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Bast EM, Marshall NT, Myers KO, Marsh LW, Hurtado MW, Van Zandt PA, Lehnert MS. Diverse material properties and morphology of moth proboscises relates to the feeding habits of some macromoth and other lepidopteran lineages. Interface Focus 2024; 14:20230051. [PMID: 38618232 PMCID: PMC11008959 DOI: 10.1098/rsfs.2023.0051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Accepted: 01/03/2024] [Indexed: 04/16/2024] Open
Abstract
Insects have evolved unique structures that host a diversity of material and mechanical properties, and the mouthparts (proboscis) of butterflies and moths (Lepidoptera) are no exception. Here, we examined proboscis morphology and material properties from several previously unstudied moth lineages to determine if they relate to flower visiting and non-flower visiting feeding habits. Scanning electron microscopy and three-dimensional imaging were used to study proboscis morphology and assess surface roughness patterns on the galeal surface, respectively. Confocal laser scanning microscopy was used to study patterns of cuticular autofluorescence, which was quantified with colour analysis software. We found that moth proboscises display similar autofluorescent signals and morphological patterns in relation to feeding habits to those previously described for flower and non-flower visiting butterflies. The distal region of proboscises of non-flower visitors is brush-like for augmented capillarity and exhibited blue autofluorescence, indicating the possible presence of resilin and increased flexibility. Flower visitors have smoother proboscises and show red autofluorescence, an indicator of high sclerotization, which is adaptive for floral tube entry. We propose the lepidopteran proboscis as a model structure for understanding how insects have evolved a suite of morphological and material adaptations to overcome the challenges of acquiring fluids from diverse sources.
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Affiliation(s)
- Elaine M. Bast
- Department of Biological Sciences, Kent State University at Stark, North Canton, OH, USA
| | - Natalie T. Marshall
- Department of Biological Sciences, Kent State University at Stark, North Canton, OH, USA
| | - Kendall O. Myers
- Department of Biological Sciences, Kent State University at Stark, North Canton, OH, USA
| | - Lucas W. Marsh
- Department of Biological Sciences, Kent State University at Stark, North Canton, OH, USA
| | | | | | - Matthew S. Lehnert
- Department of Biological Sciences, Kent State University at Stark, North Canton, OH, USA
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2
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Sugiyama M, Ozawa T, Ohta K, Okada K, Niimi T, Yamaguchi K, Shigenobu S, Okada Y. Transcriptomic and functional screening of weapon formation genes implies significance of cell adhesion molecules and female-biased genes in broad-horned flour beetle. PLoS Genet 2023; 19:e1011069. [PMID: 38051754 PMCID: PMC10723671 DOI: 10.1371/journal.pgen.1011069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 12/15/2023] [Accepted: 11/15/2023] [Indexed: 12/07/2023] Open
Abstract
For understanding the evolutionary mechanism of sexually selected exaggerated traits, it is essential to uncover its molecular basis. By using broad-horned flour beetle that has male-specific exaggerated structures (mandibular horn, head horn and gena enlargement), we investigated the transcriptomic and functional characters of sex-biased genes. Comparative transcriptome of male vs. female prepupal heads elucidated 673 sex-biased genes. Counter-intuitively, majority of them were female-biased (584 genes), and GO enrichment analysis showed cell-adhesion molecules were frequently female-biased. This pattern motivated us to hypothesize that female-biased transcripts (i.e. the transcripts diminished in males) may play a role in outgrowth formation. Potentially, female-biased genes may act as suppressors of weapon structure. In order to test the functionality of female-biased genes, we performed RNAi-mediated functional screening for top 20 female-biased genes and 3 genes in the most enriched GO term (cell-cell adhesion, fat1/2/3, fat4 and dachsous). Knockdown of one transcription factor, zinc finger protein 608 (zfp608) resulted in the formation of male-like gena in females, supporting the outgrowth suppression function of this gene. Similarly, knockdown of fat4 induced rudimental, abnormal mandibular horn in female. fat1/2/3RNAi, fat4RNAi and dachsousRNAi males exhibited thick and/or short mandibular horns and legs. These cell adhesion molecules are known to regulate tissue growth direction and known to be involved in the weapon formation in Scarabaeoidea beetles. Functional evidence in phylogenetically distant broad-horned flour beetle suggest that cell adhesion genes are repeatedly deployed in the acquisition of outgrowth. In conclusion, this study clarified the overlooked functions of female-biased genes in weapon development.
