The acetyltransferase chameau (chm) functions as metabolic sensor in regulating energy homeostasis and starvation response in Drosophila melanogaster

The coupling of metabolism to the posttranslational modification of proteins has been suggested to play an important role in the modulation of protein function in response to physiological variation. This interplay could potentially establish feedback loops that buffer extreme environmental challenges. Protein acetylation is one such posttranslational protein modification that is tightly coupled to metabolic variation. Here, we show that the acetyltransferase chameau (chm), which affects life span in Drosophila, is also involved in the regulation of metabolism upon environmental cues. While chm haploinsufficiency increases life span in flies that have sufficient access to nutrients, it reduces their ability to cope with starvation. We hypothesize the starvation susceptibility in mutant flies is caused by their reduced ability to modulate energy homeostasis. Interestingly, this effect is highly dependent on the ambient temperature, suggesting that it evolved to allow organisms to adapt to a wider range of environmental conditions by modulating their energy metabolism.