Figure 8. A proposed model for locust Vg synthesis regulated by the JH-receptor complex acting on Mcm4 and Mcm7.

An active JH-receptor complex comprised of Met and SRC in the presence of JH induces the transcription of Mcm4 and Mcm7 to replicate the whole genome of fat body cells. The increased ploidy leads to multiple copies of Vg as well as genes coding for transcription factors and other regulatory proteins that directly or indirectly regulate Vg expression. These together ensure the massive synthesis of Vg and possibly other proteins for oocyte maturation and female fertility.