1
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Fu X, Zhu X. Key homeobox transcription factors regulate the development of the firefly's adult light organ and bioluminescence. Nat Commun 2024; 15:1736. [PMID: 38443352 PMCID: PMC10914744 DOI: 10.1038/s41467-024-45559-7] [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: 06/17/2023] [Accepted: 01/26/2024] [Indexed: 03/07/2024] Open
Abstract
Adult fireflies exhibit unique flashing courtship signals, emitted by specialized light organs, which develop mostly independently from larval light organs during the pupal stage. The mechanisms of adult light organ development have not been thoroughly studied until now. Here we show that key homeobox transcription factors AlABD-B and AlUNC-4 regulate the development of adult light organs and bioluminescence in the firefly Aquatica leii. Interference with the expression of AlAbd-B and AlUnc-4 genes results in undeveloped or non-luminescent adult light organs. AlABD-B regulates AlUnc-4, and they interact with each other. AlABD-B and AlUNC-4 activate the expression of the luciferase gene AlLuc1 and some peroxins. Four peroxins are involved in the import of AlLUC1 into peroxisomes. Our study provides key insights into the development of adult light organs and flash signal control in fireflies.
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Affiliation(s)
- Xinhua Fu
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.
| | - Xinlei Zhu
- Firefly Conservation Research Centre, Wuhan, 430070, China
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2
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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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3
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Guo H, Liu XZ, Long GJ, Gong LL, Zhang MQ, Ma YF, Hull JJ, Dewer Y, He M, He P. Functional characterization of developmentally critical genes in the white-backed planthopper: Efficacy of nanoparticle-based dsRNA sprays for pest control. PEST MANAGEMENT SCIENCE 2023; 79:1048-1061. [PMID: 36325939 DOI: 10.1002/ps.7271] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Revised: 09/30/2022] [Accepted: 11/03/2022] [Indexed: 06/16/2023]
Abstract
BACKGROUND Epidermal growth factor receptor (EGFR), zinc finger homeodomain-2 (zfh-2), Abdominal-A (Abd-A), and Abdominal-B (Abd-B) regulate the growth and development of the insect abdomen. However, their potential roles in pest control have not been fully assessed. The development of insecticide resistance to multiple chemistries in the white-backed planthopper (WBPH), a major pest of rice, has prompted interest in novel pest control approaches that are ecologically friendly. Although pest management approaches based on double-stranded RNA (dsRNA)-mediated RNA interference (RNAi) have potential, their susceptibility to degradation limits large-scale field applications. These limitations, however, can be overcome with nanoparticle-dsRNA complexes that have greater environmental stability and improved cellular uptake. RESULTS In this study, at 5 days post-injection, transcripts for the four gene targets were reduced relative to controls and all of the experimental groups exhibited significant phenotypic defects and increased mortality. To evaluate the potential of these gene targets for field applications, a nanocarrier-dsRNA spray delivery system was assessed for RNAi efficacy. At 11 days post-spray, significant phenotypic defects and increased mortality were observed in all experimental groups. CONCLUSION Taken together, the results confirm the suitability of the target genes (SfEGFR, Sfzfh-2, SfAbd-A, and SfAbd-B) for pest management and demonstrate the efficacy of the nanocarrier spray system for inducing RNAi-mediated knockdown. As such, the study lays the foundation for the further development and optimization of this technology for large-scale field applications. © 2022 Society of Chemical Industry.
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Affiliation(s)
- Huan Guo
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Guiyang, P. R. China
| | - Xuan-Zheng Liu
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Guiyang, P. R. China
| | - Gui-Jun Long
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Guiyang, P. R. China
| | - Lang-Lang Gong
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Guiyang, P. R. China
| | - Meng-Qi Zhang
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Guiyang, P. R. China
| | - Yun-Feng Ma
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Guiyang, P. R. China
| | - J Joe Hull
- Pest Management and Biocontrol Research Unit, US Arid Land Agricultural Research Center, USDA Agricultural Research Services, Maricopa, AZ, USA
| | - Youssef Dewer
- Phytotoxicity Research Department, Central Agricultural Pesticide Laboratory, Agricultural Research Center, Giza, Egypt
| | - Ming He
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Guiyang, P. R. China
| | - Peng He
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Guiyang, P. R. China
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4
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Liu BP, Ding G, Miao Y, Hua BZ. The Hox gene Abdominal-B regulates the appendage development during the embryogenesis of scorpionflies. INSECT MOLECULAR BIOLOGY 2022; 31:609-619. [PMID: 35575115 DOI: 10.1111/imb.12790] [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: 12/31/2021] [Accepted: 05/12/2022] [Indexed: 06/15/2023]
Abstract
The Homeotic Complex (Hox) genes encode conserved homeodomain transcription factors that specify segment identity and appendage morphology along the antero-posterior axis in bilaterian animals. The Hox gene Abdominal-B (Abd-B) is mainly expressed in the posterior segments of the abdomen and plays an important role in insect organogenesis. In Mecoptera, the potential function of this gene remains unclear yet. Here, we performed a de novo transcriptome assembly and identified an Abd-B ortholog in the scorpionfly Panorpa liui. Quantitative real-time reverse transcription PCR showed that Abd-B expression increased gradually in embryos 76 h post oviposition, and was mainly present in the more posterior abdominal segments. Embryonic RNA interference of Abd-B resulted in a set of abnormalities, including developmental arrest, malformed suckers and misspecification of posterior segment identity. These results suggest that Abd-B is required for the proper development of the posterior abdomen. Furthermore, in Abd-B RNAi embryos, the expression of the appendage marker Distal-less (Dll) was up-regulated and was additionally present on abdominal segments IX and X compared with wild embryos, suggesting that scorpionfly Abd-B may act to suppress proleg development and has gained the ability to repress Dll expression on the more posterior abdominal segments. This study provides additional information on both the functional and evolutionary roles of Abd-B across different insects.
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Affiliation(s)
- Bing-Peng Liu
- Key Laboratory of Plant Protection Resources and Pest Management, Ministry of Education, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China
| | - Guo Ding
- Key Laboratory of Plant Protection Resources and Pest Management, Ministry of Education, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China
| | - Ying Miao
- Key Laboratory of Plant Protection Resources and Pest Management, Ministry of Education, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China
| | - Bao-Zhen Hua
- Key Laboratory of Plant Protection Resources and Pest Management, Ministry of Education, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China
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5
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Chen SJ, Liu XY, Zhang JL, Yang ZN, Xu HJ. Abdominal-B contributes to abdominal identity in the brown planthopper, Nilaparvata lugens (Hemiptera: Delphacidae). INSECT MOLECULAR BIOLOGY 2022; 31:447-456. [PMID: 35278009 DOI: 10.1111/imb.12771] [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: 10/08/2021] [Revised: 01/23/2022] [Accepted: 03/07/2022] [Indexed: 06/14/2023]
Abstract
The homeotic complex gene Abdominal-B (Abd-B) is involved in regulating the development of posterior abdomens and has been extensively studied in holometabolous insects. However, the function of Abd-B in hemimetabolous insects is not fully understood. Here, we functionally characterize an Abd-B homologue in the brown planthopper (BPH), Nilaparvata lugens. The full-length cDNA of the N. lugens Abd-B homologue (NlAbd-B) is 2334 nt, with an open reading frame of 1113 bp. NlAbd-B has the highest expression level at the egg stage relative to the nymphal and adult stages and is mainly expressed in the fourth to the ninth abdominal segment of embryos. RNA interference (RNAi)-mediated knockdown of NlAbd-B in nymphs disrupted the development of genitalia both in females and males and caused a genitalia-to-leg transformation. Parental RNAi of NlAbd-B in both female and male adults caused an extra abdominal segment in offspring nymphs, while parental RNAi of the N. lugens abdominal-A homologue in both female and males adults led to embryos with leg-like appendages on the second to the eighth abdominal segment. These findings suggest that NlAbd-B plays a pivotal role in genital development and posterior abdominal patterning and thus highlight the conservational role of Abd-B in holometabolous and hemimetabolous insects.
