FoxO6 regulates memory consolidation and synaptic function.. Mus musculus

We used microarrays to assess gene expression differences in the hippocampus between FoxO6 mutant and wild-type siblings before (basal) or after novel object learning. Overall design: The cohort of basal mice were housed individually for at least 3 days prior to tissue harvesting. The mice used to collect hippocampal samples after the object learning task were handled daily in the procedure room, prior to the object learning task. 24 hours before the object learning task, each mouse was individually habituated to the empty novel object arena for 10 min. On the days of the novel object learning task and the empty arena habituation, the mice were transferred to the procedure room and acclimatized for 60 min. For the novel object learning task, the mice were allowed to explore two identical and novel objects for 10 min in a 70 x 70 x 70 cm black plastic arena with a white PVC vinyl material on the base. After the object exploration, mice were transferred to an empty cage, and were euthanized after 60 min. The brains were dissected and incubated in ice-cold RNAlater (Ambion) for 24 hours at 4ºC. The brains were then rapidly frozen in O.C.T. Tissue-Tek (Sakura) at -80ºC. Coronal brain sections (300 µm) were made using a microtome (Microm), the hippocampus was finely dissected and collected into ‘RNA lysis buffer’ (Ambion), and homogenized for 30 sec using a rotar-stat homogenizer. Total RNA was extracted using the RNAqueous column (Ambion) following the manufacturer’s protocol.