MOIRA is required for clock protein and gene clustering and normal circadian rhythms in Drosophila [RNA-seq]

Circadian clocks are ~24-hour timekeepers that orchestrate daily rhythms in the expression of a multitude of genes, thereby influencing a wide array of physiological processes from sleep to metabolism. The chromatin at clock-controlled genes undergoes rhythmic modifications facilitated by the activities of histone modifiers and chromatin-remodeling proteins. However, despite its significance, this area of research remains relatively under explored. Our recent investigations unveiled that Moira, a component of ATP-dependent chromatin remodeling complex SWI/SNF complex is essential for generating ~24-h circadian rhythms in Drosophila Melanogaster. Moira functions specifically as a repressor for clock regulated genes by compacting chromatin in clock neurons. The rhythm of chromatin accessibility is completely abolished in the absence of Moira. Further, Moira is organized into ~10 positionally static, discrete nuclear foci at the inner nuclear envelope across all Drosophila cells, and clock regulated genes are localized to one of these Moira foci throughout the circadian cycle specifically in the clock neurons. Our study will lead to a significant advancement in our understanding of how SWI/SNF complexes regulate chromatin structure and subnuclear localization of clock-regulated genes, and ultimately affect circadian rhythms. Overall design: 1) polyA RNA sequencing of Drosophila melanogaster clock neurons in control and mor-RNAi knockdown, and 2) ATAC-seq of Drosophila melanogaster clock neurons in control and mor-RNAi knockdown. Cells were isolated by fluorescence-activated cell sorting (FACS) using Clk-GAL4>UAS-GFP-NLS line developed in the lab. GFP-positive and DAPI-negative cells were sorted to be clock neurons.