Insect cuticle consists of numerous structural proteins, which could interact with polysaccharide, chitin, and alter properly mechanical property of the cuticle. Cuticular Protein Analogous to Peritrophins (CPAPs) are characterized by presence of one (CPAP1s) or three (CPAP3s) chitin-binding domain belong to CBM14/ChtBD2 family. In this study, we investigated physiological functions of TcCPAP1-H and TcCPAP3-C in Tribolium castaneum. RNAi for either TcCPAP1-H or TcCPAP3-C at late instar larvae had no effect on larval-pupal molt nor pupal development. However, the resulting pharate adults failed to shed their old pupal cuticle and died entrapped in it without undergoing eclosion. TEM analysis, in addition, revealed disorganized chitinous horizontal laminae and/or vertical pore canals of rigid cuticle from TcCPAP1-H- and TcCPAP3-C-deficient adults. Desiccation-induced death produced by injection of dsTcCPAP1-H into young instar larvae is also discussed.

• Myeongjin Kim(Department of Applied Biology, Chonnam National University)
• Seulgi Mun(Department of Applied Biology, Chonnam National University)
• Mi Young Noh(Department of Forestry, Chonnam National University)
• Yasuyuki Arakane(Department of Applied Biology, Chonnam National University)