Insect juvenile hormones (JHs) ensure growth of the larva, while preventing metamorphosis, and they are important for egg production in female insects. Peptidic juvenoids known from 1970s act as other JH synthetic mimics, some of which serve as insecticides, but stand out as being highly potent yet exquisitely selective to a specific family of true bugs. Unfortunately, these molecules stayed abandoned, as their mode of action was never explained.
The scientists from the Biology Center, the Institute of Molecular Genetics, the University of South Bohemia, and Pavel Majer Group from IOCB Prague showed that peptidic juvenoids act through the canonical JH receptor complex of the linden bug, Pyrrhocoris apterus. The juvenoids induced ligand-dependent dimerization between Met and Tai proteins from P. apterus but, consistent with their selectivity, not from other insects.
To explore the potential of juvenoid peptides, the researchers synthesized 120 new derivatives and tested them in Met–Tai interaction assays. Some of the newly synthesized peptidic derivatives outperform established JH mimics by two orders of magnitude while retaining their target species selectivity. The study also proposes an advanced structural model for interaction of highly potent juvenoids with the JH receptor. The peptidic juvenoids behave as agents for precisely targeted and sustainable insect control.
Original article: Tumova, S.; Milacek, M.; Šnajdr, I.; Muthu, M.; Tuma, R.; Reha, D.; Jedlicka, P.; Bittova, L.; Novotna, A.; Majer, P.; Sedlak, D.; Jindra, M. Unique peptidic agonists of a juvenile hormone receptor with species-specific effects on insect development and reproduction. Proc. Natl. Acad. Sci. U.S.A. 2022, 119, 48, e2215541119. https://doi.org/10.1073/pnas.2215541119
