Chameau (HBO1) regulates starvation in a temperature-dependent manner in Drosophila melanogaster

The body temperature of Drosophila melanogaster depends on the extrinsic temperature. Numerous studies in fruit flies have shown that environmental temperature has an effect on metabolism, lifespan and starvation resilience. We have previously shown that Chameau (Chm), a MYST-domain acetyltransferase, promotes aging but also increases starvation resilience. As starvation resilience is highly temperature dependent, we explored the effect of temperature on starvation resilience in fruit flies with reduced chm expression. Strikingly, we found that an increase of 2{degrees}C was sufficient to restore starvation resilience in chm mutants. The increase in temperature rescued the dampened expression of genes involved in insulin, hormone and starvation response as well as a reduced rate of weight loss and misregulation of trehalose, which we observed in chm mutants at 23{degrees}C. Our data show that whereas Chm has an important role in regulating starvation at 23{degrees}C and below, it becomes obsolete at higher temperatures. Our finding that a gene plays an important role only under specific environmental conditions has important implications in light of the recent global change of climate conditions.