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Developmental dynamics of butterfly wings: real-time in vivo whole-wing imaging of twelve butterfly species. Sci Rep 2018; 8:16848. [PMID: 30442931 PMCID: PMC6237780 DOI: 10.1038/s41598-018-34990-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 10/24/2018] [Indexed: 01/13/2023] Open
Abstract
Colour pattern development of butterfly wings has been studied from several different approaches. However, developmental changes in the pupal wing tissues have rarely been documented visually. In this study, we recorded real-time developmental changes of the pupal whole wings of 9 nymphalid, 2 lycaenid, and 1 pierid species in vivo, from immediately after pupation to eclosion, using the forewing-lift method. The developmental period was roughly divided into four sequential stages. At the very early stage, the wing tissue was transparent, but at the second stage, it became semi-transparent and showed dynamic peripheral adjustment and slow low-frequency contractions. At this stage, the wing peripheral portion diminished in size, but simultaneously, the ventral epithelium expanded in size. Likely because of scale growth, the wing tissue became deeply whitish at the second and third stages, followed by pigment deposition and structural colour expression at the fourth stage. Some red or yellow (light-colour) areas that emerged early were “overpainted” by expanding black areas, suggesting the coexistence of two morphogenic signals in some scale cells. The discal spot emerged first in some nymphalid species, as though it organised the entire development of colour patterns. These results indicated the dynamic wing developmental processes common in butterflies.
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Beldade P, Peralta CM. Developmental and evolutionary mechanisms shaping butterfly eyespots. CURRENT OPINION IN INSECT SCIENCE 2017; 19:22-29. [PMID: 28521939 DOI: 10.1016/j.cois.2016.10.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 10/20/2016] [Accepted: 10/24/2016] [Indexed: 06/07/2023]
Abstract
Butterfly eyespots are visually compelling models to study the reciprocal interactions between evolutionary and developmental processes that shape phenotypic variation. They are evolutionarily diversified, ecologically relevant, and developmentally tractable, and have made key contributions to linking genotype, development, phenotype and fitness. Advances in the availability of analytical tools (e.g. gene editing and visualization techniques) and resources (e.g. genomic and transcriptomic data) are boosting the detailed dissection of the mechanisms underlying eyespot development and evolution. Here, we review current knowledge on the ecology, development, and evolution of butterfly eyespots, with focus on recent advances. We also highlight a number of unsolved mysteries in our understanding of the patterns and processes underlying the diversification of these structures.
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Affiliation(s)
- Patrícia Beldade
- Instituto Gulbenkian de Ciência, Oeiras, Portugal; UMR5174, University of Toulouse, France.
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Ohno Y, Iguchi A, Shinzato C, Inoue M, Suzuki A, Sakai K, Nakamura T. An aposymbiotic primary coral polyp counteracts acidification by active pH regulation. Sci Rep 2017; 7:40324. [PMID: 28098180 PMCID: PMC5241827 DOI: 10.1038/srep40324] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Accepted: 12/05/2016] [Indexed: 01/12/2023] Open
Abstract
Corals build their skeletons using extracellular calcifying fluid located in the tissue-skeleton interface. However, the mechanism by which corals control the transport of calcium and other ions from seawater and the mechanism of constant alkalization of calcifying fluid are largely unknown. To address these questions, we performed direct pH imaging at calcification sites (subcalicoblastic medium, SCM) to visualize active pH upregulation in live aposymbiotic primary coral polyps treated with HCl-acidified seawater. Active alkalization was observed in all individuals using vital staining method while the movement of HPTS and Alexa Fluor to SCM suggests that certain ions such as H+ could diffuse via a paracellular pathway to SCM. Among them, we discovered acid-induced oscillations in the pH of SCM (pHSCM), observed in 24% of polyps examined. In addition, we discovered acid-induced pH up-regulation waves in 21% of polyps examined, which propagated among SCMs after exposure to acidified seawater. Our results showed that corals can regulate pHSCM more dynamically than was previously believed. These observations will have important implications for determining how corals regulate pHSCM during calcification. We propose that corals can sense ambient seawater pH via their innate pH-sensitive systems and regulate pHSCM using several unknown pH-regulating ion transporters that coordinate with multicellular signaling occurring in coral tissue.
