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Hu Y, Crabtree JR, Macagno ALM, Moczek AP. Histone deacetylases regulate organ-specific growth in a horned beetle. EvoDevo 2024; 15:4. [PMID: 38575982 PMCID: PMC10996171 DOI: 10.1186/s13227-024-00223-5] [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: 01/16/2024] [Accepted: 03/21/2024] [Indexed: 04/06/2024] Open
Abstract
BACKGROUND Nutrient availability is among the most widespread means by which environmental variability affects developmental outcomes. Because almost all cells within an individual organism share the same genome, structure-specific growth responses must result from changes in gene regulation. Earlier work suggested that histone deacetylases (HDACs) may serve as epigenetic regulators linking nutritional conditions to trait-specific development. Here we expand on this work by assessing the function of diverse HDACs in the structure-specific growth of both sex-shared and sex-specific traits including evolutionarily novel structures in the horned dung beetle Onthophagus taurus. RESULTS We identified five HDAC members whose downregulation yielded highly variable mortality depending on which HDAC member was targeted. We then show that HDAC1, 3, and 4 operate in both a gene- and trait-specific manner in the regulation of nutrition-responsiveness of appendage size and shape. Specifically, HDAC 1, 3, or 4 knockdown diminished wing size similarly while leg development was differentially affected by RNAi targeting HDAC3 and HDAC4. In addition, depletion of HDAC3 transcript resulted in a more rounded shape of genitalia at the pupal stage and decreased the length of adult aedeagus across all body sizes. Most importantly, we find that HDAC3 and HDAC4 pattern the morphology and regulate the scaling of evolutionarily novel head and thoracic horns as a function of nutritional variation. CONCLUSION Collectively, our results suggest that both functional overlap and division of labor among HDAC members contribute to morphological diversification of both conventional and recently evolved appendages. More generally, our work raises the possibility that HDAC-mediated scaling relationships and their evolution may underpin morphological diversification within and across insect species broadly.
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Affiliation(s)
- Yonggang Hu
- Department of Biology, Indiana University, 915 East 3rd Street, Bloomington, IN, 47405, USA.
- State Key Laboratory of Resource Insects, Institute of Sericulture and Systems Biology, Southwest University, No.2 Tiansheng Road, Beibei District, Chongqing, 400715, China.
| | - Jordan R Crabtree
- Department of Biology, Indiana University, 915 East 3rd Street, Bloomington, IN, 47405, USA
| | - Anna L M Macagno
- Department of Biology, Indiana University, 915 East 3rd Street, Bloomington, IN, 47405, USA
- Biostatistics Consulting Center, Department of Epidemiology and Biostatistics, School of Public Health Bloomington, Indiana University, 2719 E. 10th Street, Bloomington, IN, 47405, USA
| | - Armin P Moczek
- Department of Biology, Indiana University, 915 East 3rd Street, Bloomington, IN, 47405, USA
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2
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Bell MA, Lim G, Caldwell C, Emlen DJ, Swanson BO. Rhinoceros beetle (Trypoxylus dichotomus) cuticular hydrocarbons contain information about body size and sex. PLoS One 2024; 19:e0299796. [PMID: 38483942 PMCID: PMC10939270 DOI: 10.1371/journal.pone.0299796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Accepted: 02/15/2024] [Indexed: 03/17/2024] Open
Abstract
Japanese rhinoceros beetle (Trypoxylus dichotomus) males have exaggerated horns that are used to compete for territories. Larger males with larger horns tend to win these competitions, giving them access to females. Agonistic interactions include what appears to be assessment and often end without escalating to physical combat. However, it is unknown what information competitors use to assess each other. In many insect species chemical signals can carry a range of information, including social position, nutritional state, morphology, and sex. Specifically, cuticular hydrocarbons (CHCs), which are waxes excreted on the surface of insect exoskeletons, can communicate a variety of information. Here, we asked whether CHCs in rhinoceros beetles carry information about sex, body size, and condition that could be used by males during assessment behavior. Multivariate analysis of hydrocarbon composition revealed patterns associated with both sex and body size. We suggest that Rhinoceros beetles could be communicating information through CHCs that would explain behavioral decisions.
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Affiliation(s)
- Micah A. Bell
- Department of Biology, Gonzaga University, Spokane, Washington, United States of America
| | - Garrett Lim
- Department of Biology, Gonzaga University, Spokane, Washington, United States of America
| | - Chelsey Caldwell
- Division of Biological Sciences, The University of Montana, Missoula, Montana, United States of America
| | - Douglas J. Emlen
- Division of Biological Sciences, The University of Montana, Missoula, Montana, United States of America
| | - Brook O. Swanson
- Department of Biology, Gonzaga University, Spokane, Washington, United States of America
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3
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Fujiwara K, Miyazaki S, Maekawa K. Candidate target genes of the male-specific expressed Doublesex in the termite Reticulitermes speratus. PLoS One 2024; 19:e0299900. [PMID: 38427681 PMCID: PMC10906832 DOI: 10.1371/journal.pone.0299900] [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: 11/09/2023] [Accepted: 02/17/2024] [Indexed: 03/03/2024] Open
Abstract
Eusocial insects such as termites, ants, bees, and wasps exhibit a reproductive division of labor. The developmental regulation of reproductive organ (ovaries and testes) is crucial for distinguishing between reproductive and sterile castes. The development of reproductive organ in insects is regulated by sex-determination pathways. The sex determination gene Doublesex (Dsx), encoding transcription factors, plays an important role in this pathway. Therefore, clarifying the function of Dsx in the developmental regulation of sexual traits is important to understand the social evolution of eusocial insects. However, no studies have reported the function of Dsx in hemimetabolous eusocial group termites. In this study, we searched for binding sites and candidate target genes of Dsx in species with available genome information as the first step in clarifying the function of Dsx in termites. First, we focused on the Reticulitermes speratus genome and identified 101 candidate target genes of Dsx. Using a similar method, we obtained 112, 39, and 76 candidate Dsx target genes in Reticulitermes lucifugus, Coptotermes formosanus, and Macrotermes natalensis, respectively. Second, we compared the candidate Dsx target genes between species and identified 37 common genes between R. speratus and R. lucifugus. These included several genes probably involved in spermatogenesis and longevity. However, only a few common target genes were identified between R. speratus and the other two species. Finally, Dsx dsRNA injection resulted in the differential expression of several target genes, including piwi-like protein and B-box type zinc finger protein ncl-1 in R. speratus. These results provide valuable resource data for future functional analyses of Dsx in termites.
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Affiliation(s)
- Kokuto Fujiwara
- Graduate School of Science and Engineering, University of Toyama, Gofuku, Toyama, Japan
| | - Satoshi Miyazaki
- Graduate School of Agriculture, Tamagawa University, Machida, Tokyo, Japan
| | - Kiyoto Maekawa
- Academic Assembly, University of Toyama, Gofuku, Toyama, Japan
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4
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Rohner PT, Hu Y, Moczek AP. Utilizing geometric morphometrics to investigate gene function during organ growth: Insights through the study of beetle horn shape allometry. Evol Dev 2024; 26:e12464. [PMID: 38041612 DOI: 10.1111/ede.12464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 10/05/2023] [Accepted: 11/15/2023] [Indexed: 12/03/2023]
Abstract
Static allometry is a major component of morphological variation. Much of the literature on the development of allometry investigates how functional perturbations of diverse pathways affect the relationship between trait size and body size. Often, this is done with the explicit objective to identify developmental mechanisms that enable the sensing of organ size and the regulation of relative growth. However, changes in relative trait size can also be brought about by a range of other distinctly different developmental processes, such as changes in patterning or tissue folding, yet standard univariate biometric approaches are usually unable to distinguish among alternative explanations. Here, we utilize geometric morphometrics to investigate the degree to which functional genetic manipulations known to affect the size of dung beetle horns also recapitulate the effect of horn shape allometry. We reasoned that the knockdown phenotypes of pathways governing relative growth should closely resemble shape variation induced by natural allometric variation. In contrast, we predicted that if genes primarily affect alternative developmental processes, knockdown effects should align poorly with shape allometry. We find that the knockdown effects of several genes (e.g., doublesex, Foxo) indeed closely aligned with shape allometry, indicating that their corresponding pathways may indeed function primarily in the regulation of relative trait growth. In contrast, other knockdown effects (e.g., Distal-less, dachs) failed to align with allometry, implicating these pathways in potentially scaling-independent processes. Our findings moderate the interpretation of studies focusing on trait length and highlight the usefulness of multivariate approaches to study allometry and phenotypic plasticity.
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Affiliation(s)
- Patrick T Rohner
- Department of Biology, Indiana University, Bloomington, Indiana, USA
- Department of Ecology, Behavior, and Evolution, University of California San Diego, La Jolla, California, USA
| | - Yonggang Hu
- Department of Biology, Indiana University, Bloomington, Indiana, USA
- State Key Laboratory of Silkworm Genome Biology, Institute of Sericulture and Systems Biology, Southwest University, Chongqing, China
| | - Armin P Moczek
- Department of Biology, Indiana University, Bloomington, Indiana, USA
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5
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Davidson PL, Nadolski EM, Moczek AP. Gene regulatory networks underlying the development and evolution of plasticity in horned beetles. CURRENT OPINION IN INSECT SCIENCE 2023; 60:101114. [PMID: 37709168 PMCID: PMC10866377 DOI: 10.1016/j.cois.2023.101114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 08/17/2023] [Accepted: 09/07/2023] [Indexed: 09/16/2023]
Abstract
Horned beetles have emerged as a powerful study system with which to investigate the developmental mechanisms underlying environment-responsive development and its evolution. We begin by reviewing key advances in our understanding of the diverse roles played by transcription factors, endocrine regulators, and signal transduction pathways in the regulation of horned beetle plasticity. We then explore recent efforts aimed at understanding how such condition-specific expression may be regulated in the first place, as well as how the differential expression of master regulators may instruct conditional expression of downstream target genes. Here, we focus on the significance of chromatin remodeling as a powerful but thus far understudied mechanism able to facilitate trait-, sex-, and species-specific responses to environmental conditions.
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Affiliation(s)
- Phillip L Davidson
- Department of Biology, Indiana University Bloomington, IN 47405-7107, United States
| | - Erica M Nadolski
- Department of Biology, Indiana University Bloomington, IN 47405-7107, United States
| | - Armin P Moczek
- Department of Biology, Indiana University Bloomington, IN 47405-7107, United States.
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6
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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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7
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Price PD, Parkus SM, Wright AE. Recent progress in understanding the genomic architecture of sexual conflict. Curr Opin Genet Dev 2023; 80:102047. [PMID: 37163877 DOI: 10.1016/j.gde.2023.102047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/02/2023] [Accepted: 04/02/2023] [Indexed: 05/12/2023]
Abstract
Genomic conflict between the sexes over shared traits is widely assumed to be resolved through the evolution of sex-biased expression and the subsequent emergence of sexually dimorphic phenotypes. However, while there is support for a broad relationship between genome-wide patterns of expression level and sexual conflict, recent studies suggest that sex differences in the nature and strength of interactions between loci are instead key to conflict resolution. Furthermore, the advent of new technologies for measuring and perturbing expression means we now have much more power to detect genomic signatures of sexual conflict. Here, we review our current understanding of the genomic architecture of sexual conflict in the light of these new studies and highlight the potential for novel approaches to address outstanding knowledge gaps.
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Affiliation(s)
- Peter D Price
- Ecology and Evolutionary Biology, School of Biosciences, University of Sheffield, United Kingdom. https://twitter.com/@PeterDPrice
| | - Sylvie M Parkus
- Ecology and Evolutionary Biology, School of Biosciences, University of Sheffield, United Kingdom
| | - Alison E Wright
- Ecology and Evolutionary Biology, School of Biosciences, University of Sheffield, United Kingdom.
