Mello, T. R.P.Aleixo, A. C.Pinheiro, D. G. [UNESP]Nunes, F. M.F.Cristino, A. S.Bitondi, M. M.G.Barchuk, A. R.Simões, Z. L.P.2019-10-062019-10-062019-02-01Insect Molecular Biology, v. 28, n. 1, p. 145-159, 2019.1365-25830962-1075http://hdl.handle.net/11449/187011Ftz-f1 is an orphan member of the nuclear hormone receptor superfamily. A 20-hydroxyecdysone pulse allows ftz-f1 gene expression, which then regulates the activity of downstream genes involved in major developmental progression events. In honeybees, the expression of genes like vitellogenin (vg), prophenoloxidase and juvenile hormone-esterase during late pharate-adult development is known to be hormonally controlled in both queens and workers by increasing juvenile hormone (JH) titres in the presence of declining levels of ecdysteroids. Since Ftz-f1 is known for mediating intracellular JH signalling, we hypothesized that ftz-f1 could mediate JH action during the pharate-adult development of honeybees, thus controlling the expression of these genes. Here, we show that ftz-f1 has caste-specific transcription profiles during this developmental period, with a peak coinciding with the increase in JH titre, and that its expression is upregulated by JH and downregulated by ecdysteroids. RNAi-mediated knock down of ftz-f1 showed that the expression of genes essential for adult development (e.g. vg and cuticular genes) depends on ftz-f1 expression. Finally, a double-repressor hypothesis-inspired vg gene knock-down experiment suggests the existence of a positive molecular loop between JH, ftz-f1 and vg.145-159eng20-hydroxyecdysone20EFushi tarazu transcription factor 1honey beejuvenile hormoneRNAiArtigo10.1111/imb.12541Acesso restrito2-s2.0-85055683303