RNA content and RNA synthesis in diapause and non-diapause eggs of Bombyx mori

Abstract

Changes in amount of RNA and its synthesis were studied in diapause and non-diapause eggs of Bombyx mori. In non-diapause eggs, the amount of total RNA began to increase at the stage of late gastrula and increased constantly thereafter. The synthesis of total and ribosomal RNA commenced at the onset of gastrulation, and after two days it levelled off. In contrast, the amount of total RNA in diapause eggs did not change essentially, and only a low level of total and ribosomal RNA synthesis was detected. On the other hand, if diapause eggs were activated by hot HCl treatment 24 hr after oviposition, the results obtained were essentially similar to those for non-diapause eggs, except that there was a lag of two days after acid treatment. These findings indicate that a significant control of ribosomal and other RNA occurs in relation to diapause and development.