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8
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Wee JLQ, Murugesan SN, Wheat CW, Monteiro A. The genetic basis of wing spots in Pieris canidia butterflies. BMC Genomics 2023; 24:169. [PMID: 37016295 PMCID: PMC10074818 DOI: 10.1186/s12864-023-09261-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 03/20/2023] [Indexed: 04/06/2023] Open
Abstract
Spots in pierid butterflies and eyespots in nymphalid butterflies are likely non-homologous wing colour pattern elements, yet they share a few features in common. Both develop black scales that depend on the function of the gene spalt, and both might have central signalling cells. This suggests that both pattern elements may be sharing common genetic circuitry. Hundreds of genes have already been associated with the development of nymphalid butterfly eyespot patterns, but the genetic basis of the simpler spot patterns on the wings of pierid butterflies has not been investigated. To facilitate studies of pierid wing patterns, we report a high-quality draft genome assembly for Pieris canidia, the Indian cabbage white. We then conducted transcriptomic analyses of pupal wing tissues sampled from the spot and non-spot regions of P. canidia at 3-6 h post-pupation. A total of 1352 genes were differentially regulated between wing tissues with and without the black spot, including spalt, Krüppel-like factor 10, genes from the Toll, Notch, TGF-β, and FGFR signalling pathways, and several genes involved in the melanin biosynthetic pathway. We identified 14 genes that are up-regulated in both pierid spots and nymphalid eyespots and propose that spots and eyespots share regulatory modules despite their likely independent origins.
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Affiliation(s)
- Jocelyn Liang Qi Wee
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore.
| | - Suriya Narayanan Murugesan
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore.
| | | | - Antónia Monteiro
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore
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9
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Laslo M, Just J, Angelini DR. Theme and variation in the evolution of insect sex determination. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART B, MOLECULAR AND DEVELOPMENTAL EVOLUTION 2023; 340:162-181. [PMID: 35239250 PMCID: PMC10078687 DOI: 10.1002/jez.b.23125] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Revised: 11/24/2021] [Accepted: 01/03/2022] [Indexed: 11/07/2022]
Abstract
The development of dimorphic adult sexes is a critical process for most animals, one that is subject to intense selection. Work in vertebrate and insect model species has revealed that sex determination mechanisms vary widely among animal groups. However, this variation is not uniform, with a limited number of conserved factors. Therefore, sex determination offers an excellent context to consider themes and variations in gene network evolution. Here we review the literature describing sex determination in diverse insects. We have screened public genomic sequence databases for orthologs and duplicates of 25 genes involved in insect sex determination, identifying patterns of presence and absence. These genes and a 3.5 reference set of 43 others were used to infer phylogenies and compared to accepted organismal relationships to examine patterns of congruence and divergence. The function of candidate genes for roles in sex determination (virilizer, female-lethal-2-d, transformer-2) and sex chromosome dosage compensation (male specific lethal-1, msl-2, msl-3) were tested using RNA interference in the milkweed bug, Oncopeltus fasciatus. None of these candidate genes exhibited conserved roles in these processes. Amidst this variation we wish to highlight the following themes for the evolution of sex determination: (1) Unique features within taxa influence network evolution. (2) Their position in the network influences a component's evolution. Our analyses also suggest an inverse association of protein sequence conservation with functional conservation.
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Affiliation(s)
- Mara Laslo
- Department of Cell Biology, Curriculum Fellows ProgramHarvard Medical School25 Shattuck StBostonMassachusettsUSA
| | - Josefine Just
- Department of Organismic and Evolutionary BiologyHarvard University26 Oxford StCambridgeMassachusettsUSA
- Department of BiologyColby College5734 Mayflower Hill DrWatervilleMaineUSA
| | - David R. Angelini
- Department of BiologyColby College5734 Mayflower Hill DrWatervilleMaineUSA
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10
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Zhu XL, Yuan JJ, Zhou LY, Bartolozzi L, Wan X. Molecular phylogeny and historical biogeography of Cyclommatus stag beetles (Coleoptera: Lucanidae): Insights into their evolution and diversification in tropical and subtropical Asia. Front Ecol Evol 2023. [DOI: 10.3389/fevo.2023.974315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
Abstract
Cyclommatus stag beetles (Coleoptera, Lucanidae) are very interesting insects, because of their striking allometry (mandibles can be longer that the whole body in large males of some species) and sexual dimorphism. They mainly inhabit tropical and subtropical forests in Asia. To date, there has been no molecular phylogenetic research on how these stag beetles evolved and diversified. In this study, we constructed the first phylogenetic relationship for Cyclommatus using multi-locus datasets. Analyses showed that Cyclommatus is monophyletic, being subdivided into two well-supported clades (A and B). The clade A includes the island species from Southeast Asia, and the clade B is formed by the continental species. The divergent time estimates showed these beetles split from the outgroup around 43.10 million years ago (Mya) in the late Eocene, divided during the late Oligocene (around 24.90 Mya) and diversified further during the early and middle Miocene (around 18.19 Mya, around 15.17 Mya). RASP analysis suggested that these beetles likely originated in the Philippine archipelago, then dispersed to the other Southeast Asian archipelagoes, Indochina Peninsula, Southeast Himalayas, and Southern China. Moreover, relatively large genetic distance and stable morphological variations signified that the two clades reach the level of inter-generic differences, i.e., the current Cyclommatus should be separated in two genera: Cyclommatus Parry, 1863 including the clade A species, and Cyclommatinus Didier, 1927 covering the clade B species. In addition, the evidence we generated indicated these beetles’ diversification was promoted probably by both long-distance dispersal and colonization, supporting an “Upstream” colonization hypothesis. Our study provides insights into the classification, genetics and evolution of stag beetles in the Oriental region.
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11
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Roithmair Z, Edgecombe GD, Wanninger A, Akkari N. Sexually dimorphic characters of the ultimate legs in lithobiid centipedes (Myriapoda, Chilopoda, and Lithobiomorpha): Morphology and implications for reproductive behavior. J Morphol 2023; 284:e21549. [PMID: 36538584 DOI: 10.1002/jmor.21549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 11/29/2022] [Accepted: 12/10/2022] [Indexed: 12/24/2022]
Abstract
Many species of lithobiomorph centipedes present a pronounced sexual dimorphism reflected in remarkable structural modifications on the ultimate legs of males. Most records of these male secondary sexual characters addressed taxonomy, helping to identify and characterize species or diagnose genera, but information on their diversity, detailed morphology and possible function(s) is scarce. In this study, nine species of the two lithobiid genera Lithobius Leach, 1814 and Eupolybothrus Verhoeff, 1907 were investigated, using light and scanning electron microscopy to document the detailed morphology of secondary sexual characters of male ultimate legs. Secondary sexual characters affecting the cuticle of the ultimate legs are described in detail and found to often be associated with sensilla, interpreted here as chemo- and mechanoreceptors, and with clusters of pores, a hitherto undescribed pore-distribution for this group. The tibial nodule of the species Lithobius nodulipes Latzel, 1880, was additionally examined with histological semi-thin sections. These results revealed that the clustered pores are connected to glandular tissue, and are, based on their morphology, interpreted as openings of flexo-canal epidermal glands. The presence of various sensory and glandular structures associated with sexual dimorphism indicates a likely role during courtship and mating. The closely related species examined in this research show comparable dimorphic structures, which are otherwise species-specific. Morphological observations on secondary sexual structures inform on reproductive biology in groups like lithobiomorphs for which there are limited behavioral data.
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Affiliation(s)
- Zita Roithmair
- Department of Invertebrate Zoology III, Natural History Museum Vienna, Vienna, Austria.,Department of Evolutionary Biology, Unit for Integrative Zoology, Vienna, Austria
| | | | - Andreas Wanninger
- Department of Evolutionary Biology, Unit for Integrative Zoology, Vienna, Austria
| | - Nesrine Akkari
- Department of Invertebrate Zoology III, Natural History Museum Vienna, Vienna, Austria
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12
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CRISPR/Cas9-Mediated Mutagenesis of Sex-Specific Doublesex Splicing Variants Leads to Sterility in Spodoptera frugiperda, a Global Invasive Pest. Cells 2022; 11:cells11223557. [PMID: 36428986 PMCID: PMC9688123 DOI: 10.3390/cells11223557] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 11/06/2022] [Accepted: 11/08/2022] [Indexed: 11/12/2022] Open
Abstract
Spodoptera frugiperda (J. E. Smith), an emerging invasive pest worldwide, has posed a serious agricultural threat to the newly invaded areas. Although somatic sex differentiation is fundamentally conserved among insects, the sex determination cascade in S. frugiperda is largely unknown. In this study, we cloned and functionally characterized Doublesex (dsx), a "molecular switch" modulating sexual dimorphism in S. frugiperda using male- and female-specific isoforms. Given that Lepidoptera is recalcitrant to RNAi, CRISPR/Cas9-mediated mutagenesis was employed to construct S. frugiperda mutants. Specifically, we designed target sites on exons 2, 4, and 5 to eliminate the common, female-specific, and male-specific regions of S. frugiperda dsx (Sfdsx), respectively. As expected, abnormal development of both the external and internal genitalia was observed during the pupal and adult stages. Interestingly, knocking out sex-specific dsx variants in S. frugiperda led to significantly reduced fecundity and fertility in adults of corresponding sex. Our combined results not only confirm the conserved function of dsx in S. frugiperda sex differentiation but also provide empirical evidence for dsx as a potential target for the Sterile Insect Technique (SIT) to combat this globally invasive pest in a sustainable and environmentally friendly way.
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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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Otomo Y, Shinji J, Kohtsuka H, Miura T. Ontogenetic Expressions of Sexually Dimorphic Traits in the Skeleton Shrimp Caprella scaura (Crustacea: Amphipoda). Zoolog Sci 2022; 39:431-445. [DOI: 10.2108/zs220038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Accepted: 05/23/2022] [Indexed: 11/17/2022]
Affiliation(s)
- Yohei Otomo
- Misaki Marine Biological Station, School of Science, The University of Tokyo, Misaki, Miura, Kanagawa 238-0225, Japan
| | - Junpei Shinji
- Misaki Marine Biological Station, School of Science, The University of Tokyo, Misaki, Miura, Kanagawa 238-0225, Japan
| | - Hisanori Kohtsuka
- Misaki Marine Biological Station, School of Science, The University of Tokyo, Misaki, Miura, Kanagawa 238-0225, Japan
| | - Toru Miura
- Misaki Marine Biological Station, School of Science, The University of Tokyo, Misaki, Miura, Kanagawa 238-0225, Japan
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15
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Malacrinò A, Brengdahl MI, Kimber CM, Mital A, Shenoi VN, Mirabello C, Friberg U. Ageing desexualizes the Drosophila brain transcriptome. Proc Biol Sci 2022; 289:20221115. [PMID: 35946149 PMCID: PMC9364003 DOI: 10.1098/rspb.2022.1115] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
General evolutionary theory predicts that individuals in low condition should invest less in sexual traits compared to individuals in high condition. Whether this positive association between condition and investment also holds between young (high condition) and senesced (low condition) individuals is however less clear, since elevated investment into reproduction may be beneficial when individuals approach the end of their life. To address how investment into sexual traits changes with age, we study genes with sex-biased expression in the brain, the tissue from which sexual behaviours are directed. Across two distinct populations of Drosophila melanogaster, we find that old brains display fewer sex-biased genes, and that expression of both male-biased and female-biased genes converges towards a sexually intermediate phenotype owing to changes in both sexes with age. We further find that sex-biased genes in general show heightened age-dependent expression in comparison to unbiased genes and that age-related changes in the sexual brain transcriptome are commonly larger in males than females. Our results hence show that ageing causes a desexualization of the fruit fly brain transcriptome and that this change mirrors the general prediction that low condition individuals should invest less in sexual phenotypes.
