UMMS Affiliation

Department of Cell Biology

Date

8-17-2011

Document Type

Article

Medical Subject Headings

Animals; Cyclin-Dependent Kinase 5; Female; Guanylate Kinase; Hippocampus; Male; Membrane Proteins; Mice; Mice, Knockout; Neurons; Organ Culture Techniques; Protein Interaction Mapping; Ubiquitination

Disciplines

Cell Biology

Abstract

Cyclin-dependent kinase 5 (Cdk5) and its activator p35 have been implicated in drug addiction, neurodegenerative diseases such as Alzheimer's, learning and memory, and synapse maturation and plasticity. However, the molecular mechanisms by which Cdk5 regulates synaptic plasticity are still unclear. PSD-95 is a major postsynaptic scaffolding protein of glutamatergic synapses that regulates synaptic strength and plasticity. PSD-95 is ubiquitinated by the ubiquitin E3 ligase Mdm2, and rapid and transient PSD-95 ubiquitination has been implicated in NMDA receptor-induced AMPA receptor endocytosis. Here we demonstrate that genetic or pharmacological reduction of Cdk5 activity increases the interaction of Mdm2 with PSD-95 and enhances PSD-95 ubiquitination without affecting PSD-95 protein levels in vivo in mice, suggesting a nonproteolytic function of ubiquitinated PSD-95 at synapses. We show that PSD-95 ubiquitination correlates with increased interaction with beta-adaptin, a subunit of the clathrin adaptor protein complex AP-2. This interaction is increased by genetic reduction of Cdk5 activity or NMDA receptor stimulation and is dependent on Mdm2. Together these results support a function for Cdk5 in regulating PSD-95 ubiquitination and its interaction with AP-2 and suggest a mechanism by which PSD-95 may regulate NMDA receptor-induced AMPA receptor endocytosis.

Rights and Permissions

Citation: J Neurosci. 2011 Aug 17;31(33):12029-35. Link to article on publisher's site

Comments

Copyright © 2011 the authors. Copyright of all material published in The Journal of Neuroscience remains with the authors. The authors grant the Society for Neuroscience an exclusive license to publish their work for the first 6 months. After 6 months the work becomes available to the public to copy, distribute, or display under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 Unported license.

Related Resources

Link to Article in PubMed

PubMed ID

21849563

Included in

Cell Biology Commons

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