Morning and evening activity peaks depend on different brain clock neurons in fruit flies

Restoring PER protein expression in specific neurons can restore morning and evening activity patterns in Drosophila.

• The brain's circadian clock in Drosophila controls locomotor activity through groups of neurons that express the Period (PER) protein.
• Targeted expression of PER in LN(v) neurons restores morning activity, while expression in both LN(v) and LN(d) neurons restores evening activity.
• This research identifies distinct neuronal bases for morning and evening activity patterns in Drosophila.
• LN(v) neurons alone are capable of generating 24-hour activity rhythms even in constant darkness.

Simplified