保幼激素生物合成研究进展

保幼激素（juvenile hormone，JH）是存在于昆虫、甲壳动物和部分植物体内的倍半萜类衍生物。在昆虫和甲壳动物体内，保幼激素主要调节变态和生殖活动。在植物体内，则可能作为异株克生物质发挥作用。保幼激素主要通过细胞质内的甲羟戊酸途径（MVA）合成，植物质体内存在萜类合成的1-去氧木糖-5-磷酸途径（DXP）。MVA和DXP途径通过单向质子协同运输系统进行协调，使DXP途径中形成的前体化合物参与MVA途径的倍半萜合成。JH生物合成的主要步骤己基本查明，但与合成相关的酶学研究还较薄弱。生物合成酶的分子生物学是近来研究的热点，相关酶的cDNA克隆已有报道。JH生物合成酶的进一步研究有助于查明JH生物合成调控机制，深化对节肢动物生殖的理解，还可为新型杀虫剂开发提供可能的靶标。

Advances in studies on juvenile hormone biosynthesis

Juvenile hormones(JHs) are a group of sesquiterpenoid derivatives found in insects, crutaceans and some plants. JHs regulate metamorphosis and reproduction in arthropods and may function as an allelopathic agent in the plants. JHs are mainly produced via the cytosolic pathway, which involves mevalonate (MVA) as a key intermediate. The plastidial pathway via 1-deoxy-xylulose 5-phosphate (DXP) has been described from plants. The cooperation of both pathways via a unidirectional proton symport system has been reported for the biosynthesis of certain sesquiterpenes in some plants. Although the biosynthetic pathway of JH has been elucidated, the enzymes related to the pathway are poorly understood. Recent studies have focused on molecular biology of JH biosynthetic enzymes. The cDNA of some enzymes related to JH biosynthesis have been cloned from crustaceans and insects. Further studies on the JH biosynthetic enzymes will help clarify the regulating mechanisms of JH biosynthesis and improve our understanding of the arthropod reproduction. Moreover, the studies will offer a potential target for the development of novel insect control agents.