Fluorescent Tools for Studying Daily Biological Rhythms in Fruit Flies

The use of destabilized GFP (dGFP) allows for tracking transcriptional activity of the circadian clock in Drosophila melanogaster with ~1-h temporal resolution.

• Circadian rhythms involve daily fluctuations in physiology and gene expression regulated by a feedback loop known as the circadian clock.
• In Drosophila, the core clock consists of the transcription factors clock (Clk) and cycle (cyc), which activate their own repressors, period (per) and timeless (tim).
• The circadian clock operates on a roughly 24-hour cycle, continuing even without external cues.
• Rapidly degraded fluorescent protein reporters enable in vivo assessment of transcriptional activity at the single-cell level.
• The methods developed can be applied to study circadian clock activity in various tissues beyond the intestine.

Simplified