Molecular identification and lipid mobilization role of adipokinetic hormone receptor in (F.).

Energy homeostasis is essential for organisms to maintain fluctuation in energy accumulation, mobilization. Lipids as the main energy reserve in insects, their metabolism is under the control of many physiological program. This study aimed to determine whether the adipokinetic hormone receptor (AKHR) was involved in the lipid mobilization in the . A full-length cDNA encoding AKHR was isolated from . The AKHR protein has a conserved seven-transmembrane domain which is the character of a putative G protein receptor. Expression profile investigation revealed that mRNA was highly expressed in immatural stage and abundant in fat body in newly emerged female adults. Knockdown of expression was achieved through RNAi by injecting double-stranded RNA (dsRNA) into the 6th instar larvae. The content of triacylgycerol (TAG) in the fat body increased significantly after the gene was knockdown. And decrease of TAG releasing to hemolymph with increase of free fatty acid (FFA) in hemolymph were observed when the gene was knowned-down. In addition, lipid droplets increased in fat body was also found. These results suggested that SlAKHR is critical for insects to regulate lipids metabolism.