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Affiliation(s)
- Miyu Sugiyama
- Department of Biological Sciences, Tokyo Metropolitan University, Hachioji, Tokyo, Japan
| | - Takane Ozawa
- Department of Life Sciences, The University of Tokyo, Komaba, Tokyo, Japan
| | - Kunihiro Ohta
- Department of Life Sciences, The University of Tokyo, Komaba, Tokyo, Japan
| | - Kensuke Okada
- Faculty of Environmental, Life, Natural Science and Technology, Okayama University, Tsushima-naka, Okayama, Japan
| | - Teruyuki Niimi
- National Institute for Basic Biology, Nishigonaka, Myodaiji, Okazaki, Japan
- Basic Biology Program, The Graduate University for Advanced Studies, SOKENDAI, Nishigonaka, Myodaiji, Okazaki, Japan
| | - Katsushi Yamaguchi
- National Institute for Basic Biology, Nishigonaka, Myodaiji, Okazaki, Japan
| | - Shuji Shigenobu
- National Institute for Basic Biology, Nishigonaka, Myodaiji, Okazaki, Japan
- Basic Biology Program, The Graduate University for Advanced Studies, SOKENDAI, Nishigonaka, Myodaiji, Okazaki, Japan
| | - Yasukazu Okada
- Department of Biological Sciences, Tokyo Metropolitan University, Hachioji, Tokyo, Japan
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3
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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). JOURNAL OF INSECT SCIENCE (ONLINE) 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] [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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Boudinot BE, Moosdorf OTD, Beutel RG, Richter A. Anatomy and evolution of the head of Dorylus helvolus (Formicidae: Dorylinae): Patterns of sex- and caste-limited traits in the sausagefly and the driver ant. J Morphol 2021; 282:1616-1658. [PMID: 34427942 DOI: 10.1002/jmor.21410] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 08/12/2021] [Accepted: 08/15/2021] [Indexed: 12/21/2022]
Abstract
Ants are highly polyphenic Hymenoptera, with at least three distinct adult forms in the vast majority of species. Their sexual dimorphism, however, is overlooked to the point of being a nearly forgotten phenomenon. Using a multimodal approach, we interrogate the near total head microanatomy of the male of Dorylus helvolus, the "sausagefly," and compare it with the conspecific or near-conspecific female castes, the "driver ants." We found that no specific features were shared uniquely between the workers and males to the exclusion of the queens, indicating independence of male and worker development; males and queens, however, uniquely shared several features. Certain previous generalizations about ant sexual dimorphism are confirmed, while we also discover discrete muscular presences and absences, for which reason we provide a coarse characterization of functional morphology. Based on the unexpected retention of a medial carinate line on the structurally simplified mandible of the male, we postulate a series of developmental processes to explain the patterning of ant mandibles. We invoke functional and anatomical principles to classify sensilla. Critically, we observe an inversion of the expected pattern of male-queen mandible development: male Dorylus mandibles are extremely large while queen mandibles are poorly developed. To explain this, we posit that the reproductive-limited mandible phenotype is canalized in Dorylus, thus partially decoupling the queen and worker castes. We discuss alternative hypotheses and provide further comparisons to understand mandibular evolution in army ants. Furthermore, we hypothesize that the expression of the falcate phenotype in the queen is coincidental, that is, a "spandrel," and that the form of male mandibles is also generally coincidental across the ants. We conclude that the theory of ant development and evolution is incomplete without consideration of the male system, and we call for focused study of male anatomy and morphogenesis, and of trait limitation across all castes.
