Abstract
Dauer pheromones or daumones, which are signaling molecules that interrupt development and reproduction (dauer larvae) during unfavorable growth conditions, are essential for cellular homeostasis in Caenorhabditis elegans. According to earlier studies, dauer larva formation in strain N2 is enhanced by a temperature increase, suggesting the involvement of a temperature-dependent component in dauer pheromone biosynthesis or sensing. Several naturally occurring daumone analogs (e.g. daumones 1-3) have been identified, and these molecules are predicted to be synthesized in different physiological settings in this nematode. To elucidate the molecular regulatory system that may influence the dynamic balance of specific daumone production in response to sudden temperature changes, we characterized the peroxisomal acox gene encoding acyl-CoA oxidase, which is predicted to catalyze the first reaction during biosynthesis of the fatty acid component of daumones. Using acox-1(ok2257) mutants and a new, robust analytical method, we quantified the three most abundant daumones in worm bodies and showed that acox likely contributes to the dynamic production of various quantities of three different daumones in response to temperature increase, changes that are critical in C. elegans for coping with the natural environmental changes it faces.