(S)-(+)-Methoprene is a widely-used insect growth regulator.¹It is remarkable for its lack of significant effects against a wide variety of mammals, although concerns remain for its effects on arthropod development.^1,2Methoprene acts as an activator of the juvenile hormone receptor, known as Methoprene-tolerant or Met (K_d= 12.3 nM).^3,4Met is a transcription factor that, upon activation with juvenile hormone or methoprene, regulates gene expression that inhibits metamorphosis.⁵

1.Siddall, J.B.Insect growth regulators and insect control: A critical appraisalEnvironmental Health Perspectives14119-126(1976) 2.Wright, J.E.Environmental and toxicological aspects of insect growth regulatorsEnvironmental Health Perspectives14127-132(1976) 3.Charles, J.P., Iwema, T., Epa, V.C., et al.Ligand-binding properties of a juvenile hormone receptor, methoprene-tolerantProceedings of the National Academy of Sciences of the United States of America108(52)21128-21133(2011) 4.Osir, E.O., and Riddiford, L.M.Nuclear binding sites for juvenile hormone and its analogs in the epidermis of the tobacco hornwormThe Journal of Biological Chemisty263(27)13812-13818(1988) 5.Zou, Z., Saha, T.T., Roy, S., et al.Juvenile hormone and its receptor, methoprene-tolerant, control the dynamics of mosquito gene expressionProceedings of the National Academy of Sciences of the United States of America110(24)E2173-E2181(2013)