Advances in studies on insect juvenile hormone and vitellogenesis regulated by juvenile hormone

Juvenile hormones(JHs) is a group of acyclic sesquiterpenoids found in insects that is synthesized from the corpora allata(CA) through the mevalonate pathway and secreted to the hemolymph. It regulates many aspects of insect physiology, such as development, metamorphosis and reproduction. Among the various facets of JHs function, this review mainly focuses on the biosynthesis and metabolism of JHs and its physiological effects, especially on vitellogenesis.