Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing 400716, China.
Int J Mol Sci. 2013 Aug 19;14(8):17055-72. doi: 10.3390/ijms140817055.
Chitin synthase (CHS), a potential target for eco-friendly insecticides, plays an essential role in chitin formation in insects. In this study, a full-length cDNA encoding chitin synthase 2 (BdCHS2) was cloned and characterized in the oriental fruit fly, Bactrocera dorsalis. The BdCHS2 cDNA had 4417 nucleotides, containing an open reading frame of 4122 nucleotides, which encoded 1373 amino acid residues with a predicted molecular weight of 158.5 kDa. Phylogenetic analysis with other insect CHSs suggested that BdCHS2 belongs to insect CHS2. The BdCHS2 transcript was predominately found in midgut but was detected at low levels in fat body, Malpighian tubules, integument, and trachea. Moreover, BdCHS2 was expressed in all developmental stages, and highly expressed in the feeding stages. There was a positive relationship between BdCHS2 expression and total chitin content during development. Furthermore, both the gene expression and chitin content in midgut decreased when the insect was fed for 24 h, then starved for 24 h, while they increased dramatically and rapidly under the condition of starvation for 24 h then feeding for 24 h. These results suggest that BdCHS2 may play an important role in regulating chitin content of the midgut, and subsequently affect the growth and development of B. dorsalis.
几丁质合成酶（CHS）是一种有潜力的环保型杀虫剂作用靶标，在昆虫的几丁质形成中发挥着重要作用。本研究克隆并鉴定了东方果实蝇 Bactrocera dorsalis 全长编码几丁质合成酶 2（BdCHS2）的 cDNA。BdCHS2 cDNA 长 4417 个核苷酸，包含一个长为 4122 个核苷酸的开放阅读框，编码 1373 个氨基酸残基，预测分子量为 158.5 kDa。与其他昆虫 CHSs 的系统发育分析表明，BdCHS2 属于昆虫 CHS2。BdCHS2 转录本主要在中肠中表达，但在脂肪体、马氏管、表皮和气管中也有低水平表达。此外，BdCHS2 在所有发育阶段都有表达，在取食阶段表达量较高。在发育过程中，BdCHS2 表达与总几丁质含量之间存在正相关关系。此外，当昆虫取食 24 h 后饥饿 24 h 时，中肠的基因表达和几丁质含量均下降，而饥饿 24 h 后取食 24 h 时，其表达和含量则迅速显著增加。这些结果表明，BdCHS2 可能在调节中肠几丁质含量方面发挥着重要作用，进而影响 B. dorsalis 的生长发育。
