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Cited by 189Neurobiology and Insect Physiology ResearchSilkworms and Sericulture ResearchDevelopmental Biology and Gene Regulation

Knockout silkworms reveal a dispensable role for juvenile hormones in holometabolous life cycle

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Daimon, Takaaki, Uchibori, Miwa, Nakao, Hajime, Sezutsu, Hideki, Shinoda, Tetsuro·2015·Proceedings of the National Academy of Sciences
DOI 10.1073/pnas.1506645112PMC PMC4534237
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Abstract

Significance: The juvenile–adult transition is a key developmental process in organisms. A long-held paradigm in insect endocrinology is that juvenile hormones (JHs) prevent metamorphosis until larvae attain an appropriate size for the juvenile–adult transition. However, little is known about the roles for JHs during embryonic and very early larval stages. We established knockouts of the silkworm, a classic model insect, and show that embryogenesis and maintenance of juvenile status during the early larval stages are largely independent of JHs or the JH-signaling pathway. Our results also suggest that an unidentified factor or signal is required to acquire the competence for metamorphosis. The presence of this factor has long been overlooked because JHs may conceal its action.

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  • Later larval molts use JH via Kr-h1 to maintain larval molting and suppress E93 expression until larvae cross a size threshold for metamorphosis.

    “but later ones use JH (via Kr-h1 ) to maintain larval molting and suppress E93 expression until larvae cross a size threshold for metamorphosis.”

    From Regulation of metamorphosis in holometabolous insects (2026) · cites this paper as [12]

    The introduction says JH’s antimetamorphic action is needed in later larval stages until larvae reach an appropriate size, and the Gene-Expression Analysis shows that JH signaling induces Kr-h1. The paper does not show that this pathway suppresses E93 expression; its analysis of metamorphic gene expression focuses on broad instead. Page numbers were not available in the supplied passages. (LLM, conf=0.87)

    Experimental — accuracy not yet measured

  • A competence factor causes the juvenile to become JH-sensitive, and JH is thereafter required to maintain the juvenile condition.

    “A competence factor causes the juvenile to become JH-sensitive, and JH is thereafter required to maintain the juvenile condition (e.g. [12,51]).”

    From Regulation of metamorphosis in holometabolous insects (2026) · cites this paper as [12]

    The Development of JH-Deficient Mutants section reports that JH-deficient silkworms maintained larval status in the first two instars but could metamorphose precociously after the third, supporting a later role for JH in maintaining that status. The Significance and Discussion sections propose an unidentified competence factor for metamorphosis; they do not establish that it causes juveniles to become JH-sensitive. Page numbers are unavailable in our copy. (LLM, conf=0.86)

    Experimental — accuracy not yet measured

  • Early larval molts are JH-independent.

    “Early larval molts are JHindependent, but later ones use JH (via Kr-h1 ) to maintain larval molting and suppress E93 expression until larvae cross a size threshold for metamorphosis.”

    From Regulation of metamorphosis in holometabolous insects (2026) · cites this paper as [12]

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Research works printed but not linked: 50

