Cuticular hydrocarbons promote desiccation resistance by preventing transpiration in Drosophila melanogaster.

Desiccation is a fundamental challenge confronted by all terrestrial organisms, particularly insects. With a relatively small body size and large surface-to-volume ratio, insects are susceptible to rapid evaporative water loss and dehydration. To counter these physical constraints, insects have acquired specialized adaptations, including a hydrophobic cuticle that acts as a physical barrier to transpiration.

UBR4/POE facilitates secretory trafficking to maintain circadian clock synchrony.

Ubiquitin ligases control the degradation of core clock proteins to govern the speed and resetting properties of the circadian pacemaker. However, few studies have addressed their potential to regulate other cellular events within clock neurons beyond clock protein turnover. Here, we report that the ubiquitin ligase, UBR4/POE, strengthens the central pacemaker by facilitating neuropeptide trafficking in clock neurons and promoting network synchrony.

Desiccation resistance is an adaptive life-history trait dependent upon cuticular hydrocarbons, and influenced by mating status and temperature in D. melanogaster.

Terrestrial insects are susceptible to desiccation and conserve internal water stores by preventing the loss of water due to transpiration across the cuticle. The epicuticle, a thin waxy layer on the outer surface of the insect cuticle is comprised primarily of a complex blend of cuticular hydrocarbons (CHCs) and is integral to preventing cuticular water loss. How the composition of epicuticular lipids (quantity and quality of the specific hydrocarbons) relates to desiccation resistance, however, has been difficult to determine.