ACCUMULATION OF BMSP1 MESSENGER-RNA IN IMAGINAL WING DISCS OF BOMBYX-MORI DURING INTERMOLTS

A cDNA clone corresponding to an mRNA which accumulated in the wing di sc of Bombyx mori has been characterized. The accumulation was restric ted to the feeding periods of the intermolts, and the mRNA rapidly dis appeared during the larval molt and the spinning period. This accumula tion was strongly inhibited by 20-hydroxyecdysone both in vivo and in vitro. The amino acid sequence predicted for the putative protein corr esponds to that of the Bombyx mori storage protein 1 (Sakurai et al., 1988). Using in situ hybridization, the mRNA was located in cells asso ciated with trachea formation. Significance of the presence of the mRN A of a storage protein in developing wing disc is discussed.