关键词: 棉铃虫, 蜕皮, 同工酶, 表达模式, 分子靶标

Abstract: Isozymes exist in tissues and cells in various organisms. They express in specific patterns at different developmental stages and play important roles. Insect molting is a cascade controlled by prothoracicotropic hormone （PTTH）， 20-hydroxyecdysone and juvenile hormone. Isozymes are involved in this cascade. Demonstrating the expression patterns of the isozymes during molting may provide molecular targets for investigating the molecular mechanism of molting. The isozymes also offer targets to detect the efficacy of new molting regulatory insecticides. We investigated the expression patterns of the peroxidases, alcohol dehydrogenases and esterases in molting larvae of the cotton bollworm, H. armigera. The results indicated that the expression of three peroxidases, two alcohol dehydrogenases and three esterases was involved in the molting or metamorphosis process. The non-steroidal ecdysone agonist RH-2485 could induce the expression of one of the esterases, which might be involved in the molting process. N-terminal amino acid sequence from one of the esterases was determined. These findings provided new molecular targets for studying the mechanisms of insect molting and assaying the efficacy of new moltinginduced regulatory insecticides.

Key words: Helicoverpa armigera, molting, isozyme, expression pattern, molecular target