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Affiliation(s)
- Sun-Jie Chen
- Institute of Insect Sciences, Zhejiang University, Hangzhou, China
- State Key Laboratory of Rice Biology, Zhejiang University, Hangzhou, China
- Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Zhejiang University, Hangzhou, China
| | - Xin-Yang Liu
- Institute of Insect Sciences, Zhejiang University, Hangzhou, China
- State Key Laboratory of Rice Biology, Zhejiang University, Hangzhou, China
- Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Zhejiang University, Hangzhou, China
| | - Jin-Li Zhang
- Institute of Insect Sciences, Zhejiang University, Hangzhou, China
- State Key Laboratory of Rice Biology, Zhejiang University, Hangzhou, China
- Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Zhejiang University, Hangzhou, China
| | - Zhang-Nv Yang
- Key Laboratory of Vaccine, Prevention and Control of Infectious Diseases of Zhejiang Province, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Hai-Jun Xu
- Institute of Insect Sciences, Zhejiang University, Hangzhou, China
- State Key Laboratory of Rice Biology, Zhejiang University, Hangzhou, China
- Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Zhejiang University, Hangzhou, China
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Mariano-Martins P, Monfardini RD, Lo-Man-Hung N, Torres TT. Evidence of positive selection on six spider developmental genes. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART B, MOLECULAR AND DEVELOPMENTAL EVOLUTION 2022; 338:314-322. [PMID: 34985811 DOI: 10.1002/jez.b.23119] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 11/16/2021] [Accepted: 12/04/2021] [Indexed: 06/14/2023]
Abstract
Spiders constitute more than 49,000 described species distributed all over the world, and all ecological environments. Their order, Araneae, is defined by a set of characteristics with no parallel among their arachnid counterparts (e.g., spinnerets, silk glands, chelicerae that inoculate venom, among others). Changes in developmental pathways often underlie the evolution of morphological synapomorphies, and as such spiders are a promising model to study the role of developmental genes in the origin of evolutionary novelties. With that in mind, we investigated changes in the evolutionary regime of a set of six developmental genes, using spiders as our model. The genes were mainly chosen for their roles in spinneret ontogeny, yet they are pleiotropic, and it is likely that the origins of other unique morphological phenotypes are also linked to changes in their sequences. Our results indicate no great differences in the selective pressures on those genes when comparing spiders to other arachnids, but a few site-specific positive selection evidence were found in the Araneae lineage. These findings lead us to new insights on spider evolution that are to be further tested.
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Affiliation(s)
- Pedro Mariano-Martins
- Department of Genetics and Evolutionary Biology, Institute of Biosciences, University of São Paulo, São Paulo - SP, Brazil
| | - Raquel Dietsche Monfardini
- Department of Genetics and Evolutionary Biology, Institute of Biosciences, University of São Paulo, São Paulo - SP, Brazil
| | - Nancy Lo-Man-Hung
- Department of Genetics and Evolutionary Biology, Institute of Biosciences, University of São Paulo, São Paulo - SP, Brazil
| | - Tatiana Teixeira Torres
- Department of Genetics and Evolutionary Biology, Institute of Biosciences, University of São Paulo, São Paulo - SP, Brazil
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7
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Oba Y, Schultz DT. Firefly genomes illuminate the evolution of beetle bioluminescent systems. CURRENT OPINION IN INSECT SCIENCE 2022; 50:100879. [PMID: 35091104 DOI: 10.1016/j.cois.2022.100879] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 12/30/2021] [Accepted: 01/20/2022] [Indexed: 06/14/2023]
Abstract
Fireflies are one of the best-known bioluminescent organisms, and the reaction mechanism and ecological utility of bioluminescence have been well-studied. Genome assemblies of six species of bioluminescent beetles have recently been published. These studies have focused on the evolution of novelties; luciferase, and the biosynthesis of luciferin and defensive chemicals. For example, clustering of the luciferase gene with acyl-CoA synthetase genes on a chromosome in luminous beetle genomes suggests the involvement of tandem gene duplications and neofunctionalization during the evolution of beetle bioluminescence. Several candidate genes for critical roles in beetle bioluminescence have been identified, but their functional analyses are still ongoing. The establishment of a long-term mass-rearing system and strain will be the key for the post-genome research on bioluminescent beetles. Lastly, the application of contemporary chromosome-scale genome assembly techniques to luminous beetles will help resolve outstanding evolutionary questions, such as how many times bioluminescence evolved in this clade.
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Affiliation(s)
- Yuichi Oba
- Department of Environmental Biology, Chubu University, Kasugai 487-8501, Japan.
| | - Darrin T Schultz
- Monterey Bay Aquarium Research Institute, Moss Landing, CA 95039, United States
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8
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Riley WB, Rosa SP, Lima da Silveira LF. A comprehensive review and call for studies on firefly larvae. PeerJ 2021; 9:e12121. [PMID: 34616609 PMCID: PMC8459732 DOI: 10.7717/peerj.12121] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 08/16/2021] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND Fireflies (Coleoptera: Lampyridae) are commonly recognized by adult traits, such as a soft exoskeleton, lanterns and associated glow and flash patterns, but their larval stage is far less appreciated. However, fireflies spend most of their lives as larvae, and adults of most species rely solely on resources previously obtained. Therefore, studying the immature stages is imperative towards a comprehensive understanding of fireflies. This paper reviews and indicates key gaps in the biology of firefly larvae based on available literature. METHODOLOGY We reviewed the literature on firefly larvae to identify key issues and important taxonomic, geographic, and subject biases and gaps. RESULTS We found 376 papers that included information on firefly larvae. Only 139 species in 47 genera across eight of eleven lampyrid subfamilies have been studied during larval stages. These numbers reveal a staggering gap, since 94% of species and over half of the genera of fireflies were never studied in a crucial stage of their life cycle. Most studies on firefly larvae focus on two subfamilies (Luciolinae and Lampyrinae) in four zoogeographic regions (Sino-Japanese, Oriental, Nearctic, and Palearctic), whereas the other subfamilies and regions remain largely unstudied. These studies mainly dealt with morphology and behavior, other subjects remaining greatly understudied by comparison, including habitats, life cycle, physiology and interactions. CONCLUSIONS Together, these literature biases and gaps highlight how little is known about firefly larvae, and warmly invite basic and applied research, in the field and in the lab, to overcome these limitations and improve our understanding of firefly biology to better preserve them.
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Affiliation(s)
- William B. Riley
- Department of Biology, Western Carolina University, Cullowhee, NC, United States of America
| | - Simone Policena Rosa
- Instituto de Recursos Naturais, Universidade Federal de Itajubá, Itajubá, Minas Gerais, Brazil
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9
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Novikova EL, Kulakova MA. There and Back Again: Hox Clusters Use Both DNA Strands. J Dev Biol 2021; 9:28. [PMID: 34287306 PMCID: PMC8293171 DOI: 10.3390/jdb9030028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/06/2021] [Accepted: 07/13/2021] [Indexed: 12/25/2022] Open
Abstract
Bilaterian animals operate the clusters of Hox genes through a rich repertoire of diverse mechanisms. In this review, we will summarize and analyze the accumulated data concerning long non-coding RNAs (lncRNAs) that are transcribed from sense (coding) DNA strands of Hox clusters. It was shown that antisense regulatory RNAs control the work of Hox genes in cis and trans, participate in the establishment and maintenance of the epigenetic code of Hox loci, and can even serve as a source of regulatory peptides that switch cellular energetic metabolism. Moreover, these molecules can be considered as a force that consolidates the cluster into a single whole. We will discuss the examples of antisense transcription of Hox genes in well-studied systems (cell cultures, morphogenesis of vertebrates) and bear upon some interesting examples of antisense Hox RNAs in non-model Protostomia.
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Affiliation(s)
- Elena L. Novikova
- Department of Embryology, St. Petersburg State University, Universitetskaya nab. 7–9, 199034 Saint Petersburg, Russia;
- Laboratory of Evolutionary Morphology, Zoological Institute RAS, Universitetskaya nab. 1, 199034 Saint Petersburg, Russia
| | - Milana A. Kulakova
- Department of Embryology, St. Petersburg State University, Universitetskaya nab. 7–9, 199034 Saint Petersburg, Russia;
- Laboratory of Evolutionary Morphology, Zoological Institute RAS, Universitetskaya nab. 1, 199034 Saint Petersburg, Russia
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10
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Zhang R, He J, Dong Z, Liu G, Yin Y, Zhang X, Li Q, Ren Y, Yang Y, Liu W, Chen X, Xia W, Duan K, Hao F, Lin Z, Yang J, Chang Z, Zhao R, Wan W, Lu S, Peng Y, Ge S, Wang W, Li X. Genomic and experimental data provide new insights into luciferin biosynthesis and bioluminescence evolution in fireflies. Sci Rep 2020; 10:15882. [PMID: 32985577 PMCID: PMC7522259 DOI: 10.1038/s41598-020-72900-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 09/09/2020] [Indexed: 02/08/2023] Open
Abstract
Fireflies are among the most charismatic insects for their spectacular bioluminescence, but the origin and evolution of bioluminescence remain elusive. Especially, the genic basis of luciferin (D-luciferin) biosynthesis and light patterns is largely unknown. Here, we present the high-quality reference genomes of two fireflies Lamprigera yunnana (1053 Mb) and Abscondita terminalis (501 Mb) with great differences in both morphology and luminous behavior. We sequenced the transcriptomes and proteomes of luminous organs of two species. We created the CRISPR/Cas9-induced mutants of Abdominal B gene without luminous organs in the larvae of A. terminalis and sequenced the transcriptomes of mutants and wild-types. Combining gene expression analyses with comparative genomics, we propose a more complete luciferin synthesis pathway, and confirm the convergent evolution of bioluminescence in insects. Using experiments, the function of the firefly acyl-CoA thioesterase (ACOT1) to convert L-luciferin to D-luciferin was validated for the first time. Comparisons of three-dimension reconstruction of luminous organs and their differentially expressed genes among two species suggest that two positive genes in the calcium signaling pathway and structural difference of luminous organs may play an important role in the evolution of flash pattern. Altogether, our results provide important resources for further exploring bioluminescence in insects.
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Affiliation(s)
- Ru Zhang
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an, 710072, Shaanxi, China
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650223, Yunnan, China
| | - Jinwu He
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an, 710072, Shaanxi, China
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650223, Yunnan, China
| | - Zhiwei Dong
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650223, Yunnan, China
| | - Guichun Liu
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650223, Yunnan, China
| | - Yuan Yin
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an, 710072, Shaanxi, China
| | - Xinying Zhang
- Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Qi Li
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an, 710072, Shaanxi, China
| | - Yandong Ren
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650223, Yunnan, China
| | - Yongzhi Yang
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an, 710072, Shaanxi, China
| | - Wei Liu
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650223, Yunnan, China
| | - Xianqing Chen
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an, 710072, Shaanxi, China
| | - Wenhao Xia
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an, 710072, Shaanxi, China
| | - Kang Duan
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650223, Yunnan, China
| | - Fei Hao
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an, 710072, Shaanxi, China
| | - Zeshan Lin
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an, 710072, Shaanxi, China
| | - Jie Yang
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an, 710072, Shaanxi, China
| | - Zhou Chang
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650223, Yunnan, China
| | - Ruoping Zhao
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650223, Yunnan, China
| | - Wenting Wan
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an, 710072, Shaanxi, China
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650223, Yunnan, China
| | - Sihan Lu
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an, 710072, Shaanxi, China
| | - Yanqiong Peng
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, 666303, Yunnan, China
| | - Siqin Ge
- Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
| | - Wen Wang
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an, 710072, Shaanxi, China.
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650223, Yunnan, China.
- Center for Excellence in Animal Evolution and Genetics, Kunming, 650223, Yunnan, China.
| | - Xueyan Li
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650223, Yunnan, China.
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11
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Game M, Smith FW. Loss of intermediate regions of perpendicular body axes contributed to miniaturization of tardigrades. Proc Biol Sci 2020; 287:20201135. [PMID: 33043863 DOI: 10.1098/rspb.2020.1135] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Tardigrades have a miniaturized body plan. Miniaturization in tardigrades is associated with the loss of several organ systems and an intermediate region of their anteroposterior (AP) axis. However, how miniaturization has affected tardigrade legs is unclear. In arthropods and in onychophorans, the leg gap genes are expressed in regionalized proximodistal (PD) patterns in the legs. Functional studies indicate that these genes regulate growth in their respective expression domains and establish PD identities, partly through mutually antagonistic regulatory interactions. Here, we investigated the expression patterns of tardigrade orthologs of the leg gap genes. Rather than being restricted to a proximal leg region, as in arthropods and onychophorans, we detected coexpression of orthologues of homothorax and extradenticle broadly across the legs of the first three trunk segments in the tardigrade Hypsibius exemplaris. We could not identify a dachshund orthologue in tardigrade genomes, a gene that is expressed in an intermediate region of developing legs in arthropods and onychophorans, suggesting that this gene was lost in the tardigrade lineage. We detected Distal-less expression broadly across all developing leg buds in H. exemplaris embryos, unlike in arthropods and onychophorans, in which it exhibits a distally restricted expression domain. The broad expression patterns of the remaining leg gap genes in H. exemplaris legs may reflect the loss of dachshund and the accompanying loss of an intermediate region of the legs in the tardigrade lineage. We propose that the loss of intermediate regions of both the AP and PD body axes contributed to miniaturization of Tardigrada.
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Affiliation(s)
- Mandy Game
- Biology Department, University of North Florida, USA
| | - Frank W Smith
- Biology Department, University of North Florida, USA
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12
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Mariano-Martins P, Lo-Man-Hung N, Torres TT. Evolution of Spiders and Silk Spinning: Mini Review of the Morphology, Evolution, and Development of Spiders’ Spinnerets. Front Ecol Evol 2020. [DOI: 10.3389/fevo.2020.00109] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
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13
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Hox genes limit germ cell formation in the short germ insect Gryllus bimaculatus. Proc Natl Acad Sci U S A 2019; 116:16430-16435. [PMID: 31346080 DOI: 10.1073/pnas.1816024116] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Hox genes are conserved transcription factor-encoding genes that specify the identity of body regions in bilaterally symmetrical animals. In the cricket Gryllus bimaculatus, a member of the hemimetabolous insect group Orthoptera, the induction of a subset of mesodermal cells to form the primordial germ cells (PGCs) is restricted to the second through the fourth abdominal segments (A2 to A4). In numerous insect species, the Hox genes Sex-combs reduced (Scr), Antennapedia (Antp), Ultrabithorax (Ubx), and abdominal-A (abd-A) jointly regulate the identities of middle and posterior body segments, suggesting that these genes may restrict PGC formation to specific abdominal segments in G. bimaculatus Here we show that reducing transcript levels of some or all of these Hox genes results in supernumerary and/or ectopic PGCs, either individually or in segment-specific combinations, suggesting that the role of these Hox genes is to limit PGC development with respect to their number, segmental location, or both. These data provide evidence of a role for this ancient group of genes in PGC development.
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14
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Linz DM, Hu Y, Moczek AP. The origins of novelty from within the confines of homology: the developmental evolution of the digging tibia of dung beetles. Proc Biol Sci 2019; 286:20182427. [PMID: 30963933 PMCID: PMC6408602 DOI: 10.1098/rspb.2018.2427] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 01/23/2019] [Indexed: 11/12/2022] Open
Abstract
Understanding the origin of novel complex traits is among the most fundamental goals in evolutionary biology. The most widely used definition of novelty in evolution assumes the absence of homology, yet where homology ends and novelty begins is increasingly difficult to parse as evo devo continuously revises our understanding of what constitutes homology. Here, we executed a case study to explore the earliest stages of innovation by examining the tibial teeth of tunnelling dung beetles. Tibial teeth are a morphologically modest innovation, composed of relatively simple body wall projections and contained fully within the fore tibia, a leg segment whose own homology status is unambiguous. We first demonstrate that tibial teeth aid in multiple digging behaviours. We then show that the developmental evolution of tibial teeth was dominated by the redeployment of locally pre-existing gene networks. At the same time, we find that even at this very early stage of innovation, at least two genes that ancestrally function in embryonic patterning and thus entirely outside the spatial and temporal context of leg formation, have already become recruited to help shape the formation of tibial teeth. Our results suggest a testable model for how developmental evolution scaffolds innovation.
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15
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Zee PC, Velicer GJ. Parallel emergence of negative epistasis across experimental lineages. Evolution 2017; 71:1088-1095. [PMID: 28128449 DOI: 10.1111/evo.13190] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 01/05/2017] [Indexed: 01/03/2023]
Abstract
Epistatic interactions can greatly impact evolutionary phenomena, particularly the process of adaptation. Here, we leverage four parallel experimentally evolved lineages to study the emergence and trajectories of epistatic interactions in the social bacterium Myxococcus xanthus. A social gene (pilA) necessary for effective group swarming on soft agar had been deleted from the common ancestor of these lineages. During selection for competitiveness at the leading edge of growing colonies, two lineages evolved qualitatively novel mechanisms for greatly increased swarming on soft agar, whereas the other two lineages evolved relatively small increases in swarming. By reintroducing pilA into different genetic backgrounds along the four lineages, we tested whether parallel lineages showed similar patterns of epistasis. In particular, we tested whether a pattern of negative epistasis between accumulating mutations and pilA previously found in the fastest lineage would be found only in the two evolved lineages with the fastest and most striking swarming phenotypes, or rather was due to common epistatic structure across all lineages arising from the generic fixation of adaptive mutations. Our analysis reveals the emergence of negative epistasis across all four independent lineages. Further, we present results showing that the observed negative epistasis is not due exclusively to evolving populations approaching a maximum phenotypic value that inherently limits positive effects of pilA reintroduction, but rather involves direct antagonistic interactions between accumulating mutations and the reintroduced social gene.
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Affiliation(s)
- Peter C Zee
- Department of Biology, California State University, Northridge, California.,Department of Biology, Indiana University, Bloomington, Indiana
| | - Gregory J Velicer
- Department of Biology, Indiana University, Bloomington, Indiana.,Department of Environmental Systems Sciences, ETH Zürich, Zürich, Switzerland
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16
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Vongsangnak W, Chumnanpuen P, Sriboonlert A. Transcriptome analysis reveals candidate genes involved in luciferin metabolism in Luciola aquatilis (Coleoptera: Lampyridae). PeerJ 2016; 4:e2534. [PMID: 27761329 PMCID: PMC5068357 DOI: 10.7717/peerj.2534] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Accepted: 09/06/2016] [Indexed: 12/31/2022] Open
Abstract
Bioluminescence, which living organisms such as fireflies emit light, has been studied extensively for over half a century. This intriguing reaction, having its origins in nature where glowing insects can signal things such as attraction or defense, is now widely used in biotechnology with applications of bioluminescence and chemiluminescence. Luciferase, a key enzyme in this reaction, has been well characterized; however, the enzymes involved in the biosynthetic pathway of its substrate, luciferin, remains unsolved at present. To elucidate the luciferin metabolism, we performed a de novo transcriptome analysis using larvae of the firefly species, Luciola aquatilis. Here, a comparative analysis is performed with the model coleopteran insect Tribolium casteneum to elucidate the metabolic pathways in L. aquatilis. Based on a template luciferin biosynthetic pathway, combined with a range of protein and pathway databases, and various prediction tools for functional annotation, the candidate genes, enzymes, and biochemical reactions involved in luciferin metabolism are proposed for L. aquatilis. The candidate gene expression is validated in the adult L. aquatilis using reverse transcription PCR (RT-PCR). This study provides useful information on the bio-production of luciferin in the firefly and will benefit to future applications of the valuable firefly bioluminescence system.
