miR-124 acts During Drosophila Development to Determine the Phase of Adult Circadian Behavior

Loss of the microRNA results in significant miswiring within the circadian neural network.

• Circadian misalignment may negatively impact animal wellbeing and survival.
• Loss of the microRNA advances evening locomotor activity by several hours in constant darkness.
• Under a light/dark cycle with a short photoperiod, loss of the microRNA delays morning activity.
• Elimination of the microRNA during larval development leads to opposite phase phenotypes, but not when lost during pupation to adulthood.
• The loss of the microRNA alters activity rhythms in specific neurons that control morning and evening activity.
• Silencing certain neurons in mutant flies can restore evening activity timing, while activating others can rescue both morning and evening timing.

AI simplified