title: RNA interference unveils functions of the hypertrehalosemic hormone on cyclic fluctuation of hemolymph trehalose and oviposition in the virgin female Blattella germanica.
abstract: Hypertrehalosemic hormone (HTH) is a neuropeptide within the adipokinetic hormone (AKH) family that induces a release of trehalose from fat body into hemolymph in a number of insects. In this study, we first showed that female adult German cockroach, Blattella germanica, displayed a cyclic fluctuation of hemolymph trehalose levels correlated to the maturation of oocytes in the reproductive cycle. After cloning the HTH cDNA from the German cockroach (Blage-HTH), expression studies indicated that Blage-HTH mRNA showed the cyclic changes during the first reproductive cycle, where peak values occurred in 8-day-old virgin female cockroaches, which were going to produce oothecae. The functions of Blage-HTH were studied using RNA interference (RNAi) to knockdown its expression. Adult virgin females of B. germanica injected with Blage-HTH dsRNA increased hemolymph trehalose levels in the late period of vitellogenesis more slowly than control. Furthermore, RNAi of Blage-HTH delayed oviposition time and some (10%) individuals did not produce the first ootheca until 15 days after eclosion, whereas the control group produced ootheca before 9 days in all cases.
authors: Department of Entomology, National Taiwan University, Taipei 106, Taiwan.
authors: Jia-Hsin
authors: JH
authors: Huang
authors: How-Jing
authors: HJ
authors: Lee
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D020048:Blattellidae / Q000235:genetics / Q000502:physiology*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D005260:Female; D055785:Gene Knockdown Techniques; D006458:Hemolymph / Q000378:metabolism*; D008969:Molecular Sequence Data; D009479:Neuropeptides / Q000235:genetics / Q000378:metabolism*; D009865:Oocytes / Q000502:physiology; D010058:Oviposition; D016133:Polymerase Chain Reaction; D034622:RNA Interference; D012333:RNA, Messenger / Q000235:genetics; D012098:Reproduction; D014199:Trehalose / Q000032:analysis / Q000378:metabolism*; D014818:Vitellogenesis
chemical_list: D018076:DNA, Complementary; D009479:Neuropeptides; D012333:RNA, Messenger; C084112:hypertrehalosemic hormone; D014199:Trehalose