Abstract: Chitin is an important content in the exoskeletons of arthropods, and its hydrolyzation is catalyzed by chitinases during the process of molting, thus, the chitinases are considered as ideal target to interfere the growth of arthropods.  This study intends to clarify the characteristic of the chitinases during the development of Tetranychus cinnabarinus, and screen out important genes as potential control targets.  The results showed that the total enzyme concentration of chitinases was significantly higher in larva, the first and second nymph than that in egg and adult.  Base on the transcriptome data, six unigenes encoding chitinases were identified and their expression patterns in different developmental stages were detected. The expressions of TcCHIT1 and TcCHIT10 showed high abundance during the molting process and their expression change during the developmental stages was consistent with the enzyme concentration.  The full-length of these two genes were further cloned, and the structural characteristics of their proteins were analyzed by constructing the three-dimensional structure model.  The results provide basic information to understand the characteristic of chitinases in T. cinnabarinus and might be considered as target for control.

Key words: Tetranychus cinnabarinus, chitinase, gene expression, protein structure