This study aimed to investigate alterations in the activity and sleep of Drosophila melanogaster under simulated microgravity, which was implemented through the random positioning machine, while different light conditions (normal photoperiod and constant dark) were set. Fruit flies of different strains and sexes were treated for 3 days, and activity and sleep were monitored using the Drosophila Activity Monitoring System. After 3 days of treatment, fruit flies were sampled to detect the relative expression levels of the major clock genes and some neurotransmitter-related genes. The results showed that for the normal photoperiod (LD) condition, the activity increased and sleep decreased under simulated microgravity, while for the constant dark (DD) condition, the activity and sleep rhythms appeared disordered and the activity increased, thus decreasing the likelihood of waking up during the day. Light conditions, strains, and sexes, individually or in combination, had impacts on the simulated microgravity effects on behaviors. The clock genes and neurotransmitter-related genes had different degrees of response among sexes and strains, although the overall changes were slight. The results indicated that the normal photoperiod could ease the effects of simulated microgravity on fruit flies’ activity and sleep and possible unidentified pathways involved in the regulatory mechanism need further exploration. This study is expected to provide ideas and references for studying the effects of microgravity on space life science.

本研究旨在调查黑腹果蝇的活动和睡眠的变化在模拟微重力下，通过随机定位机实现，同时设置不同的光照条件（正常光周期和恒定黑暗）。不同品系和性别的果蝇被处理 3 天，并使用果蝇活动监测系统监测活动和睡眠。处理3天后，对果蝇进行采样，检测主要时钟基因和一些神经递质相关基因的相对表达水平。结果表明，对于正常光周期（LD）条件，模拟微重力下活动增加，睡眠减少，而对于恒定黑暗（DD）条件，活动和睡眠节律出现紊乱，活动增加，从而降低了白天醒来。光照条件、菌株和性别，单独或组合，对模拟微重力对行为的影响产生影响。生物钟基因和神经递质相关基因在不同性别和菌株之间有不同程度的反应，尽管总体变化很小。结果表明，正常光周期可以缓解模拟微重力对果蝇活动和睡眠的影响，调控机制中可能涉及的未知途径需要进一步探索。该研究有望为研究微重力对空间生命科学的影响提供思路和参考。结果表明，正常光周期可以缓解模拟微重力对果蝇活动和睡眠的影响，调控机制中可能涉及的未知途径需要进一步探索。该研究有望为研究微重力对空间生命科学的影响提供思路和参考。结果表明，正常光周期可以缓解模拟微重力对果蝇活动和睡眠的影响，调控机制中可能涉及的未知途径需要进一步探索。该研究有望为研究微重力对空间生命科学的影响提供思路和参考。