultured hippocampal neurons. We find that Shanks are preferentially located at postsynaptic densities (PSDs) as well as in a filamentous network near the PSD, extending up to 120 nm from the postsynaptic membrane. Application of sub-type specific antibodies shows that Shank2 is typically concentrated at and near PSDs while Shank1 is, in addition, distributed throughout the spine head. Depolarization with high K(+) for 2 min causes transient, reversible translocation of Shanks towards the PSD that is dependent on extracellular Ca(2+). The amount of activity-induced redistribution and subsequent recovery is pronounced for Shank1 but less so for Shank2. Thus, Shank1 appears to be a dynamic element within the spine, whose translocation could be involved in activity-induced, transient structural changes, while Shank2 appears to be a more stable element positioned at the interface of the PSD with the spine cytoplasm. Published by Elsevier Ltd on behalf of IBRO.

• 出版日期2010-6-16