Abstract
Synthesis and accumulation of protein in the ovaries of Bombyx mori were analyzed by means of in vitro incorporation of 14C-amino acids and electrophoresis. The incorporation of 14C-amino acids into the normal ovaries was most active during the middle stages of pupal life. Along with the increase in synthetic activities, there was an increase in the protein content as well as number of protein bands on gel electrophoresis. In ovaries of the smn mutant, incorporative activities of radioactive amino acids remained at a low level throughout the pupal development, and ovarian protein content showed no increase. While vitellogenin in haemolymph was incorporated actively into the normal ovaries and deposited into egg chambers, smn ovaries were unable to incorporate vitellogenin from haemolymph into oocytes. Hence, enormous quantities of vitellogenin were retained in the haemolymph of the smn female moth. These results suggest that the smn gene may affect the ovaries in the process of protein synthesis and uptake and accumulation of vitellogenic protein from haemolymph.
