No abstract

Sleep is regulated by two main processes: the circadian clock and sleep homeostasis. Circadian rhythms have been well studied at the molecular level. In the Drosophila circadian clock neurons, the core clock proteins are precisely regulated by post-translational modifications and degraded via the ubiquitinproteasome system (UPS). Sleep homeostasis, however, is less understood; nevertheless, recent reports suggest that proteasome-mediated degradation of core clock proteins or synaptic proteins contributes to the regulation of sleep amount. Here, we review the molecular mechanism of the UPS and summarize the role of protein degradation in the regulation of circadian clock and homeostatic sleep in Drosophila. Moreover, we discuss the potential interaction between circadian clock and homeostatic sleep regulation with a prime focus on E3 ubiquitin ligases.

Bioluminescence generated by luciferase and luciferin has been extensively used in biological research. However, detecting signals from deep tissues in vivo poses a challenge to traditional methods. To overcome this, the Akaluc and AkaLumine bioluminescent systems were developed, resulting in improved signal detection. We evaluated the potential of Akaluc/AkaLumine in Drosophila melanogaster to establish a highly sensitive, non-invasive, and temporal detection method for gene expression. Our results showed that oral administration of AkaLumine to flies expressing Akaluc provided a higher luminescence signal than Luc/D-luciferin, with no observed harmful effects on flies. The Akaluc/AkaLumine system allows for monitoring of dynamic temporal changes in gene expression. Additionally, using the Akaluc fusion protein and fusion gene allows for protein level and mRNA splicing monitoring. Our findings indicate that the Akaluc/AkaLumine system is a powerful bioluminescence tool for analyzing gene and protein expression in deep tissues and small numbers of cells in Drosophila.