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Affiliation(s)
- Antonino Malacrinò
- Institute for Evolution and Biodiversity, Westfälische Wilhelms-Universität Münster, Münster, Germany,Department of Agriculture, Università degli Studi Mediterranea di Reggio Calabria, Reggio Calabria, Italy
| | | | | | - Avani Mital
- IFM Biology, Linköping University, 581 83 Linköping, Sweden
| | | | - Claudio Mirabello
- Department of Physics, Chemistry and Biology, National Bioinformatics Infrastructure Sweden, Science for Life Laboratory, Linköping University, 581 83 Linköping, Sweden
| | - Urban Friberg
- IFM Biology, Linköping University, 581 83 Linköping, Sweden
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16
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Bai Y, Pei XJ, Ban N, Chen N, Liu SN, Li S, Liu TX. Nutrition-dependent juvenile hormone sensitivity promotes flight-muscle degeneration during the aphid dispersal-reproduction transition. Development 2022; 149:275958. [DOI: 10.1242/dev.200891] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 06/28/2022] [Indexed: 11/20/2022]
Abstract
ABSTRACT
In insects, the loss of flight typically involves a dispersal-reproduction transition, but the underlying molecular mechanisms remain poorly understood. In the parthenogenetic pea aphid Acyrthosiphon pisum, winged females undergo flight-muscle degeneration after flight and feeding on new host plants. Similarly, topical application of a juvenile hormone (JH) mimic to starved aphids also induces flight-muscle degeneration. We found that feeding preferentially upregulated the expression of the JH receptor gene Met and a JH-inducible gene, Kr-h1, in the flight muscles, and, thus, enhanced tissue-specific JH sensitivity and signaling. RNAi-mediated knockdown of Kr-h1 prevented flight-muscle degeneration. Likewise, blocking nutritional signals by pharmacological inhibition of the target of rapamycin complex 1 (TORC1) impaired JH sensitivity of the flight muscles in feeding aphids and subsequently delayed muscle degeneration. RNA-sequencing analysis revealed that enhanced JH signaling inhibited the transcription of genes involved in the tricarboxylic acid cycle, likely resulting in reduction of the energy supply, mitochondrial dysfunction and muscle-fiber breakdown. This study shows that nutrient-dependent hormone sensitivity regulates developmental plasticity in a tissue-specific manner, emphasizing a relatively underappreciated mechanism of hormone sensitivity in modulating hormone signaling.
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Affiliation(s)
- Yu Bai
- Guangdong Provincial Key Laboratory of Insect Development Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University 1 , Guangzhou 510631 , China
- State Key Laboratory of Crop Stress Biology for Arid Areas and Key Laboratory of Integrated Pest Management on the Loess Plateau of Ministry of Agriculture, Northwest A&F University 2 , Yangling 712100 , China
| | - Xiao-Jin Pei
- Guangdong Provincial Key Laboratory of Insect Development Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University 1 , Guangzhou 510631 , China
| | - Ning Ban
- Key Lab of Integrated Crop Pest Management of Shandong Province, College of Plant Health and Medicine, Qingdao Agricultural University 3 , Qingdao 266109 , China
| | - Nan Chen
- Guangdong Provincial Key Laboratory of Insect Development Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University 1 , Guangzhou 510631 , China
| | - Su-Ning Liu
- Guangdong Provincial Key Laboratory of Insect Development Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University 1 , Guangzhou 510631 , China
| | - Sheng Li
- Guangdong Provincial Key Laboratory of Insect Development Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University 1 , Guangzhou 510631 , China
| | - Tong-Xian Liu
- Institute of Entomology, Guizhou University 4 , Guiyang 550025 , China
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17
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Komata S, Lin CP, Fujiwara H. doublesex Controls Both Hindwing and Abdominal Mimicry Traits in the Female-Limited Batesian Mimicry of Papilio memnon. FRONTIERS IN INSECT SCIENCE 2022; 2:929518. [PMID: 38468762 PMCID: PMC10926503 DOI: 10.3389/finsc.2022.929518] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 06/20/2022] [Indexed: 03/13/2024]
Abstract
Papilio butterflies are known to possess female-limited Batesian mimicry polymorphisms. In Papilio memnon, females have mimetic and non-mimetic forms, whereas males are monomorphic and non-mimetic. Mimetic females are characterized by color patterns and tails in the hindwing and yellow abdomens. Recently, an analysis of whole-genome sequences has shown that an approximately 160 kb region of chromosome 25 is responsible for mimicry and has high diversity between mimetic (A) and non-mimetic (a) alleles (highly diversified region: HDR). The HDR includes three genes, UXT, doublesex (dsx), and Nach-like, but the functions of these genes are unknown. Here, we investigated the function of dsx, a gene involved in sexual differentiation, which is expected to be functionally important for hindwing and abdominal mimetic traits in P. memnon. Expression analysis by reverse transcription quantitative PCR (RT-qPCR) and RNA sequencing showed that mimetic dsx (dsx-A) was highly expressed in the hindwings in the early pupal stage. In the abdomen, both dsx-A and dsx-a were highly expressed during the early pupal stage. When dsx was knocked down using small interfering RNAs (siRNAs) designed in the common region of dsx-A and dsx-a, a male-like pattern appeared on the hindwings of mimetic and non-mimetic females. Similarly, when dsx was knocked down in the abdomen, the yellow scales characteristic of mimetic females changed to black. Furthermore, when dsx-a was specifically knocked down, the color pattern of the hindwings changed, as in the case of dsx knockdown in non-mimetic females but not mimetic females. These results suggest that dsx-a is involved in color pattern formation on the hindwings of non-mimetic females, whereas dsx-A is involved in hindwing and abdominal mimetic traits. dsx was involved in abdominal and hindwing mimetic traits, but dsx expression patterns in the hindwing and abdomen were different, suggesting that different regulatory mechanisms may exist. Our study is the first to show that the same gene (dsx) regulates both the hindwing and abdominal mimetic traits. This is the first functional analysis of abdominal mimicry in butterflies.
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Affiliation(s)
- Shinya Komata
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
| | - Chung-Ping Lin
- Department of Life Science, National Taiwan Normal University, Taipei, Taiwan
| | - Haruhiko Fujiwara
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
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18
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Ranian K, Kashif Zahoor M, Zulhussnain M, Ahmad A. CRISPR/Cas9 mediated sex-ratio distortion by sex specific gene editing in Aedes aegypti. Saudi J Biol Sci 2022; 29:3015-3022. [PMID: 35531165 PMCID: PMC9073027 DOI: 10.1016/j.sjbs.2022.01.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 01/05/2022] [Accepted: 01/13/2022] [Indexed: 10/26/2022] Open
Abstract
Aedes aegypti is a principal vector for several viruses including dengue virus, chikungunya virus and zika virus. Economic burden of mosquito-borne diseases, relative failure of traditional control strategies and the resistance development against insecticides enforces towards genetic manipulation of Ae. aegypti. Hence, a key gene doublesex (Aedsx) which regulate sex differentiation and alternatively splices to form male and female specific transcripts (AedsxM and AedsxF ). CRISPR/Cas9 technique was employed to sex specifically disrupt the female-specific isoforms, AedsxF1 and AedsxF2 , both of which were shown to be expressed only in female mosquitoes. Targeting of dsxF at the developmental stage has resulted in various phenotypic anomalies of adult females. The rate of adult mutation phenotype was recorded between 29 and 37% along with anomalies of wing size, proboscis length and reduction in the sizes of pre-blood-meal and after blood-meal ovaries in dsxF1 and dsxF2 microinjected groups, respectively. These findings can be correlated with reduced fecundity rate of Go female, where AedsxF1 and AedsxF2 groups showed reduction rate in range of 23-31%. Furthermore, hatching inhibition rate of 28 to 36% was also observed in G1 generation when compared to the wildtype. Overall, these results demonstrated that AedsxF disruption has resulted in multiple female traits disruption including decreased fertility of the female that could directly or indirectly associated with reproduction and its disease transmitting abilities. All these findings suggesting that CRISPR works to alter the developmental pathways as predicted, and therefore this method potentially gives us the basis for the sex-ratio distortion system as genetic control approach for the management of this vector.
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Affiliation(s)
- Kanwal Ranian
- Department of Zoology, Government College University Faisalabad, Pakistan
| | | | | | - Aftab Ahmad
- Centre of Department of Biochemistry/US-Pakistan Center for Advance Studies in Agriculture and Food Security (USPCAS-AFS), University of Agriculture Faisalabad, Pakistan
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19
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Wang Y, Rensink AH, Fricke U, Riddle MC, Trent C, van de Zande L, Verhulst EC. Doublesex regulates male-specific differentiation during distinct developmental time windows in a parasitoid wasp. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2022; 142:103724. [PMID: 35093500 DOI: 10.1016/j.ibmb.2022.103724] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 01/19/2022] [Accepted: 01/19/2022] [Indexed: 06/14/2023]
Abstract
Sexually dimorphic traits in insects are subject to sexual selection, but our knowledge of the underlying molecular mechanisms is still scarce. Here we investigate how the highly conserved gene, Doublesex (Dsx), is involved in shaping sexual dimorphism in the model parasitoid wasp Nasonia vitripennis (Hymenoptera: Pteromalidae). First, we present the revised Dsx gene structure including an alternative transcription start, and two additional male NvDsx transcript isoforms. We show sex-specific NvDsx expression and splicing throughout development, and demonstrate that transient NvDsx silencing in different male developmental stages shifts two sexually dimorphic traits from male to female morphology, with the effect being dependent on the timing of silencing. In addition, we determined the effect of NvDsx on the development of reproductive organs. Transient silencing of NvDsx in early male larvae affects the growth and differentiation of the internal and external reproductive tissues. We did not observe phenotypic changes in females after NvDsx silencing. Our results indicate that male NvDsx is required to suppress female-specific traits and/or to promote male-specific traits during distinct developmental windows. This provides new insights into the regulatory activity of Dsx during male wasp development in the Hymenoptera.
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Affiliation(s)
- Yidong Wang
- Wageningen University, Laboratory of Entomology, Wageningen, the Netherlands
| | - Anna H Rensink
- Evolutionary Genetics, Development and Behaviour, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, the Netherlands
| | - Ute Fricke
- Wageningen University, Laboratory of Entomology, Wageningen, the Netherlands
| | - Megan C Riddle
- Biology Department, Western Washington University, Washington, USA
| | - Carol Trent
- Biology Department, Western Washington University, Washington, USA
| | - Louis van de Zande
- Evolutionary Genetics, Development and Behaviour, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, the Netherlands
| | - Eveline C Verhulst
- Wageningen University, Laboratory of Entomology, Wageningen, the Netherlands; Wageningen University, Laboratory of Genetics, Wageningen, the Netherlands.
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20
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Suzuki Y, Toh L. Constraints and Opportunities for the Evolution of Metamorphic Organisms in a Changing Climate. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.734031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We argue that developmental hormones facilitate the evolution of novel phenotypic innovations and timing of life history events by genetic accommodation. Within an individual’s life cycle, metamorphic hormones respond readily to environmental conditions and alter adult phenotypes. Across generations, the many effects of hormones can bias and at times constrain the evolution of traits during metamorphosis; yet, hormonal systems can overcome constraints through shifts in timing of, and acquisition of tissue specific responses to, endocrine regulation. Because of these actions of hormones, metamorphic hormones can shape the evolution of metamorphic organisms. We present a model called a developmental goblet, which provides a visual representation of how metamorphic organisms might evolve. In addition, because developmental hormones often respond to environmental changes, we discuss how endocrine regulation of postembryonic development may impact how organisms evolve in response to climate change. Thus, we propose that developmental hormones may provide a mechanistic link between climate change and organismal adaptation.
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21
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Goodwin SF, Hobert O. Molecular Mechanisms of Sexually Dimorphic Nervous System Patterning in Flies and Worms. Annu Rev Cell Dev Biol 2021; 37:519-547. [PMID: 34613817 DOI: 10.1146/annurev-cellbio-120319-115237] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Male and female brains display anatomical and functional differences. Such differences are observed in species across the animal kingdom, including humans, but have been particularly well-studied in two classic animal model systems, the fruit fly Drosophila melanogaster and the nematode Caenorhabditis elegans. Here we summarize recent advances in understanding how the worm and fly brain acquire sexually dimorphic features during development. We highlight the advantages of each system, illustrating how the precise anatomical delineation of sexual dimorphisms in worms has enabled recent analysis into how these dimorphisms become specified during development, and how focusing on sexually dimorphic neurons in the fly has enabled an increasingly detailed understanding of sex-specific behaviors.
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Affiliation(s)
- Stephen F Goodwin
- Centre for Neural Circuits and Behaviour, University of Oxford, Oxford OX1 3SR, United Kingdom;
| | - Oliver Hobert
- Department of Biological Sciences and Howard Hughes Medical Institute, Columbia University, New York, NY 10027, USA;
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22
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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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23
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Rohner PT, Linz DM, Moczek AP. Doublesex mediates species-, sex-, environment- and trait-specific exaggeration of size and shape. Proc Biol Sci 2021; 288:20210241. [PMID: 34157867 DOI: 10.1098/rspb.2021.0241] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Context-dependent trait exaggeration is a major contributor to phenotypic diversity. However, the genetic modifiers instructing development across multiple contexts remain largely unknown. We use the arthropod tibia, a hotspot for segmental differentiation, as a paradigm to assess the developmental mechanisms underlying the context-dependent structural exaggeration of size and shape through nutritional plasticity, sexual dimorphism and segmental differentiation. Using an RNAseq approach in the sexually dimorphic and male-polyphenic dung beetle Digitonthophagus gazella, we find that only a small portion (3.7%) of all transcripts covary positively in expression level with trait size across contexts. However, RNAi-mediated knockdown of the conserved sex-determination gene doublesex suggests that it functions as a context-dependent master mediator of trait exaggeration in D. gazella as well as the closely related dung beetle Onthophagus taurus. Taken together, our findings suggest (i) that the gene networks associated with trait exaggeration are highly dependent on the precise developmental context, (ii) that doublesex differentially shapes morphological exaggeration depending on developmental contexts and (iii) that this context-specificity of dsx-mediated trait exaggeration may diversify rapidly. This mechanism may contribute to the resolution of conflict arising from environment-dependent antagonistic selection among sexes and divergent developmental contexts in a wide range of animals.
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Affiliation(s)
- Patrick T Rohner
- Department of Biology, Indiana University, 915 East Third Street, 102 Myers Hall, Bloomington, IN 47405, USA
| | - David M Linz
- Department of Biology, Indiana University, 915 East Third Street, 102 Myers Hall, Bloomington, IN 47405, USA
| | - Armin P Moczek
- Department of Biology, Indiana University, 915 East Third Street, 102 Myers Hall, Bloomington, IN 47405, USA
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24
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Rohner PT. A role for sex-determination genes in life history evolution? Doublesex mediates sexual size dimorphism in the gazelle dung beetle. J Evol Biol 2021; 34:1326-1332. [PMID: 34075658 DOI: 10.1111/jeb.13877] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 04/06/2021] [Accepted: 05/09/2021] [Indexed: 02/06/2023]
Abstract
An organism's fitness depends strongly on its age and size at maturation. Although the evolutionary forces acting on these critical life history traits have been heavily scrutinized, the developmental mechanisms underpinning intraspecific variation in adult size and development time remain much less well-understood. Using RNA interference, I here show that the highly conserved sex-determination gene doublesex (dsx) mediates sexual size dimorphism (SSD) in the gazelle dung beetle Digitonthophagus gazella. Because doublesex undergoes sex-specific splicing and sex-limited isoforms regulate different target genes, this suggests that dsx contributes to the resolution of intralocus sexual conflict in body size. However, these results contrast with previous studies demonstrating that dsx does not affect body size or SSD in Drosophila. This indicates that intraspecific body size variation is underlain by contrasting developmental mechanisms in different insect lineages. Furthermore, although male D. gazella have a longer development time than females, sexual bimaturism was not affected by dsx expression knockdown. In addition, and in contrast to secondary sexual morphology, dsx did not significantly affect nutritional plasticity in life history. Taken together, these findings indicate that dsx signalling contributes to intraspecific life history variation but that dsx's function in mediating sexual dimorphism in life history differs among traits and species. More generally, these findings suggest that genes ancestrally tasked with sex determination have been co-opted into the developmental regulation of life history traits and may represent an underappreciated mechanism of life history evolution.
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25
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Toubiana W, Armisén D, Viala S, Decaras A, Khila A. The growth factor BMP11 is required for the development and evolution of a male exaggerated weapon and its associated fighting behavior in a water strider. PLoS Biol 2021; 19:e3001157. [PMID: 33974625 PMCID: PMC8112723 DOI: 10.1371/journal.pbio.3001157] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 02/25/2021] [Indexed: 11/21/2022] Open
Abstract
Exaggerated sexually selected traits, often carried by males, are characterized by the evolution of hyperallometry, resulting in their disproportionate growth relative to the rest of the body among individuals of the same population. While the evolution of allometry has attracted much attention for centuries, our understanding of the developmental genetic mechanisms underlying its emergence remains fragmented. Here we conduct comparative transcriptomics of the legs followed by an RNA interference (RNAi) screen to identify genes that play a role in the hyperallometric growth of the third legs in the males of the water strider Microvelia longipes. We demonstrate that a broadly expressed growth factor, Bone Morphogenetic Protein 11 (BMP11, also known as Growth Differentiation Factor 11), regulates leg allometries through increasing the allometric slope and mean body size in males. In contrast, BMP11 RNAi reduced mean body size but did not affect slope either in the females of M. longipes or in the males and females of other closely related Microvelia species. Furthermore, our data show that a tissue-specific factor, Ultrabithorax (Ubx), increases intercept without affecting mean body size. This indicates a genetic correlation between mean body size and variation in allometric slope, but not intercept. Strikingly, males treated with BMP11 RNAi exhibited a severe reduction in fighting frequency compared to both controls and Ubx RNAi-treated males. Therefore, male body size, the exaggerated weapon, and the intense fighting behavior associated with it are genetically correlated in M. longipes. Our results support a possible role of pleiotropy in the evolution of allometric slope.
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Affiliation(s)
- William Toubiana
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Claude Bernard Lyon 1, Centre National de la Recherche Scientifique Unité Mixte de Recherche 5242, Ecole Normale Supérieure de Lyon, Lyon, France
| | - David Armisén
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Claude Bernard Lyon 1, Centre National de la Recherche Scientifique Unité Mixte de Recherche 5242, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Séverine Viala
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Claude Bernard Lyon 1, Centre National de la Recherche Scientifique Unité Mixte de Recherche 5242, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Amélie Decaras
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Claude Bernard Lyon 1, Centre National de la Recherche Scientifique Unité Mixte de Recherche 5242, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Abderrahman Khila
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Claude Bernard Lyon 1, Centre National de la Recherche Scientifique Unité Mixte de Recherche 5242, Ecole Normale Supérieure de Lyon, Lyon, France
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26
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Toubiana W, Armisén D, Dechaud C, Arbore R, Khila A. Impact of male trait exaggeration on sex-biased gene expression and genome architecture in a water strider. BMC Biol 2021; 19:89. [PMID: 33931057 PMCID: PMC8088084 DOI: 10.1186/s12915-021-01021-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 04/01/2021] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Exaggerated secondary sexual traits are widespread in nature and often evolve under strong directional sexual selection. Although heavily studied from both theoretical and empirical viewpoints, we have little understanding of how sexual selection influences sex-biased gene regulation during the development of exaggerated secondary sexual phenotypes, and how these changes are reflected in genomic architecture. This is primarily due to the limited availability of representative genomes and associated tissue and sex transcriptomes to study the development of these traits. Here we present the genome and developmental transcriptomes, focused on the legs, of the water strider Microvelia longipes, a species where males exhibit strikingly long third legs compared to females, which they use as weapons. RESULTS We generated a high-quality genome assembly with 90% of the sequence captured in 13 scaffolds. The most exaggerated legs in males were particularly enriched in both sex-biased and leg-biased genes, indicating a specific signature of gene expression in association with trait exaggeration. We also found that male-biased genes showed patterns of fast evolution compared to non-biased and female-biased genes, indicative of directional or relaxed purifying selection. By contrast to male-biased genes, female-biased genes that are expressed in the third legs, but not the other legs, are over-represented in the X chromosome compared to the autosomes. An enrichment analysis for sex-biased genes along the chromosomes revealed also that they arrange in large genomic regions or in small clusters of two to four consecutive genes. The number and expression of these enriched regions were often associated with the exaggerated legs of males, suggesting a pattern of common regulation through genomic proximity in association with trait exaggeration. CONCLUSION Our findings indicate how directional sexual selection may drive sex-biased gene expression and genome architecture along the path to trait exaggeration and sexual dimorphism.
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Affiliation(s)
- William Toubiana
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Claude Bernard Lyon1, CNRS UMR 5242, Ecole Normale Supérieure de Lyon, 46, allée d'Italie, 69364, Lyon Cedex 07, France
- Present address: Department of Ecology and Evolution, University of Lausanne, CH-1015, Lausanne, Switzerland
| | - David Armisén
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Claude Bernard Lyon1, CNRS UMR 5242, Ecole Normale Supérieure de Lyon, 46, allée d'Italie, 69364, Lyon Cedex 07, France
| | - Corentin Dechaud
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Claude Bernard Lyon1, CNRS UMR 5242, Ecole Normale Supérieure de Lyon, 46, allée d'Italie, 69364, Lyon Cedex 07, France
| | - Roberto Arbore
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Claude Bernard Lyon1, CNRS UMR 5242, Ecole Normale Supérieure de Lyon, 46, allée d'Italie, 69364, Lyon Cedex 07, France
- Present address: Instituto Gulbenkian de Ciência, Rua da Quinta Grande 6, 2780-156, Oeiras, Portugal
| | - Abderrahman Khila
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Claude Bernard Lyon1, CNRS UMR 5242, Ecole Normale Supérieure de Lyon, 46, allée d'Italie, 69364, Lyon Cedex 07, France.
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27
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Evolution of sexual development and sexual dimorphism in insects. Curr Opin Genet Dev 2021; 69:129-139. [PMID: 33848958 DOI: 10.1016/j.gde.2021.02.011] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 02/19/2021] [Accepted: 02/24/2021] [Indexed: 12/18/2022]
Abstract
Most animal species consist of two distinct sexes. At the morphological, physiological, and behavioral levels the differences between males and females are numerous and dramatic, yet at the genomic level they are often slight or absent. This disconnect is overcome because simple genetic differences or environmental signals are able to direct the sex-specific expression of a shared genome. A canonical picture of how this process works in insects emerged from decades of work on Drosophila. But recent years have seen an explosion of molecular-genetic and developmental work on a broad range of insects. Drawing these studies together, we describe the evolution of sexual dimorphism from a comparative perspective and argue that insect sex determination and differentiation systems are composites of rapidly evolving and highly conserved elements.
