title: Expression and functions of dopa decarboxylase in the silkworm, Bombyx mori was regulated by molting hormone.
abstract: Insect molting is an important developmental process of metamorphosis, which is initiated by molting hormone. Molting includes the activation of dermal cells, epidermal cells separation, molting fluid secretion, the formation of new epidermis and old epidermis shed and other series of continuous processes. Polyphenol oxidases, dopa decarboxylase and acetyltransferase are necessary enzymes for this process. Traditionally, the dopa decarboxylase (BmDdc) was considered as an enzyme for epidermal layer's tanning and melanization. This work suggested that dopa decarboxylase is one set of the key enzymes in molting, which closely related with the regulation of ecdysone at the time of biological molting processes. The data showed that the expression peak of dopa decarboxylase in silkworm is higher during molting stage, and decreases after molting. The significant increase in the ecdysone levels of haemolymph was also observed in the artificially fed silkworm larvae with ecdysone hormone. Consistently, the dopa decarboxylase expression was significantly elevated compared to the control. BmDdc RNAi induced dopa decarboxylase expression obviously declined in the silkworm larvae, and caused the pupae appeared no pupation or incomplete pupation. BmDdc was mainly expressed and stored in the peripheral plasma area near the nucleus in BmN cells. In larval, BmDdc was mainly located in the brain and epidermis, which is consisted with its function in sclerotization and melanization. Overall, the results described that the dopa decarboxylase expression is regulated by the molting hormone, and is a necessary enzyme for the silkworm molting.
authors: Key Laboratory of Animal Virology of Ministry of Agriculture, College of Animal Sciences, Zhejiang University, Hangzhou, 310058, People's Republic of China.
authors: Mei-xian
authors: MX
authors: Wang
authors: Zi-zheng
authors: ZZ
authors: Cai
authors: Yan
authors: Y
authors: Lu
authors: Hu-Hu
authors: HH
authors: Xin
authors: Rui-ting
authors: RT
authors: Chen
authors: Shuang
authors: S
authors: Liang
authors: Chabungbam Orville
authors: CO
authors: Singh
authors: Jong-Nam
authors: JN
authors: Kim
authors: Yan-shan
authors: YS
authors: Niu
authors: Yun-gen
authors: YG
authors: Miao
mesh_terms: D000818:Animals; D015153:Blotting, Western; D012831:Bombyx / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D004296:Dopa Decarboxylase / Q000235:genetics* / Q000378:metabolism; D004440:Ecdysone / Q000008:administration & dosage / Q000494:pharmacology*; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D007814:Larva / Q000187:drug effects / Q000235:genetics; D009928:Organ Specificity / Q000187:drug effects / Q000235:genetics; D021381:Protein Transport / Q000187:drug effects; D012330:RNA, Double-Stranded / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
chemical_list: D012330:RNA, Double-Stranded; D012333:RNA, Messenger; D004440:Ecdysone; D004296:Dopa Decarboxylase
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