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Affiliation(s)
- Yoshikazu Ohno
- Marine and Environmental Sciences Course, Graduate School of Engineering and Science, University of the Ryukyus, Senbaru 1, Nishihara, Okinawa 903-0213, Japan
| | - Akira Iguchi
- Department of Bioresources Engineering, National Institute of Technology, Okinawa College, 905 Henoko, Nago, Okinawa 905-2192, Japan
| | - Chuya Shinzato
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa 904-0495, Japan
| | - Mayuri Inoue
- Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Okayama 700-8530, Japan
| | - Atsushi Suzuki
- Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8567, Japan
| | - Kazuhiko Sakai
- Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, 3422 Sesoko, Motobu, Okinawa 905-0227, Japan
| | - Takashi Nakamura
- Marine and Environmental Sciences Course, Graduate School of Engineering and Science, University of the Ryukyus, Senbaru 1, Nishihara, Okinawa 903-0213, Japan
- Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, 3422 Sesoko, Motobu, Okinawa 905-0227, Japan
- Japan Science and Technology Agency (JST)/Japan International Cooperation Agency (JICA) SATREPS, Tokyo, Japan
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Dhungel B, Ohno Y, Matayoshi R, Iwasaki M, Taira W, Adhikari K, Gurung R, Otaki JM. Distal-less induces elemental color patterns in Junonia butterfly wings. ZOOLOGICAL LETTERS 2016; 2:4. [PMID: 26937287 PMCID: PMC4774158 DOI: 10.1186/s40851-016-0040-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 02/17/2016] [Indexed: 05/09/2023]
Abstract
BACKGROUND The border ocellus, or eyespot, is a conspicuous color pattern element in butterfly wings. For two decades, it has been hypothesized that transcription factors such as Distal-less (Dll) are responsible for eyespot pattern development in butterfly wings, based on their expression in the prospective eyespots. In particular, it has been suggested that Dll is a determinant for eyespot size. However, functional evidence for this hypothesis has remained incomplete, due to technical difficulties. RESULTS Here, we show that ectopically expressed Dll induces ectopic elemental color patterns in the adult wings of the blue pansy butterfly, Junonia orithya (Lepidoptera, Nymphalidae). Using baculovirus-mediated gene transfer, we misexpressed Dll protein fused with green fluorescent protein (GFP) in pupal wings, resulting in ectopic color patterns, but not the formation of intact eyespots. Induced changes included clusters of black and orange scales (a basic feature of eyespot patterns), black and gray scales, and inhibition of cover scale development. In contrast, ectopic expression of GFP alone did not induce any color pattern changes using the same baculovirus-mediated gene transfer system. CONCLUSIONS These results suggest that Dll plays an instructive role in the development of color pattern elements in butterfly wings, although Dll alone may not be sufficient to induce a complete eyespot. This study thus experimentally supports the hypothesis of Dll function in eyespot development.
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Affiliation(s)
- Bidur Dhungel
- The BCPH Unit of Molecular Physiology, Department of Chemistry, Biology and Marine Science, University of the Ryukyus, Okinawa, 903-0213 Japan
| | - Yoshikazu Ohno
- The BCPH Unit of Molecular Physiology, Department of Chemistry, Biology and Marine Science, University of the Ryukyus, Okinawa, 903-0213 Japan
| | - Rie Matayoshi
- The BCPH Unit of Molecular Physiology, Department of Chemistry, Biology and Marine Science, University of the Ryukyus, Okinawa, 903-0213 Japan
| | - Mayo Iwasaki
- The BCPH Unit of Molecular Physiology, Department of Chemistry, Biology and Marine Science, University of the Ryukyus, Okinawa, 903-0213 Japan
| | - Wataru Taira
- The BCPH Unit of Molecular Physiology, Department of Chemistry, Biology and Marine Science, University of the Ryukyus, Okinawa, 903-0213 Japan
| | - Kiran Adhikari
- The BCPH Unit of Molecular Physiology, Department of Chemistry, Biology and Marine Science, University of the Ryukyus, Okinawa, 903-0213 Japan
| | - Raj Gurung
- The BCPH Unit of Molecular Physiology, Department of Chemistry, Biology and Marine Science, University of the Ryukyus, Okinawa, 903-0213 Japan
| | - Joji M. Otaki
- The BCPH Unit of Molecular Physiology, Department of Chemistry, Biology and Marine Science, University of the Ryukyus, Okinawa, 903-0213 Japan
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Ohno Y, Otaki JM. Spontaneous long-range calcium waves in developing butterfly wings. BMC DEVELOPMENTAL BIOLOGY 2015; 15:17. [PMID: 25888365 PMCID: PMC4445562 DOI: 10.1186/s12861-015-0067-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Accepted: 01/15/2015] [Indexed: 11/11/2022]
