Abstract
Our understanding of JH biosynthesis has significantly changed in the last years. In this review I would like to discuss the following topics: (1) the progresses in understanding the JH biosynthesis pathway. Access to genome sequences has facilitated the identification of all the genes encoding biosynthetic enzymes and the completion of comprehensive transcriptional studies, as well as the expression and characterization of recombinant enzymes. Now the existence of different flux directionalites, feed-back loops and pathway branching points in the JH biosynthesis pathways can be explored; (2) the new concepts in the modulation of JH synthesis by allatoregulators. The list of putative JH modulators is increasing. I will discuss their possible role during the different physiological states of the CA; (3) the new theoretical and physiological frameworks for JH synthesis analysis. I will discuss the bases of the flux model for JH biosynthesis. JH plays multiple roles in the control of ovary development in female mosquitoes; therefore, the CA presents different physiological states, where JH synthesis is altered by gating the flux at distinctive points in the pathway; (4) in the final section I will identify new challenges and future directions on JH synthesis research.
Highlights
Juvenile hormone (JH) regulates development and reproductive maturation in insects [1, 2]; interruption of JH biosynthesis has been considered as a strategy for the development of target-specific insecticides [3]
We have previously described that transcript levels for most of the JH biosynthetic enzymes are very low in early pupae [6]; JH synthesis rates were undetectable in pupae 24 and 12 h before adult eclosion
A potential role of the CC on corpora allata gland (CA) regulation has been proposed in B. mori [108, 109]; separation of the CA from the CC often results in increases of JH synthesis in vitro in A. aegypti [93]
Summary
Juvenile hormone (JH) regulates development and reproductive maturation in insects [1, 2]; interruption of JH biosynthesis has been considered as a strategy for the development of target-specific insecticides [3]. Recent studies in the heteropteran linden bug, Pyrrhocoris apterus, indicate that JH stimulates oogenesis through Met and Taiman but regulates gene expression in the gut through interactions of Met with the circadian proteins Clock and Cycle [52]; the latter bHLH-PAS protein has been shown to bind Met in a JH-dependent manner [53]. More answers to these questions are sure to be provided in the few years
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
