1
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Matsuda K, Adachi H, Gotoh H, Inoue Y, Kondo S. Adhesion and shrinkage transform the rounded pupal horn into an angular adult horn in Japanese rhinoceros beetle. Development 2024; 151:dev202082. [PMID: 38477641 DOI: 10.1242/dev.202082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 02/14/2024] [Indexed: 03/14/2024]
Abstract
Clarifying the mechanisms underlying shape alterations during insect metamorphosis is important for understanding exoskeletal morphogenesis. The large horn of the Japanese rhinoceros beetle Trypoxylus dichotomus is the result of drastic metamorphosis, wherein it appears as a rounded shape during pupation and then undergoes remodeling into an angular adult shape. However, the mechanical mechanisms underlying this remodeling process remain unknown. In this study, we investigated the remodeling mechanisms of the Japanese rhinoceros beetle horn by developing a physical simulation. We identified three factors contributing to remodeling by biological experiments - ventral adhesion, uneven shrinkage, and volume reduction - which were demonstrated to be crucial for transformation using a physical simulation. Furthermore, we corroborated our findings by applying the simulation to the mandibular remodeling of stag beetles. These results indicated that physical simulation applies to pupal remodeling in other beetles, and the morphogenic mechanism could explain various exoskeletal shapes.
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Affiliation(s)
- Keisuke Matsuda
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan
| | - Haruhiko Adachi
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata 997-0017, Japan
| | - Hiroki Gotoh
- Department of Biological Sciences, Faculty of Science, Shizuoka University, Shizuoka, Shizuoka 422-8529, Japan
| | - Yasuhiro Inoue
- Department of Micro Engineering, Graduate School of Engineering, Kyoto University, Kyoto, Kyoto 616-8540, Japan
| | - Shigeru Kondo
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan
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2
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Sugiura K, Terano T, Adachi H, Hagiwara J, Matsuda K, Nishida K, Hanson P, Kondo S, Gotoh H. Histological Observation of Helmet Development in the Treehopper Poppea capricornis (Insecta: Hemiptera: Membracidae). Zoolog Sci 2024; 41:167-176. [PMID: 38587911 DOI: 10.2108/zs230039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Accepted: 11/09/2023] [Indexed: 04/10/2024]
Abstract
The treehoppers (Hemiptera, Membracidae) are known for possessing a large three-dimensional structure called a helmet. Although some ecological functions of the helmet have already been elucidated, the developmental mechanisms underlying the complex and diverse morphology of the helmet are still largely unknown. The process of helmet formation was first described in Antianthe expansa, which possesses a simple roof-shaped helmet. However, the developmental process in species with more complex helmet morphologies remains largely unexplored. Hence, in this study, we used Poppea capricornis, which possesses a more complex helmet structure than A. expansa, to investigate the helmet development using paraffin sections, micro-CT, and scanning electronic microscopy. Our focus was on the overall helmet developmental process common to both species and formation of structures unique to Poppea and its comparison to Antianthe. As a result, we discovered that miniature structures were also formed in Poppea, similar to Antianthe, during the helmet formation. Common structures that were shared between the two species were discernible at this stage. Additionally, we observed that suprahumeral horns and posterior horns, two morphological traits specific to the Poppea helmet that are apparently similar anatomically, are formed through two distinctly different developmental mechanisms. The suprahumeral horns appeared to be formed by utilizing the nymphal suprahumeral bud as a mold, while we could not detect any nymphal structures potentially used for a mold in the posterior horns formation. Our findings suggest that the helmet formation mechanisms of Antianthe and Poppea employ a common mechanism but form species-specific structures by multiple mechanisms.
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Affiliation(s)
- Kanta Sugiura
- Department of Biological Science, Faculty of Science, Shizuoka University, Suruga Ward, Shizuoka City, Shizuoka 422-8529, Japan
- Department of Science, Graduate School of Integrated Science and Technology, Shizuoka University, Suruga-ku, Shizuoka City, Shizuoka 422-8529, Japan
| | - Tensho Terano
- Department of Biological Science, Faculty of Science, Shizuoka University, Suruga Ward, Shizuoka City, Shizuoka 422-8529, Japan
| | - Haruhiko Adachi
- Graduate School of Frontier Biosciences, Osaka University, Osaka 565-0871, Japan
| | - Jin Hagiwara
- Department of Biological Science, Faculty of Science, Shizuoka University, Suruga Ward, Shizuoka City, Shizuoka 422-8529, Japan
- Graduate School of Frontier Biosciences, Osaka University, Osaka 565-0871, Japan
| | - Keisuke Matsuda
- Graduate School of Frontier Biosciences, Osaka University, Osaka 565-0871, Japan
| | - Kenji Nishida
- Associate Researcher Museo de Zoología, Universidad de Costa Rica & Estación Biológica Monteverde, Apdo 22-5655, Monteverde, CostaRica
| | - Paul Hanson
- Escuela de Biología & Centro de Investigacion en Biodiversidad y Ecología Tropical (CIBET), Universidad de Costa Rica, San Pedro de Montes de Oca, San José, Costa Rica
| | - Shigeru Kondo
- Graduate School of Frontier Biosciences, Osaka University, Osaka 565-0871, Japan
| | - Hiroki Gotoh
- Department of Biological Science, Faculty of Science, Shizuoka University, Suruga Ward, Shizuoka City, Shizuoka 422-8529, Japan,
- Department of Science, Graduate School of Integrated Science and Technology, Shizuoka University, Suruga-ku, Shizuoka City, Shizuoka 422-8529, Japan
- Division of Bioscience, Graduate School of Science and Technology, Shizuoka University, Hamamatsu City, Shizuoka 432-8011, Japan
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3
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Morikawa K, Morita S, Sakura K, Maeno A, Gotoh H, Niimi T, Inoue Y. Unveiling the role of differential growth in 3D morphogenesis: An inference method to analyze area expansion rate distribution in biological systems. J Theor Biol 2023; 575:111650. [PMID: 37884223 DOI: 10.1016/j.jtbi.2023.111650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 10/17/2023] [Accepted: 10/20/2023] [Indexed: 10/28/2023]
Abstract
The three-dimensional (3D) morphologies of many organs in organisms, such as the curved shapes of leaves and flowers, the branching structure of lungs, and the exoskeletal shape of insects, are formed through surface growth. Although differential growth, a mode of surface growth, has been qualitatively identified as 3D morphogenesis, a quantitative understanding of the mechanical contribution of differential growth is lacking. To address this, we developed a quantitative inference method to analyze the distribution of the area expansion rate, which governs the growth of surfaces into 3D morphology. To validate the accuracy of our method, we tested it on a basic 3D morphology that allowed for the theoretical derivation of the area expansion rate distribution, and then assessed the difference between the predicted outcome and the theoretical solution. We also applied this method to complex 3D shapes and evaluated its accuracy through numerical experiments. The findings of the study revealed a linear decrease in error on a log-log scale with an increase in the number of meshes in both evaluations. This affirmed the reliability of the predictions for meshes that are sufficiently refined. Moreover, we employed our methodology to analyze the developmental process of the Japanese rhinoceros beetle Trypoxylus dichotomus, which is characterized by differential growth regulating 3D morphogenesis. The results indicated a notably high rate of area expansion on the left and right edges of the horn primordium, which is consistent with the experimental evidence of a higher rate of cell division in these regions. Hence, these findings confirm the efficacy of the proposed method in analyzing biological systems.
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Affiliation(s)
- Kentaro Morikawa
- Department of Micro Engineering, Graduate School of Engineering, Kyoto University, Japan.
| | - Shinichi Morita
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, Japan; Basic Biology Program, Graduate Institute for Advanced Studies, The Graduate University for Advanced Studies, SOKENDAI, Japan
| | - Kazuki Sakura
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, Japan
| | | | - Hiroki Gotoh
- Department of Biological Science, Faculty of Science, Shizuoka University, Japan
| | - Teruyuki Niimi
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, Japan; Basic Biology Program, Graduate Institute for Advanced Studies, The Graduate University for Advanced Studies, SOKENDAI, Japan
| | - Yasuhiro Inoue
- Department of Micro Engineering, Graduate School of Engineering, Kyoto University, Japan.
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4
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Weber JN, Kojima W, Boisseau RP, Niimi T, Morita S, Shigenobu S, Gotoh H, Araya K, Lin CP, Thomas-Bulle C, Allen CE, Tong W, Lavine LC, Swanson BO, Emlen DJ. Evolution of horn length and lifting strength in the Japanese rhinoceros beetle Trypoxylus dichotomus. Curr Biol 2023; 33:4285-4297.e5. [PMID: 37734374 DOI: 10.1016/j.cub.2023.08.066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 06/28/2023] [Accepted: 08/23/2023] [Indexed: 09/23/2023]
Abstract
What limits the size of nature's most extreme structures? For weapons like beetle horns, one possibility is a tradeoff associated with mechanical levers: as the output arm of the lever system-the beetle horn-gets longer, it also gets weaker. This "paradox of the weakening combatant" could offset reproductive advantages of additional increases in weapon size. However, in contemporary populations of most heavily weaponed species, males with the longest weapons also tend to be the strongest, presumably because selection drove the evolution of compensatory changes to these lever systems that ameliorated the force reductions of increased weapon size. Therefore, we test for biomechanical limits by reconstructing the stages of weapon evolution, exploring whether initial increases in weapon length first led to reductions in weapon force generation that were later ameliorated through the evolution of mechanisms of mechanical compensation. We describe phylogeographic relationships among populations of a rhinoceros beetle and show that the "pitchfork" shaped head horn likely increased in length independently in the northern and southern radiations of beetles. Both increases in horn length were associated with dramatic reductions to horn lifting strength-compelling evidence for the paradox of the weakening combatant-and these initial reductions to horn strength were later ameliorated in some populations through reductions to horn length or through increases in head height (the input arm for the horn lever system). Our results reveal an exciting geographic mosaic of weapon size, weapon force, and mechanical compensation, shedding light on larger questions pertaining to the evolution of extreme structures.
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Affiliation(s)
- Jesse N Weber
- Department of Integrative Biology, University of Wisconsin-Madison, Madison, WI 53706, USA.
| | - Wataru Kojima
- Graduate School of Sciences and Technology for Innovation, Yamaguchi University, 1677-1 Yoshida, Yamaguchi 753-8511, Japan
| | - Romain P Boisseau
- Division of Biological Sciences, The University of Montana, Missoula, MT 59812, USA
| | - Teruyuki Niimi
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38 Nishigonaka Myodaiji, Okazaki 444-8585, Japan
| | - Shinichi Morita
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38 Nishigonaka Myodaiji, Okazaki 444-8585, Japan
| | - Shuji Shigenobu
- Trans-Scale Biology Center, National Institute for Basic Biology, 38 Nishigonaka Myodaiji, Okazaki 444-8585, Japan
| | - Hiroki Gotoh
- Department of Science, Graduate School of Integrated Science and Technology, Shizuoka University, 836 Oya, Suruga Ward, Shizuoka, Japan
| | - Kunio Araya
- Faculty of Social and Cultural Studies, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka-city Fukuoka 819-0395, Japan
| | - Chung-Ping Lin
- Department of Life Science, National Taiwan Normal University, No.88 Sec. 4, Tingzhou Rd, Taipei 11677, Taiwan
| | - Camille Thomas-Bulle
- Division of Biological Sciences, The University of Montana, Missoula, MT 59812, USA; Department of Biological Sciences, University of Denver, Denver, CO 80208, USA
| | - Cerisse E Allen
- Division of Biological Sciences, The University of Montana, Missoula, MT 59812, USA
| | - Wenfei Tong
- Cornell Laboratory of Ornithology, Ithaca, NY 14850, USA
| | - Laura Corley Lavine
- Department of Entomology, Washington State University, Pullman, WA 99164, USA
| | - Brook O Swanson
- Department of Biology, Gonzaga University, 502 East Boone Avenue, Spokane, WA 99258-0102, USA
| | - Douglas J Emlen
- Division of Biological Sciences, The University of Montana, Missoula, MT 59812, USA.
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5
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Morita S, Shibata TF, Nishiyama T, Kobayashi Y, Yamaguchi K, Toga K, Ohde T, Gotoh H, Kojima T, Weber JN, Salvemini M, Bino T, Mase M, Nakata M, Mori T, Mori S, Cornette R, Sakura K, Lavine LC, Emlen DJ, Niimi T, Shigenobu S. The draft genome sequence of the Japanese rhinoceros beetle Trypoxylus dichotomus septentrionalis towards an understanding of horn formation. Sci Rep 2023; 13:8735. [PMID: 37253792 DOI: 10.1038/s41598-023-35246-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Accepted: 05/15/2023] [Indexed: 06/01/2023] Open
Abstract
The Japanese rhinoceros beetle Trypoxylus dichotomus is a giant beetle with distinctive exaggerated horns present on the head and prothoracic regions of the male. T. dichotomus has been used as a research model in various fields such as evolutionary developmental biology, ecology, ethology, biomimetics, and drug discovery. In this study, de novo assembly of 615 Mb, representing 80% of the genome estimated by flow cytometry, was obtained using the 10 × Chromium platform. The scaffold N50 length of the genome assembly was 8.02 Mb, with repetitive elements predicted to comprise 49.5% of the assembly. In total, 23,987 protein-coding genes were predicted in the genome. In addition, de novo assembly of the mitochondrial genome yielded a contig of 20,217 bp. We also analyzed the transcriptome by generating 16 RNA-seq libraries from a variety of tissues of both sexes and developmental stages, which allowed us to identify 13 co-expressed gene modules. We focused on the genes related to horn formation and obtained new insights into the evolution of the gene repertoire and sexual dimorphism as exemplified by the sex-specific splicing pattern of the doublesex gene. This genomic information will be an excellent resource for further functional and evolutionary analyses, including the evolutionary origin and genetic regulation of beetle horns and the molecular mechanisms underlying sexual dimorphism.