  1. Riddiford LM (1996) Juvenile hormone: The status of its "status quo" action. Arch Insect Biochem Physiol 32(3-4):271-286.
  2. Riddiford LM (2012) How does juvenile hormone control insect metamorphosis and reproduction? Gen Comp Endocrinol 179(3):477-484.
  3. Niwa R, Niwa YS (2014) Enzymes for ecdysteroid biosynthesis: Their biological func- tions in insects and beyond. Biosci Biotechnol Biochem 78(8):1283-1292.
  4. Daimon T, Shinoda T (2013) Function, diversity, and application of insect juvenile hormone epoxidases (CYP15). Biotechnol Appl Biochem 60(1):82-91.
  5. Smykal V, et al. (2014) Importance of juvenile hormone signaling arises with com- petence of insect larvae to metamorphose. Dev Biol 390(2):221-230.
  6. Daimon T, et al. (2012) Precocious metamorphosis in the juvenile hormone-deficient mutant of the silkworm, Bombyx mori. PLoS Genet 8(3):e1002486.
  7. Tan A, Tanaka H, Tamura T, Shiotsuki T (2005) Precocious metamorphosis in trans- genic silkworms overexpressing juvenile hormone esterase. Proc Natl Acad Sci USA 102(33):11751-11756.
  8. Abdou MA, et al. (2011) Drosophila Met and Gce are partially redundant in trans- ducing juvenile hormone action. Insect Biochem Mol Biol 41(12):938-945.
  9. Riddiford LM, Truman JW, Mirth CK, Shen YC (2010) A role for juvenile hormone in the prepupal development of Drosophila melanogaster. Development 137(7):1117-1126.
  10. Aboulafia-Baginsky N, Pener MP, Staal GB (1984) Chemical allatectomy of late Locusta embryos by a synthetic precocene and its effect on hopper morphogenesis. J Insect Physiol 30(11):839-852.
  11. Furuta K, et al. (2007) Synthesis and anti-juvenile hormone activity of ethyl 4-(2- benzylalkyloxy)benzoates and their enantiomers. J Pestic Sci 32(2):99-105.
  12. Kayukawa T, et al. (2012) Transcriptional regulation of juvenile hormone-mediated induction of Krüppel homolog 1, a repressor of insect metamorphosis. Proc Natl Acad Sci USA 109(29):11729-11734.
  13. Daimon T, Kiuchi T, Takasu Y (2014) Recent progress in genome engineering techniques in the silkworm, Bombyx mori. Dev Growth Differ 56(1):14-25.
  14. Takasu Y, et al. (2013) Efficient TALEN construction for Bombyx mori gene targeting. PLoS One 8(9):e73458.
  15. Shinoda T, Itoyama K (2003) Juvenile hormone acid methyltransferase: A key regulatory enzyme for insect metamorphosis. Proc Natl Acad Sci USA 100(21):11986-11991.
  16. Zhou X, Riddiford LM (2002) Broad specifies pupal development and mediates the 'status quo' action of juvenile hormone on the pupal-adult transformation in Dro- sophila and Manduca. Development 129(9):2259-2269.
  17. Muramatsu D, Kinjoh T, Shinoda T, Hiruma K (2008) The role of 20-hydroxyecdysone and juvenile hormone in pupal commitment of the epidermis of the silkworm, Bombyx mori. Mech Dev 125(5-6):411-420.
  18. Zhou B, Hiruma K, Shinoda T, Riddiford LM (1998) Juvenile hormone prevents ecdysteroid-induced expression of broad complex RNAs in the epidermis of the to- bacco hornworm, Manduca sexta. Dev Biol 203(2):233-244.
  19. Reza AM, et al. (2004) Hormonal control of a metamorphosis-specific transcriptional factor Broad-Complex in silkworm. Comp Biochem Physiol B Biochem Mol Biol 139(4): 753-761.
  20. Baumann A, Fujiwara Y, Wilson TG (2010) Evolutionary divergence of the paralogs Methoprene tolerant (Met) and germ cell expressed (gce) within the genus Dro- sophila. J Insect Physiol 56(10):1445-1455.
  21. Jindra M, et al. (2015) Genetic evidence for function of the bHLH-PAS Protein Gce/Met as a Juvenile hormone receptor. PLoS Genet 11(7):e1005394.
  22. Oota S, Watanabe A, Tokunaga H (1956) Genetical study on a spontaneous mutant, two molter, in the silkworm, Bombyx mori. J Insect Biotec Seric 26(1):77-81.
  23. Riddiford LM, Williams CM (1967) The effects of juvenile hormone analogues on the embryonic development of silkworms. Proc Natl Acad Sci USA 57(3):595-601.
  24. Bergot BJ, Baker FC, Cerf DC, Jamieson G, Schooley DA (1981) Qualitative and quantitative aspects of juvenile hormone titers in developing embryos of several in- sect species: Discovery of a new JH-like substance extracted from eggs of Manduca sexta. Juvenile Hormone Biochemistry, eds Pratt GE, Brooks GT (Elsevier, Amsterdam), pp 33-45.
  25. Truman JW, Riddiford LM (1999) The origins of insect metamorphosis. Nature 401(6752):447-452.
  26. Sauman I, Reppert SM (1998) Brain control of embryonic circadian rhythms in the silkmoth Antheraea pernyi. Neuron 20(4):741-748.