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Hernández ML, Acosta LE. Caracterización del dimorfismo sexual y reconocimiento de machos dimórficos en el complejo Discocyrtus prospicuus (Arachnida: Opiliones: Gonyleptidae): una aproximación desde la morfometría geométrica. REV MEX BIODIVERS 2021. [DOI: 10.22201/ib.20078706e.2021.92.3545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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29
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Jin B, Zhao Y, Liu P, Sun Y, Li X, Zhang X, Chen XG, Gu J. The direct regulation of Aalbdsx on AalVgR is indispensable for ovarian development in Aedes albopictus. PEST MANAGEMENT SCIENCE 2021; 77:1654-1667. [PMID: 33205515 DOI: 10.1002/ps.6185] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 11/13/2020] [Accepted: 11/17/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Aedes albopictus is an important vector with an extensive worldwide distribution. Only female mosquitoes play a significant role in the transmission of pathogens. Doublesex (dsx) is a central nexus gene in the insect somatic sex determination hierarchy. RESULTS In this study, we characterized the full-length sex-specific splicing forms of the Ae. albopictus dsx (Aalbdsx) gene. Then, we identified 15 direct target genes of DSX in adult females using digital gene expression combined with quantitative real-time polymerase chain reaction (qPCR) by performing a chromatin immunoprecipitation (ChIP) assay with specific DSX antibodies. Knockdown of Aalbdsx suppressed ovarian development and decreased the transcript levels of the Aalbdsx target vitellogenin receptor (VgR) gene, whereas vitellogenin (Vg) expression showed an increase in the fat body. Genes in the major Vg regulatory pathway were also up-regulated. CONCLUSION Our results suggest that both Vg and VgR are direct target genes of Aalbdsx and that direct regulation of Aalbdsx on VgR is indispensable for ovarian development in Ae. albopictus, which not only provides a reference for the further elucidation of the evolutionarily conserved role of dsx in Ae. albopictus sexual differentiation but also reveals potential molecular targets for application to the development of sterile male mosquitoes to be released for vector control. © 2020 Society of Chemical Industry.
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Affiliation(s)
- Binbin Jin
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Yijie Zhao
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Peiwen Liu
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Yan Sun
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Xiaocong Li
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Xin Zhang
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Xiao-Guang Chen
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Jinbao Gu
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
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30
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Prakash A, Monteiro A. Doublesex Mediates the Development of Sex-Specific Pheromone Organs in Bicyclus Butterflies via Multiple Mechanisms. Mol Biol Evol 2021; 37:1694-1707. [PMID: 32077943 PMCID: PMC7253200 DOI: 10.1093/molbev/msaa039] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The Bicyclus lineage of satyrid butterflies exhibits male-specific traits, the scent organs, used for chemical communication during courtship. These organs consist of tightly packed brush-like scales (hair-pencils) that rub against scent patches to disperse pheromones, but the evolution and molecular basis of these organ’s male-limited development remains unknown. Here, we examine the evolution of the number and location of the scent patches and hair-pencils within 53 species of Bicyclus butterflies, and the involvement of the sex determinant gene doublesex (dsx) in scent organ development in Bicyclus anynana using CRISPR/Cas9. We show that scent patches and hair-pencils arose via multiple, independent gains, in a correlated manner. Further, an initially nonsex-specific Dsx protein expression pattern in developing wing discs becomes male-specific and spatially refined to areas that develop the scent patches. Functional perturbations of dsx show that this gene activates patch development in males whereas hair-pencils develop in both sexes without Dsx input. Dsx in females is, instead, required to repress hair-pencils whereas Dsx in males regulates minor aspects of its development. These findings suggest that the patches and hair-pencils evolve as correlated composite organs presumably due to their functional integration. Divergence in the function of dsx isoforms occurred across the sexes, where the male isoform promotes patch development in males and the female isoform represses hair-pencil development in females, both leading to the development of male-limited traits. Furthermore, evolution in number of patches in males is due to the evolution of spatial regulation of dsx.
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Affiliation(s)
- Anupama Prakash
- Department of Biological Sciences, National University of Singapore, Singapore
| | - Antónia Monteiro
- Department of Biological Sciences, National University of Singapore, Singapore.,Yale-NUS College, Singapore
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31
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Hanna L, Abouheif E. The origin of wing polyphenism in ants: An eco-evo-devo perspective. Curr Top Dev Biol 2021; 141:279-336. [PMID: 33602491 DOI: 10.1016/bs.ctdb.2020.12.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The evolution of eusociality, where solitary individuals integrate into a single colony, is a major transition in individuality. In ants, the origin of eusociality coincided with the origin of a wing polyphenism approximately 160 million years ago, giving rise to colonies with winged queens and wingless workers. As a consequence, both eusociality and wing polyphenism are nearly universal features of all ants. Here, we synthesize fossil, ecological, developmental, and evolutionary data in an attempt to understand the factors that contributed to the origin of wing polyphenism in ants. We propose multiple models and hypotheses to explain how wing polyphenism is orchestrated at multiple levels, from environmental cues to gene networks. Furthermore, we argue that the origin of wing polyphenism enabled the subsequent evolution of morphological diversity across the ants. We finally conclude by outlining several outstanding questions for future work.
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Affiliation(s)
- Lisa Hanna
- Department of Biology, McGill University, Montreal, QC, Canada
| | - Ehab Abouheif
- Department of Biology, McGill University, Montreal, QC, Canada.
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32
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Wan X, Jiang Y, Cao Y, Sun B, Xiang X. Divergence in Gut Bacterial Community Structure between Male and Female Stag Beetles Odontolabis fallaciosa (Coleoptera, Lucanidae). Animals (Basel) 2020; 10:ani10122352. [PMID: 33317133 PMCID: PMC7764088 DOI: 10.3390/ani10122352] [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: 07/21/2020] [Revised: 11/21/2020] [Accepted: 12/07/2020] [Indexed: 12/18/2022] Open
Abstract
Simple Summary Intestinal microbiota play crucial roles for their hosts. Odontolabis fallaciosa shows striking sexual dimorphism and male trimorphism, which represents an interesting system to study their gut microbiota. We have compared the intestinal bacterial community structure between the two sexes and among three male morphs of O. fallaciosa. The gut bacterial community structure was significantly different between males and females. The females were associated with higher bacterial alpha-diversity relative to males. Large males had a higher relative abundance of Firmicutes and Firmicutes/Bacteroides (F/B) ratio, which contributed to nutritional efficiency. The results increased our understanding of beetle–bacterial interactions of O. fallaciosa between the two sexes, and among three male morphs, which might reveal the relationship among the gut microbiota, nutrition level, and phenotypic evolution of the stag beetle. Abstract Odontolabis fallaciosa (Coleoptera: Lucanidae) is a giant and popular stag beetle with striking sexual dimorphism and male trimorphism. However, little is known about their intestinal microbiota, which might play an indispensable role in shaping the health of their hosts. The aim of this study was to investigate the intestinal bacterial community structure between the two sexes and among three male morphs of O. fallaciosa from China using high-throughput sequencing (Illumina MiSeq). The gut bacterial community structure was significantly different between males and females, suggesting that sex appeared to be the crucial factor shaping the intestinal bacterial community. Females had higher bacterial alpha-diversity than males. There was little difference in gut bacterial community structure among the three male morphs. However, compared to medium and small males, large individuals were associated with the higher relative abundance of Firmicutes and Firmicutes/Bacteroides (F/B) ratio, which might contribute to nutritional efficiency. Overall, these results might help to further our understanding of beetle–bacterial interactions of O. fallaciosa between the two sexes, and among the three male morphs.
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33
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Zhu S, Liu F, Zeng H, Li N, Ren C, Su Y, Zhou S, Wang G, Palli SR, Wang J, Qin Y, Li S. Insulin/IGF signaling and TORC1 promote vitellogenesis via inducing juvenile hormone biosynthesis in the American cockroach. Development 2020; 147:147/20/dev188805. [PMID: 33097549 DOI: 10.1242/dev.188805] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 09/18/2020] [Indexed: 11/20/2022]
Abstract
Vitellogenesis, including vitellogenin (Vg) production in the fat body and Vg uptake by maturing oocytes, is of great importance for the successful reproduction of adult females. The endocrinal and nutritional regulation of vitellogenesis differs distinctly in insects. Here, the complex crosstalk between juvenile hormone (JH) and the two nutrient sensors insulin/IGF signaling (IIS) and target of rapamycin complex1 (TORC1), was investigated to elucidate the molecular mechanisms of vitellogenesis regulation in the American cockroach, Periplaneta americana Our data showed that a block of JH biosynthesis or JH action arrested vitellogenesis, in part by inhibiting the expression of doublesex (Dsx), a key transcription factor gene involved in the sex determination cascade. Depletion of IIS or TORC1 blocked both JH biosynthesis and vitellogenesis. Importantly, the JH analog methoprene, but not bovine insulin (to restore IIS) and amino acids (to restore TORC1 activity), restored vitellogenesis in the neck-ligated (IIS-, TORC1- and JH-deficient) and rapamycin-treated (TORC1- and JH-deficient) cockroaches. Combining classic physiology with modern molecular techniques, we have demonstrated that IIS and TORC1 promote vitellogenesis, mainly via inducing JH biosynthesis in the American cockroach.
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Affiliation(s)
- Shiming Zhu
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology and School of Life Sciences, South China Normal University, Guangzhou 510631, China.,Guangmeiyuan R&D Center, Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, South China Normal University, Meizhou 514779, China
| | - Fangfang Liu
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology and School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Huanchao Zeng
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology and School of Life Sciences, South China Normal University, Guangzhou 510631, China.,Guangmeiyuan R&D Center, Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, South China Normal University, Meizhou 514779, China
| | - Na Li
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology and School of Life Sciences, South China Normal University, Guangzhou 510631, China.,Guangmeiyuan R&D Center, Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, South China Normal University, Meizhou 514779, China
| | - Chonghua Ren
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology and School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Yunlin Su
- Molecular Analysis and Genetic Improvement Center South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
| | - Shutang Zhou
- Key Laboratory of Plant Stress Biology, State Key Laboratory of Cotton Biology, School of Life Sciences, Henan University, Kaifeng 475001, China
| | - Guirong Wang
- Lingnan Guangdong Laboratory of Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China
| | - Subba Reddy Palli
- Department of Entomology, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY 40546, USA
| | - Jian Wang
- Department of Entomology, University of Maryland, College Park, MD 20742, USA
| | - Yiru Qin
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology and School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Sheng Li
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology and School of Life Sciences, South China Normal University, Guangzhou 510631, China .,Guangmeiyuan R&D Center, Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, South China Normal University, Meizhou 514779, China
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34
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Walton A, Sheehan MJ, Toth AL. Going wild for functional genomics: RNA interference as a tool to study gene-behavior associations in diverse species and ecological contexts. Horm Behav 2020; 124:104774. [PMID: 32422196 DOI: 10.1016/j.yhbeh.2020.104774] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Revised: 05/08/2020] [Accepted: 05/11/2020] [Indexed: 12/25/2022]
Abstract
Identifying the genetic basis of behavior has remained a challenge for biologists. A major obstacle to this goal is the difficulty of examining gene function in an ecologically relevant context. New tools such as CRISPR/Cas9, which alter the germline of an organism, have taken center stage in functional genomics in non-model organisms. However, germline modifications of this nature cannot be ethically implemented in the wild as a part of field experiments. This impediment is more than technical. Gene function is intimately tied to the environment in which the gene is expressed, especially for behavior. Most lab-based studies fail to recapitulate an organism's ecological niche, thus most published functional genomics studies of gene-behavior relationships may provide an incomplete or even inaccurate assessment of gene function. In this review, we highlight RNA interference as an especially effective experimental method to deepen our understanding of the interplay between genes, behavior, and the environment. We highlight the utility of RNAi for researchers investigating behavioral genetics, noting unique attributes of RNAi including transience of effect and the feasibility of releasing treated animals into the wild, that make it especially useful for studying the function of behavior-related genes. Furthermore, we provide guidelines for planning and executing an RNAi experiment to study behavior, including challenges to consider. We urge behavioral ecologists and functional genomicists to adopt a more fully integrated approach which we call "ethological genomics". We advocate this approach, utilizing tools such as RNAi, to study gene-behavior relationships in their natural context, arguing that such studies can provide a deeper understanding of how genes can influence behavior, as well as ecological aspects beyond the organism that houses them.
