RT Journal Article
SR Electronic
T1 Octopamine connects nutrient cues to lipid metabolism upon nutrient deprivation
JF Science Advances
JO Sci Adv
FD American Association for the Advancement of Science
SP e1501372
DO 10.1126/sciadv.1501372
VO 2
IS 5
A1 Tao, Jun
A1 Ma, Yi-Cheng
A1 Yang, Zhong-Shan
A1 Zou, Cheng-Gang
A1 Zhang, Ke-Qin
YR 2016
UL http://advances.sciencemag.org/content/2/5/e1501372.abstract
AB Starvation is probably the most common stressful situation in nature. In vertebrates, elevation of the biogenic amine norepinephrine levels is common during starvation. However, the precise role of norepinephrine in nutrient deprivation remains largely unknown. We report that in the free-living nematode Caenorhabditis elegans, up-regulation of the biosynthesis of octopamine, the invertebrate counterpart of norepinephrine, serves as a mechanism to adapt to starvation. During nutrient deprivation, the nuclear receptor DAF-12, known to sense nutritional cues, up-regulates the expression of tbh-1 that encodes tyramine β-hydroxylase, a key enzyme for octopamine biosynthesis, in the RIC neurons. Octopamine induces the expression of the lipase gene lips-6 via its receptor SER-3 in the intestine. LIPS-6, in turn, elicits lipid mobilization. Our findings reveal that octopamine acts as an endocrine regulator linking nutrient cues to lipolysis to maintain energy homeostasis, and suggest that such a mechanism may be evolutionally conserved in diverse organisms.