A role for dendritic translation of CaMKII? mRNA in olfactory plasticity.

ABSTRACT: Local protein synthesis in dendrites contributes to the synaptic modifications underlying learning and memory. The mRNA encoding the ? subunit of the calcium/calmodulin dependent Kinase II (CaMKII?) is dendritically localized and locally translated. A role for CaMKII? local translation in hippocampus-dependent memory has been demonstrated in mice with disrupted CaMKII? dendritic translation, through deletion of CaMKII? 3'UTR. We studied the dendritic localization and local translation of CaMKII? in the mouse olfactory bulb (OB), the first relay of the olfactory pathway, which exhibits a high level of plasticity in response to olfactory experience. CaMKII? is expressed by granule cells (GCs) of the OB. Through in situ hybridization and synaptosome preparation, we show that CaMKII? mRNA is transported in GC dendrites, synaptically localized and might be locally translated at GC synapses. Increases in the synaptic localization of CaMKII? mRNA and protein in response to brief exposure to new odors demonstrate that they are activity-dependent processes. The activity-induced dendritic transport of CaMKII? mRNA can be inhibited by an NMDA receptor antagonist and mimicked by an NMDA receptor agonist. Finally, in mice devoid of CaMKII? 3'UTR, the dendritic localization of CaMKII? mRNA is disrupted in the OB and olfactory associative learning is severely impaired. Our studies thus reveal a new functional modality for CaMKII? local translation, as an essential determinant of olfactory plasticity.

SUBMITTER: Neant-Fery M 

PROVIDER: S-EPMC3387027 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature