title: A biological timer in the fat body comprising Blimp-1, βFtz-f1 and Shade regulates pupation timing in Drosophila melanogaster.
abstract: During the development of multicellular organisms, many events occur with precise timing. In Drosophila melanogaster, pupation occurs about 12 h after puparium formation and its timing is believed to be determined by the release of a steroid hormone, ecdysone (E), from the prothoracic gland. Here, we demonstrate that the ecdysone-20-monooxygenase Shade determines pupation timing by converting E to 20-hydroxyecdysone (20E) in the fat body, which is the organ that senses nutritional status. The timing of shade expression is determined by its transcriptional activator βFtz-f1. The βftz-f1 gene is activated after a decline in the expression of its transcriptional repressor Blimp-1, which is temporally expressed around puparium formation in response to a high titer of 20E. The expression level and stability of Blimp-1 is critical for the precise timing of pupation. Thus, we propose that Blimp-1 molecules function like sand in an hourglass in this precise developmental timer system. Furthermore, our data suggest that a biological advantage results from both the use of a transcriptional repressor for time determination and the association of developmental timing with nutritional status of the organism.
authors.affiliation: The Graduate School of Natural Science and Technology, Okayama University, Okayama, Okayama 700-8530, Japan.
authors.forename: Kazutaka
authors.identifier: 0000-0001-7694-425X
authors.initials: K
authors.lastname: Akagi
authors.affiliation: The Graduate School of Natural Science and Technology, Okayama University, Okayama, Okayama 700-8530, Japan.
authors.forename: Moustafa
authors.identifier: 0000-0003-0698-8438
authors.initials: M
authors.lastname: Sarhan
authors.affiliation: The Graduate School of Natural Science and Technology, Okayama University, Okayama, Okayama 700-8530, Japan.
authors.forename: Abdel-Rahman S
authors.initials: AR
authors.lastname: Sultan
authors.affiliation: The Graduate School of Natural Science and Technology, Okayama University, Okayama, Okayama 700-8530, Japan.
authors.forename: Haruka
authors.initials: H
authors.lastname: Nishida
authors.affiliation: The Graduate School of Natural Science and Technology, Okayama University, Okayama, Okayama 700-8530, Japan.
authors.forename: Azusa
authors.initials: A
authors.lastname: Koie
authors.affiliation: The Graduate School of Natural Science and Technology, Okayama University, Okayama, Okayama 700-8530, Japan.
authors.forename: Takumi
authors.initials: T
authors.lastname: Nakayama
authors.affiliation: The Graduate School of Natural Science and Technology, Okayama University, Okayama, Okayama 700-8530, Japan Department of Biology, Faculty of Science, Okayama University, Okayama, Okayama 700-8530, Japan hueda@cc.okayama-u.ac.jp.
authors.forename: Hitoshi
authors.identifier: 0000-0002-1624-4101
authors.initials: H
authors.lastname: Ueda
mesh_terms: D000818:Animals; D001683:Biological Clocks / Q000187:drug effects; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D029721:Drosophila Proteins / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000187:drug effects / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D004441:Ecdysterone / Q000494:pharmacology; D005216:Fat Body / Q000187:drug effects / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D008954:Models, Biological; D055550:Protein Stability / Q000187:drug effects; D011679:Pupa / Q000235:genetics / Q000254:growth & development*; D011987:Receptors, Steroid / Q000378:metabolism*; D012097:Repressor Proteins / Q000378:metabolism*; D013997:Time Factors
chemical_list: C525044:Blimp-1 protein, Drosophila; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D011987:Receptors, Steroid; D012097:Repressor Proteins; C080885:nuclear hormone receptor FTZ-F1 beta, Drosophila; D004441:Ecdysterone; D003577:Cytochrome P-450 Enzyme System
keywords: Biological timer; Developmental timing; Drosophila; Ecdysone; Metamorphosis