CUTICULAR PROTEIN GENES IN TENEBRIO-MOLITOR (COLEOPTERA, TENEBRIONIDAE)

We have previously isolated from the beetle Tenebrio molitor, cDNAs co ding for two glycine-rich cuticular proteins named ACP-20, ACP-22 and ACP-17 and an alanin-rich cuticular protein named LPCP-22. The ACP-20, ACP-22, ACP-17 mRNAs are detected by Northern blot and in situ hybrid ization analysis only in epidermal regions secreting heavily sclerotiz ed cuticle during the pharate adult stage. The LPCP-22 mRNA is detecte d in most epidermal regions during the secretion of larval and pupal c uticles. Then, its presence is restricted to the epidermal zones secre ting intersegmental soft cuticle in the newly ecdysed pupa. This stage - and tissue-specific gene system seems to be a convenient model for s tudying the regulation of sequential gene expression by ecdysteroids a nd juvenile hormone.