Expression of juvenile hormone acid O-methyltransferase and juvenile hormone synthesis in Blattella germanica

作     者：Claudia V. Dominguez Jose L. Maestro 

作者机构：Institute of Evolutionary Biology CSIC-Universitat Pompeu Fabra Barcelona Spain 

出 版 物：《Insect Science》 (昆虫科学（英文版）)

年 卷 期：2018年第25卷第5期

页      面：787-796页

核心收录：

学科分类：0710[理学-生物学] 1007[医学-药学(可授医学、理学学位)] 100705[医学-微生物与生化药学] 071010[理学-生物化学与分子生物学] 0830[工学-环境科学与工程（可授工学、理学、农学学位）] 07[理学] 0904[农学-植物保护] 0901[农学-作物学] 10[医学] 0713[理学-生态学] 

基　　金：supported by grants (Spanish Ministry of Science and Innovation [MICINN]) Spanish Ministry of Economy and Competitiveness (MINECO) and FEDER (Secretaria d'Universitats i Recerca, Catalan Goverment) to J.L.M 

主　　题：Blattella germanica corpora allata JHAMT juvenile hormone nutritionalsignaling 

摘      要：Juvenile hormone （JH）, a sesquiterpenoid synthetized by the insect corpora allata （CA）, plays critical roles in metamorphosis and reproduction. Penultimate or last step of JH synthesis is catalyzed by juvenile hormone acid O-methyltransferase （JHAMT）. Here we report the cloning and expression analysis of the JHAMT orthologue in the cockroach, Blattella germanica （L.） （BgJHAMT）. BgJHAMT is mainly expressed in CA, with only expression traces in ovary. Three different isoforms, differing in the 3＇-UTR sequence, were identified. Isoform A shows between 35 and 65 times higher expression than B and C in CA from penultimate nymphal instar and adult females. RNAi-triggered knock down of BgJHAMT produces a dramatic reduction of JH synthesis, concomitant with a decrease of fat body viteUogenin expression and basal follicle length. BgJHAMT mRNA levels in CA of females along the gonadotrophic cycle parallel, with a slight advancement, JH synthesis profile. BgJHAMT mRNA levels were reduced in starved females and in females in which we reduced nutritional signaling by knocking down insulin receptor and target of rapamycin （TOR）. Results show that conditions that modify JH synthesis in adult B. germanica females show parallel changes of BgJHAMT mRNA levels and that the JH-specifie branch of the JH synthesis pathway is regulated in the same way as the mevalonate branch. Furthermore, we demonstrate that nutrition and its signaling through the insulin receptor and TOR pathways are essential for activating BgJHAMT expression, which suggests that this enzyme can be a checkpoint for the regulation of JH production in relation to nutritional status.