Abstract
Rhythmic behaviors regulated by the circadian clock are essential for living creatures and Drosophila is an ideal model in which to study them. About 150 neuron control circadian rhythms housed in the Drosophila brain, and they rely on molecules like neuropeptides to communicate with each other to be synchronous. Only seven neuropeptides have been identified within clock neurons so far. CG17777 is a candidate novel neuropeptide that is expressed in the circadian network including the LNds, DN1as and possibly the LNvs and DN1s. CRISPR deletion of CG17777 showed hyperactivity specifically during the day. Knockdown of CG17777 using RNAi in the central clock or eyes might be responsible for a higher activity in the evening period. Thus, we concluded that CG17777 might represses daytime activity in Drosophila. Interestingly, when knocking down CG17777 in two of the LNds cells, the flies showed less daytime activity. CG17777 might play different roles in different neurons. Also, circadian period of CG17777 knockdown or CRISPR deletion files is normal, so CG17777 may not regulate periods alone.