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Grants
- 23128505, 25128706, 16H01452, 18H04766, 20H04933, 20H05944, 17H06384, 22128008, 19K16181, 21K15135 Japan Society for the Promotion of Science
- 23128505, 25128706, 16H01452, 18H04766, 20H04933, 20H05944, 17H06384, 22128008, 19K16181, 21K15135 Japan Society for the Promotion of Science
- 23128505, 25128706, 16H01452, 18H04766, 20H04933, 20H05944, 17H06384, 22128008, 19K16181, 21K15135 Japan Society for the Promotion of Science
- 23128505, 25128706, 16H01452, 18H04766, 20H04933, 20H05944, 17H06384, 22128008, 19K16181, 21K15135 Japan Society for the Promotion of Science
- IOS-1456133 National Science Foundation
- IOS-1456133 National Science Foundation
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Affiliation(s)
- Shinichi Morita
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, Okazaki, Japan
- Department of Basic Biology, School of Life Science, The Graduate University for Advanced Studies, SOKENDAI, Okazaki, Japan
| | - Tomoko F Shibata
- Division of Evolutionary Biology, National Institute for Basic Biology, Okazaki, Japan
| | - Tomoaki Nishiyama
- Division of Integrated Omics Research, Research Center for Experimental Modeling of Human Disease, Kanazawa University, Kanazawa, Japan
| | - Yuuki Kobayashi
- Laboratory of Evolutionary Genomics, National Institute for Basic Biology, Okazaki, Japan
| | - Katsushi Yamaguchi
- Trans-Omics Facility, National Institute for Basic Biology, Okazaki, Japan
| | - Kouhei Toga
- Laboratory of Sericulture and Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
- URA Division, Office of Research and Academia-Government-Community Collaboration, Hiroshima University, Hiroshima, Japan
| | - Takahiro Ohde
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, Okazaki, Japan
- Laboratory of Sericulture and Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
- Department of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Hiroki Gotoh
- Laboratory of Sericulture and Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
- Department of Biological Science, Faculty of Science, Shizuoka University, Shizuoka, Japan
| | - Takaaki Kojima
- Laboratory of Molecular Biotechnology, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
- Department of Agrobiological Resources, Faculty of Agriculture, Meijo University, Nagoya, Japan
| | - Jesse N Weber
- Department of Integrative Biology, University of Wisconsin-Madison, Madison, WI, USA
| | - Marco Salvemini
- Department of Biology, University of Naples Federico II, Naples, Italy
| | - Takahiro Bino
- Trans-Omics Facility, National Institute for Basic Biology, Okazaki, Japan
| | - Mutsuki Mase
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, Okazaki, Japan
- Laboratory of Sericulture and Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
| | - Moe Nakata
- Laboratory of Sericulture and Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
| | - Tomoko Mori
- Trans-Omics Facility, National Institute for Basic Biology, Okazaki, Japan
| | - Shogo Mori
- Trans-Omics Facility, National Institute for Basic Biology, Okazaki, Japan
| | - Richard Cornette
- Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Tsukuba, Japan
| | - Kazuki Sakura
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, Okazaki, Japan
| | - Laura C Lavine
- Department of Entomology, Washington State University, Pullman, WA, USA
| | - Douglas J Emlen
- Division of Biological Sciences, The University of Montana, Missoula, MT, USA
| | - Teruyuki Niimi
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, Okazaki, Japan.
- Department of Basic Biology, School of Life Science, The Graduate University for Advanced Studies, SOKENDAI, Okazaki, Japan.
- Laboratory of Sericulture and Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan.
| | - Shuji Shigenobu
- Department of Basic Biology, School of Life Science, The Graduate University for Advanced Studies, SOKENDAI, Okazaki, Japan.
- Laboratory of Evolutionary Genomics, National Institute for Basic Biology, Okazaki, Japan.
- Trans-Omics Facility, National Institute for Basic Biology, Okazaki, Japan.
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6
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Ohtsu I, Chikami Y, Umino T, Gotoh H. Evaluation of Body Size Indicators for Morphological Analyses in Two Sister Species of Genus Dorcus (Coleoptera, Lucanidae). J Insect Sci 2022; 22:7. [PMID: 36130316 PMCID: PMC9492273 DOI: 10.1093/jisesa/ieac054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Indexed: 06/15/2023]
Abstract
The relationship between trait and body size, i.e., the scaling relationship or static allometry, is an essential concept for investigating trait size. However, usage of an inappropriate body size indicator can lead to misinterpretation of morphology. In this study, we examined several possible body size indicators in two closely related stag beetle species, Dorcus rectus and Dorcus amamianus. We raised animals in captivity and used pupal weight as a measure of true, or overall body size, and then evaluated six adult morphological traits to test whether these traits could be reliably used as body size indicators in static scaling relationship comparisons. We analyzed two comparisons, between sexes in same species and between species in same sex. We showed that the most appropriate body size indicators differ depending on the comparisons. Our results indicated that the scaling relationship of focal traits could be over- or under-estimated depending on which body size indicators are used.
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Affiliation(s)
- Itsuki Ohtsu
- Department of Science, Graduate School of Integrated Science and Technology, Shizuoka University, Suruga-ku, Shizuoka, 422-8529, Japan
| | - Yasuhiko Chikami
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, Okazaki, Aichi, 444-8585, Japan
| | - Taichi Umino
- Sugadaira Research Station, Mountain Science Center, University of Tsukuba, Ueda, Nagano, 386-2204, Japan
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7
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Morita S, Sakura K, Gotoh H, Emlen DJ, Niimi T. Recent advances in understanding horn formation in the Japanese rhinoceros beetle Trypoxylus dichotomus using next-generation sequencing technology. Curr Opin Insect Sci 2022; 51:100901. [PMID: 35301164 DOI: 10.1016/j.cois.2022.100901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 02/20/2022] [Accepted: 03/04/2022] [Indexed: 06/14/2023]
Abstract
The exaggerated horns of beetles are attractive models for studying the origin of novel traits and morphological evolution. Closely related species often differ profoundly in the size, number, and shape of their horns, and in the body region from which they extend. In addition, beetle horns exhibit exquisite nutrition-dependent phenotypic plasticity, leading to disproportionate growth of the horns in the largest, best-condition individuals and much smaller - even stunted - horn sizes in poor-condition individuals. These exciting phenomena in beetle horns have recently been revealed at the molecular level with the advent of next-generation sequencing. This section reviews the latest research on a horned beetle, the Japanese rhinoceros beetle Trypoxylus dichotomus, whose genome was recently sequenced.
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Affiliation(s)
- Shinichi Morita
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki 444-8585, Japan; Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa, Nagoya 464-8601, Japan
| | - Kazuki Sakura
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki 444-8585, Japan
| | - Hiroki Gotoh
- Department of Biological Science, Faculty of Sciences, Shizuoka University, Shizuoka 422-8529, Japan
| | - Douglas J Emlen
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
| | - Teruyuki Niimi
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki 444-8585, Japan; Department of Basic Biology, School of Life Science, The Graduate University for Advanced Studies, SOKENDAI, 38 Nishigonaka, Myodaiji, Okazaki 444-8585, Japan.
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8
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Miyazaki S, Fujiwara K, Kai K, Masuoka Y, Gotoh H, Niimi T, Hayashi Y, Shigenobu S, Maekawa K. Evolutionary transition of doublesex regulation from sex-specific splicing to male-specific transcription in termites. Sci Rep 2021; 11:15992. [PMID: 34362973 PMCID: PMC8346542 DOI: 10.1038/s41598-021-95423-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 07/20/2021] [Indexed: 12/13/2022] Open
Abstract
The sex determination gene doublesex (dsx) encodes a transcription factor with two domains, oligomerization domain 1 (OD1) and OD2, and is present throughout insects. Sex-specific Dsx splicing isoforms regulate the transcription of target genes and trigger sex differentiation in all Holometabola examined to date. However, in some hemimetabolous insects, dsx is not spliced sexually and its sequence is less conserved. Here, to elucidate evolutionary changes in dsx in domain organisation and regulation in termites, we searched genome and/or transcriptome databases for the dsx OD1 and OD2 in seven termite species and their sister group (Cryptocercus woodroaches). Molecular phylogenetic and synteny analyses identified OD1 sequences of termites and C. punctulatus that clustered with dsx of Holometabola and regarded them as dsx orthologues. The Cryptocercus dsx orthologue containing OD2 was spliced sexually, as previously shown in other insects. However, OD2 was not found in all termite dsx orthologues. These orthologues were encoded by a single exon in three termites for which genome information is available; they were not alternatively spliced but transcribed in a male-specific manner in two examined species. Evolution of dsx regulation from sex-specific splicing to male-specific transcription may have occurred at an early stage of social evolution in termites.
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Affiliation(s)
- Satoshi Miyazaki
- Graduate School of Agriculture, Tamagawa University, Machida, Tokyo, 194-8610, Japan.
| | - Kokuto Fujiwara
- Graduate School of Science and Engineering, University of Toyama, Gofuku, Toyama, 930-8555, Japan
| | - Keima Kai
- Graduate School of Science and Engineering, University of Toyama, Gofuku, Toyama, 930-8555, Japan
| | - Yudai Masuoka
- Graduate School of Science and Engineering, University of Toyama, Gofuku, Toyama, 930-8555, Japan.,Institute of Agrobiological Sciences, NARO (National Agriculture and Food Research Organization), Tsukuba, Ibaraki, 305-8634, Japan
| | - Hiroki Gotoh
- Department of Biological Science, Faculty of Science, Shizuoka University, Suruga-ku, Shizuoka, 422-8529, Japan
| | - Teruyuki Niimi
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, Okazaki, Aichi, 444-8585, Japan.,Department of Basic Biology, School of Life Science, The Graduate University for Advanced Studies, SOKENDAI, Okazaki, Aichi, 444-8585, Japan
| | - Yoshinobu Hayashi
- Department of Biology, Keio University, Yokohama, Kanagawa, 223-8521, Japan
| | - Shuji Shigenobu
- Department of Basic Biology, School of Life Science, The Graduate University for Advanced Studies, SOKENDAI, Okazaki, Aichi, 444-8585, Japan.,NIBB Research Core Facilities, National Institute for Basic Biology, Okazaki, Aichi, 444-8585, Japan
| | - Kiyoto Maekawa
- Faculty of Science, Academic Assembly, University of Toyama, Gofuku, Toyama, 930-8555, Japan.
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9
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Gotoh H, Adachi H, Matsuda K, Lavine LC. Epithelial folding determines the final shape of beetle horns. Curr Opin Genet Dev 2021; 69:122-128. [PMID: 33848957 DOI: 10.1016/j.gde.2021.03.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 03/08/2021] [Accepted: 03/11/2021] [Indexed: 11/18/2022]
Abstract
The elaborate ornaments and weapons of sexual selection, such as the vast array of horns observed in scarab beetles, are some of the most striking outcomes of evolution. How these novel traits have arisen, develop, and respond to condition is governed by a complex suite of interactions that require coordination between the environment, whole-animal signals, cell-cell signals, and within-cell signals. Endocrine factors, developmental patterning genes, and sex-specific gene expression have been shown to regulate beetle horn size, shape, and location, yet no overarching mechanism of horn shape has been described. Recent advances in microscopy and computational analyses combined with a functional genetic approach have revealed that patterning genes combined with intricate epithelial folding and movement are responsible for the final shape of a beetle head horn.
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Affiliation(s)
- Hiroki Gotoh
- Ecological Genetics Laboratory, Department of Genomics and Evolutionary Biology, National Institute of Genetics, Mishima, Shizuoka, 401-8540, Japan
| | - Haruhiko Adachi
- Graduate School of Frontier Bioscience, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Keisuke Matsuda
- Graduate School of Frontier Bioscience, Osaka University, Suita, Osaka, 565-0871, Japan; Osaka University Hospital, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Laura C Lavine
- Department of Entomology, Washington State University, Pullman, WA, 99163 USA.
