1
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Erlenbach T, Haynes L, Fish O, Beveridge J, Giambrone S, Reed LK, Dyer KA, Scott Chialvo CH. Investigating the phylogenetic history of toxin tolerance in mushroom-feeding Drosophila. Ecol Evol 2023; 13:e10736. [PMID: 38099137 PMCID: PMC10719611 DOI: 10.1002/ece3.10736] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 11/01/2023] [Accepted: 11/02/2023] [Indexed: 12/17/2023] Open
Abstract
Understanding how and when key novel adaptations evolved is a central goal of evolutionary biology. Within the immigrans-tripunctata radiation of Drosophila, many mushroom-feeding species are tolerant of host toxins, such as cyclopeptides, that are lethal to nearly all other eukaryotes. In this study, we used phylogenetic and functional approaches to investigate the evolution of cyclopeptide tolerance in the immigrans-tripunctata radiation of Drosophila. First, we inferred the evolutionary relationships among 48 species in this radiation using 978 single copy orthologs. Our results resolved previous incongruities within species groups across the phylogeny. Second, we expanded on previous studies of toxin tolerance by assaying 16 of these species for tolerance to α-amanitin and found that six of them could develop on diet with toxin. Finally, we asked how α-amanitin tolerance might have evolved across the immigrans-tripunctata radiation, and inferred that toxin tolerance was ancestral in mushroom-feeding Drosophila and subsequently lost multiple times. Our findings expand our understanding of toxin tolerance across the immigrans-tripunctata radiation and emphasize the uniqueness of toxin tolerance in this adaptive radiation and the complexity of biochemical adaptations.
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Affiliation(s)
| | - Lauren Haynes
- Department of Biological SciencesUniversity of AlabamaTuscaloosaAlabamaUSA
| | - Olivia Fish
- Department of Biological SciencesUniversity of AlabamaTuscaloosaAlabamaUSA
| | - Jordan Beveridge
- Department of Biological SciencesUniversity of AlabamaTuscaloosaAlabamaUSA
| | | | - Laura K. Reed
- Department of Biological SciencesUniversity of AlabamaTuscaloosaAlabamaUSA
| | - Kelly A. Dyer
- Department of GeneticsUniversity of GeorgiaAthensGeorgiaUSA
| | - Clare H. Scott Chialvo
- Department of Biological SciencesUniversity of AlabamaTuscaloosaAlabamaUSA
- Department of BiologyAppalachian State UniversityBooneNorth CarolinaUSA
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2
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Fukutomi Y, Takahashi A, Koshikawa S. Thermal plasticity of wing size and wing spot size in Drosophila guttifera. Dev Genes Evol 2023; 233:77-89. [PMID: 37332038 PMCID: PMC10746645 DOI: 10.1007/s00427-023-00705-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 05/31/2023] [Indexed: 06/20/2023]
Abstract
Thermal plasticity of melanin pigmentation patterns in Drosophila species has been studied as a model to investigate developmental mechanisms of phenotypic plasticity. The developmental process of melanin pigmentation patterns on wings of Drosophila is divided into two parts, prepattern specification during the pupal period and wing vein-dependent transportation of melanin precursors after eclosion. Which part can be affected by thermal changes? To address this question, we used polka-dotted melanin spots on wings of Drosophila guttifera, whose spot areas are specified by wingless morphogen. In this research, we reared D. guttifera at different temperatures to test whether wing spots show thermal plasticity. We found that wing size becomes larger at lower temperature and that different spots have different reaction norms. Furthermore, we changed the rearing temperature in the middle of the pupal period and found that the most sensitive developmental periods for wing size and spot size are different. The results suggest that the size control mechanisms for the thermal plasticity of wing size and spot size are independent. We also found that the most sensitive stage for spot size was part of the pupal period including stages at which wingless is expressed in the polka-dotted pattern. Therefore, it is suggested that temperature change might affect the prepattern specification process and might not affect transportation through wing veins.
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Affiliation(s)
- Yuichi Fukutomi
- Department of Evolution and Ecology, University of California, Davis, One Shields Ave, Davis, CA, 95616, USA.
- Department of Biological Sciences, Tokyo Metropolitan University, 1-1 Minamiosawa, Hachioji, 192-0397, Japan.
| | - Aya Takahashi
- Department of Biological Sciences, Tokyo Metropolitan University, 1-1 Minamiosawa, Hachioji, 192-0397, Japan
- Research Center for Genomics and Bioinformatics, Tokyo Metropolitan University, 1-1 Minamiosawa, Hachioji, 192-0397, Japan
| | - Shigeyuki Koshikawa
- Graduate School of Environmental Science, Hokkaido University, N10W5, Kita-Ku, Sapporo, Hokkaido, 060-0810, Japan
- Faculty of Environmental Earth Science, Hokkaido University, N10W5, Kita-Ku, Sapporo, Hokkaido, 060-0810, Japan
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3
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Robinson CD, Hale MD, Wittman TN, Cox CL, John-Alder HB, Cox RM. Species differences in hormonally mediated gene expression underlie the evolutionary loss of sexually dimorphic coloration in Sceloporus lizards. J Hered 2023; 114:637-653. [PMID: 37498153 DOI: 10.1093/jhered/esad046] [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: 04/19/2023] [Accepted: 07/24/2023] [Indexed: 07/28/2023] Open
Abstract
Phenotypic sexual dimorphism often involves the hormonal regulation of sex-biased expression for underlying genes. However, it is generally unknown whether the evolution of hormonally mediated sexual dimorphism occurs through upstream changes in tissue sensitivity to hormone signals, downstream changes in responsiveness of target genes, or both. Here, we use comparative transcriptomics to explore these possibilities in 2 species of Sceloporus lizards exhibiting different patterns of sexual dichromatism. Sexually dimorphic S. undulatus develops blue and black ventral coloration in response to testosterone, while sexually monomorphic S. virgatus does not, despite exhibiting similar sex differences in circulating testosterone levels. We administered testosterone implants to juveniles of each species and used RNAseq to quantify gene expression in ventral skin. Transcriptome-wide responses to testosterone were stronger in S. undulatus than in S. virgatus, suggesting species differences in tissue sensitivity to this hormone signal. Species differences in the expression of genes for androgen metabolism and sex hormone-binding globulin were consistent with this idea, but expression of the androgen receptor gene was higher in S. virgatus, complicating this interpretation. Downstream of androgen signaling, we found clear species differences in hormonal responsiveness of genes related to melanin synthesis, which were upregulated by testosterone in S. undulatus, but not in S. virgatus. Collectively, our results indicate that hormonal regulation of melanin synthesis pathways contributes to the development of sexual dimorphism in S. undulatus, and that changes in the hormonal responsiveness of these genes in S. virgatus contribute to the evolutionary loss of ventral coloration.
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Affiliation(s)
| | - Matthew D Hale
- University of Virginia, Department of Biology, Charlottesville, VA, United States
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, United States
- Henry M. Jackson Foundation for the Advancement of Military Medicine Inc., Bethesda, MD, United States
| | - Tyler N Wittman
- University of Virginia, Department of Biology, Charlottesville, VA, United States
| | - Christian L Cox
- Florida International University, Department of Biological Sciences and Institute of Environment, Miami, FL, United States
| | - Henry B John-Alder
- Rutgers University, Department of Ecology, Evolution, and Natural Resources, New Brunswick, NJ, United States
| | - Robert M Cox
- University of Virginia, Department of Biology, Charlottesville, VA, United States
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4
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Mo WZ, Li ZM, Deng XM, Chen AL, Ritchie MG, Yang DJ, He ZB, Toda MJ, Wen SY. Divergence and correlated evolution of male wing spot and courtship display between Drosophila nepalensis and D. trilutea. INSECT SCIENCE 2022; 29:1445-1460. [PMID: 34939317 DOI: 10.1111/1744-7917.12994] [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: 09/06/2021] [Revised: 11/25/2021] [Accepted: 11/29/2021] [Indexed: 06/14/2023]
Abstract
Male-specific wing spots are usually associated with wing displays in the courtship behavior of Drosophila and may play important roles in sexual selection. Two closely related species, D. nepalensis and D. trilutea, differ in wing spots and scissoring behavior. Here, we compare male morphological characters, pigmentation intensity of male wing spots, wing-scissoring behavior, courtship songs, and reproductive isolation between 2 species. F1 fertile females and sterile males result from the cross between females of D. nepalensis and males of D. trilutea. The pigmentation of wing spots is significantly weaker in D. trilutea than in D. nepalensis and the F1 hybrid. Males scissor both wings in front of the female during courtship, with a posture spreading wings more widely, and at a faster frequency in D. nepalensis than in D. trilutea and the F1s. Males of D. trilutea vibrate wings to produce 2 types (A and B) of pulse songs, whereas D. nepalensis and the F1s sing only type B songs. The incidence of wing vibration and scissoring during courtship suggests that wing vibration is essential but scissoring is a facultative courtship element for successful mating in both species. The association between the darker wing spots with more elaborate scissoring might be the consequence of correlated evolution of these traits in D. nepalensis; however, D. trilutea retains wing scissoring during courtship despite having weaker pigmentation of wing spots. The genetic architecture of 2 traits differs in the F1s, consistent with maternal or sex-linked effects for spots but nonadditive effects for scissoring.
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Affiliation(s)
- Wen-Zhou Mo
- Department of Entomology, College of Plant Protection, South China Agricultural University, Guangzhou, China
| | - Zhuo-Miao Li
- Department of Entomology, College of Plant Protection, South China Agricultural University, Guangzhou, China
| | - Xiang-Mei Deng
- Department of Entomology, College of Plant Protection, South China Agricultural University, Guangzhou, China
| | - Ai-Li Chen
- Department of Entomology, College of Plant Protection, South China Agricultural University, Guangzhou, China
| | | | - De-Jun Yang
- Acoustics Laboratory, Guangdong Institute of Metrology, South China National Centre of Metrology, Guangzhou, China
| | - Zhuo-Bin He
- Acoustics Laboratory, Guangdong Institute of Metrology, South China National Centre of Metrology, Guangzhou, China
| | | | - Shuo-Yang Wen
- Department of Entomology, College of Plant Protection, South China Agricultural University, Guangzhou, China
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5
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Giraud G, Paul R, Duffraisse M, Khan S, Shashidhara LS, Merabet S. Developmental Robustness: The Haltere Case in Drosophila. Front Cell Dev Biol 2021; 9:713282. [PMID: 34368162 PMCID: PMC8343187 DOI: 10.3389/fcell.2021.713282] [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: 05/22/2021] [Accepted: 06/30/2021] [Indexed: 11/24/2022] Open
Abstract
Developmental processes have to be robust but also flexible enough to respond to genetic and environmental variations. Different mechanisms have been described to explain the apparent antagonistic nature of developmental robustness and plasticity. Here, we present a “self-sufficient” molecular model to explain the development of a particular flight organ that is under the control of the Hox gene Ultrabithorax (Ubx) in the fruit fly Drosophila melanogaster. Our model is based on a candidate RNAi screen and additional genetic analyses that all converge to an autonomous and cofactor-independent mode of action for Ubx. We postulate that this self-sufficient molecular mechanism is possible due to an unusually high expression level of the Hox protein. We propose that high dosage could constitute a so far poorly investigated molecular strategy for allowing Hox proteins to both innovate and stabilize new forms during evolution.
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Affiliation(s)
| | | | | | - Soumen Khan
- Indian Institute of Science Education and Research (IISER), Pune, India
| | - L S Shashidhara
- Indian Institute of Science Education and Research (IISER), Pune, India.,Ashoka University, Sonipat, India
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6
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Popadić A, Tsitlakidou D. Regional patterning and regulation of melanin pigmentation in insects. Curr Opin Genet Dev 2021; 69:163-170. [PMID: 34087530 DOI: 10.1016/j.gde.2021.05.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 05/04/2021] [Accepted: 05/10/2021] [Indexed: 10/21/2022]
Abstract
Insects display an immense diversity in melanin pigmentation, which is generated by the interplay between the regulatory genes (that provide general patterning information) and effector genes (that provide coloration of the pattern). However, recent studies encompassing several different orders (Hemiptera, Blattodea, Coleoptera, and Lepidoptera) have shown that knockdowns of melanin producing genes alone can generate distinct region-specific patterns. This review surveys the most recent studies to further document the regional patterning of effector genes, and highlights the new advances and their implications for future research.
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Affiliation(s)
- Aleksandar Popadić
- Biological Sciences Department, Wayne State University, Detroit, MI 48202, USA.
