Head grooming in Drosophila consists of repeated sweeps of the legs across the head, comprising regular cycles. We used the GAL4-UAS system to study the effects of overexpressing shibire^ts1 and of Adar knockdown via RNA interference, on the period of head-grooming cycles in Drosophila. Overexpressing shibire^ts1 interferes with synaptic vesicle recycling and thus with cell communication, while Adar knockdown reduces RNA editing of neuronal transcripts for a large number of genes. All transgenic flies and their controls were tested at 22° to avoid temperature effects; in wild type, cycle frequency varied with temperature with a Q₁₀ of 1.3. Two experiments were performed with transgenic shibire^ts1: (1) each fly was heat-shocked for 10 min at 30° immediately before testing at 22° and (2) flies were not heat shocked. In both experiments, cycle period was increased when shibire^ts1 was overexpressed in all neurons, but was not increased when shibire^ts1 was overexpressed in motoneurons alone. We hypothesize that grooming cycles in flies overexpressing shibire^ts1 are lengthened because of synaptic impairment in neural circuits that control head-grooming cycles. In flies with constitutive, pan-neuronal Adar knockdown, cycle period was more variable within individuals, but mean cycle period was not significantly altered. We conclude that RNA editing is essential for the maintenance of within-individual stereotypy of head-grooming cycles.

果蝇的头部梳理包括用腿反复扫过头部，形成有规律的循环。我们使用GAL4-UAS系统研究过表达shibire ^ts1和通过 RNA 干扰敲低Adar对果蝇头部梳理周期的影响。过度表达shibire ^ts1会干扰突触小泡回收，从而干扰细胞通讯，而Adar敲低则会减少大量基因的神经元转录本的 RNA 编辑。所有转基因果蝇及其对照均在 22° 下进行测试，以避免温度影响；在野生型中，循环频率随温度变化，Q ₁₀为1.3。使用转基因shibire ^ts1进行了两个实验：(1) 每只果蝇在 22° 下测试之前立即在 30° 下热休克 10 分钟，(2) 果蝇未进行热休克。在这两个实验中，当shibire ^ts1在所有神经元中过表达时，循环周期增加，但当shibire ^ts1仅在运动神经元中过表达时，循环周期不增加。我们假设，过度表达shibire ^ts1的果蝇的理毛周期会延长，因为控制头部理毛周期的神经回路中的突触受损。在具有组成型、全神经元Adar敲低的果蝇中，周期周期在个体内变化更大，但平均周期周期没有显着改变。我们得出的结论是，RNA 编辑对于维持个体内部的头部梳理周期刻板印象至关重要。