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10
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Adachi H, Matsuda K, Niimi T, Kondo S, Gotoh H. Genetical control of 2D pattern and depth of the primordial furrow that prefigures 3D shape of the rhinoceros beetle horn. Sci Rep 2020; 10:18687. [PMID: 33122767 PMCID: PMC7596553 DOI: 10.1038/s41598-020-75709-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 10/06/2020] [Indexed: 02/06/2023] Open
Abstract
The head horn of the Asian rhinoceros beetle develops as an extensively folded primordium before unfurling into its final 3D shape at the pupal molt. The information of the final 3D structure of the beetle horn is prefigured in the folding pattern of the developing primordium. However, the developmental mechanism underlying epithelial folding of the primordium is unknown. In this study, we addressed this gap in our understanding of the developmental patterning of the 3D horn shape of beetles by focusing on the formation of furrows at the surface of the primordium that become the bifurcated 3D shape of the horn. By gene knockdown analysis via RNAi, we found that knockdown of the gene Notch disturbed overall horn primordial furrow depth without affecting the 2D furrow pattern. In contrast, knockdown of CyclinE altered 2D horn primordial furrow pattern without affecting furrow depth. Our results show how the depth and 2D pattern of primordial surface furrows are regulated at least partially independently during beetle horn development, and how both can alter the final 3D shape of the horn.
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Affiliation(s)
- Haruhiko Adachi
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Keisuke Matsuda
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, 565-0871, Japan.,Osaka University Hospital, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Teruyuki Niimi
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, Okazaki, Aichi, 444-8585, Japan
| | - Shigeru Kondo
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Hiroki Gotoh
- Ecological Genetics Laboratory, Department of Genomics and Evolutionary Biology, National Institute of Genetics, Mishima, Shizuoka, 411-8540, Japan.
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11
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Adachi H, Matsuda K, Nishida K, Hanson P, Kondo S, Gotoh H. Structure and development of the complex helmet of treehoppers (Insecta: Hemiptera: Membracidae). Zoological Lett 2020; 6:3. [PMID: 32123574 PMCID: PMC7041272 DOI: 10.1186/s40851-020-00155-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 02/14/2020] [Indexed: 05/08/2023]
Abstract
Some insects possess complex three-dimensional (3D) structures that develop under the old cuticle prior to the last imaginal molt. Adult treehoppers (Insecta: Hemiptera: Auchenorrhyncha: Membracidae) have one such complex 3D structure, known as a helmet, on their dorsal side. The adult helmet likely forms inside the nymphal pronotum during the final instar nymphal stage. Previous morphological studies have reported that the adult helmet is a large, bi-layered, plywood-like structure, whereas the nymphal pronotum is a monolayer, sheath-like structure. The adult helmet is much larger than nymphal helmet. Thus, the emergence of the adult helmet involves two structural transitions: a transition from a monolayer, sheath-like pronotum to a bi-layer, plywood-like helmet, and a transition in size from small to large. However, when, how, and in what order these transitions occur within the nymphal cuticle is largely unknown. To determine how adult helmet development occurs under the nymphal cuticle, in the present study we describe the morphology of the final adult helmet and investigate developmental trajectories of the helmet during the final instar nymphal stage. We used micro-CT, scanning electron microscope and paraffin sections for morphological observations, and used Antianthe expansa as a model species. We found that the structural transition (from monolayer, sheath-like structure to bi-layer, roof-like structure) occurs through the formation of a "miniature" of the adult helmet during the middle stage of development and that subsequently, extensive folding and furrows form, which account for the increase in size. We suggest that the making of a "miniature" is the key developmental step for the formation of various 3D structures of treehopper helmets.
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Affiliation(s)
- Haruhiko Adachi
- Graduate School of Frontier Bioscience, Osaka University, Suita, Osaka Japan
| | - Keisuke Matsuda
- Graduate School of Frontier Bioscience, Osaka University, Suita, Osaka Japan
| | - Kenji Nishida
- Collaborator, Museo de Zoología, Universidad de Costa Rica and Estación Biológica Monteverde, Monteverde, Puntarenas, Costa Rica
| | - Paul Hanson
- Escuela de Biología, Universidad de Costa Rica, San Pedro de Montes de Oca, San José, Costa Rica
| | - Shigeru Kondo
- Graduate School of Frontier Bioscience, Osaka University, Suita, Osaka Japan
| | - Hiroki Gotoh
- Faculty of Environmental Earth Sciences, Hokkaido University, Sapporo, Hokkaido Japan
- Ecological Genetics Laboratory, Department of Genomics and Evolutionary Biology, National Institute of Genetics, Mishima, Shizuoka 411-8540 Japan
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12
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Lavine MD, Gotoh H, Hayes A, Corley Lavine L. The Insulin Signaling Substrate Chico and the Ecdysone Response Element Broad Both Regulate Growth of the Head Horns in the Asian Rhinoceros Beetle, Trypoxylus dichotomus. Integr Comp Biol 2019; 59:1338-1345. [PMID: 31165143 DOI: 10.1093/icb/icz093] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Males of the Asian rhinoceros beetle, Trypoxylus dichotomus, possess exaggerated head and thoracic horns that scale dramatically out of proportion to body size. While RNAi-mediated knockdowns of the insulin receptor suggest that the insulin signaling pathway regulates nutrition-dependent growth including exaggerated horns, the genes that regulate disproportionate growth have yet to be identified. We used RNAi-mediated knockdown of several genes to investigate their potential role in growth and scaling of the sexually dimorphic, exaggerated head horns of T. dichotomus. Knockdown of the insulin signaling substrate chico and the ecdysone response element broad caused significant decreases in head horn length, while having no or minimal effects on other structures such as elytra and tibiae. However, scaling of horns to body size was not affected by either knockdown. In addition, knockdown of phosphatase and tensin homolog, a negative regulator of the insulin signaling pathway, had no significant effects on any trait. Our results do not identify any candidate genes that may specifically mediate the allometric aspect of horn growth, but they do confirm the insulin signaling pathway as a mediator of conditional trait expression, and importantly implicate the ecdysone signaling pathway, possibly in conjunction with insulin signaling, as an additional mediator of horn growth.
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Affiliation(s)
- Mark D Lavine
- Department of Entomology, Washington State University, Pullman, WA 99164, USA
| | - Hiroki Gotoh
- Faculty of Environmental Earth Sciences, Hokkaido University, Sapporo, Hokkaido 0600810, Japan
| | - Abigail Hayes
- Department of Entomology, Washington State University, Pullman, WA 99164, USA
| | - Laura Corley Lavine
- Department of Entomology, Washington State University, Pullman, WA 99164, USA
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13
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Tsuji T, Gotoh H, Morita S, Hirata J, Minakuchi Y, Yaginuma T, Toyoda A, Niimi T. Molecular Characterization of Eye Pigmentation-Related ABC Transporter Genes in the Ladybird Beetle Harmonia axyridis Reveals Striking Gene Duplication of the white Gene. Zoolog Sci 2019; 35:260-267. [PMID: 29882491 DOI: 10.2108/zs170166] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Many species of ladybird beetles (Coccinellidae) possess vivid body colors. These colors and patterns show diversity between coccinellid species, or even within species. However, the molecular underpinnings of these striking body colors are scarcely understood. One of the candidate pigmentation molecules responsible for ladybird body color is ommochrome pigment, which is well known as the red pigment molecule responsible for the red eyes of Drosophila. Various insects also use ommochrome in body coloration. It is known that ommochrome pigment precursors are imported into appropriate cells by the ATP binding cassette (ABC) transporter proteins White and Scarlet. Thus, these ABC transporter genes are potentially involved in various color and pattern expressions seen in ladybird beetle species. In this study, in order to identify the repertory of ABC transporter genes responsible for such body colors, we performed molecular characterization of pigment-related ABC transporter genes, especially white and scarlet, in the coccinellid Harmonia axyridis. By using whole genome data for H. axyridis and subsequent RACE-PCR, six white orthologs and one scarlet ortholog were successfully identified. According to the results of functional analyses via RNA interference (RNAi), only one of these genes had a major function in eye pigmentation. Specific effects on body color and pattern were not detected by our RNAi experiments of any of these genes. This is the first report of this striking duplication of white genes and their functional analyses in insects.
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Affiliation(s)
- Tomohiro Tsuji
- 1 Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan
| | - Hiroki Gotoh
- 1 Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan
| | - Shinichi Morita
- 2 Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38, Nishigonaka, Myodaiji, Okazaki 444-8585, Japan
| | - Junya Hirata
- 1 Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan
| | - Yohei Minakuchi
- Comparative Genomics Laboratory, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
| | - Toshinobu Yaginuma
- 1 Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan
| | - Atsushi Toyoda
- Comparative Genomics Laboratory, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan.,4 Advanced Genomics Center, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
| | - Teruyuki Niimi
- 1 Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan.,2 Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38, Nishigonaka, Myodaiji, Okazaki 444-8585, Japan.,5 Department of Basic Biology, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi 444-8585, Japan
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14
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Sugime Y, Oguchi K, Gotoh H, Hayashi Y, Matsunami M, Shigenobu S, Koshikawa S, Miura T. Termite soldier mandibles are elongated by dachshund under hormonal and Hox gene controls. Development 2019; 146:dev.171942. [PMID: 30833380 DOI: 10.1242/dev.171942] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 02/12/2019] [Indexed: 11/20/2022]
Abstract
In social insects, interactions among colony members trigger caste differentiation with morphological modifications. In termite soldier differentiation, the mandible size considerably increases through two moltings (via the presoldier stage) under the control of juvenile hormone (JH). Regulatory genes are predicted to provide patterning information that induces the mandible-specific cell proliferation. To identify factors responsible for the mandibular enlargement, expression analyses of 18 candidate genes were carried out in the termite Hodotermopsis sjostedti Among those, dachshund (dac), which identifies the intermediate domain along the proximodistal appendage axis, showed mandible-specific upregulation prior to the molt into presoldiers, which can explain the pattern of cell proliferation for the mandibular elongation. Knockdown of dac by RNAi reduced the mandibular length and distorted its morphology. Furthermore, the epistatic relationships among Methoprene tolerant, Insulin receptor, Deformed (Dfd) and dac were revealed by combined RNAi and qRT-PCR analyses, suggesting that dac is regulated by Dfd, downstream of the JH and insulin signaling pathways. Thus, caste-specific morphogenesis is controlled by interactions between the factors that provide spatial information and physiological status.
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Affiliation(s)
- Yasuhiro Sugime
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, 060-0810, Japan
| | - Kohei Oguchi
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, 060-0810, Japan.,Misaki Marine Biological Station, Graduate School of Science, The University of Tokyo, Miura, Kanagawa, 238-0225, Japan
| | - Hiroki Gotoh
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, 060-0810, Japan.,Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi, 464-8601, Japan
| | - Yoshinobu Hayashi
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, 060-0810, Japan.,Department of Biology, Keio University, Yokohama, Kanagawa, 223-8521, Japan
| | - Masatoshi Matsunami
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, 060-0810, Japan.,Graduate School of Medicine, University of the Ryukyus, Nishihara, Okinawa, 903-0215, Japan
| | - Shuji Shigenobu
- NIBB Core Research Facilities, National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, 444-8585, Japan
| | - Shigeyuki Koshikawa
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, 060-0810, Japan
| | - Toru Miura
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, 060-0810, Japan .,Misaki Marine Biological Station, Graduate School of Science, The University of Tokyo, Miura, Kanagawa, 238-0225, Japan
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15
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Shinji J, Gotoh H, Miyanishi H, Lavine MD, Lavine LC. The activin signaling transcription factor Smox is an essential regulator of appendage size during regeneration after autotomy in the crayfish. Evol Dev 2018; 21:44-55. [DOI: 10.1111/ede.12277] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Junpei Shinji
- Department of Entomology; Washington State University; Pullman Washington
| | - Hiroki Gotoh
- Graduate School of Bioagricultural Sciences; Nagoya University, Furo-cho, Chikusa-ku; Nagoya Japan
| | - Hiroshi Miyanishi
- Faculty of Agriculture; University of Miyazaki, Gakuen-kibanadai-nishi; Miyazaki Japan
| | - Mark D. Lavine
- Department of Entomology; Washington State University; Pullman Washington
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16
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Zinna R, Emlen D, Lavine LC, Johns A, Gotoh H, Niimi T, Dworkin I. Sexual dimorphism and heightened conditional expression in a sexually selected weapon in the Asian rhinoceros beetle. Mol Ecol 2018; 27:5049-5072. [PMID: 30357984 DOI: 10.1111/mec.14907] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 09/27/2018] [Accepted: 10/01/2018] [Indexed: 12/12/2022]
Abstract
Among the most dramatic examples of sexual selection are the weapons used in battles between rival males over access to females. As with ornaments of female choice, the most "exaggerated" sexually selected weapons vary from male to male more widely than other body parts (hypervariability), and their growth tends to be more sensitive to nutritional state or physiological condition compared with growth of other body parts ("heightened" conditional expression). Here, we use RNAseq analysis to build on recent work exploring these mechanisms in the exaggerated weapons of beetles, by examining patterns of differential gene expression in exaggerated (head and thorax horns) and non-exaggerated (wings, genitalia) traits in the Asian rhinoceros beetle, Trypoxylus dichotomus. Our results suggest that sexually dimorphic expression of weaponry involves large-scale changes in gene expression, relative to other traits, while nutrition-driven changes in gene expression in these same weapons are less pronounced. However, although fewer genes overall were differentially expressed in high- vs. low-nutrition individuals, the number of differentially expressed genes varied predictably according to a trait's degree of condition dependence (head horn > thorax horn > wings > genitalia). Finally, we observed a high degree of similarity in direction of effects (vectors) for subsets of differentially expressed genes across both sexually dimorphic and nutritionally responsive growth. Our results are consistent with a common set of mechanisms governing sexual size dimorphism and condition dependence.