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Affiliation(s)
- Brendon Elias Boudinot
- Friedrich-Schiller-Universität Jena, Institut für Spezielle Zoologie und Evolutionsforschung, Entomology Group, Erbertstraße, Jena, Germany
| | - Olivia Tikuma Diana Moosdorf
- Friedrich-Schiller-Universität Jena, Institut für Spezielle Zoologie und Evolutionsforschung, Entomology Group, Erbertstraße, Jena, Germany
| | - Rolf Georg Beutel
- Friedrich-Schiller-Universität Jena, Institut für Spezielle Zoologie und Evolutionsforschung, Entomology Group, Erbertstraße, Jena, Germany
| | - Adrian Richter
- Friedrich-Schiller-Universität Jena, Institut für Spezielle Zoologie und Evolutionsforschung, Entomology Group, Erbertstraße, Jena, Germany
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5
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Schartl M, Kneitz S, Ormanns J, Schmidt C, Anderson JL, Amores A, Catchen J, Wilson C, Geiger D, Du K, Garcia-Olazábal M, Sudaram S, Winkler C, Hedrich R, Warren WC, Walter R, Meyer A, Postlethwait JH. The Developmental and Genetic Architecture of the Sexually Selected Male Ornament of Swordtails. Curr Biol 2021; 31:911-922.e4. [PMID: 33275891 PMCID: PMC8580132 DOI: 10.1016/j.cub.2020.11.028] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 10/12/2020] [Accepted: 11/11/2020] [Indexed: 12/21/2022]
Abstract
Sexual selection results in sex-specific characters like the conspicuously pigmented extension of the ventral tip of the caudal fin-the "sword"-in males of several species of Xiphophorus fishes. To uncover the genetic architecture underlying sword formation and to identify genes that are associated with its development, we characterized the sword transcriptional profile and combined it with genetic mapping approaches. Results showed that the male ornament of swordtails develops from a sexually non-dimorphic prepattern of transcription factors in the caudal fin. Among genes that constitute the exclusive sword transcriptome and are located in the genomic region associated with this trait we identify the potassium channel, Kcnh8, as a sword development gene. In addition to its neural function kcnh8 performs a known role in fin growth. These findings indicate that during evolution of swordtails a brain gene has been co-opted for an additional novel function in establishing a male ornament.
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Affiliation(s)
- Manfred Schartl
- Developmental Biochemistry, Biocenter, University of Wuerzburg, Am Hubland, 97074 Wuerzburg, Germany; The Xiphophorus Genetic Stock Center, Department of Chemistry and Biochemistry, Texas State University, San Marcos, TX 78666, USA.
| | - Susanne Kneitz
- Biochemistry and Cell Biology, Biocenter, University of Wuerzburg, Am Hubland, 97074 Wuerzburg, Germany
| | - Jenny Ormanns
- Biochemistry and Cell Biology, Biocenter, University of Wuerzburg, Am Hubland, 97074 Wuerzburg, Germany
| | - Cornelia Schmidt
- Biochemistry and Cell Biology, Biocenter, University of Wuerzburg, Am Hubland, 97074 Wuerzburg, Germany
| | - Jennifer L Anderson
- Systematic Biology, Department of Organismal Biology, Uppsala University, Norbyvägen 18D, 752 36 Uppsala, Sweden
| | - Angel Amores
- Institute of Neuroscience, University of Oregon, Eugene, OR 97401, USA
| | - Julian Catchen
- Department of Animal Biology, University of Illinois, Urbana, IL 6812, USA
| | - Catherine Wilson
- Institute of Neuroscience, University of Oregon, Eugene, OR 97401, USA
| | - Dietmar Geiger
- Julius-von-Sachs-Institute for Biosciences, Molecular Plant Physiology and Biophysics, Biocenter, University Würzburg, Julius-von-Sachs-Platz 2, 97082 Würzburg, Germany
| | - Kang Du
- Developmental Biochemistry, Biocenter, University of Wuerzburg, Am Hubland, 97074 Wuerzburg, Germany; The Xiphophorus Genetic Stock Center, Department of Chemistry and Biochemistry, Texas State University, San Marcos, TX 78666, USA
| | | | - Sudha Sudaram
- Department of Biological Sciences and Centre for Bioimaging Sciences, National University of Singapore, Singapore 117543, Singapore
| | - Christoph Winkler
- Department of Biological Sciences and Centre for Bioimaging Sciences, National University of Singapore, Singapore 117543, Singapore
| | - Rainer Hedrich
- Julius-von-Sachs-Institute for Biosciences, Molecular Plant Physiology and Biophysics, Biocenter, University Würzburg, Julius-von-Sachs-Platz 2, 97082 Würzburg, Germany
| | - Wesley C Warren
- 440G Bond Life Sciences Center, 1201 Rollins Street, University of Missouri, Columbia, MO 65211, USA
| | - Ronald Walter
- The Xiphophorus Genetic Stock Center, Department of Chemistry and Biochemistry, Texas State University, San Marcos, TX 78666, USA
| | - Axel Meyer
- Lehrstuhl für Zoologie und Evolutionsbiologie, Department of Biology, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany.
