A Hsp70 promoter drives expression of the Mmus\fabp7 open-reading frame.
Overexpression of Mmus\fabp7hs.PG results in a dramatic reduction in baseline sleep relative to controls, principally from decreased daytime sleep. The average daytime bout length and the average maximum daytime bout length are both significantly reduced in these mutants. This reduction in daytime sleep is not due to hyperactivity, since daytime locomotor activity, as measured by counts per waking minute, is reduced in these flies. The total number of sleep bouts over a 24 hour period was not different from controls. Mmus\fabp7hs.PG induction increases the maximum daytime bout length or bout number compared to controls. Increasing the temperature from 20[o]C to 30[o]C increases Mmus\fabp7hs.PG expression resulting in a correlated net increase in longer daytime sleep bouts.
Trained Mmus\fabp7hs.PG flies maintained at 20[o]C do not show any changes in long-term memory formation compared to controls. However, inducing Mmus\fabp7hs.PG overexpression in flies stored at 30[o]C during the maintenance period following training show a significant enhancement of 7-day long-term memory. Learning scores for these flies were as in controls. Mmus\fabp7hs.PG induction increases the maximum daytime bout length or bout number compared to controls. Increasing the temperature from 20[o]C to 30[o]C increases Mmus\fabp7hs.PG expression resulting in a correlated net increase in longer daytime sleep bouts.
Induction of Mmus\fabp7hs.PG immediately after behavioral training does not enhance 24-hour memory.
Mmus\fabp7hs.PG flies trained at 25[o]C that are immediately placed at 30[o]C for four days and then shifted back to 25[o]C for the remaining time exhibit preserved memory enhancement. Shifting the overexpression window to a later consolidation period (between post-training days 2 and 7) also preserves enhancement of long-term memory in Mmus\fabp7hs.PG flies. These flies show elevated olfactory avoidance responses following five days at 30[o]C, but still show an increase in long-term memory when shifted back to 20[o]C for two days prior to testing. Acute induction of Mmus\fabp7hs.PG two hours prior to testing for long-term memory actually inhibits performance.
Mmus\fabp7hs.PG flies maintained at 30[o]C for four consecutive days following two days baseline at 20[o]C display a significant increase in minutes and percentage of sleep gained compared to controls on the second, third and fourth days at 30[o]C. The cumulative increase in total sleep and percentage of total sleep gained is significantly higher in these flies compared to controls. This increase in cumulative sleep during the consolidation period correlates with an enhancement in long-term memory performance.
Mmus\Fabp7hs.PG, Scer\GAL4elav-C155 is a suppressor of abnormal sleep | adult stage phenotype of Hsap\APPAβ42.UAS.Tag:SS(rPENK), Scer\GAL4elav-C155
The sleep loss and fragmentation induced by Scer\GAL4elav-C155-driven expression of Hsap\APPAβ42.Scer\UAS.T:Rnor\SS-PENK are rescued by co-expression of Mmus\Fabp7hs.PG.