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Affiliation(s)
- Robert Zinna
- Department of Biology, McMaster University, Hamilton, Ontario, Canada
| | - Douglas Emlen
- Department of Biology, McMaster University, Hamilton, Ontario, Canada
| | - Laura C Lavine
- Department of Biology, McMaster University, Hamilton, Ontario, Canada
| | - Annika Johns
- Department of Biology, McMaster University, Hamilton, Ontario, Canada
| | - Hiroki Gotoh
- Department of Biology, McMaster University, Hamilton, Ontario, Canada
| | - Teruyuki Niimi
- Department of Biology, McMaster University, Hamilton, Ontario, Canada
| | - Ian Dworkin
- Department of Biology, McMaster University, Hamilton, Ontario, Canada
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17
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Adachi H, Matsuda K, Niimi T, Inoue Y, Kondo S, Gotoh H. Anisotropy of cell division and epithelial sheet bending via apical constriction shape the complex folding pattern of beetle horn primordia. Mech Dev 2018; 152:32-37. [DOI: 10.1016/j.mod.2018.06.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 06/15/2018] [Accepted: 06/15/2018] [Indexed: 11/29/2022]
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18
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Hikita H, Sato M, Endo M, Sato M, Soroida Y, Kobayashi T, Gotoh H, Iwai T, Nakagomi R, Tateishi R, Komuro T, Sone S, Koike K, Yatomi Y, Ikeda H. Disappearance of perihepatic lymph node enlargement after hepatitis C viral eradication with direct-acting antivirals. J Viral Hepat 2018; 25:329-334. [PMID: 29091333 DOI: 10.1111/jvh.12819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 09/19/2017] [Indexed: 12/09/2022]
Abstract
Perihepatic lymph node enlargement (PLNE) which has been shown to be negatively associated with hepatocellular carcinoma (HCC) occurrence is frequently observed in chronic liver disease; however, changes in the state of perihepatic lymph nodes after eradication of hepatitis C virus (HCV) have not been investigated yet. We aimed to evaluate this issue. We enrolled 472 patients with chronic HCV infection who achieved viral eradication with direct-acting antivirals (DAA). We investigated whether the status of perihepatic lymph nodes changed before and after HCV eradication (primary endpoint). We also evaluated the association between PLNE and clinical findings such as liver fibrosis or hepatocellular injury before HCV eradication (secondary endpoint). Perihepatic lymph node enlargement was detected in 164 of 472 (34.7%) patients before DAA treatment. Surprisingly, disappearance of PLNE was observed in 23.8% (39 patients) of all PLNE-positive patients after eradication of HCV. Disappearance of PLNE was not associated with baseline clinical parameters or changing rates of clinical findings before and after DAA treatment. At baseline, presence of PLNE was significantly associated with a lower serum HCV-RNA level (P = .03), a higher serum AST level (P = .004) and a higher ALT level (P < .001) after adjustment for sex and age. In conclusion, PLNEs became undetectable after DAA treatment in 23.8% of PLNE-positive patients. Further study with a longer follow-up period is needed to clarify the clinical importance of this phenomenon especially in relationship with the risk of HCC development.
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Affiliation(s)
- H Hikita
- Department of Clinical Laboratory Medicine, Tokyo, Japan
| | - Masaya Sato
- Department of Clinical Laboratory Medicine, Tokyo, Japan.,Department of Gastroenterology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
| | - Momoe Endo
- Department of Clinical Laboratory Medicine, Tokyo, Japan
| | - Mamiko Sato
- Department of Clinical Laboratory Medicine, Tokyo, Japan
| | - Y Soroida
- Department of Clinical Laboratory Medicine, Tokyo, Japan
| | - T Kobayashi
- Department of Clinical Laboratory Medicine, Tokyo, Japan
| | - H Gotoh
- Department of Clinical Laboratory Medicine, Tokyo, Japan
| | - T Iwai
- Department of Clinical Laboratory Medicine, Tokyo, Japan
| | - R Nakagomi
- Department of Gastroenterology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
| | - R Tateishi
- Department of Gastroenterology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
| | - T Komuro
- Department of Clinical Laboratory Medicine, Tokyo, Japan
| | - S Sone
- Department of Clinical Laboratory Medicine, Tokyo, Japan
| | - K Koike
- Department of Gastroenterology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
| | - Y Yatomi
- Department of Clinical Laboratory Medicine, Tokyo, Japan
| | - H Ikeda
- Department of Clinical Laboratory Medicine, Tokyo, Japan
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19
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Zinna RA, Gotoh H, Kojima T, Niimi T. Recent advances in understanding the mechanisms of sexually dimorphic plasticity: insights from beetle weapons and future directions. Curr Opin Insect Sci 2018; 25:35-41. [PMID: 29602360 PMCID: PMC5880310 DOI: 10.1016/j.cois.2017.11.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 11/20/2017] [Accepted: 11/21/2017] [Indexed: 05/08/2023]
Abstract
Many traits that are sexually dimorphic, appearing either differently or uniquely in one sex, are also sensitive to an organism's condition. This phenomenon seems to have evolved to limit genetic conflict between traits that are under different selective pressures in each sex. Recent work has shed light on the molecular and developmental mechanisms that govern this condition sensitive growth, and this work has now expanded to encompass both sexual dimorphism as well as conditionally plastic growth, as it seems the two phenomena are linked on a molecular level. In all cases studied the gene doublesex, a conserved regulator of sex differentiation, controls both sexual dimorphism as well as the condition-dependent plastic responses common to these traits. However, the advent of next-generation -omics technologies has allowed researchers to decipher the common and diverged mechanisms of sexually dimorphic plasticity and expand investigations beyond the foundation laid by studies utilizing beetle weapons.
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Affiliation(s)
- Robert A Zinna
- Center for Insect Science, University of Arizona, Tucson, AZ 85721-0106, United States.
| | - Hiroki Gotoh
- Lab of Sericulture and Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
| | - Takaaki Kojima
- Department of Bioengineering Sciences, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
| | - Teruyuki Niimi
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, Nishigonaka 38, Myodaiji, Okazaki, 444-8585 Aichi, Japan
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20
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Hust J, Lavine MD, Worthington AM, Zinna R, Gotoh H, Niimi T, Lavine L. The Fat-Dachsous signaling pathway regulates growth of horns in Trypoxylus dichotomus, but does not affect horn allometry. J Insect Physiol 2018; 105:85-94. [PMID: 29366850 DOI: 10.1016/j.jinsphys.2018.01.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Revised: 01/19/2018] [Accepted: 01/19/2018] [Indexed: 06/07/2023]
Abstract
Males of the Asian rhinoceros beetle, Trypoxylus dichotomus, possess exaggerated head and thoracic horns that scale dramatically out of proportion to body size. While studies of insulin signaling suggest that this pathway regulates nutrition-dependent growth including exaggerated horns, what regulates disproportionate growth has yet to be identified. The Fat signaling pathway is a potential candidate for regulating disproportionate growth of sexually-selected traits, a hypothesis we advanced in a previous paper (Gotoh et al., 2015). To investigate the role of Fat signaling in the growth and scaling of the sexually dimorphic, condition-dependent traits of the in the Asian rhinoceros beetle T. dichotomus, we used RNA interference to knock down expression of fat and its co-receptor dachsous. Knockdown of fat, and to a lesser degree dachsous, caused shortening and widening of appendages, including the head and thoracic horns. However, scaling of horns to body size was not affected. Our results show that Fat signaling regulates horn growth in T. dichotomus as it does in appendage growth in other insects. However, we provide evidence that Fat signaling does not mediate the disproportionate, positive allometric growth of horns in T. dichotomus.
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Affiliation(s)
- James Hust
- Department of Entomology, Washington State University, Pullman, WA 99164, United States
| | - Mark D Lavine
- Department of Entomology, Washington State University, Pullman, WA 99164, United States
| | - Amy M Worthington
- Department of Entomology, Washington State University, Pullman, WA 99164, United States
| | - Robert Zinna
- Department of Entomology, Washington State University, Pullman, WA 99164, United States
| | - Hiroki Gotoh
- Department of Entomology, Washington State University, Pullman, WA 99164, United States; Lab of Sericulture and Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan
| | - T Niimi
- Lab of Sericulture and Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan; Division of Evolutionary Developmental Biology, National Institute for Basic Biology, Okazaki, Aichi 444-8585, Japan
| | - Laura Lavine
- Department of Entomology, Washington State University, Pullman, WA 99164, United States.
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21
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Gotoh H, Zinna RA, Ishikawa Y, Miyakawa H, Ishikawa A, Sugime Y, Emlen DJ, Lavine LC, Miura T. The function of appendage patterning genes in mandible development of the sexually dimorphic stag beetle. Dev Biol 2016; 422:24-32. [PMID: 27989519 DOI: 10.1016/j.ydbio.2016.12.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 12/07/2016] [Accepted: 12/07/2016] [Indexed: 11/30/2022]
Abstract
One of the defining features of the evolutionary success of insects is the morphological diversification of their appendages, especially mouthparts. Although most insects share a common mouthpart ground plan, there is remarkable diversity in the relative size and shapes of these appendages among different insect lineages. One of the most prominent examples of mouthpart modification can be found in the enlargement of mandibles in stag beetles (Coleoptera, Insecta). In order to understand the proximate mechanisms of mouthpart modification, we investigated the function of appendage-patterning genes in mandibular enlargement during extreme growth of the sexually dimorphic mandibles of the stag beetle Cyclommatus metallifer. Based on knowledge from Drosophila and Tribolium studies, we focused on seven appendage patterning genes (Distal-less (Dll), aristaless (al), dachshund (dac), homothorax (hth), Epidermal growth factor receptor (Egfr), escargot (esg), and Keren (Krn). In order to characterize the developmental function of these genes, we performed functional analyses by using RNA interference (RNAi). Importantly, we found that RNAi knockdown of dac resulted in a significant mandible size reduction in males but not in female mandibles. In addition to reducing the size of mandibles, dac knockdown also resulted in a loss of the serrate teeth structures on the mandibles of males and females. We found that al and hth play a significant role during morphogenesis of the large male-specific inner mandibular tooth. On the other hand, knockdown of the distal selector gene Dll did not affect mandible development, supporting the hypothesis that mandibles likely do not contain the distal-most region of the ancestral appendage and therefore co-option of Dll expression is unlikely to be involved in mandible enlargement in stag beetles. In addition to mandible development, we explored possible roles of these genes in controlling the divergent antennal morphology of Coleoptera.
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Affiliation(s)
- Hiroki Gotoh
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan; Department of Entomology, Washington State University, Pullman, WA 99164, USA; Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan.
| | - Robert A Zinna
- Department of Entomology, Washington State University, Pullman, WA 99164, USA
| | - Yuki Ishikawa
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan; Graduate School of Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Hitoshi Miyakawa
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan; Faculty of Agriculture, Utsunomiya University, Utsunomiya, Tochigi 321-8505, Japan
| | - Asano Ishikawa
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan; Division of Ecological Genetics, Department of Population Genetics, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
| | - Yasuhiro Sugime
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan
| | - Douglas J Emlen
- Division of Biological Sciences, University of Montana-Missoula, MT 59812, USA
| | - Laura C Lavine
- Department of Entomology, Washington State University, Pullman, WA 99164, USA
| | - Toru Miura
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan
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Gotoh H, Ishiguro M, Nishikawa H, Morita S, Okada K, Miyatake T, Yaginuma T, Niimi T. Molecular cloning and functional characterization of the sex-determination gene doublesex in the sexually dimorphic broad-horned beetle Gnatocerus cornutus (Coleoptera, Tenebrionidae). Sci Rep 2016; 6:29337. [PMID: 27404087 PMCID: PMC4941388 DOI: 10.1038/srep29337] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 06/13/2016] [Indexed: 11/08/2022] Open
Abstract
Various types of weapon traits found in insect order Coleoptera are known as outstanding examples of sexually selected exaggerated characters. It is known that the sex determination gene doublesex (dsx) plays a significant role in sex-specific expression of weapon traits in various beetles belonging to the superfamily Scarabaeoidea. Although sex-specific weapon traits have evolved independently in various Coleopteran groups, developmental mechanisms of sex-specific expression have not been studied outside of the Scarabaeoidea. In order to test the hypothesis that dsx-dependent sex-specific expression of weapon traits is a general mechanism among the Coleoptera, we have characterized the dsx in the sexually dimorphic broad-horned beetle Gnatocerus cornutus (Tenebrionidea, Tenebirionidae). By using molecular cloning, we identified five splicing variants of Gnatocerus cornutus dsx (Gcdsx), which are predicted to code four different isoforms. We found one male-specific variant (GcDsx-M), two female-specific variants (GcDsx-FL and GcDsx-FS) and two non-sex-specific variants (correspond to a single isoform, GcDsx-C). Knockdown of all Dsx isoforms resulted in intersex phenotype both in male and female. Also, knockdown of all female-specific isoforms transformed females to intersex phenotype, while did not affect male phenotype. Our results clearly illustrate the important function of Gcdsx in determining sex-specific trait expression in both sexes.
