Role of in the Molting and Metamorphosis of the Cigarette Beetle .

Chitin deacetylases (CDAs) are chitin-modifying enzymes known to play vital roles in insect metamorphosis and development. In this study, we identified and characterized a gene () from the cigarette beetle . contains a 1614 bp open reading frame encoding a protein of 537 amino acids that includes domain structures typical of CDAs. was mainly expressed in the late larval and late pupal stages. In larval tissues, the highest level of was detected in the integument. The expression of was induced by 20-hydroxyecdysone (20E) in vivo, and it was significantly suppressed by knocking down the expression of ecdysteroidogenesis genes and 20E signaling genes. RNA interference (RNAi)-aided silencing of in fifth-instar larvae prevented the larval-pupal molt and caused 75% larval mortality. In the late pupal stage, depletion of resulted in the inhibition of pupal growth and wing abnormalities, and the expression levels of four wing development-related genes (DY, , , and ) were dramatically decreased. Meanwhile, the chitin contents of RNAi beetles were significantly reduced, and expressions of three chitin synthesis pathway genes (, , and ) were greatly decreased. The results suggest that is indispensable for larval-pupal and pupal-adult molts, and that it is a potential target for the RNAi-based control of .