  27. Sauman I, Tsai T, Roca AL, Reppert SM (1996) Period protein is necessary for circadian control of egg hatching behavior in the silkmoth Antheraea pernyi. Neuron 17(5): 901-909.
  28. Fujii T, Abe H, Yamamoto K, Katsuma S, Shimada T (2011) Interspecies linkage analysis of mo, a Bombyx mori locus associated with mosaicism and gynandromorphism. Genetica 139(10):1323-1329.
  29. Fristrom D, Fristrom JW (1993) The metamorphic development of the adult epidermis. The Development of Drosophila melanogaster, eds Bate M, Arias AM (Cold Spring Harbor Lab Press, Plainview, NY), pp 843-897.
  30. Konopova B, Jindra M (2007) Juvenile hormone resistance gene Methoprene-tolerant controls entry into metamorphosis in the beetle Tribolium castaneum. Proc Natl Acad Sci USA 104(25):10488-10493.
  31. Minakuchi C, Namiki T, Shinoda T (2009) Krüppel homolog 1, an early juvenile hor- mone-response gene downstream of Methoprene-tolerant, mediates its anti-meta- morphic action in the red flour beetle Tribolium castaneum. Dev Biol 325(2):341-350.
  32. Uhlirova M, et al. (2003) Use of Sindbis virus-mediated RNA interference to demon- strate a conserved role of Broad-Complex in insect metamorphosis. Proc Natl Acad Sci USA 100(26):15607-15612.
  33. Konopova B, Jindra M (2008) Broad-Complex acts downstream of Met in juvenile hormone signaling to coordinate primitive holometabolan metamorphosis. Devel- opment 135(3):559-568.
  34. Parthasarathy R, Tan A, Bai H, Palli SR (2008) Transcription factor broad suppresses precocious development of adult structures during larval-pupal metamorphosis in the red flour beetle, Tribolium castaneum. Mech Dev 125(3-4):299-313.
  35. Suzuki Y, Truman JW, Riddiford LM (2008) The role of Broad in the development of Tribolium castaneum: Implications for the evolution of the holometabolous insect pupa. Development 135(3):569-577.
  36. Zhou B, Riddiford LM (2001) Hormonal regulation and patterning of the broad- complex in the epidermis and wing discs of the tobacco hornworm, Manduca sexta. Dev Biol 231(1):125-137.
  37. Erezyilmaz DF, Riddiford LM, Truman JW (2004) Juvenile hormone acts at embryonic molts and induces the nymphal cuticle in the direct-developing cricket. Dev Genes Evol 214(7):313-323.
  38. Rohdendorf EB, Sehnal F (1973) Inhibition of reproduction and embryogenesis in the fireblat, Thermobia domestica, by juvenile hormone analogues. J Insect Physiol 19(1): 37-56.
  39. Quan GX, et al. (2002) Characterization of the kynurenine 3-monooxygenase gene corresponding to the white egg 1 mutant in the silkworm Bombyx mori. Mol Genet Genomics 267(1):1-9.
  40. McRobert SP, et al. (2003) Mutations in raised Drosophila melanogaster affect ex- perience-dependent aspects of sexual behavior in both sexes. Behav Genet 33(3): 347-356.
  41. Kayukawa T, Shinoda T (May 7, 2015) Functional characterization of two paralogous JH receptors, methoprene-tolerant 1 and 2, in the silkworm, Bombyx mori (Lepidoptera: Bombycidae). Appl Entomol Zool, 10.1007/s13355-015-0345-8. · DOI
  42. Ureña E, Manjón C, Franch-Marro X, Martín D (2014) Transcription factor E93 specifies adult metamorphosis in hemimetabolous and holometabolous insects. Proc Natl Acad Sci USA 111(19):7024-7029.
  43. Williams CM (1961) The juvenile hormone. II. Its role in the endocrine control of molting, pupation, and adult development in the cecropia silkworm. Biol Bull 121(3): 572-585.
  44. Parthasarathy R, Tan A, Palli SR (2008) bHLH-PAS family transcription factor metho- prene-tolerant plays a key role in JH action in preventing the premature development of adult structures during larval-pupal metamorphosis. Mech Dev 125(7):601-616.
  45. Goodman WG, Cusson M (2012) The juvenile hormones. Insect Endocrinology, ed Gilbert LI (Elsevier, London), pp 311-365.
  46. Nijhout HF (1998) Insect Hormones (Princeton Univ Press, Princeton, NJ).
  47. Daimon T, et al. (2003) A Bombyx mori gene, BmChi-h, encodes a protein homologous to bacterial and baculovirus chitinases. Insect Biochem Mol Biol 33(8):749-759.
  48. Tamura T, et al. (2000) Germline transformation of the silkworm Bombyx mori L. using a piggyBac transposon-derived vector. Nat Biotechnol 18(1):81-84.
  49. Nakao H, Matsumoto T, Oba Y, Niimi T, Yaginuma T (2008) Germ cell specification and early embryonic patterning in Bombyx mori as revealed by nanos orthologues. Evol Dev 10(5):546-554.
  50. Kayukawa T, et al. (2014) Hormonal regulation and developmental role of Krüppel homolog 1, a repressor of metamorphosis, in the silkworm Bombyx mori. Dev Biol 388(1):48-56.

