TcCPR27 and TcCPR18 are abundant in cuticle of the pronotum.

To suppress cuticle tanning, dsRNA for TcLac2 (2 ng per insect) was injected into day 0 pupae. Proteins from the pronotum and elytra were extracted from five adults at 0–30 min after eclosion, and the extracts were analyzed by SDS-PAGE (left panel). In the dsVer-treated control animals, the extent of tanning of the pronotum was substantially greater than that of the elytron (right panel). S: PBS homogenate supernatant, P: PBS homogenate pellet.