In 1987, Laufer and his colleagues first identified methyl farnesoate (MF) from the hemolymph of the spider crab Libinia emarginata as a juvenile hormone (JH)-like factor produced by the mandibular organs (MOs). Since then, MF has been found in more than 35 crustacean species.MF is also found in several insect species, and a species of mite.
MF is lipophilic, and highly soluble in hexane and ethanol.
MF has multiple physiological functions, including the regulation of metabolism, molting, reproduction, behavior, and morphogenesis in crustaceans.It stimulates general protein synthesis and ecdysteroid secretion by the Y-organ, and influences the molting cycle.MF plays a key role in the regulation of crustacean reproduction; it enhances egg production in females, and affects the reproductive morphology and behavior in males.The expression of the vitellogenin (Vg) gene is induced by MF in the hepatopancreas, although FA is more potent than MF for this activity.MF has either a stimulatory or an inhibitory role in metamorphosis, depending on the species and developmental stages.MF functions as a sex determinant and induces the production of male offspring in daphnids and other cladoceran species,and is also involved in predator-induced polyphenisms in Daphnia.
MF is synthesized by and secreted from the MOs of crustaceans. Like insect JH, MF is synthesized from acetyl-CoA through the mevalonate pathway and the MF-specific pathway.The farnesoic acid O-methyltransferase (FAMeT) gene has been considered as encoding the enzyme that catalyzes FA to MF in crustaceans.In contrast, in insects MF is synthesized from FA by an enzyme encoded in JHAMT, which belongs to a gene family distinct from FAMeT.Recently, JHAMT homologs were also found in the waterflea Daphnia pulex and a species of mite.Therefore, the relevance of FAMeT and JHAMT in MF synthesis in crustaceans and other arthropods needs to be reassessed.
ChEBI: A member of the juvenile hormone family of compounds that is the methyl ester of farnesoic acid. Found in several species of crustaceans.