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Authors
Daimon, T., Uchibori, M., Nakao, H., Sezutsu, H., & Shinoda, T.
Affiliations
  • Institute of Agrobiological Sciences (JP)
  • Division of Insect Sciences, National Institute of Agrobiological Sciences, Owashi 1-2, Tsukuba City, Ibaraki, 305-8634, Japan;
ORCID
Venue
Proceedings of the National Academy of Sciences
Publisher
National Academy of Sciences
Published
2015-07-20
Volume
112
Issue
31
Pages
E4226-35
ISSN
  • 0027-8424 (ISSN-L)
  • 1091-6490
DOI
10.1073/pnas.1506645112
PMC
PMC4534237
OpenAlex
W1834972362
Cited by
189
References
2
Citations by year
2026: 21 · 2025: 30 · 2024: 30 · 2023: 20 · 2022: 18 · 2021: 10 · 2020: 15 · 2019: 14 · 2018: 9 · 2017: 12 · 2016: 8 · 2015: 2
FWCI
4.82
Type
journal article
Language
en
Open access
Licence
www.pnas.org/site/misc/userlicense.xhtml (vor, 184 d)
Locations
  • Proceedings of the National Academy of Sciences (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Funders
Ministry of Education, Culture, Sports, Science, and Technology (23688008, 25252059)
Topics
  • Life Sciences › Neuroscience › Cellular and Molecular Neuroscience › Neurobiology and Insect Physiology Research
  • Life Sciences › Agricultural and Biological Sciences › Insect Science › Silkworms and Sericulture Research
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Developmental Biology and Gene Regulation
Keywords
juvenile hormone, Bombyx mori, metamorphosis, precocious metamorphosis, larval competence, embryonic development, mosaic analysis, genome editing
MeSH terms
Alleles, Animals, Base Sequence, Crosses, Genetic, Embryo, Nonmammalian, Endonucleases, Female, Juvenile Hormones, Larva, Life Cycle Stages, Male, Molecular Sequence Data, Mosaicism, Mutation, Phenotype, Bombyx, Signal Transduction, Trans-Activators, Genes, Insect, Gene Targeting, Gene Expression Regulation, Developmental, Embryonic Development, Gene Knockout Techniques

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