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Affiliation(s)
- Hiroki Gotoh
- Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan
| | - Mai Ishiguro
- Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan
| | - Hideto Nishikawa
- Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan
| | - Shinichi Morita
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38, Nishigonaka, Myodaiji, Okazaki 444-8585, Japan
| | - Kensuke Okada
- Graduate School of Environmental and Life Science, Okayama University, Okayama 700-8530, Japan
| | - Takahisa Miyatake
- Graduate School of Environmental and Life Science, Okayama University, Okayama 700-8530, Japan
| | - Toshinobu Yaginuma
- Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan
| | - Teruyuki Niimi
- Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38, Nishigonaka, Myodaiji, Okazaki 444-8585, Japan
- Department of Basic Biology, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), 38 Nishigonaka, Myodaiji, Okazaki 444-8585, Japan
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Zinna R, Gotoh H, Brent CS, Dolezal A, Kraus A, Niimi T, Emlen D, Lavine LC. Endocrine Control of Exaggerated Trait Growth in Rhinoceros Beetles. Integr Comp Biol 2016; 56:247-59. [PMID: 27252223 DOI: 10.1093/icb/icw042] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Juvenile hormone (JH) is a key insect growth regulator frequently involved in modulating phenotypically plastic traits such as caste determination in eusocial species, wing polymorphisms in aphids, and mandible size in stag beetles. The jaw morphology of stag beetles is sexually-dimorphic and condition-dependent; males have larger jaws than females and those developing under optimum conditions are larger in overall body size and have disproportionately larger jaws than males raised under poor conditions. We have previously shown that large males have higher JH titers than small males during development, and ectopic application of fenoxycarb (JH analog) to small males can induce mandibular growth similar to that of larger males. What remains unknown is whether JH regulates condition-dependent trait growth in other insects with extreme sexually selected structures. In this study, we tested the hypothesis that JH mediates the condition-dependent expression of the elaborate horns of the Asian rhinoceros beetle, Trypoxylus dichotomus. The sexually dimorphic head horn of this beetle is sensitive to nutritional state during larval development. Like stag beetles, male rhinoceros beetles receiving copious food produce disproportionately large horns for their body size compared with males under restricted diets. We show that JH titers are correlated with body size during the late feeding and early prepupal periods, but this correlation disappears by the late prepupal period, the period of maximum horn growth. While ectopic application of fenoxycarb during the third larval instar significantly delayed pupation, it had no effect on adult horn size relative to body size. Fenoxycarb application to late prepupae also had at most a marginal effect on relative horn size. We discuss our results in context of other endocrine signals of condition-dependent trait exaggeration and suggest that different beetle lineages may have co-opted different physiological signaling mechanisms to achieve heightened nutrient-sensitive weapon growth.
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Affiliation(s)
- R Zinna
- *Department of Entomology, Washington State University, Pullman, WA 99164 USA
| | - H Gotoh
- **Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - C S Brent
- U.S. Department of Agriculture, Arid-Land Agricultural Research Center, Maricopa, AZ 85138 USA
| | - A Dolezal
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA, 50011, USA
| | - A Kraus
- Department of Biology, Gonzaga University, Spokane, WA 99258 USA
| | - T Niimi
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, Okazaki, Aichi 444-8585, Japan
| | - D Emlen
- Division of Biological Sciences, University of Montana-Missoula, Missoula, MT 59812, USA
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Gotoh H, Zinna RA, Warren I, DeNieu M, Niimi T, Dworkin I, Emlen DJ, Miura T, Lavine LC. Identification and functional analyses of sex determination genes in the sexually dimorphic stag beetle Cyclommatus metallifer. BMC Genomics 2016; 17:250. [PMID: 27001106 PMCID: PMC4802893 DOI: 10.1186/s12864-016-2522-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Accepted: 02/24/2016] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Genes in the sex determination pathway are important regulators of sexually dimorphic animal traits, including the elaborate and exaggerated male ornaments and weapons of sexual selection. In this study, we identified and functionally analyzed members of the sex determination gene family in the golden metallic stag beetle Cyclommatus metallifer, which exhibits extreme differences in mandible size between males and females. RESULTS We constructed a C. metallifer transcriptomic database from larval and prepupal developmental stages and tissues of both males and females. Using Roche 454 pyrosequencing, we generated a de novo assembled database from a total of 1,223,516 raw reads, which resulted in 14,565 isotigs (putative transcript isoforms) contained in 10,794 isogroups (putative identified genes). We queried this database for C. metallifer conserved sex determination genes and identified 14 candidate sex determination pathway genes. We then characterized the roles of several of these genes in development of extreme sexual dimorphic traits in this species. We performed molecular expression analyses with RT-PCR and functional analyses using RNAi on three C. metallifer candidate genes--Sex-lethal (CmSxl), transformer-2 (Cmtra2), and intersex (Cmix). No differences in expression pattern were found between the sexes for any of these three genes. In the RNAi gene-knockdown experiments, we found that only the Cmix had any effect on sexually dimorphic morphology, and these mimicked the effects of Cmdsx knockdown in females. Knockdown of CmSxl had no measurable effects on stag beetle phenotype, while knockdown of Cmtra2 resulted in complete lethality at the prepupal period. These results indicate that the roles of CmSxl and Cmtra2 in the sex determination cascade are likely to have diverged in stag beetles when compared to Drosophila. Our results also suggest that Cmix has a conserved role in this pathway. In addition to those three genes, we also performed a more complete functional analysis of the C. metallifer dsx gene (Cmdsx) to identify the isoforms that regulate dimorphism more fully using exon-specific RNAi. We identified a total of 16 alternative splice variants of the Cmdsx gene that code for up to 14 separate exons. Despite the variation in RNA splice products of the Cmdsx gene, only four protein isoforms are predicted. The results of our exon-specific RNAi indicated that the essential CmDsx isoform for postembryonic male differentiation is CmDsxB, whereas postembryonic female specific differentiation is mainly regulated by CmDsxD. CONCLUSIONS Taken together, our results highlight the importance of studying the function of highly conserved sex determination pathways in numerous insect species, especially those with dramatic and exaggerated sexual dimorphism, because conservation in protein structure does not always translate into conservation in downstream function.
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Affiliation(s)
- Hiroki Gotoh
- Department of Entomology, Washington State University, Pullman, WA, 99164, USA
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, 060-0810, Japan
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi, 464-8601, Japan
| | - Robert A Zinna
- Department of Entomology, Washington State University, Pullman, WA, 99164, USA
| | - Ian Warren
- Department of Entomology, Washington State University, Pullman, WA, 99164, USA
| | - Michael DeNieu
- Department of Zoology, Michigan State University, East Lansing, MI, 48824, USA
| | - Teruyuki Niimi
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi, 464-8601, Japan
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, Okazaki, Aichi, 444-8585, Japan
| | - Ian Dworkin
- Department of Zoology, Michigan State University, East Lansing, MI, 48824, USA
- Department of Biology, McMaster University, Hamilton, ONT, L8S 4K1, Canada
| | - Douglas J Emlen
- Division of Biological Sciences, University of Montana-Missoula, Missoula, MT, 59812, USA
| | - Toru Miura
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, 060-0810, Japan
| | - Laura C Lavine
- Department of Entomology, Washington State University, Pullman, WA, 99164, USA.
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Kunihashi Y, Sanada H, Gotoh H, Onomitsu K, Kohda M, Nitta J, Sogawa T. Drift transport of helical spin coherence with tailored spin-orbit interactions. Nat Commun 2016; 7:10722. [PMID: 26952129 PMCID: PMC4786748 DOI: 10.1038/ncomms10722] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Accepted: 01/14/2016] [Indexed: 11/10/2022] Open
Abstract
Most future information processing techniques using electron spins in non-magnetic semiconductors will require both the manipulation and transfer of spins without their coherence being lost. The spin–orbit effective magnetic field induced by drifting electrons enables us to rotate the electron spins in the absence of an external magnetic field. However, the fluctuations in the effective magnetic field originating from the random scattering of electrons also cause undesirable spin decoherence, which limits the length scale of the spin transport. Here we demonstrate the drift transport of electron spins adjusted to a robust spin structure, namely a persistent spin helix. We find that the persistent spin helix enhances the spatial coherence of drifting spins, resulting in maximized spin decay length near the persistent spin helix condition. Within the enhanced distance of the spin transport, the transport path of electron spins can be modulated by employing time-varying in-plane voltages. Spin-orbit effects in non-magnetic semiconductors allow for the manipulation of electronic spins in the absence of an applied magnetic field. Here, the authors exploit a persistent spin helix state in single quantum wells to enhance the coherence length of electronic drift transport.
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Affiliation(s)
- Y Kunihashi
- NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi, Kanagawa 243-0198, Japan
| | - H Sanada
- NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi, Kanagawa 243-0198, Japan
| | - H Gotoh
- NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi, Kanagawa 243-0198, Japan
| | - K Onomitsu
- NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi, Kanagawa 243-0198, Japan
| | - M Kohda
- Department of Materials Science, Tohoku University, 6-6-02 Aramaki-Aza Aoba, Aoba-ku, Sendai 980-8579, Japan
| | - J Nitta
- Department of Materials Science, Tohoku University, 6-6-02 Aramaki-Aza Aoba, Aoba-ku, Sendai 980-8579, Japan
| | - T Sogawa
- NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi, Kanagawa 243-0198, Japan
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Mills MR, Nemri RS, Carlson EA, Wilde W, Gotoh H, Lavine LC, Swanson BO. Functional mechanics of beetle mandibles: Honest signaling in a sexually selected system. ACTA ACUST UNITED AC 2015; 325:3-12. [DOI: 10.1002/jez.1961] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Revised: 07/21/2015] [Accepted: 07/23/2015] [Indexed: 11/09/2022]
Affiliation(s)
- Maria R. Mills
- Department of BiologyGonzaga UniversitySpokaneWashington
| | - Rahmi S. Nemri
- Department of BiologyGonzaga UniversitySpokaneWashington
| | | | - William Wilde
- Department of BiologyGonzaga UniversitySpokaneWashington
| | - Hiroki Gotoh
- Department of EntomologyWashington State UniversityPullmanWashington
| | - Laura C. Lavine
- Department of EntomologyWashington State UniversityPullmanWashington
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Saiki R, Gotoh H, Toga K, Miura T, Maekawa K. High juvenile hormone titre and abdominal activation of JH signalling may induce reproduction of termite neotenics. Insect Mol Biol 2015; 24:432-441. [PMID: 25847681 DOI: 10.1111/imb.12169] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 01/30/2015] [Accepted: 02/03/2015] [Indexed: 06/04/2023]
Abstract
Termite castes are a key example of polyphenism, in which reproductive division of labour is clearly seen in colonies. The reproductive castes in termites include primary and neotenic reproductives; primary reproductives found a new colony whereas neotenics succeed them in the reproductive role when the primary reproductives die or become senescent. Neotenics usually differentiate from nymphs or workers by developing functional gonads while retaining juvenile characteristics; however, the developmental mechanism during neotenic differentiation remains poorly understood. Juvenile hormone (JH) mediates a number of aspects of developmental regulation in caste differentiation in termites. In the present study we quantified JH titres in neotenic reproductives of Reticulitermes speratus, and compared these with other developmental stages. In addition, expression changes in JH signalling gene homologues (Methoprene-tolerant [Met], Krüppel-homolog1, Broad-Complex) in the head, thorax and abdomen were investigated during neotenic differentiation. Finally, we examined the function of Met in reproduction of neotenics by RNA interference (RNAi). Our results showed that the JH titres of neotenics were significantly higher than those of nymphs and workers. JH signalling genes were highly expressed in neotenic abdomens, compared with those in workers and nymphs. Met RNAi resulted in the inhibition of vitellogenin gene expression in newly moulted neotenics. These results suggest that the fertility of neotenics might be controlled by a large increase of JH titres and body-part-specific activation of JH signalling pathways.
