Circadian clock gene is involved in the photoperiodic response of the Spodoptera litura adults

Abstract

Circadian clocks govern many metabolic and behavioural processes in an organism. In insects, these clocks and their molecular machinery have been found to influence reproduction in many different ways. In moth Spodoptera litura, we demonstrated the occurrence of circadian clock genes in adult’s heads. We identified different clock genes, period (per), cryptochrome1 (cry1) and cryptochrome2 (cry2) in adult heads, using real-time PCR. Our results show that Cry1 gene and Period gene expression level is high at 8:16 photoperiod as compared with other photoperiod. In Cry2, gene expression level is high at 8:16 and 0:24 photoperiod. We show that expression levels of the clock genes per, cry1 and cry2 fluctuate in a circadian manner in adult heads in S. litura. These results strongly suggest that the occurrence of a circadian clock in S. litura heads.

Keywords:

• circadian clock
• Spodoptera litura
• real-time PCR
• adult heads

Acknowledgements

We acknowledge the funding provided by the University Grants Commission India (file No. 42-201/2013) and the Department of Biotechnology, Periyar University, Salem, for providing fellowship (URF) and infrastructure facilities for carrying out this research work.