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Affiliation(s)
- Alexander Walton
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA, USA.
| | - Michael J Sheehan
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY, USA
| | - Amy L Toth
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA, USA; Department of Entomology, Iowa State University, Ames, IA, USA
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35
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Apirajkamol N(B, James B, Gordon KHJ, Walsh TK, McGaughran A. Oxidative stress delays development and alters gene expression in the agricultural pest moth, Helicoverpa armigera. Ecol Evol 2020; 10:5680-5693. [PMID: 32607183 PMCID: PMC7319138 DOI: 10.1002/ece3.6308] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2020] [Revised: 03/27/2020] [Accepted: 04/03/2020] [Indexed: 12/30/2022] Open
Abstract
Stress is a widespread phenomenon that all organisms must endure. Common in nature is oxidative stress, which can interrupt cell homeostasis to cause cell damage and may be derived from respiration or from environmental exposure through diet. As a result of the routine exposure from respiration, many organisms can mitigate the effects of oxidative stress, but less is known about responses to oxidative stress from other sources. Helicoverpa armigera is a major agricultural pest moth that causes significant damage to crops worldwide. Here, we examined the effects of oxidative stress on H. armigera by chronically exposing individuals to paraquat-a free radical producer-and measuring changes in development (weight, developmental rate, lifespan), and gene expression. We found that oxidative stress strongly affected development in H. armigera, with stressed samples spending more time as caterpillars than control samples (>24 vs. ~15 days, respectively) and therefore living longer overall. We found 1,618 up- and 761 down-regulated genes, respectively, in stressed versus control samples. In the up-regulated gene set, was an over-representation of biological processes related to cuticle and chitin development, glycine metabolism, and oxidation-reduction. Oxidative stress clearly impacts physiology and biochemistry in H. armigera and the interesting finding of an extended lifespan in stressed individuals could demonstrate hormesis, the phenomenon whereby toxic compounds can actually be beneficial at low doses. Collectively, our findings provide new insights into physiological and gene expression responses to oxidative stress in invertebrates.
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Affiliation(s)
- Nonthakorn (Beatrice) Apirajkamol
- Division of Ecology and EvolutionAustralian National UniversityCanberraACTAustralia
- Black Mountain LaboratoriesCommonwealth Scientific and Industrial Research OrganisationCanberraACTAustralia
| | - Bill James
- Black Mountain LaboratoriesCommonwealth Scientific and Industrial Research OrganisationCanberraACTAustralia
| | - Karl H. J. Gordon
- Black Mountain LaboratoriesCommonwealth Scientific and Industrial Research OrganisationCanberraACTAustralia
| | - Tom K. Walsh
- Black Mountain LaboratoriesCommonwealth Scientific and Industrial Research OrganisationCanberraACTAustralia
- Adjunct FellowMacquarie UniversitySydneyNSWAustralia
| | - Angela McGaughran
- Division of Ecology and EvolutionAustralian National UniversityCanberraACTAustralia
- Black Mountain LaboratoriesCommonwealth Scientific and Industrial Research OrganisationCanberraACTAustralia
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36
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Casasa S, Zattara EE, Moczek AP. Nutrition-responsive gene expression and the developmental evolution of insect polyphenism. Nat Ecol Evol 2020; 4:970-978. [PMID: 32424280 DOI: 10.1038/s41559-020-1202-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 04/09/2020] [Indexed: 01/05/2023]
Abstract
Nutrition-responsive development is a ubiquitous and highly diversified example of phenotypic plasticity, yet its underlying molecular and developmental mechanisms and modes of evolutionary diversification remain poorly understood. We measured genome-wide transcription in three closely related species of horned beetles exhibiting strikingly diverse degrees of nutrition responsiveness in the development of male weaponry. We show that (1) counts of differentially expressed genes between low- and high-nutritional backgrounds mirror species-specific degrees of morphological nutrition responsiveness; (2) evolutionary exaggeration of morphological responsiveness is underlain by both amplification of ancestral nutrition-responsive gene expression and recruitment of formerly low nutritionally responsive genes; and (3) secondary loss of morphological responsiveness to nutrition coincides with a dramatic reduction in gene expression plasticity. Our results further implicate genetic accommodation of ancestrally high variability of gene expression plasticity in both exaggeration and loss of nutritional plasticity, yet reject a major role of taxon-restricted genes in the developmental regulation and evolution of nutritional plasticity.
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Affiliation(s)
- Sofia Casasa
- Department of Biology, Indiana University, Bloomington, IN, USA.
| | - Eduardo E Zattara
- Department of Biology, Indiana University, Bloomington, IN, USA. .,INIBIOMA, Universidad Nacional del Comahue - CONICET, Bariloche, Argentina.
| | - Armin P Moczek
- Department of Biology, Indiana University, Bloomington, IN, USA
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37
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Muramatsu M, Tsuji T, Tanaka S, Shiotsuki T, Jouraku A, Miura K, Vea IM, Minakuchi C. Sex-specific expression profiles of ecdysteroid biosynthesis and ecdysone response genes in extreme sexual dimorphism of the mealybug Planococcus kraunhiae (Kuwana). PLoS One 2020; 15:e0231451. [PMID: 32282855 PMCID: PMC7153872 DOI: 10.1371/journal.pone.0231451] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 03/24/2020] [Indexed: 01/22/2023] Open
Abstract
Insect molting hormone (ecdysteroids) and juvenile hormone regulate molting and metamorphic events in a variety of insect species. Mealybugs undergo sexually dimorphic metamorphosis: males develop into winged adults through non-feeding, pupa-like stages called prepupa and pupa, while females emerge as neotenic wingless adults. We previously demonstrated, in the Japanese mealybug Planococcus kraunhiae (Kuwana), that the juvenile hormone titer is higher in males than in females at the end of the juvenile stage, which suggests that juvenile hormone may regulate male-specific adult morphogenesis. Here, we examined the involvement of ecdysteroids in sexually dimorphic metamorphosis. To estimate ecdysteroid titers, quantitative RT-PCR analyses of four Halloween genes encoding for cytochrome P450 monooxygenases in ecdysteroid biosynthesis, i.e., spook, disembodied, shadow and shade, were performed. Overall, their expression levels peaked before each nymphal molt. Transcript levels of spook, disembodied and shadow, genes that catalyze the steps in ecdysteroid biosynthesis in the prothoracic gland, were higher in males from the middle of the second nymphal instar to adult emergence. In contrast, the expression of shade, which was reported to be involved in the conversion of ecdysone into 20-hydroxyecdysone in peripheral tissues, was similar between males and females. These results suggest that ecdysteroid biosynthesis in the prothoracic gland is more active in males than in females, although the final conversion into 20-hydroxyecdysone occurs at similar levels in both sexes. Moreover, expression profiles of ecdysone response genes, ecdysone receptor and ecdysone-induced protein 75B, were also analyzed. Based on these expression profiles, we propose that the changes in ecdysteroid titer differ between males and females, and that high ecdysteroid titer is essential for directing male adult development.
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Affiliation(s)
- Miyuki Muramatsu
- Graduate School of Bio-Agricultural Sciences, Nagoya University, Nagoya, Japan
| | - Tomohiro Tsuji
- Graduate School of Bio-Agricultural Sciences, Nagoya University, Nagoya, Japan
| | - Sayumi Tanaka
- Graduate School of Bio-Agricultural Sciences, Nagoya University, Nagoya, Japan
| | - Takahiro Shiotsuki
- Faculty of Life and Environmental Science, Shimane University, Matsue, Japan
| | - Akiya Jouraku
- Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Tsukuba, Japan
| | - Ken Miura
- Graduate School of Bio-Agricultural Sciences, Nagoya University, Nagoya, Japan
| | - Isabelle Mifom Vea
- Graduate School of Bio-Agricultural Sciences, Nagoya University, Nagoya, Japan
| | - Chieka Minakuchi
- Graduate School of Bio-Agricultural Sciences, Nagoya University, Nagoya, Japan
- * E-mail:
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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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Bhardwaj S, Jolander LSH, Wenk MR, Oliver JC, Nijhout HF, Monteiro A. Origin of the mechanism of phenotypic plasticity in satyrid butterfly eyespots. eLife 2020; 9:49544. [PMID: 32041684 PMCID: PMC7012602 DOI: 10.7554/elife.49544] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 01/08/2020] [Indexed: 12/14/2022] Open
Abstract
Plasticity is often regarded as a derived adaptation to help organisms survive in variable but predictable environments, however, we currently lack a rigorous, mechanistic examination of how plasticity evolves in a large comparative framework. Here, we show that phenotypic plasticity in eyespot size in response to environmental temperature observed in Bicyclus anynana satyrid butterflies is a complex derived adaptation of this lineage. By reconstructing the evolution of known physiological and molecular components of eyespot size plasticity in a comparative framework, we showed that 20E titer plasticity in response to temperature is a pre-adaptation shared by all butterfly species examined, whereas expression of EcR in eyespot centers, and eyespot sensitivity to 20E, are both derived traits found only in a subset of species with eyespots. A well-known family of butterflies have circular patterns on their wings that look like eyes. These eye-like markings help deflect predators away from the butterfly’s body so they attack the outer edges of their wings. However, in certain seasons, such as the dry season in Africa, the best way for this family to survive is by not drawing any attention to their bodies. Thus, butterflies born during this season shrink the size of their eyespots so they can hide among the dry leaves. How this family of butterflies are able to change the size of these eye-like spots has only been studied in the species Bicyclus anynana. During development low temperatures, which signify the beginning of the dry season, reduce the amount of a hormone called 20E circulating in the blood of this species. This changes the behavior of hormone-sensitive cells in the eyespots making them smaller in size. But it remains unclear how B. anynana evolved this remarkable tactic and whether its relatives have similar abilities. Now, Bhardwaj et al. show that B. anynana is the only one of its relatives that can amend the size of its eyespots in response to temperature changes. In the experiments, 13 different species of butterflies, mostly from the family that has eyespots, were developed under two different temperatures. Low temperatures caused 20E hormone levels to decrease in all 13 species. However, most of these species did not develop smaller eyespots in response to this temperature change. This includes species that are known to have larger and smaller eyespots depending on the season. Like B. anynana, four of the species studied have receptors for the 20E hormone at the center of their eyespots. However, changing 20E hormone levels in these species did not reduce eyespot size. These results show that although temperature changes alter hormone levels in a number of species, only B. anynana have taken advantage of this mechanism to regulate eyespot size. In addition, Bhardwaj et al. found that this unique mechanism evolved from several genetic changes over millions of years. Other species likely use other environmental cues to trigger seasonal changes in the size of their eyespots.
