Neuropeptide F Protects Memory Impairment Induced By Chronic Stress In Drosophila Melanogaster

Animals adapt to stress conditions by changing their behaviors.Those changes can have diverse impacts,from affecting the quality of life to affecting survival.In recently years,stress research has caught a lot of attentions.However,little is known about the molecule and neural circuit mechanism of stress induced behavioral changes.Here,we established a novel Drosophila chronic stress model by using mechanic shock as a stressor to study this topic.I took advantage of the Drosophila molecular genetic tools and identified neuropeptide F as a major factor for chronic stress regulation.Although no neuronal cell death was detected in the brain after chronic MS stress,the flies showed severe deficits in short term memory and middle term memory,changed their alcohol preference as well.In the early phase of the chronic stress treatment,MS induces the expression of NPF gene.NPF expression reaches its peak after 2-3 days of MS treatment and then starts to decrease.Eventually,the expression level was remarkably lower than the untreated control group.The NPF expression remains low even after the treatment was finished.Knocking down NPF expression with RNAi technique results in memory deficit,suggests that NPF mediates the chronic stressed induced memory impairments.This hypothesis was verified by the observation that NPF overexpression rescues the chronic MS stress induced memory loss.Thus,NPF plays a positive role in protecting memory impairments upon stress insult.