Liu J, Shi G-P, Zhang W-Q, Zhang G-R, Xu W-H
Department of Molecular and Cell Biology, University of Science and Technology of China, Hefei, China.
Insect Mol Biol. 2006 Dec;15(6):823-34. doi: 10.1111/j.1365-2583.2006.00686.x.
Moulting is an essential process of insect development but little is known about cysteine proteases in the process. Here, we detail a proteolytic activity profile from fifth larval instar to new pupae of the lepidopteran Helicoverpa armigera. At fifth to sixth instar moulting, the activities were significantly higher than those in non-moulting stages, and were inhibited by the cysteine protease inhibitor, 2S, 3S-trans-epoxysuccinyl-L-leucylamido-3-methylbutane ethyl ester (E-64), or by the cathepsin L-selective inhibitor CLIK148. Further, a 1513 bp cathepsin L cDNA (Har-CL) was isolated from the H. armigera larval cuticle and epidermis layer. Har-CL gene expression, which is correlated closely with ecdysone, was higher during larval moulting. Injection of E-64 or CLIK148 resulted in delayed fifth to sixth instar moulting, suggesting an essential role for cathepsin L in larval moulting.
蜕皮是昆虫发育的一个重要过程，但在此过程中对半胱氨酸蛋白酶却知之甚少。在此，我们详细描述了鳞翅目棉铃虫从五龄幼虫到新蛹期的蛋白水解活性概况。在五龄到六龄蜕皮时，其活性显著高于非蜕皮阶段，并且受到半胱氨酸蛋白酶抑制剂2S，3S-反式环氧琥珀酰-L-亮氨酰胺-3-甲基丁烷乙酯（E-64）或组织蛋白酶L选择性抑制剂CLIK148的抑制。此外，从棉铃虫幼虫的表皮和真皮层中分离出一个1513 bp的组织蛋白酶L cDNA（Har-CL）。与蜕皮激素密切相关的Har-CL基因表达在幼虫蜕皮期间较高。注射E-64或CLIK148会导致五龄到六龄蜕皮延迟，这表明组织蛋白酶L在幼虫蜕皮中起重要作用。