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Affiliation(s)
- Shivam Bhardwaj
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Lim Si-Hui Jolander
- Department of Biochemistry, National University of Singapore, Singapore, Singapore
| | - Markus R Wenk
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore.,Department of Biochemistry, National University of Singapore, Singapore, Singapore
| | - Jeffrey C Oliver
- Office of Digital Innovation & Stewardship, University of Arizona, Tucson, United States
| | | | - Antonia Monteiro
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore.,Yale-NUS College, Singapore, Singapore
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Ng'oma E, Williams-Simon PA, Rahman A, King EG. Diverse biological processes coordinate the transcriptional response to nutritional changes in a Drosophila melanogaster multiparent population. BMC Genomics 2020; 21:84. [PMID: 31992183 PMCID: PMC6988245 DOI: 10.1186/s12864-020-6467-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 01/08/2020] [Indexed: 12/19/2022] Open
Abstract
Background Environmental variation in the amount of resources available to populations challenge individuals to optimize the allocation of those resources to key fitness functions. This coordination of resource allocation relative to resource availability is commonly attributed to key nutrient sensing gene pathways in laboratory model organisms, chiefly the insulin/TOR signaling pathway. However, the genetic basis of diet-induced variation in gene expression is less clear. Results To describe the natural genetic variation underlying nutrient-dependent differences, we used an outbred panel derived from a multiparental population, the Drosophila Synthetic Population Resource. We analyzed RNA sequence data from multiple female tissue samples dissected from flies reared in three nutritional conditions: high sugar (HS), dietary restriction (DR), and control (C) diets. A large proportion of genes in the experiment (19.6% or 2471 genes) were significantly differentially expressed for the effect of diet, and 7.8% (978 genes) for the effect of the interaction between diet and tissue type (LRT, Padj. < 0.05). Interestingly, we observed similar patterns of gene expression relative to the C diet, in the DR and HS treated flies, a response likely reflecting diet component ratios. Hierarchical clustering identified 21 robust gene modules showing intra-modularly similar patterns of expression across diets, all of which were highly significant for diet or diet-tissue interaction effects (FDR Padj. < 0.05). Gene set enrichment analysis for different diet-tissue combinations revealed a diverse set of pathways and gene ontology (GO) terms (two-sample t-test, FDR < 0.05). GO analysis on individual co-expressed modules likewise showed a large number of terms encompassing many cellular and nuclear processes (Fisher exact test, Padj. < 0.01). Although a handful of genes in the IIS/TOR pathway including Ilp5, Rheb, and Sirt2 showed significant elevation in expression, many key genes such as InR, chico, most insulin peptide genes, and the nutrient-sensing pathways were not observed. Conclusions Our results suggest that a more diverse network of pathways and gene networks mediate the diet response in our population. These results have important implications for future studies focusing on diet responses in natural populations.
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Affiliation(s)
- E Ng'oma
- University of Missouri, 401 Tucker Hall, Columbia, MO, 65211, USA.
| | | | - A Rahman
- University of Missouri, 401 Tucker Hall, Columbia, MO, 65211, USA
| | - E G King
- University of Missouri, 401 Tucker Hall, Columbia, MO, 65211, USA
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García-Reina A, Rossi E, Galián J. Effects of lipopolysaccharide and juvenile hormone III treatments on cell growth and gene expression in the Ceratitis capitata (Diptera: Tephritidae) CCE/CC128 cell line. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2019; 102:e21617. [PMID: 31512283 DOI: 10.1002/arch.21617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 06/27/2019] [Accepted: 08/16/2019] [Indexed: 06/10/2023]
Abstract
The Mediterranean fruit fly Ceratitis capitata is one of the most important insect pest species in the world. It has a high colonization capacity and population variety, giving it considerable genetic diversity. Strategies for its control have included the sterile insect technique and insect growth regulators. Many studies have analyzed the medfly transcriptome, and along with the medfly genome sequence, the sequences of multiple genes related to sex determination, mating, development, pheromone detection, immunity, or stress have been identified. In this study, the medfly CCE/CC128 cell line was used to assess cell growth variation and changes in the expression of genes covering different functions, after lipopolysaccharide (LPS) and juvenile hormone III (JHIII) treatments. No significant effects on cell growth and gene expression were observed in the cells treated with LPS. In the cells treated with JHIII, the results showed significant effects on cell growth, and an overexpression was found of the Shade gene, one of the Halloween gene members of the cytochrome p450 family, which is involved in development and the synthesis of 20-hydroxyecdysone. This study shows preliminary results on the insect cell line in combination with whole-genome sequencing, which can facilitate studies regarding growth, toxicity, immunity, and transcriptome regulations as a response to different compounds and environmental alterations.
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Affiliation(s)
- Andrés García-Reina
- Department of Zoology and Physical Anthropology, Faculty of Veterinary, Campus Mare Nostrum, University of Murcia, Murcia, Spain
| | | | - José Galián
- Department of Zoology and Physical Anthropology, Faculty of Veterinary, Campus Mare Nostrum, University of Murcia, Murcia, Spain
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Casasa S, Moczek AP. Evolution of, and via, Developmental Plasticity: Insights through the Study of Scaling Relationships. Integr Comp Biol 2019; 59:1346-1355. [PMID: 31147701 DOI: 10.1093/icb/icz086] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Scaling relationships emerge from differential growth of body parts relative to each other. As such, scaling relationships are at least in part the product of developmental plasticity. While some of the developmental genetic mechanisms underlying scaling relationships are starting to be elucidated, how these mechanisms evolve and give rise to the enormous diversity of allometric scaling observed in nature is less understood. Furthermore, developmental plasticity has itself been proposed as a mechanism that facilitates adaptation and diversification, yet its role in the developmental evolution of scaling relationships remains largely unknown. In this review, we first explore how the mechanisms of scaling relationships have evolved. We primarily focus on insect development and review how pathway components and pathway interactions have evolved across taxa to regulate scaling relationships across diverse traits. We then discuss the potential role of developmental plasticity in the evolution of scaling relationships. Specifically, we address the potential role of allometric plasticity and cryptic genetic variation in allometry in facilitating divergence via genetic accommodation. Collectively, in this article, we aim to bring together two aspects of developmental plasticity: the mechanistic underpinnings of scaling relationships and their evolution, and the potential role that plasticity plays in the evolutionary diversification of scaling relationships.
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Affiliation(s)
- Sofia Casasa
- Department of Biology, Indiana University, Bloomington, IN 47405, USA
| | - Armin P Moczek
- Department of Biology, Indiana University, Bloomington, IN 47405, USA
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Hu Y, Linz DM, Parker ES, Schwab DB, Casasa S, Macagno ALM, Moczek AP. Developmental bias in horned dung beetles and its contributions to innovation, adaptation, and resilience. Evol Dev 2019; 22:165-180. [PMID: 31475451 DOI: 10.1111/ede.12310] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Developmental processes transduce diverse influences during phenotype formation, thereby biasing and structuring amount and type of phenotypic variation available for evolutionary processes to act on. The causes, extent, and consequences of this bias are subject to significant debate. Here we explore the role of developmental bias in contributing to organisms' ability to innovate, to adapt to novel or stressful conditions, and to generate well integrated, resilient phenotypes in the face of perturbations. We focus our inquiry on one taxon, the horned dung beetle genus Onthophagus, and review the role developmental bias might play across several levels of biological organization: (a) gene regulatory networks that pattern specific body regions; (b) plastic developmental mechanisms that coordinate body wide responses to changing environments and; (c) developmental symbioses and niche construction that enable organisms to build teams and to actively modify their own selective environments. We posit that across all these levels developmental bias shapes the way living systems innovate, adapt, and withstand stress, in ways that can alternately limit, bias, or facilitate developmental evolution. We conclude that the structuring contribution of developmental bias in evolution deserves further study to better understand why and how developmental evolution unfolds the way it does.
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Affiliation(s)
- Yonggang Hu
- Department of Biology, Indiana University, Bloomington, Indiana
| | - David M Linz
- Department of Biology, Indiana University, Bloomington, Indiana
| | - Erik S Parker
- Department of Biology, Indiana University, Bloomington, Indiana
| | - Daniel B Schwab
- Department of Biology, Indiana University, Bloomington, Indiana
| | - Sofia Casasa
- Department of Biology, Indiana University, Bloomington, Indiana
| | | | - Armin P Moczek
- Department of Biology, Indiana University, Bloomington, Indiana
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Panara V, Budd GE, Janssen R. Phylogenetic analysis and embryonic expression of panarthropod Dmrt genes. Front Zool 2019; 16:23. [PMID: 31303887 PMCID: PMC6604209 DOI: 10.1186/s12983-019-0322-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 06/03/2019] [Indexed: 02/08/2023] Open
Abstract
Background One set of the developmentally important Doublesex and Male-abnormal-3 Related Transcription factors (Dmrt) is subject of intense research, because of their role in sex-determination and sexual differentiation. This likely non-monophyletic group of Dmrt genes is represented by the Drosophila melanogaster gene Doublesex (Dsx), the Caenorhabditis elegans Male-abnormal-3 (Mab-3) gene, and vertebrate Dmrt1 genes. However, other members of the Dmrt family are much less well studied, and in arthropods, including the model organism Drosophila melanogaster, data on these genes are virtually absent with respect to their embryonic expression and function. Results Here we investigate the complete set of Dmrt genes in members of all main groups of Arthropoda and a member of Onychophora, extending our data to Panarthropoda as a whole. We confirm the presence of at least four families of Dmrt genes (including Dsx-like genes) in Panarthropoda and study their expression profiles during embryogenesis. Our work shows that the expression patterns of Dmrt11E, Dmrt93B, and Dmrt99B orthologs are highly conserved among panarthropods. Embryonic expression of Dsx-like genes, however, is more derived, likely as a result of neo-functionalization after duplication. Conclusions Our data suggest deep homology of most of the panarthropod Dmrt genes with respect to their function that likely dates back to their last common ancestor. The function of Dsx and Dsx-like genes which are critical for sexual differentiation in animals, however, appears to be much less conserved. Electronic supplementary material The online version of this article (10.1186/s12983-019-0322-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Virginia Panara
- 1Department of Earth Sciences, Palaeobiology, Uppsala University, Villavägen 16, Uppsala, Sweden.,Present address: Department for Immunology, Genetic and Pathology, Rudbeckslaboratoriet, Dag Hammarskjölds väg 20, Uppsala, Sweden
| | - Graham E Budd
- 1Department of Earth Sciences, Palaeobiology, Uppsala University, Villavägen 16, Uppsala, Sweden
| | - Ralf Janssen
- 1Department of Earth Sciences, Palaeobiology, Uppsala University, Villavägen 16, Uppsala, Sweden
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O'Brien DM, Boisseau RP, Duell M, McCullough E, Powell EC, Somjee U, Solie S, Hickey AJ, Holwell GI, Painting CJ, Emlen DJ. Muscle mass drives cost in sexually selected arthropod weapons. Proc Biol Sci 2019; 286:20191063. [PMID: 31238851 DOI: 10.1098/rspb.2019.1063] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Sexually selected weapons often function as honest signals of fighting ability. If poor-quality individuals produce high-quality weapons, then receivers should focus on other, more reliable signals. Cost is one way to maintain signal integrity. The costs of weapons tend to increase with relative weapon size, and thereby restrict large weapons to high-quality individuals who can produce and maintain them. Weapon cost, however, appears to be unpredictably variable both within and across taxa, and the mechanisms underlying this variation remain unclear. We suggest variation in weapon cost may result from variation in weapon composition-specifically, differences in the amount of muscle mass directly associated with the weapon. We test this idea by measuring the metabolic cost of sexually selected weapons in seven arthropod species and relating these measures to weapon muscle mass. We show that individuals with relatively large weapon muscles have disproportionately high resting metabolic rates and provide evidence that this trend is driven by weapon muscle mass. Overall, our results suggest that variation in weapon cost can be partially explained by variation in weapon morphology and that the integrity of weapon signals may be maintained by increased metabolic cost in species with relatively high weapon muscle mass.