Abstract
Background Butterfly wing color patterns emerge as the result of a regular arrangement of scales produced by epithelial scale cells at the pupal stage. These color patterns and scale arrangements are coordinated throughout the wing. However, the mechanism by which the development of scale cells is controlled across the entire wing remains elusive. In the present study, we used pupal wings of the blue pansy butterfly, Junonia orithya, which has distinct eyespots, to examine the possible involvement of Ca2+ waves in wing development. Results Here, we demonstrate that the developing pupal wing tissue of the blue pansy butterfly displayed spontaneous low-frequency Ca2+ waves in vivo that propagated slowly over long distances. Some waves appeared to be released from the immediate peripheries of the prospective eyespot and discal spot, though it was often difficult to identify the specific origins of these waves. Physical damage, which is known to induce ectopic eyespots, led to the radiation of Ca2+ waves from the immediate periphery of the damaged site. Thapsigargin, which is a specific inhibitor of Ca2+-ATPases in the endoplasmic reticulum, induced an acute increase in cytoplasmic Ca2+ levels and halted the spontaneous Ca2+ waves. Additionally, thapsigargin-treated wings showed incomplete scale development as well as other scale and color pattern abnormalities. Conclusions We identified a novel form of Ca2+ waves, spontaneous low-frequency slow waves, which travel over exceptionally long distances. Our results suggest that spontaneous Ca2+ waves play a critical role in the coordinated development of scale arrangements and possibly in color pattern formation in butterflies. Electronic supplementary material The online version of this article (doi:10.1186/s12861-015-0067-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Yoshikazu Ohno
- The BCPH Unit of Molecular Physiology, Department of Chemistry, Biology and Marine Science, Faculty of Science, University of the Ryukyus, Nishihara, Okinawa, 903-0213, Japan.
| | - Joji M Otaki
- The BCPH Unit of Molecular Physiology, Department of Chemistry, Biology and Marine Science, Faculty of Science, University of the Ryukyus, Nishihara, Okinawa, 903-0213, Japan.
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Iwata M, Ohno Y, Otaki JM. Real-time in vivo imaging of butterfly wing development: revealing the cellular dynamics of the pupal wing tissue. PLoS One 2014; 9:e89500. [PMID: 24586829 PMCID: PMC3931798 DOI: 10.1371/journal.pone.0089500] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Accepted: 01/20/2014] [Indexed: 12/25/2022] Open
Abstract
Butterfly wings are covered with regularly arranged single-colored scales that are formed at the pupal stage. Understanding pupal wing development is therefore crucial to understand wing color pattern formation. Here, we successfully employed real-time in vivo imaging techniques to observe pupal hindwing development over time in the blue pansy butterfly, Junonia orithya. A transparent sheet of epithelial cells that were not yet regularly arranged was observed immediately after pupation. Bright-field imaging and autofluorescent imaging revealed free-moving hemocytes and tracheal branches of a crinoid-like structure underneath the epithelium. The wing tissue gradually became gray-white, epithelial cells were arranged regularly, and hemocytes disappeared, except in the bordering lacuna, after which scales grew. The dynamics of the epithelial cells and scale growth were also confirmed by fluorescent imaging. Fluorescent in vivo staining further revealed that these cells harbored many mitochondria at the surface of the epithelium. Organizing centers for the border symmetry system were apparent immediately after pupation, exhibiting a relatively dark optical character following treatment with fluorescent dyes, as well as in autofluorescent images. The wing tissue exhibited slow and low-frequency contraction pulses with a cycle of approximately 10 to 20 minutes, mainly occurring at 2 to 3 days postpupation. The pulses gradually became slower and weaker and eventually stopped. The wing tissue area became larger after contraction, which also coincided with an increase in the autofluorescence intensity that might have been caused by scale growth. Examination of the pattern of color development revealed that the black pigment was first deposited in patches in the central areas of an eyespot black ring and a parafocal element. These results of live in vivo imaging that covered wide wing area for a long time can serve as a foundation for studying the cellular dynamics of living wing tissues in butterflies.
