Acute disruption of the NMDA receptor subunit NR1 in the honeybee brain selectively impairs memory formation.

Memory formation is a continuous process composed of multiple phases that can develop independently from each other. These phases depend on signaling pathways initiated after the activation of receptors in different brain regions. The NMDA receptor acts as a sensor of coincident activity between neural inputs, and, as such, its activation during learning is thought to be crucial for various forms of memory. In this study, we inhibited the expression of the NR1 subunit of the NMDA receptor in the honeybee brain using RNA interference. We show that the disruption of the subunit expression in the mushroom body region of the honeybee brain during and shortly after appetitive learning selectively impaired memory. Although the formation of mid-term memory and early long-term memory was impaired, late long-term memory was left intact. This indicates that late long-term memory formation differs in its dependence on NMDA receptor activity from earlier memory phases.