Protocol for cell-type-specific circadian bioluminescence recording from mouse gut muscularis externa explants

Cell-type-specific circadian recording is essential for understanding tissue-level circadian organization. This protocol describes the generation of intestinal cell-type-specific PER2::CBG-LUC reporter mice, preparation of intestinal longitudinal muscle-myenteric plexus explants, long-term bioluminescence recording using photomultiplier-based photon counting system, and analysis of circadian phase and rhythmicity. The protocol also includes procedures to verify that ex vivo rhythms reflect the endogenous in vivo circadian phase. For complete details on the execution of this protocol, please refer to Magaña et al.¹.