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6
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Haug JT, Schädel M, Baranov VA, Haug C. An unusual 100-million-year old holometabolan larva with a piercing mouth cone. PeerJ 2020; 8:e8661. [PMID: 32280565 PMCID: PMC7134054 DOI: 10.7717/peerj.8661] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Accepted: 01/29/2020] [Indexed: 12/29/2022] Open
Abstract
Holometabola is a hyperdiverse group characterised by a strong morphological differentiation between early post-embryonic stages (= larvae) and adults. Adult forms of Holometabola, such as wasps, bees, beetles, butterflies, mosquitoes or flies, are strongly differentiated concerning their mouth parts. The larvae most often seem to retain rather plesiomorphic-appearing cutting-grinding mouth parts. Here we report a new unusual larva preserved in Burmese amber. Its mouth parts appear beak-like, forming a distinct piercing mouth cone. Such a morphology is extremely rare among larval forms, restricted to those of some beetles and lacewings. The mouth parts of the new fossil are forward oriented (prognathous). Additionally, the larva has distinct subdivisions of tergites and sternites into several sclerites. Also, the abdomen segments bear prominent protrusions. We discuss this unusual combination of characters in comparison to the many different types of holometabolan larvae. The here reported larva is a new addition to the 'unusual zoo' of the Cretaceous fauna including numerous, very unusual appearing forms that have gone extinct at the Cretaceous-Palaeogene boundary.
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Affiliation(s)
- Joachim T. Haug
- Department of Biology II, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
- GeoBio-Center at LMU, München, Germany
| | - Mario Schädel
- Department of Biology II, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Viktor A. Baranov
- Department of Biology II, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Carolin Haug
- Department of Biology II, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
- GeoBio-Center at LMU, München, Germany
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7
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Fujisawa T, Sasabe M, Nagata N, Takami Y, Sota T. Genetic basis of species-specific genitalia reveals role in species diversification. SCIENCE ADVANCES 2019; 5:eaav9939. [PMID: 31249868 PMCID: PMC6594765 DOI: 10.1126/sciadv.aav9939] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Accepted: 05/22/2019] [Indexed: 06/09/2023]
Abstract
The diversity of genital morphology among closely related animals with internal fertilization is well known, but the genetic backgrounds are unclear. Here, we show that, in Carabus (Ohomopterus) beetles showing correlated evolution of male and female genital parts, only a few major quantitative trait loci (QTLs) determine differences in genital dimensions between sister species, and sequence divergence is pronounced in the genomic regions containing genital QTLs. The major QTLs for male and female genital dimensions reside in different locations within the same linkage group, implying that coevolution between the sexes is only loosely constrained and can respond to sexually antagonistic selection. The same genomic regions containing the major QTLs show elevated divergence between three pairs of parapatric species with marked differences in genital parts. Our study demonstrates that species diversification can follow coevolution of genitalia between the sexes, even without tight linkage of loci affecting male and female genital dimensions.
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Affiliation(s)
- Tomochika Fujisawa
- Department of Zoology, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8502, Japan
| | - Masataka Sasabe
- Department of Zoology, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8502, Japan
| | - Nobuaki Nagata
- Division of Collections Conservation, National Museum of Nature and Science, Tsukuba 305-0005, Japan
| | - Yasuoki Takami
- Graduate School of Human Development and Environment, Kobe University, Kobe 657-8501, Japan
| | - Teiji Sota
- Department of Zoology, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8502, Japan
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8
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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] [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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9
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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] [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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