Temperature sensitivity of circadian clocks is conserved across Drosophila species melanogaster, malerkotliana and ananassae

Abstract

Light and temperature are the major environmental cycles that can synchronize circadian rhythms in a variety of organisms. Previously, we have shown that under light/dark cycles of various photoperiods, the Drosophila species ananassae exhibits unimodal activity pattern with a prominent morning activity peak in contrast with Drosophila melanogaster and Drosophila malerkotliana, which show bimodal activity pattern with morning and evening activity peaks. Here we report that circadian clocks controlling activity/rest rhythm of these two less-studied species D. malerkotliana and D. ananassae can be synchronized by temperature cycles and that even under temperature cycles D. ananassae exhibits only a pronounced morning (thermophase onset) activity peak. Although D. melanogaster and D. ananassae exhibit differences in the phase of activity/rest rhythm under temperature cycles, circadian clocks of both show similar sensitivity to warm temperature pulses. Circadian period of activity/rest rhythm of D. ananassae differs from the other two species at some moderate-range temperatures; however, in conditions that are more extreme, circadian clocks of D. melanogaster, D. malerkotliana and D. ananassae appear to be largely temperature compensated.

• Circadian
• melanogaster
• temperature cycles
• temperature compensation

Acknowledgments

We thank three anonymous reviewers for reading our manuscript and suggesting some very useful changes. Sudeshna Das is acknowledged for the collection of flies and Rajanna and Muniraju for technical assistance. We thank Vijay Kumar Sharma and Pavitra Prakash for their comments and suggestions.

Supplementary material available online

Supplementary Figures 1–3