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Affiliation(s)
- R Saiki
- Department of Biology, Graduate School of Science and Engineering, University of Toyama, Toyama, 930-8555, 3190, Gofuku, Japan
| | - H Gotoh
- Department of Entomology, Washington State University, Pullman, WA, 99164, USA
- Laboratory of Ecological Genetics, Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, 060-0810, Japan
- Laboratory of Sericulture and Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi, 466-8550, Japan
| | - K Toga
- Department of Biology, Graduate School of Science and Engineering, University of Toyama, Toyama, 930-8555, 3190, Gofuku, Japan
- Laboratory of Sericulture and Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi, 466-8550, Japan
| | - T Miura
- Laboratory of Ecological Genetics, Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, 060-0810, Japan
| | - K Maekawa
- Department of Biology, Graduate School of Science and Engineering, University of Toyama, Toyama, 930-8555, 3190, Gofuku, Japan
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Gotoh H, Hust JA, Miura T, Niimi T, Emlen DJ, Lavine LC. The Fat/Hippo signaling pathway links within-disc morphogen patterning to whole-animal signals during phenotypically plastic growth in insects. Dev Dyn 2015; 244:1039-1045. [DOI: 10.1002/dvdy.24296] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 05/13/2015] [Accepted: 05/15/2015] [Indexed: 12/11/2022] Open
Affiliation(s)
- Hiroki Gotoh
- Graduate School of Bioagricultural Sciences, Nagoya University; Chikusa Nagoya Japan
| | - James A. Hust
- Department of Entomology; Washington State University; Pullman Washington
| | - Toru Miura
- Graduate School of Environmental Science, Hokkaido University; Sapporo Hokkaido Japan
| | - Teruyuki Niimi
- Graduate School of Bioagricultural Sciences, Nagoya University; Chikusa Nagoya Japan
| | - Douglas J. Emlen
- Division of Biological Sciences; University of Montana-Missoula; Montana
| | - Laura C. Lavine
- Department of Entomology; Washington State University; Pullman Washington
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Abstract
Animal structures occasionally attain extreme proportions, eclipsing in size the surrounding body parts. We review insect examples of exaggerated traits, such as the mandibles of stag beetles (Lucanidae), the claspers of praying mantids (Mantidae), the elongated hindlimbs of grasshoppers (Orthoptera: Caelifera), and the giant heads of soldier ants (Formicidae) and termites (Isoptera). Developmentally, disproportionate growth can arise through trait-specific modifications to the activity of at least four pathways: the sex determination pathway, the appendage patterning pathway, the insulin/IGF signaling pathway, and the juvenile hormone/ecdysteroid pathway. Although most exaggerated traits have not been studied mechanistically, it is already apparent that distinct developmental mechanisms underlie the evolution of the different types of exaggerated traits. We suggest this reflects the nature of selection in each instance, revealing an exciting link between mechanism, form, and function. We use this information to make explicit predictions for the types of regulatory pathways likely to underlie each type of exaggerated trait.
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Affiliation(s)
- Laura Lavine
- Department of Entomology, Washington State University, Pullman, Washington 99164; ,
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Wu M, Gotoh H, Waters T, Walsh DB, Lavine LC. Identification of an alternative knockdown resistance (kdr)-like mutation, M918L, and a novel mutation, V1010A, in the Thrips tabaci voltage-gated sodium channel gene. Pest Manag Sci 2014; 70:977-81. [PMID: 23983138 DOI: 10.1002/ps.3638] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Revised: 08/17/2013] [Accepted: 08/23/2013] [Indexed: 05/27/2023]
Abstract
BACKGROUND Knockdown resistance (kdr) has been identified as a main mechanism against pyrethroid insecticides in many arthropod pests including in the onion thrips, Thrips tabaci. To characterize and identify pyrethroid-resistance in onion thrips in Washington state, we conducted insecticide bioassays and sequenced a region of the voltage gated sodium channel gene from several different T. tabaci populations. RESULTS Field collected Thrips tabaci were found to have large variations in resistance to the pyrethroid insecticide lambda-cyhalothrin. We identified two single nucleotide substitutions in our analysis of a partial sequence of the T. tabaci voltage-gated sodium channel gene. One mutation resulted in the non-synonymous substitution of methionine with leucine (M918L), which is well known to be responsible for super knockdown resistance in some pest species. Another non-synonymous substitution, a valine (GTT) to alanine (GCT) replacement at amino acid 1010 (V1010A) was identified in our study and was associated with lambda-cyhalothrin resistance. CONCLUSION We have characterized a known kdr mutation and identified a novel mutation in the voltage-gated sodium channel gene of Thrips tabaci associated with resistance to lambda-cyhalothrin. This gene region and these mutations are expected to be useful in the development of a diagnostic test to detect kdr resistance in many onion thrips populations.
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Affiliation(s)
- Meixiang Wu
- College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, Fujian, P.R. China; Department of Entomology, Washington State University, Pullman, WA, USA
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31
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Johns A, Gotoh H, McCullough EL, Emlen DJ, Lavine LC. Heightened condition-dependent growth of sexually selected weapons in the rhinoceros beetle, Trypoxylus dichotomus (Coleoptera: Scarabaeidae). Integr Comp Biol 2014; 54:614-21. [PMID: 24827150 DOI: 10.1093/icb/icu041] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The exaggerated weapons and ornaments of sexual selection are condition-dependent traits that often grow to exaggerated proportions. The horns of male rhinoceros beetles are extremely sensitive to the larval nutritional environment and are used by rival males in combat over access to females. In contrast to horns, other parts of the body, such as wings, eyes, and legs, scale proportionally with body size, whereas others, such as males' external genitalia, are invariant with body size, regardless of nutrition. We document how body parts of the Asian rhinoceros beetle, Trypoxylus dichotomus, exhibit plasticity and constraint in response to nutritional condition. We discuss the implications of these results for the evolution of condition-dependent and condition-independent traits in animals.
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Affiliation(s)
- A Johns
- *Division of Biological Sciences, The University of Montana, 104 Health Science Building, Missoula, MT 59812, USA; Department of Entomology, Washington State University, Pullman, WA 99164-6382, USA
| | - H Gotoh
- *Division of Biological Sciences, The University of Montana, 104 Health Science Building, Missoula, MT 59812, USA; Department of Entomology, Washington State University, Pullman, WA 99164-6382, USA
| | - E L McCullough
- *Division of Biological Sciences, The University of Montana, 104 Health Science Building, Missoula, MT 59812, USA; Department of Entomology, Washington State University, Pullman, WA 99164-6382, USA
| | - D J Emlen
- *Division of Biological Sciences, The University of Montana, 104 Health Science Building, Missoula, MT 59812, USA; Department of Entomology, Washington State University, Pullman, WA 99164-6382, USA
| | - L C Lavine
- *Division of Biological Sciences, The University of Montana, 104 Health Science Building, Missoula, MT 59812, USA; Department of Entomology, Washington State University, Pullman, WA 99164-6382, USA
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Watanabe D, Gotoh H, Miura T, Maekawa K. Social interactions affecting caste development through physiological actions in termites. Front Physiol 2014; 5:127. [PMID: 24782780 PMCID: PMC3988372 DOI: 10.3389/fphys.2014.00127] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 03/14/2014] [Indexed: 11/13/2022] Open
Abstract
A colony of social insects is not only an aggregation of individuals but also a functional unit. To achieve adaptive social behavior in fluctuating environmental conditions, in addition to coordination of physiological status in each individual, the whole colony is coordinated by interactions among colony members. The study on the regulation of social-insect colonies is termed "social physiology." Termites, a major group of social insects, exhibit many interesting phenomena related to social physiology, such as mechanisms of caste regulation in a colony. In their colonies, there are different types of individuals, i.e., castes, which show distinctive phenotypes specialized in specific colony tasks. Termite castes comprise reproductives, soldiers and workers, and the caste composition can be altered depending on circumstances. For the regulation of caste compositions, interactions among individuals, i.e., social interactions, are thought to be important. In this article, we review previous studies on the adaptive meanings and those on the proximate mechanisms of the caste regulation in termites, and try to understand those comprehensively in terms of social physiology. Firstly, we summarize classical studies on the social interactions. Secondly, previous studies on the pheromone substances that mediate the caste regulatory mechanisms are overviewed. Then, we discuss the roles of a physiological factor, juvenile hormone (JH) in the regulation of caste differentiation. Finally, we introduce the achievements of molecular studies on the animal sociality (i.e., sociogenomics) in terms of social physiology. By comparing the proximate mechanisms of social physiology in termites with those in hymenopterans, we try to get insights into the general principles of social physiology in social animals.
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Affiliation(s)
- Dai Watanabe
- Laboratory of Ecological Genetics, Graduate School of Environmental Science, Hokkaido UniversitySapporo, Hokkaido, Japan
- Department of Biology, Graduate School of Science and Engineering, University of ToyamaToyama, Japan
| | - Hiroki Gotoh
- Laboratory of Ecological Genetics, Graduate School of Environmental Science, Hokkaido UniversitySapporo, Hokkaido, Japan
- Department of Entomology, Washington State UniversityPullman, WA, USA
| | - Toru Miura
- Laboratory of Ecological Genetics, Graduate School of Environmental Science, Hokkaido UniversitySapporo, Hokkaido, Japan
| | - Kiyoto Maekawa
- Department of Biology, Graduate School of Science and Engineering, University of ToyamaToyama, Japan
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Gotoh H, Miyakawa H, Ishikawa A, Ishikawa Y, Sugime Y, Emlen DJ, Lavine LC, Miura T. Developmental link between sex and nutrition; doublesex regulates sex-specific mandible growth via juvenile hormone signaling in stag beetles. PLoS Genet 2014; 10:e1004098. [PMID: 24453990 PMCID: PMC3894178 DOI: 10.1371/journal.pgen.1004098] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Accepted: 11/26/2013] [Indexed: 11/20/2022] Open
Abstract
Sexual dimorphisms in trait expression are widespread among animals and are especially pronounced in ornaments and weapons of sexual selection, which can attain exaggerated sizes. Expression of exaggerated traits is usually male-specific and nutrition sensitive. Consequently, the developmental mechanisms generating sexually dimorphic growth and nutrition-dependent phenotypic plasticity are each likely to regulate the expression of extreme structures. Yet we know little about how either of these mechanisms work, much less how they might interact with each other. We investigated the developmental mechanisms of sex-specific mandible growth in the stag beetle Cyclommatus metallifer, focusing on doublesex gene function and its interaction with juvenile hormone (JH) signaling. doublesex genes encode transcription factors that orchestrate male and female specific trait development, and JH acts as a mediator between nutrition and mandible growth. We found that the Cmdsx gene regulates sex differentiation in the stag beetle. Knockdown of Cmdsx by RNA-interference in both males and females produced intersex phenotypes, indicating a role for Cmdsx in sex-specific trait growth. By combining knockdown of Cmdsx with JH treatment, we showed that female-specific splice variants of Cmdsx contribute to the insensitivity of female mandibles to JH: knockdown of Cmdsx reversed this pattern, so that mandibles in knockdown females were stimulated to grow by JH treatment. In contrast, mandibles in knockdown males retained some sensitivity to JH, though mandibles in these individuals did not attain the full sizes of wild type males. We suggest that moderate JH sensitivity of mandibular cells may be the default developmental state for both sexes, with sex-specific Dsx protein decreasing sensitivity in females, and increasing it in males. This study is the first to demonstrate a causal link between the sex determination and JH signaling pathways, which clearly interact to determine the developmental fates and final sizes of nutrition-dependent secondary-sexual characters. Sexual dimorphisms such as the exaggerated antlers of deer, the enormous clawed chelae of crabs, and the horns and mandibles of beetles, are widespread across animal taxa and have fascinated biologists for centuries. Much recent work has uncovered the importance of the role of the sex-determination pathway in the expression of sexually dimorphic traits. However, critical interactions between this pathway and other growth regulatory mechanisms – for example, the physiological mechanisms involved in nutrition-dependent expression of these traits – are less well understood. In this study, we provide evidence of a developmental link between nutrition-sensitivity and sexual differentiation in the giant mandibles of the sexually dimorphic stag beetle, Cyclommatus metallifer. We examined the regulation and function of a key sex determination gene in animals, doublesex (dsx), and its interaction with juvenile hormone (JH), an important insect hormone known to regulate insect polyphenisms including the regulation of the disproportionate growth of male stag beetle mandibles. We found that Cmdsx changes mandibular responsiveness to JH in a sex-specific pattern. Based on these results, we hypothesize that sex-specific regulation of JH responsiveness is a developmental link between nutrition and sexual differentiation in stag beetles.
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Affiliation(s)
- Hiroki Gotoh
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, Japan
- Department of Entomology, Washington State University, Pullman, Washington, United States of America
| | - Hitoshi Miyakawa
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, Japan
- Okazaki Institute for Integrative Bioscience, National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, Japan
| | - Asano Ishikawa
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, Japan
- Ecological Genetics Laboratory, Center for Frontier Research, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Yuki Ishikawa
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, Japan
- Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Yasuhiro Sugime
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Douglas J. Emlen
- Division of Biological Sciences, The University of Montana-Missoula, Missoula, Montana, United States of America
| | - Laura C. Lavine
- Department of Entomology, Washington State University, Pullman, Washington, United States of America
| | - Toru Miura
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, Japan
- * E-mail:
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Abstract
Sexually-selected exaggerated traits tend to be unusually reliable signals of individual condition, as their expression tends to be more sensitive to nutritional history and physiological circumstance than that of other phenotypes. As such, these traits are the foundation for many models of sexual selection and animal communication, such as "handicap" and "good genes" models. Exactly how expression of these traits is linked to the bearer's condition has been a central yet unresolved question, in part because the underlying physiological mechanisms regulating their development have remained largely unknown. Recent discoveries across animals as diverse as deer, beetles, and flies now implicate the widely conserved insulin-like signaling pathway, as a common physiological mechanism regulating condition-sensitive structures with extreme growth. This raises the exciting possibility that one highly conserved pathway may underlie the evolution of trait exaggeration in a multitude of sexually-selected signal traits across the animal kingdom.