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Affiliation(s)
- Devin M O'Brien
- 1 Department of Biological Sciences, Colby College , Waterville, ME , USA.,2 Division of Biological Sciences, University of Montana , Missoula, MT , USA
| | - Romain P Boisseau
- 2 Division of Biological Sciences, University of Montana , Missoula, MT , USA
| | - Meghan Duell
- 3 School of Life Sciences, Arizona State University , Tempe, AZ , USA
| | - Erin McCullough
- 4 Department of Biology, Syracuse University , Syracuse, NY , USA
| | - Erin C Powell
- 5 School of Biological Sciences, University of Auckland , Auckland , New Zealand
| | - Ummat Somjee
- 6 Entomology and Nematology Department, University of Florida , Gainesville, FL , USA.,7 Smithsonian Tropical Research Institute , Balboa , Ancón , Panamá
| | - Sarah Solie
- 2 Division of Biological Sciences, University of Montana , Missoula, MT , USA.,8 Biology Department, Duke University , Durham, NC , USA
| | - Anthony J Hickey
- 5 School of Biological Sciences, University of Auckland , Auckland , New Zealand
| | - Gregory I Holwell
- 5 School of Biological Sciences, University of Auckland , Auckland , New Zealand
| | - Christina J Painting
- 5 School of Biological Sciences, University of Auckland , Auckland , New Zealand
| | - Douglas J Emlen
- 2 Division of Biological Sciences, University of Montana , Missoula, MT , USA
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Baral S, Arumugam G, Deshmukh R, Kunte K. Genetic architecture and sex-specific selection govern modular, male-biased evolution of doublesex. SCIENCE ADVANCES 2019; 5:eaau3753. [PMID: 31086812 PMCID: PMC6506240 DOI: 10.1126/sciadv.aau3753] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 03/29/2019] [Indexed: 06/09/2023]
Abstract
doublesex regulates early embryonic sex differentiation in holometabolous insects, along with the development of species-, sex-, and morph-specific adaptations during pupal stages. How does a highly conserved gene with a critical developmental role also remain functionally dynamic enough to gain ecologically important adaptations that are divergent in sister species? We analyzed patterns of exon-level molecular evolution and protein structural homology of doublesex from 145 species of four insect orders representing 350 million years of divergence. This analysis revealed that evolution of doublesex was governed by a modular architecture: Functional domains and female-specific regions were highly conserved, whereas male-specific sequences and protein structures evolved up to thousand-fold faster, with sites under pervasive and/or episodic positive selection. This pattern of sex bias was reversed in Hymenoptera. Thus, highly conserved yet dynamic master regulators such as doublesex may partition specific conserved and novel functions in different genic modules at deep evolutionary time scales.
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Taracena ML, Hunt CM, Benedict MQ, Pennington PM, Dotson EM. Downregulation of female doublesex expression by oral-mediated RNA interference reduces number and fitness of Anopheles gambiae adult females. Parasit Vectors 2019; 12:170. [PMID: 30992032 PMCID: PMC6466716 DOI: 10.1186/s13071-019-3437-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 04/05/2019] [Indexed: 12/21/2022] Open
Abstract
Background Mosquito-borne diseases affect millions worldwide, with malaria alone killing over 400 thousand people per year and affecting hundreds of millions. To date, the best strategy to prevent the disease remains insecticide-based mosquito control. However, insecticide resistance as well as economic and social factors reduce the effectiveness of the current methodologies. Alternative control technologies are in development, including genetic control such as the sterile insect technique (SIT). The SIT is a pivotal tool in integrated agricultural pest management and could be used to improve malaria vector control. To apply the SIT and most other newer technologies against disease transmitting mosquitoes, it is essential that releases are composed of males with minimal female contamination. The removal of females is an essential requirement because released females can themselves contribute towards nuisance biting and disease transmission. Thus, females need to be eliminated from the cohorts prior to release. Manual separation of Anopheles gambiae pupae or adult mosquitoes based on morphology is time consuming, is not feasible on a large scale and has limited the implementation of the SIT technique. The doublesex (dsx) gene is one of the effector switches of sex determination in the process of sex differentiation in insects. Both males and females have specific splicing variants that are expressed across the different life stages. Using RNA interference (RNAi) to reduce expression of the female specific (dsxF) variant of this gene has proven to have detrimental effects to the females in other mosquito species, such as Aedes aegypti. We tested oral RNAi on dsx (AgdsxF) in An. gambiae. Methods We studied the expression pattern of the dsx gene in the An. gambiae G3 strain. We knocked down AgdsxF expression in larvae through oral delivery of double stranded RNA (dsRNA) produced by bacteria and observed its effects in adults. Results Our results show that feeding of AgdsxF dsRNA can effectively reduce (> 66%) the mRNA of female dsx transcript and that there is a concomitant reduction in the number of female larvae that achieve adulthood. Control groups produced 52% (± 3.9% SE) of adult males and 48% (± 4.0% SE) females, while AgdsxF dsRNA treated groups had 72.1% (± 4.0% SE) males vs 27.8% females (± 3.3% SE). In addition, the female adults produce fewer progeny, 37.1% (± 8.2% SE) less than the controls. The knockdown was sex-specific and had no impact on total numbers of viable male adults, in the male dsx transcripts or male fitness parameters such as longevity or body size. Conclusions These findings indicate that RNAi could be used to improve novel mosquito control strategies that require efficient sex separation and male-only release of An. gambiae by targeting sex determination genes such as AgdsxF. The advantages of using RNAi in a controlled setting for mosquito rearing are numerous, as the dose and time of exposure are controlled, and the possibility of off-target effects and the waste of female production would be significantly reduced. Electronic supplementary material The online version of this article (10.1186/s13071-019-3437-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Mabel L Taracena
- Centers for Disease Control and Prevention (CDC), 1600 Clifton Road, NE, Atlanta, GA, 30329-4027, MS G49, USA.
| | - Catherine M Hunt
- Centers for Disease Control and Prevention (CDC), 1600 Clifton Road, NE, Atlanta, GA, 30329-4027, MS G49, USA
| | - Mark Q Benedict
- Centers for Disease Control and Prevention (CDC), 1600 Clifton Road, NE, Atlanta, GA, 30329-4027, MS G49, USA
| | - Pamela M Pennington
- Centro de Estudios en Biotecnologia, Universidad del Valle de Guatemala, 18 Avenida 11-95, 01015, Guatemala City, Guatemala
| | - Ellen M Dotson
- Centers for Disease Control and Prevention (CDC), 1600 Clifton Road, NE, Atlanta, GA, 30329-4027, MS G49, USA
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Morita S, Ando T, Maeno A, Mizutani T, Mase M, Shigenobu S, Niimi T. Precise staging of beetle horn formation in Trypoxylus dichotomus reveals the pleiotropic roles of doublesex depending on the spatiotemporal developmental contexts. PLoS Genet 2019; 15:e1008063. [PMID: 30969957 PMCID: PMC6457530 DOI: 10.1371/journal.pgen.1008063] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 03/03/2019] [Indexed: 11/19/2022] Open
Abstract
Many scarab beetles have sexually dimorphic exaggerated horns that are an evolutionary novelty. Since the shape, number, size, and location of horns are highly diverged within Scarabaeidae, beetle horns are an attractive model for studying the evolution of sexually dimorphic and novel traits. In beetles including the Japanese rhinoceros beetle Trypoxylus dichotomus, the sex differentiation gene doublesex (dsx) plays a crucial role in sexually dimorphic horn formation during larval-pupal development. However, knowledge of when and how dsx drives the gene regulatory network (GRN) for horn formation to form sexually dimorphic horns during development remains elusive. To address this issue, we identified a Trypoxylus-ortholog of the sex determination gene, transformer (tra), that regulates sex-specific splicing of the dsx pre-mRNA, and whose loss of function results in sex transformation. By knocking down tra function at multiple developmental timepoints during larval-pupal development, we estimated the onset when the sex-specific GRN for horn formation is driven. In addition, we also revealed that dsx regulates different aspects of morphogenetic activities during the prepupal and pupal developmental stages to form appropriate morphologies of pupal head and thoracic horn primordia as well as those of adult horns. Based on these findings, we discuss the evolutionary developmental background of sexually dimorphic trait growth in horned beetles. Beetles in the family Scarabaeidae have various types of horns on their heads and thoraces, and the shape, size, number, and location of these horns are highly diversified within the group. In addition, many scarab beetle horns are sexually dimorphic. The acquisition of these evolutionarily novel horns, and the mechanisms for the diversification of these structures is an interesting question. To address this question, we focused on the rhinoceros beetle Tripoxylus dichotomus. Here we identified the exact developmental timepoints during which the morphological sexual dimorphism of horn primordia appears, estimated the onset of the developmental program for sexually dimorphic horn formation driven by doublesex, and revealed that doublesex regulates different aspects of cell activities during horn formation depending on particular spatiotemporal developmental contexts. Our study provides insights into regulatory shifts in these mechanisms during the evolution of sexually dimorphic traits in horned beetles.
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Affiliation(s)
- Shinichi Morita
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki, Japan
| | - Toshiya Ando
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki, Japan
- Department of Basic Biology, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), 38 Nishigonaka, Myodaiji, Okazaki, Japan
| | - Akiteru Maeno
- Mammalian Genetics Laboratory, Genetic Strains Research Center, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Takeshi Mizutani
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki, Japan
| | - Mutsuki Mase
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki, Japan
- Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya, Japan
| | - Shuji Shigenobu
- Department of Basic Biology, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), 38 Nishigonaka, Myodaiji, Okazaki, Japan
- NIBB Core Research Facilities, National Institute for Basic Biology, 38 Nishigonaka Myodaiji, Okazaki, Japan
| | - Teruyuki Niimi
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki, Japan
- Department of Basic Biology, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), 38 Nishigonaka, Myodaiji, Okazaki, Japan
- Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya, Japan
- * E-mail:
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Facial masculinity does not appear to be a condition-dependent male ornament and does not reflect MHC heterozygosity in humans. Proc Natl Acad Sci U S A 2019; 116:1633-1638. [PMID: 30647112 DOI: 10.1073/pnas.1808659116] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Recent studies have called into question the idea that facial masculinity is a condition-dependent male ornament that indicates immunocompetence in humans. We add to this growing body of research by calculating an objective measure of facial masculinity/femininity using 3D images in a large sample (n = 1,233) of people of European ancestry. We show that facial masculinity is positively correlated with adult height in both males and females. However, facial masculinity scales with growth similarly in males and females, suggesting that facial masculinity is not exclusively a male ornament, as male ornaments are typically more sensitive to growth in males compared with females. Additionally, we measured immunocompetence via heterozygosity at the major histocompatibility complex (MHC), a widely-used genetic marker of immunity. We show that, while height is positively correlated with MHC heterozygosity, facial masculinity is not. Thus, facial masculinity does not reflect immunocompetence measured by MHC heterozygosity in humans. Overall, we find no support for the idea that facial masculinity is a condition-dependent male ornament that has evolved to indicate immunocompetence.
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50
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Schwab DB, Casasa S, Moczek AP. On the Reciprocally Causal and Constructive Nature of Developmental Plasticity and Robustness. Front Genet 2019; 9:735. [PMID: 30687394 PMCID: PMC6335315 DOI: 10.3389/fgene.2018.00735] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 12/22/2018] [Indexed: 01/29/2023] Open
Abstract
Exposure to environmental variation is a characteristic feature of normal development, one that organisms can respond to during their lifetimes by actively adjusting or maintaining their phenotype in order to maximize fitness. Plasticity and robustness have historically been studied by evolutionary biologists through quantitative genetic and reaction norm approaches, while more recent efforts emerging from evolutionary developmental biology have begun to characterize the molecular and developmental genetic underpinnings of both plastic and robust trait formation. In this review, we explore how our growing mechanistic understanding of plasticity and robustness is beginning to force a revision of our perception of both phenomena, away from our conventional view of plasticity and robustness as opposites along a continuum and toward a framework that emphasizes their reciprocal, constructive, and integrative nature. We do so in three sections. Following an introduction, the first section looks inward and reviews the genetic, epigenetic, and developmental mechanisms that enable organisms to sense and respond to environmental conditions, maintaining and adjusting trait formation in the process. In the second section, we change perspective and look outward, exploring the ways in which organisms reciprocally shape their environments in ways that influence trait formation, and do so through the lens of behavioral plasticity, niche construction, and host-microbiota interactions. In the final section, we revisit established plasticity and robustness concepts in light of these findings, and highlight research opportunities to further advance our understanding of the causes, mechanisms, and consequences of these ubiquitous, and interrelated, phenomena.
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