title: Neurone specific regulation of dendritic spines in vivo by post synaptic density 95 protein (PSD-95).
abstract: Post synaptic density protein 95 (PSD-95) is a postsynaptic adaptor protein coupling the NMDA receptor to downstream signalling pathways underlying plasticity. Mice carrying a targeted gene mutation of PSD-95 show altered behavioural plasticity including spatial learning, neuropathic pain, orientation preference in visual cortical cells, and cocaine sensitisation. These behavioural effects are accompanied by changes in long-term potentiation of synaptic transmission. In vitro studies of PSD-95 signalling indicate that it may play a role in regulating dendritic spine structure. Here, we show that PSD-95 mutant mice have alterations in dendritic spine density in the striatum (a 15% decrease along the dendritic length) and in the hippocampus (a localised 40% increase) without changes in dendritic branch patterns or gross neuronal architecture. These changes in spine density were accompanied by altered expression of proteins known to interact with PSD-95, including NR2B and SAP102, suggesting that PSD-95 plays a role in regulating the expression and activation of proteins found within the NMDA receptor complex. Thus, PSD-95 is an important regulator of neuronal structure as well as plasticity in vivo.
authors: Department of Pre-Clinical Veterinary Sciences, (RDSVS) Summerhall, University of Edinburgh, Edinburgh. EH9 1QH, UK. Cathy.Vickers@ed.ac.uk
authors: Catherine A
authors: CA
authors: Vickers
authors: Benjamin
authors: B
authors: Stephens
authors: Julian
authors: J
authors: Bowen
authors: Gordon W
authors: GW
authors: Arbuthnott
authors: Seth G N
authors: SG
authors: Grant
authors: Cali A
authors: CA
authors: Ingham