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Affiliation(s)
- Ian A Warren
- School of Biological Sciences, University of Bristol, UK
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Miyakawa H, Gotoh H, Sugimoto N, Miura T. Effect of juvenoids on predator-induced polyphenism in the water flea, Daphnia pulex. ACTA ACUST UNITED AC 2013; 319:440-50. [PMID: 23757335 DOI: 10.1002/jez.1807] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Revised: 04/22/2013] [Accepted: 05/06/2013] [Indexed: 11/10/2022]
Abstract
In Daphnia pulex, juveniles form "neckteeth" a defensive structure on their heads, in response to predatory kairomones released by Chaoborus larvae. This phenomenon provides a model experimental system for the study of developmental mechanisms and evolutionary processes in predator-induced polyphenisms. Although it is thought that kairomone signals are sensed and converted into physiological signals resulting in morphological changes, little is known about the endocrine and physiological mechanisms of this process. Juvenile hormones and related chemicals, that is, juvenoids, are key hormones responsible for various physiological events in insects, including polyphenisms. In some crustaceans, methyl farnesoate (MF) is known to act as a juvenoid. In order to investigate the functions of juvenoids in defense morph formation, we treated daphnids with MF as well as JHIII (Juvenile Hormone III, an insect juvenoid) and fenoxycarb (a synthetic juvenile hormone analog) during their developmental stages. Strikingly, in the first-instar juveniles, all examined juvenoids stimulated the formation of neckteeth only in the presence of kairomones, not by themselves. This juvenoid effect on the neckteeth formation might be due to disturbance of the JH pathway. Juvenoid treatments reduced tail-spine length, whereas predatory kairomones are known to elongate tail spine. These results suggest that other physiological factors are responsible for the tail-spine elongation.
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Affiliation(s)
- Hitoshi Miyakawa
- Laboratory of Ecological Genetics, Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, Japan; Okazaki Institute for Integrative Bioscience, National Institute for Basic Biology, National Institutes of Natural Sciences, Myodaiji, Okazaki, Aichi, Japan
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Griva K, Mooppil N, Pala Krishnan DS, McBain H, Newman SP, Tripepi G, Pannier B, Mallamaci F, London G, Zoccali C, Sood M, Manns B, Kappel J, Naimark D, Dart A, Komenda P, Rigatto C, Hiebert B, Tangri N, Perl J, Karaboyas A, Tentori F, Morgenstern H, Sen A, Rayner H, Vanholder R, Combe C, Hasegawa T, Mapes D, Robinson B, Pisoni R, Tentori F, Zepel L, Karaboyas A, Mendelssohn D, Ikizler T, Pisoni R, Fukuhara S, Gillespie B, Bieber B, Robinson B, Wilkie M, Karaboyas A, Rayner H, Fluck R, Morgenstern H, Li Y, Kerr P, Mendelssohn D, Wikstrom B, Tentori F, Pisoni R, Robinson B, Vanita Jassal S, Comment L, Karaboyas A, Bieber B, Morgenstern H, Sen A, De Sequera P, Marshall M, Fukuhara S, Robinson B, Pisoni R, Jin HM, Pan Y, Raimann JG, Etter M, Kooman J, Levin N, Marcelli D, Marelli C, van der Sande F, Thijssen S, Usvyat L, Kotanko P, Lu KC, Yang HY, Su SL, Palmer S, Saglimbene V, Ruospo M, Craig J, Celia E, Gelfman R, Stroumza P, Bednarek A, Dulawa J, Frazao J, Del Castillo D, Ecder T, Hegbrant J, Strippoli GFM, Hecking M, Bieber B, Ethier J, Kautzky-Willer A, Jadoul M, Saito A, Sunder-Plassmann G, Saemann M, Gillespie B, Horl W, Mariani L, Ramirez S, Pisoni R, Robinson B, Port F, Mallamaci F, Tripepi G, Leonardis D, Zoccali C, Fukuma S, Akizawa T, Akiba T, Saito A, Kurokawa K, Fukuhara S, Pannier B, Tripepi G, Mallamaci F, Zoccali C, London G, Stack AG, Casserly LF, Abdalla AA, Murthy BVR, Hegarty A, Cronin CJ, Hannigan A, Shaw C, Pitcher D, Sandford R, Spoto B, Pizzini P, Cutrupi S, D'Arrigo G, Tripepi G, Zoccali C, Mallamaci F, Ghalia K, Gubensek J, Arnol M, Ponikvar R, Buturovic-Ponikvar J, Palmer S, de Berardis G, Craig JC, Pellegrini F, Ruospo M, Tong A, Tonelli M, Hegbrant J, Strippoli GFM, Pizzini P, Torino C, Cutrupi S, Spoto B, D'Arrigo G, Tripepi R, Tripepi G, Zoccali C, Mallamaci F, von Gersdorff G, Usvyat L, Schaller M, Wong M, Thijssen S, Marcelli D, Barth C, Kotanko P, Torino C, D'Arrigo G, Postorino M, Tripepi G, Mallamaci F, Zoccali C, Chanouzas D, Ng KP, Baharani J, Endo M, Nakamura Y, Hara M, Murakami T, Tsukahara H, Watanabe Y, Matsuoka Y, Fujita K, Inoue M, Simizu T, Gotoh H, Goto Y, Delanaye P, Cavalier E, Moranne O, Krzesinski JM, Warling X, Smelten N, Pottel H, Schneider S, Malecki AK, Haller HG, Boenisch O, Kielstein JT, Movilli E, Camerini C, Gaggia P, Zubani R, Feller P, Poiatti P, Pola A, Carli O, Valzorio B, Possenti S, Bregoli L, Foini P, Cancarini G, Palmer S, Ruospo M, Natale P, Gargano L, Saglimbene V, Pellegrini F, Johnson DW, Craig JC, Hegbrant J, Strippoli GFM, Brunelli S, Krishnan M, Van Wyck D, Provenzano R, Goykhman I, Patel C, Nissenson A, De Mauri A, Conte MM, Chiarinotti D, David P, Capurro F, De Leo M, Postorino M, Marino C, Vilasi A, Tripepi G, Zoccali C, Dialysis C, Helps A, Edwards G, Mactier R, Coia J, Abe Y, Ito K, Ogahara S, Sasatomi Y, Saito T, Nakashima H, Jean-Charles C, Morgane V, Leila P, Carole S, Pierre-Louis C, Philippe Z, Jean-Francois T, Couchoud C, Dantony E, Guerrin MH, Villar E, Ecochard R, Nishi S, Goto S, Nakai K, Kono K, Yonekura Y, Ito J, Fujii H, Korkmaz S, Ersoy A, Gulten S, Ercan I, Koca N, Serdengecti K, Suleymanlar G, Altiparmak M, Seyahi N, Jager K, Trabulus S, Erek E, Cobo Jaramillo G, Gallar P, Di Gioia C, Rodriguez I, Ortega O, Herrero JC, Oliet A, Vigil A, Pechter U, Luman M, Ilmoja M, Sinimae E, Auerbach A, Lilienthal K, Kallaste M, Sepp K, Piel L, Seppet E, Muliin M, Telling K, Seppet E, Kolvald K, Veermae K, Ots-Rosenberg M, Ambrus C, Kerkovits L, Szegedi J, Benke A, Toth E, Nagy L, Borbas B, Rozinka A, Nemeth J, Varga G, Kulcsar I, Gergely L, Szakony S, Kiss I, Koo JR, Choi MJ, Yoon MH, Park JY, No EY, Seo JW, Lee YK, Noh JW. Epidemiology - CKD 5D II. Nephrol Dial Transplant 2013. [DOI: 10.1093/ndt/gft151] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Ishikawa A, Gotoh H, Abe T, Miura T. Juvenile hormone titer and wing-morph differentiation in the vetch aphid Megoura crassicauda. J Insect Physiol 2013; 59:444-449. [PMID: 23434762 DOI: 10.1016/j.jinsphys.2013.02.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Revised: 02/08/2013] [Accepted: 02/11/2013] [Indexed: 06/01/2023]
Abstract
Most aphids exhibit wing polyphenism, in which winged and wingless females are produced depending on aphid densities. Although juvenile hormone (JH) has been implicated in the regulation of aphid wing polyphenism, relatively few studies examining the direct relationship between JH titer and resultant wing morphs have been undertaken. We therefore investigated the relationship between JH III titer and the development of wing morphs in the vetch aphid Megoura crassicauda during postembryonic development. JH III measurements by liquid chromatography-mass spectrometry (LC-MS) revealed that, at the third instar, presumptive wingless nymphs had significantly higher JH III titers than winged nymphs. In winged nymphs at the third instar, JH III application inhibited wing development resulting in the appearance of winged/wingless intermediates as well as juvenilized individuals with supernumerary molting. These results suggest that JH III plays an important role in wing-morph differentiation during postembryonic development.
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Affiliation(s)
- Asano Ishikawa
- Laboratory of Ecological Genetics, Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan
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Oguri K, Tsunoi T, Kato K, Nakano H, Nishikawa T, Gotoh H, Tateno K, Sogawa T. Surface Carrier Dynamics on Semiconductor Studied with Femtosecond Core-Level Photoelectron Spectroscopy Using Extreme Ultraviolet High-Order Harmonic Source. EPJ Web of Conferences 2013. [DOI: 10.1051/epjconf/20134104017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Okada Y, Gotoh H, Miura T, Miyatake T, Okada K. Juvenile hormone mediates developmental integration between exaggerated traits and supportive traits in the horned flour beetle Gnatocerus cornutus. Evol Dev 2012; 14:363-71. [DOI: 10.1111/j.1525-142x.2012.00554.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Yasukazu Okada
- Laboratory of Evolutionary Ecology; Graduate School of Environmental Science; Okayama University; Tsushima-naka 1-1-1; Okayama; Japan
| | - Hiroki Gotoh
- Laboratory of Ecological Genetics; Graduate School of Environmental Science; Hokkaido University; N10 W5 Kita-ku; Sapporo; Japan
| | - Toru Miura
- Laboratory of Ecological Genetics; Graduate School of Environmental Science; Hokkaido University; N10 W5 Kita-ku; Sapporo; Japan
| | - Takahisa Miyatake
- Laboratory of Evolutionary Ecology; Graduate School of Environmental Science; Okayama University; Tsushima-naka 1-1-1; Okayama; Japan
| | - Kensuke Okada
- Laboratory of Evolutionary Ecology; Graduate School of Environmental Science; Okayama University; Tsushima-naka 1-1-1; Okayama; Japan
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Iseda K, Gotoh H, Takahashi K, Nakajima M. Lateral Drainage of Superficial Sylvian Vein into Sphenoparietal Sinus: A Risk Factor for Postoperative Sylvian Vein Thrombosis after Dolenc Procedure. Skull Base Surg 2012. [DOI: 10.1055/s-0032-1314092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Ishikawa A, Ogawa K, Gotoh H, Walsh TK, Tagu D, Brisson JA, Rispe C, Jaubert-Possamai S, Kanbe T, Tsubota T, Shiotsuki T, Miura T. Juvenile hormone titre and related gene expression during the change of reproductive modes in the pea aphid. Insect Mol Biol 2012; 21:49-60. [PMID: 21988597 DOI: 10.1111/j.1365-2583.2011.01111.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Most aphids show reproductive polyphenism, i.e. they alternate their reproductive modes from parthenogenesis to sexual reproduction in response to short photoperiods. Although juvenile hormone (JH) has been considered a likely candidate for regulating the transition from asexual to sexual reproduction after photoperiod sensing, there are few studies investigating the direct relationship between JH titres and the reproductive-mode change. In addition, the sequencing of the pea aphid genome has allowed identification of the genes involved in the JH pathway, which in turn allows us to examine their expression levels in relation to the reproductive-mode change. Using liquid chromatography-mass spectrometry in the pea aphid, JHIII titre was shown to be lower in aphids producing sexual morphs under short-day conditions than in aphids producing parthenogenetic morphs under long-day conditions. The expression levels of genes upstream and downstream of JH action were quantified by real-time quantitative reverse-transcription-PCR across the reproductive-mode change. The expression level of JH esterase, which is responsible for JH degradation, was significantly higher in aphids reared under short-day conditions. This suggests that the upregulation of the JH degradation pathway may be responsible for the lower JHIII titre in aphids exposed to short-days, leading to the production of sexual morphs.
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Affiliation(s)
- A Ishikawa
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Japan
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Gotoh H, Cornette R, Koshikawa S, Okada Y, Lavine LC, Emlen DJ, Miura T. Juvenile hormone regulates extreme mandible growth in male stag beetles. PLoS One 2011; 6:e21139. [PMID: 21731659 PMCID: PMC3120829 DOI: 10.1371/journal.pone.0021139] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Accepted: 05/20/2011] [Indexed: 11/19/2022] Open
Abstract
The morphological diversity of insects is one of the most striking phenomena in biology. Evolutionary modifications to the relative sizes of body parts, including the evolution of traits with exaggerated proportions, are responsible for a vast range of body forms. Remarkable examples of an insect trait with exaggerated proportions are the mandibular weapons of stag beetles. Male stag beetles possess extremely enlarged mandibles which they use in combat with rival males over females. As with other sexually selected traits, stag beetle mandibles vary widely in size among males, and this variable growth results from differential larval nutrition. However, the mechanisms responsible for coupling nutrition with growth of stag beetle mandibles (or indeed any insect structure) remain largely unknown. Here, we demonstrate that during the development of male stag beetles (Cyclommatus metallifer), juvenile hormone (JH) titers are correlated with the extreme growth of an exaggerated weapon of sexual selection. We then investigate the putative role of JH in the development of the nutritionally-dependent, phenotypically plastic mandibles, by increasing hemolymph titers of JH with application of the JH analog fenoxycarb during larval and prepupal developmental periods. Increased JH signaling during the early prepupal period increased the proportional size of body parts, and this was especially pronounced in male mandibles, enhancing the exaggerated size of this trait. The direction of this response is consistent with the measured JH titers during this same period. Combined, our results support a role for JH in the nutrition-dependent regulation of extreme mandible growth in this species. In addition, they illuminate mechanisms underlying the evolution of trait proportion, the most salient feature of the evolutionary diversification of the insects.