| | - Despina Tsitlakidou
- Biological Sciences Department, Wayne State University, Detroit, MI 48202, USA
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7
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Niida T, Koshikawa S. No evidence for contribution of sexually monomorphic wing pigmentation pattern to mate choice in
Drosophila guttifera. Ethology 2021. [DOI: 10.1111/eth.13157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Takuma Niida
- Graduate School of Environmental Science Hokkaido University Sapporo Japan
| | - Shigeyuki Koshikawa
- Graduate School of Environmental Science Hokkaido University Sapporo Japan
- Faculty of Environmental Earth Science Hokkaido University Sapporo Japan
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8
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The color pattern inducing gene wingless is expressed in specific cell types of campaniform sensilla of a polka-dotted fruit fly, Drosophila guttifera. Dev Genes Evol 2021; 231:85-93. [PMID: 33774724 DOI: 10.1007/s00427-021-00674-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 03/15/2021] [Indexed: 12/16/2022]
Abstract
A polka-dotted fruit fly, Drosophila guttifera, has a unique pigmentation pattern on its wings and is used as a model for evo-devo studies exploring the mechanism of evolutionary gain of novel traits. In this species, a morphogen-encoding gene, wingless, is expressed in species-specific positions and induces a unique pigmentation pattern. To produce some of the pigmentation spots on wing veins, wingless is thought to be expressed in developing campaniform sensillum cells, but it was unknown which of the four cell types there express(es) wingless. Here we show that two of the cell types, dome cells and socket cells, express wingless, as indicated by in situ hybridization together with immunohistochemistry. This is a unique case in which non-neuronal SOP (sensory organ precursor) progeny cells produce Wingless as an inducer of pigmentation pattern formation. Our finding opens a path to clarifying the mechanism of evolutionary gain of a unique wingless expression pattern by analyzing gene regulation in dome cells and socket cells.
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9
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Drosophila melanogaster Mitochondrial Carriers: Similarities and Differences with the Human Carriers. Int J Mol Sci 2020; 21:ijms21176052. [PMID: 32842667 PMCID: PMC7504413 DOI: 10.3390/ijms21176052] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 08/19/2020] [Accepted: 08/19/2020] [Indexed: 12/15/2022] Open
Abstract
Mitochondrial carriers are a family of structurally related proteins responsible for the exchange of metabolites, cofactors and nucleotides between the cytoplasm and mitochondrial matrix. The in silico analysis of the Drosophila melanogaster genome has highlighted the presence of 48 genes encoding putative mitochondrial carriers, but only 20 have been functionally characterized. Despite most Drosophila mitochondrial carrier genes having human homologs and sharing with them 50% or higher sequence identity, D. melanogaster genes display peculiar differences from their human counterparts: (1) in the fruit fly, many genes encode more transcript isoforms or are duplicated, resulting in the presence of numerous subfamilies in the genome; (2) the expression of the energy-producing genes in D. melanogaster is coordinated from a motif known as Nuclear Respiratory Gene (NRG), a palindromic 8-bp sequence; (3) fruit-fly duplicated genes encoding mitochondrial carriers show a testis-biased expression pattern, probably in order to keep a duplicate copy in the genome. Here, we review the main features, biological activities and role in the metabolism of the D. melanogaster mitochondrial carriers characterized to date, highlighting similarities and differences with their human counterparts. Such knowledge is very important for obtaining an integrated view of mitochondrial function in D. melanogaster metabolism.
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10
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Suzuki T, Koshikawa S. Enhancer functions underlying morphological diversity. Dev Growth Differ 2020; 62:263-264. [PMID: 32479642 DOI: 10.1111/dgd.12685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Takayuki Suzuki
- Avian Bioscience Research Center, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
| | - Shigeyuki Koshikawa
- Faculty of Environmental Earth Science, Hokkaido University, Sapporo, Japan.,Graduate School of Environmental Science, Hokkaido University, Sapporo, Japan
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11
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Fukutomi Y, Kondo S, Toyoda A, Shigenobu S, Koshikawa S. Transcriptome analysis reveals wingless regulates neural development and signaling genes in the region of wing pigmentation of a polka-dotted fruit fly. FEBS J 2020; 288:99-110. [PMID: 32307851 DOI: 10.1111/febs.15338] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 03/14/2020] [Accepted: 04/17/2020] [Indexed: 11/26/2022]
Abstract
How evolutionary novelties have arisen is one of the central questions in evolutionary biology. Preexisting gene regulatory networks or signaling pathways have been shown to be co-opted for building novel traits in several organisms. However, the structure of entire gene regulatory networks and evolutionary events of gene co-option for emergence of a novel trait are poorly understood. In this study, to explore the genetic and molecular bases of the novel wing pigmentation pattern of a polka-dotted fruit fly (Drosophila guttifera), we performed de novo genome sequencing and transcriptome analyses. As a result, we comprehensively identified the genes associated with the pigmentation pattern. Furthermore, we revealed that 151 of these associated genes were positively or negatively regulated by wingless, a master regulator of wing pigmentation. Genes for neural development, Wnt signaling, Dpp signaling, and effectors (such as enzymes) for melanin pigmentation were included among these 151 genes. None of the known regulatory genes that regulate pigmentation pattern formation in other fruit fly species were included. Our results suggest that the novel pigmentation pattern of a polka-dotted fruit fly might have emerged through multistep co-options of multiple gene regulatory networks, signaling pathways, and effector genes, rather than recruitment of one large gene circuit.
