Synchronized fruit fly body clocks show different calcium rhythms inside living flies

Daily rhythmic changes in intracellular calcium levels in pacemaker neurons were observed over 24 hours.

• Pacemaker neurons in Drosophila exhibit calcium fluctuations that are influenced by environmental cues.
• Each group of pacemaker neurons activates at different phases, indicating asynchronous behavior.
• Calcium rhythms related to morning and evening activities occur approximately 4 hours prior to these behaviors.
• Loss of the receptor for the neuropeptide PDF leads to synchronized calcium wave patterns among the neurons.
• Neuropeptide modulation plays a crucial role in timing the outputs of these molecular pacemaker networks.

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