Circadian clock genes in Drosophila: recent developments.

Circadian rhythms are established in a majority of eukaryotes and some prokaryotes.

• The core mechanism of circadian clocks involves a feedback loop with period, timeless, dclock, and cycle genes.
• Multiple feedback loops have been identified that control rhythm generation and expression in Drosophila melanogaster.
• Novel mutations of timeless provide insights into the functions of period and timeless gene products.
• The pdf neuropeptide gene acts as the main circadian transmitter in circadian pacemaker cells.
• Cryptochrome functions both as a circadian photoreceptor and as a component of the circadian clock.
• The specific genes and products that transmit environmental information to the clock remain to be identified.

AI simplified