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Affiliation(s)
- Yuichi Fukutomi
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Japan
| | - Shu Kondo
- Invertebrate Genetics Laboratory, National Institute of Genetics, Mishima, Japan
| | - Atsushi Toyoda
- Comparative Genomics Laboratory, Department of Genomics and Evolutionary Biology, National Institute of Genetics, Mishima, Japan
| | - Shuji Shigenobu
- Functional Genomics Facility, National Institute for Basic Biology, Okazaki, Japan
| | - Shigeyuki Koshikawa
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Japan.,Faculty of Environmental Earth Science, Hokkaido University, Sapporo, Japan
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12
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Shittu M, Steenwinkel T, Koshikawa S, Werner T. The Making of Transgenic Drosophila guttifera. Methods Protoc 2020; 3:E31. [PMID: 32349368 PMCID: PMC7359701 DOI: 10.3390/mps3020031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 04/25/2020] [Accepted: 04/26/2020] [Indexed: 12/24/2022] Open
Abstract
The complex color patterns on the wings and body of Drosophila guttifera (D. guttifera) are emerging as model systems for studying evolutionary and developmental processes. Studies regarding these processes depend on overexpression and downregulation of developmental genes, which ultimately rely upon an effective transgenic system. Methods describing transgenesis in Drosophila melanogaster (D. melanogaster) have been reported in several studies, but they cannot be applied to D. guttifera due to the low egg production rate and the delicacy of the eggs. In this protocol, we describe extensively a comprehensive method used for generating transgenic D. guttifera. Using the protocol described here, we are able to establish transgenic lines, identifiable by the expression of enhanced green fluorescent protein (EGFP) in the eye disks of D. guttifera larvae. The entire procedure, from injection to screening for transgenic larvae, can be completed in approximately 30 days and should be relatively easy to adapt to other non-model Drosophila species, for which no white-eyed mutants exist.
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Affiliation(s)
- Mujeeb Shittu
- Department of Biological Sciences, Michigan Technological University, Houghton, MI 49931, USA; (M.S.); (T.S.)
| | - Tessa Steenwinkel
- Department of Biological Sciences, Michigan Technological University, Houghton, MI 49931, USA; (M.S.); (T.S.)
| | - Shigeyuki Koshikawa
- Faculty of Environmental Earth Science, Hokkaido University, N10W5, Kita-ku, Sapporo, Hokkaido 060-0810, Japan
- Graduate School of Environmental Science, Hokkaido University, N10W5, Kita-ku, Sapporo, Hokkaido 060-0810, Japan
| | - Thomas Werner
- Department of Biological Sciences, Michigan Technological University, Houghton, MI 49931, USA; (M.S.); (T.S.)
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13
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Koshikawa S. Evolution of wing pigmentation in Drosophila: Diversity, physiological regulation, and cis-regulatory evolution. Dev Growth Differ 2020; 62:269-278. [PMID: 32171022 PMCID: PMC7384037 DOI: 10.1111/dgd.12661] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 03/04/2020] [Accepted: 03/04/2020] [Indexed: 12/20/2022]
Abstract
Fruit flies (Drosophila and its close relatives, or “drosophilids”) are a group that includes an important model organism, Drosophila melanogaster, and also very diverse species distributed worldwide. Many of these species have black or brown pigmentation patterns on their wings, and have been used as material for evo‐devo research. Pigmentation patterns are thought to have evolved rapidly compared with body plans or body shapes; hence they are advantageous model systems for studying evolutionary gains of traits and parallel evolution. Various groups of drosophilids, including genus Idiomyia (Hawaiian Drosophila), have a variety of pigmentations, ranging from simple black pigmentations around crossveins to a single antero‐distal spot and a more complex mottled pattern. Pigmentation patterns are sometimes obviously used for sexual displays; however, in some cases they may have other functions. The process of wing formation in Drosophila, the general mechanism of pigmentation formation, and the transport of substances necessary for pigmentation, including melanin precursors, through wing veins are summarized here. Lastly, the evolution of the expression of genes regulating pigmentation patterns, the role of cis‐regulatory regions, and the conditions required for the evolutionary emergence of pigmentation patterns are discussed. Future prospects for research on the evolution of wing pigmentation pattern formation in drosophilids are presented, particularly from the point of view of how they compare with other studies of the evolution of new traits.
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Affiliation(s)
- Shigeyuki Koshikawa
- Faculty of Environmental Earth Science, Hokkaido University, Sapporo, Japan.,Graduate School of Environmental Science, Hokkaido University, Sapporo, Japan
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