Synapse-associated protein-97 mediates alpha-secretase ADAM10 trafficking and promotes its activity

Department of Pharmacological Sciences and Centre of Excellence on Neurodegenerative Diseases, University of Milan, 20133 Milan, Italy.
The Journal of Neuroscience : The Official Journal of the Society for Neuroscience (Impact Factor: 6.75). 03/2007; 27(7):1682-91. DOI: 10.1523/JNEUROSCI.3439-06.2007
Source: PubMed

ABSTRACT Alzheimer's disease (AD) is a chronic neurodegenerative disorder caused by a combination of events impairing normal neuronal function. Here we found a molecular bridge between key elements of primary and secondary pathogenic events in AD, namely the elements of the amyloid cascade and synaptic dysfunction associated with the glutamatergic system. In fact, we report that synapse-associated protein-97 (SAP97), a protein involved in dynamic trafficking of proteins to the excitatory synapse, is responsible for driving ADAM10 (a disintegrin and metalloproteinase 10, the most accredited candidate for alpha-secretase) to the postsynaptic membrane, by a direct interaction through its Src homology 3 domain. NMDA receptor activation mediates this event and positively modulates alpha-secretase activity. Furthermore, perturbing ADAM10/SAP97 association in vivo by cell-permeable peptides impairs ADAM10 localization in postsynaptic membranes and consequently decreases the physiological amyloid precursor protein (APP) metabolism. Our findings indicate that glutamatergic synapse activation through NMDA receptor promotes the non-amyloidogenic APP cleavage, strengthening the correlation between APP metabolism and synaptic plasticity.

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