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Affiliation(s)
- Masaki Iwata
- The BCPH Unit of Molecular Physiology, Department of Chemistry, Biology and Marine Science, Faculty of Science, University of the Ryukyus, Nishihara, Okinawa, Japan
| | - Yoshikazu Ohno
- The BCPH Unit of Molecular Physiology, Department of Chemistry, Biology and Marine Science, Faculty of Science, University of the Ryukyus, Nishihara, Okinawa, Japan
| | - Joji M. Otaki
- The BCPH Unit of Molecular Physiology, Department of Chemistry, Biology and Marine Science, Faculty of Science, University of the Ryukyus, Nishihara, Okinawa, Japan
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System-dependent regulations of colour-pattern development: a mutagenesis study of the pale grass blue butterfly. Sci Rep 2014; 3:2379. [PMID: 23917124 PMCID: PMC3753731 DOI: 10.1038/srep02379] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Accepted: 07/23/2013] [Indexed: 12/22/2022] Open
Abstract
Developmental studies on wing colour patterns have been performed in nymphalid butterflies, but efficient genetic manipulations, including mutagenesis, have not been well established. Here, we have performed mutagenesis experiments in a lycaenid butterfly, the pale grass blue Zizeeria maha, to produce colour-pattern mutants. We fed the P-generation larvae an artificial diet containing the mutagen ethyl methane sulfonate (EMS), and the F1- and F2-generation adults showed various aberrant colour patterns: dorsoventral transformation, anterioposterior background colouration gap, weak contrast, disarrangement of spots, reduction of the size of spots, loss of spots, fusion of spots, and ectopic spots. Among them, the disarrangement, reduction, and loss of spots were likely produced by the coordinated changes of many spots of a single wing around the discal spot in a system-dependent manner, demonstrating the existence of the central symmetry system. The present study revealed multiple genetic regulations for system-dependent and wing-wide colour-pattern determination in lycaenid butterflies.
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Kelley JL, Fitzpatrick JL, Merilaita S. Spots and stripes: ecology and colour pattern evolution in butterflyfishes. Proc Biol Sci 2013; 280:20122730. [PMID: 23427170 PMCID: PMC3619473 DOI: 10.1098/rspb.2012.2730] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2012] [Accepted: 01/25/2013] [Indexed: 11/12/2022] Open
Abstract
The incredible diversity of colour patterns in coral reef fishes has intrigued biologists for centuries. Yet, despite the many proposed explanations for this diversity in coloration, definitive tests of the role of ecological factors in shaping the evolution of particular colour pattern traits are absent. Patterns such as spots and eyespots (spots surrounded by concentric rings of contrasting colour) have often been assumed to function for predator defence by mimicking predators' enemies' eyes, deflecting attacks or intimidating predators, but the evolutionary processes underlying these functions have never been addressed. Striped body patterns have been suggested to serve for both social communication and predator defence, but the impact of ecological constraints remains unclear. We conducted the first comparative analysis of colour pattern diversity in butterflyfishes (Family: Chaetodontidae), fishes with conspicuous spots, eyespots and wide variation in coloration. Using a dated molecular phylogeny of 95 species (approx. 75% of the family), we tested whether spots and eyespots have evolved characteristics that are consistent with their proposed defensive function and whether the presence of spots and body stripes is linked with species' body length, dietary complexity, habitat diversity or social behaviour. Contrary to our expectations, spots and eyespots appeared relatively recently in butterflyfish evolution and are highly evolutionarily labile, suggesting that they are unlikely to have played an important part in the evolutionary history of the group. Striped body patterns showed correlated evolution with a number of ecological factors including habitat type, sociality and dietary complexity. Our findings question the prevailing view that eyespots are an evolutionary response to predation pressure, providing a valuable counter example to the role of these markings as revealed in other taxa.
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Affiliation(s)
- Jennifer L Kelley
- Centre for Evolutionary Biology/Neuroecology Group, School of Animal Biology, The University of Western Australia, Nedlands, WA 6009, Australia.
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Of dogs and cows: a quasi-artificial selection scenario. Heredity (Edinb) 2012; 110:94. [PMID: 23032309 DOI: 10.1038/hdy.2012.64] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Otaki JM. Color Pattern Analysis of Nymphalid Butterfly Wings: Revision of the Nymphalid Groundplan. Zoolog Sci 2012; 29:568-76. [DOI: 10.2108/zsj.29.568] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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