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Affiliation(s)
- Hiroki Gotoh
- Laboratory of Ecological Genetics, Graduate School of Environmental Science, Hokkaido University, Sapporo, Japan
| | - Richard Cornette
- Anhydrobiosis Research Unit, National Institute of Agrobiological Sciences, Tsukuba, Japan
| | - Shigeyuki Koshikawa
- Laboratory of Molecular Biology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Yasukazu Okada
- Laboratory of Evolutionary Ecology, Graduate School of Environmental Science, Okayama University, Okayama, Japan
| | - Laura Corley Lavine
- Department of Entomology, Washington State University, Pullman, Washington, United States of America
| | - Douglas J. Emlen
- Division of Biological Sciences, University of Montana-Missoula, Missoula, Montana, United States of America
| | - Toru Miura
- Laboratory of Ecological Genetics, Graduate School of Environmental Science, Hokkaido University, Sapporo, Japan
- * E-mail:
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Watanabe D, Gotoh H, Miura T, Maekawa K. Soldier presence suppresses presoldier differentiation through a rapid decrease of JH in the termite Reticulitermes speratus. J Insect Physiol 2011; 57:791-795. [PMID: 21414320 DOI: 10.1016/j.jinsphys.2011.03.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Revised: 03/03/2011] [Accepted: 03/07/2011] [Indexed: 05/30/2023]
Abstract
The regulation of caste differentiation is essential to insect eusociality. Termite soldiers are sterile and cannot eat by themselves because they have specialized mouth morphology. Almost all termite species have a soldier caste, and the soldier ratio per colony is maintained at a low level, probably by elaborate regulatory mechanisms. Although the soldier presence is considered to negatively affect soldier differentiation in all examined species, the detailed mechanism remains unclear. Presoldier differentiation can be induced artificially by juvenile hormone (JH) application to workers, showing that JH is a key factor underlying the regulation of soldier differentiation. In this study, to elucidate physiological changes in workers because of the soldier presence during the molt into presoldiers, JH III applications and JH titer quantifications were carried out in the rhinotermitid termite Reticulitermes speratus. Firstly, the effects of soldier presence before the molt into presoldiers induced by JH III application to workers were investigated. The rates of presoldier molt induced by the treatments with soldiers were significantly lower than those without soldiers. Secondly, worker JH titers in the presence or absence of soldiers were quantified by LC-MS on day 0, 5, 10, and 15 after JH application. Results indicated that the worker JH titers (endogenous+applied JH III) in the presence of soldiers were significantly lower than those without soldiers on day 5 after the JH treatment. On days 10 and 15, such soldier effects were not observed. Finally, the effective duration of soldier presence after the JH application was elucidated. A 4 day period of co-existence with soldiers suppressed presoldier differentiation, suggesting that the soldier presence rapidly decreased the JH titer in other colony members (i.e., workers), resulting in the inhibition of presoldier production.
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Affiliation(s)
- Dai Watanabe
- Graduate School of Science and Engineering, University of Toyama, Toyama, Japan
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Sanada H, Sogawa T, Gotoh H, Onomitsu K, Kohda M, Nitta J, Santos PV. Acoustically induced spin-orbit interactions revealed by two-dimensional imaging of spin transport in GaAs. Phys Rev Lett 2011; 106:216602. [PMID: 21699325 DOI: 10.1103/physrevlett.106.216602] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Indexed: 05/31/2023]
Abstract
Magneto-optic Kerr microscopy was employed to investigate the spin-orbit interactions of electrons traveling in semiconductor quantum wells using surface acoustic waves (SAWs). Two-dimensional images of the spin flow induced by SAWs exhibit anisotropic spin precession behaviors caused by the coexistence of different types of spin-orbit interactions. The dependence of spin-orbit effective magnetic fields on SAW intensity indicates the existence of acoustically controllable spin-orbit interactions resulting from the strain and Rashba contributions induced by the SAWs.
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Affiliation(s)
- H Sanada
- NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi, Kanagawa 243-0198, Japan.
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Abstract
Bacterial biofilm formation can be induced by antimicrobial and DNA damage agents. These agents trigger the SOS response, in which SOS sensor RecA stimulates auto-cleavage of repressor LexA. These observations lead to a hypothesis of a connection between stress-inducible biofilm formation and the RecA-LexA interplay. To test this hypothesis, three biofilm assays were conducted, viz. the standard 96-well assay, confocal laser scanning microscopy, and the newly developed biofilm-on-paper assay. It was found that biofilm stimulation by the DNA replication inhibitor hydroxyurea was dependent on RecA and appeared repressed by the non-cleavable LexA of Pseudomonas aeruginosa. Surprisingly, deletion of lexA led to reduction of both normal and stress-inducible biofilm formation, suggesting that the wild-type LexA contributes to biofilm formation. The decreases was not the result of poor growth of the mutants. These results suggest SOS involvement in hydroxyurea-inducible biofilm formation. In addition, with the paper biofilm assay, it was found that degradation of the biofilm matrix DNA by DNase I appeared to render the biofilms susceptible to the replication inhibitor. The puzzling questions concerning the roles of LexA in DNA release in the biofilm context are discussed.
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Affiliation(s)
- H Gotoh
- Department of Biology, The University of Texas at San Antonio, San Antonio, TX 78249, USA
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Gotoh H, Gohda T, Tanimoto M, Gotoh Y, Horikoshi S, Tomino Y. Contribution of subcutaneous fat accumulation to insulin resistance and atherosclerosis in haemodialysis patients. Nephrol Dial Transplant 2009; 24:3474-80. [DOI: 10.1093/ndt/gfp290] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Cornette R, Gotoh H, Koshikawa S, Miura T. Juvenile hormone titers and caste differentiation in the damp-wood termite Hodotermopsis sjostedti (Isoptera, Termopsidae). J Insect Physiol 2008; 54:922-930. [PMID: 18541259 DOI: 10.1016/j.jinsphys.2008.04.017] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2007] [Revised: 04/17/2008] [Accepted: 04/18/2008] [Indexed: 05/26/2023]
Abstract
Termites are social insects, presenting morphologically distinct castes, performing specific tasks in the colony. The developmental processes underlying caste differentiation are mainly controlled by juvenile hormone (JH). Although many fragmentary data support this fact, there was no comparative work on JH titers during the caste differentiation processes. In this study, JH titer variation was investigated using a liquid chromatography-mass spectrometry (LC-MS) quantification method in all castes of the Japanese damp-wood termite Hodotermopsis sjostedti, especially focusing on the soldier caste differentiation pathway, which was induced by treatment with a JH analog. Hemolymph JH titers fluctuated between 20 and 720pg/microl. A peak of JH was observed during molting events for the pseudergate stationary molt and presoldier differentiation, but this peak was absent prior to the imaginal molt. Soldier caste differentiation was generally associated with high JH titers and nymph to alate differentiation with low JH titers. However, JH titer rose in females during alate maturation, probably in relation to vitellogenesis. In comparison, JH titer was surprisingly low in neotenics. On the basis of these results in both natural and artificial conditions, the current model for JH action on termite caste differentiation is discussed and re-appraised.
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Affiliation(s)
- Richard Cornette
- Laboratory of Ecological Genetics, Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810, Japan
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Tawara T, Kamada H, Zhang YH, Tanabe T, Cade NI, Ding D, Johnson SR, Gotoh H, Kuramochi E, Notomi M, Sogawa T. Quality factor control and lasing characteristics of InAs/InGaAs quantum dots embedded in photonic-crystal nanocavities. Opt Express 2008; 16:5199-5205. [PMID: 18542622 DOI: 10.1364/oe.16.005199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We demonstrate lasing action with a high spontaneous emission factor and temperature insensitivity in InAs/InGaAs quantum dots (QD) embedded in photonic crystal nanocavities. A quality factor (Q) of over 10,000 was achieved by suppressing the material absorption by QDs uncoupled to the cavity mode. High Q cavities exhibited ultra low threshold lasing with a spontaneous emission factor of 0.7. Less frequent carrier escape from the QDs, which was primarily favored by high potential barrier energy, enabled low threshold lasing up to 90 K.
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Affiliation(s)
- T Tawara
- NTT Basic Research Laboratories, NTT Corporation, 3-1, Morinosato-Wakamiya, Atsugi, Kanagawa, 243-0198, Japan.
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Tawara T, Gotoh H, Akasaka T, Kobayashi N, Saitoh T. Cavity polaritons in InGaN microcavities at room temperature. Phys Rev Lett 2004; 92:256402. [PMID: 15245040 DOI: 10.1103/physrevlett.92.256402] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2003] [Indexed: 05/24/2023]
Abstract
Cavity polaritons are observed in InGaN quantum well (QW) microcavities at room temperature. High-quality microcavities are fabricated by the wafer-bonding of InGaN QW layers and dielectric distributed Bragg reflectors. The anticrossing behavior of strong exciton-photon coupling is confirmed by vacuum-field Rabi splitting obtained from reflection measurements. This strong coupling is also enhanced by increasing the integrated oscillator strength coupled to the cavity mode. The oscillator strength of InGaN QW excitons is 1 order of magnitude larger than that of GaAs QW excitons.
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Affiliation(s)
- T Tawara
- NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi, Kanagawa 243-0198, Japan.
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Nomura T, Nakajima H, Ryo H, Li LY, Fukudome Y, Adachi S, Gotoh H, Tanaka H. Transgenerational transmission of radiation- and chemically induced tumors and congenital anomalies in mice: studies of their possible relationship to induced chromosomal and molecular changes. Cytogenet Genome Res 2004; 104:252-60. [PMID: 15162048 DOI: 10.1159/000077499] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2003] [Accepted: 12/16/2003] [Indexed: 11/19/2022] Open
Abstract
This article provides a broad overview of our earlier studies on the induction of tumors and congenital anomalies in the progeny of X-irradiated or chemically treated mice and our subsequent (published, hitherto unpublished and on-going) investigations aimed at identifying potential relationships between genetic changes induced in germ cells and the adverse effects manifest as tumors and congenital anomalies using cytogenetic and molecular approaches. The earlier studies document the fact that tumors and congenital anomalies can be induced by irradiation or treatment with certain chemicals such as urethane and that these phenotypes are heritable i.e., transmitted to generations beyond the first generation. These findings support the view that transmissible induced genetic changes are involved. The induced rates of congenital abnormalities and tumors are about two orders of magnitude higher than those recorded in the literature from classical mutation studies with specific locus mutations. The cytogenetic studies addressed the question of whether there were any relationships between induced translocations and induced tumors. The available data permit the inference that gross chromosomal changes may not be involved but do not exclude smaller induced genetic changes that are beyond the resolution of the techniques used in these studies. Other work on possible relationship between visible chromosomal anomalies (in bone marrow preparations) and tumors were likewise negative. However, there were indications that some induced cytogenetic changes might underlie induced congenital anomalies, i.e., trisomies, deletions and inversions were observed in induced and transmissible congenital anomalies (such as dwarfs, tail anomalies). Studies that explored possible relationships between induction of minisatellite mutations at the Pc-3 locus and tumors were negative. However, gene expression analysis of tumor (hepatoma)-susceptible offspring of progeny descended from irradiated male mice showed abnormal expression of many genes. Of these, only very few were oncogenes. This lends some support to our hypothesis that cumulative changes in gene expression of many genes, which perform normal cellular functions, may contribute to the occurrence of tumors in the offspring of irradiated or chemically treated mice.
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MESH Headings
- 4-Nitroquinoline-1-oxide/toxicity
- Abnormalities, Drug-Induced/genetics
- Abnormalities, Radiation-Induced/genetics
- Animals
- Carcinogens/toxicity
- Chromosome Aberrations
- Chromosomes/drug effects
- Chromosomes/genetics
- Chromosomes/radiation effects
- Chromosomes/ultrastructure
- Female
- Gene Expression Profiling
- Genes, Lethal
- Germ Cells/drug effects
- Germ Cells/radiation effects
- Infectious Disease Transmission, Vertical
- Male
- Mice
- Mice, Inbred ICR
- Minisatellite Repeats/drug effects
- Neoplasms, Experimental/chemically induced
- Neoplasms, Experimental/etiology
- Neoplasms, Experimental/genetics
- Neoplasms, Radiation-Induced/etiology
- Neoplasms, Radiation-Induced/genetics
- Neoplastic Syndromes, Hereditary/chemically induced
- Neoplastic Syndromes, Hereditary/etiology
- Neoplastic Syndromes, Hereditary/genetics
- Oncogenes
- Polychlorinated Dibenzodioxins/toxicity
- Radiation Injuries, Experimental/genetics
- Translocation, Genetic
- Urethane/toxicity
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Affiliation(s)
- T Nomura
- Department of Radiation Biology and Medical Genetics, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan.
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