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Affiliation(s)
- Wanwipa Vongsangnak
- Department of Zoology, Kasetsart University, Bangkok, Thailand; Computational Biomodelling Laboratory for Agricultural Science and Technology (CBLAST), Faculty of Science, Kasetsart University, Bangkok, Thailand
| | - Pramote Chumnanpuen
- Department of Zoology, Kasetsart University, Bangkok, Thailand; Computational Biomodelling Laboratory for Agricultural Science and Technology (CBLAST), Faculty of Science, Kasetsart University, Bangkok, Thailand
| | - Ajaraporn Sriboonlert
- Department of Genetics, Kasetsart University, Bangkok, Thailand; Centre for Advanced Studies in Tropical Natural Resources, Kasetsart University, Bangkok, Thailand
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17
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Busey HA, Zattara EE, Moczek AP. Conservation, Innovation, and Bias: Embryonic Segment Boundaries Position Posterior, but Not Anterior, Head Horns in Adult Beetles. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2016; 326:271-9. [DOI: 10.1002/jez.b.22682] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 05/30/2016] [Accepted: 06/03/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Hannah A. Busey
- Department of Biology Indiana University Bloomington Indiana
| | | | - Armin P. Moczek
- Department of Biology Indiana University Bloomington Indiana
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18
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Abstract
Hox proteins are a deeply conserved group of transcription factors originally defined for their critical roles in governing segmental identity along the antero-posterior (AP) axis in
Drosophila. Over the last 30 years, numerous data generated in evolutionarily diverse taxa have clearly shown that changes in the expression patterns of these genes are closely associated with the regionalization of the AP axis, suggesting that
Hox genes have played a critical role in the evolution of novel body plans within Bilateria. Despite this deep functional conservation and the importance of these genes in AP patterning, key questions remain regarding many aspects of
Hox biology. In this commentary, we highlight recent reports that have provided novel insight into the origins of the mammalian
Hox cluster, the role of
Hox genes in the generation of a limbless body plan, and a novel putative mechanism in which
Hox genes may encode specificity along the AP axis. Although the data discussed here offer a fresh perspective, it is clear that there is still much to learn about
Hox biology and the roles it has played in the evolution of the Bilaterian body plan.
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Affiliation(s)
- Steven M Hrycaj
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, 48109-2200, USA
| | - Deneen M Wellik
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, 48109-2200, USA; Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, Michigan, 48109-2200, USA
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19
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Peterson T, Müller GB. Phenotypic Novelty in EvoDevo: The Distinction Between Continuous and Discontinuous Variation and Its Importance in Evolutionary Theory. Evol Biol 2016; 43:314-335. [PMID: 27512237 PMCID: PMC4960286 DOI: 10.1007/s11692-016-9372-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Accepted: 01/29/2016] [Indexed: 10/25/2022]
Abstract
The introduction of novel phenotypic structures is one of the most significant aspects of organismal evolution. Yet the concept of evolutionary novelty is used with drastically different connotations in various fields of research, and debate exists about whether novelties represent features that are distinct from standard forms of phenotypic variation. This article contrasts four separate uses for novelty in genetics, population genetics, morphology, and behavioral science, before establishing how novelties are used in evolutionary developmental biology (EvoDevo). In particular, it is detailed how an EvoDevo-specific research approach to novelty produces insight distinct from other fields, gives the concept explanatory power with predictive capacities, and brings new consequences to evolutionary theory. This includes the outlining of research strategies that draw attention to productive areas of inquiry, such as threshold dynamics in development. It is argued that an EvoDevo-based approach to novelty is inherently mechanistic, treats the phenotype as an agent with generative potential, and prompts a distinction between continuous and discontinuous variation in evolutionary theory.
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Affiliation(s)
- Tim Peterson
- Department of Theoretical Biology, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
| | - Gerd B. Müller
- Department of Theoretical Biology, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
- The KLI Institute, Martinstrasse 12, 3400 Klosterneuburg, Austria
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20
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Macagno ALM, Moczek AP. Appendage-patterning genes regulate male and female copulatory structures in horned beetles. Evol Dev 2016; 17:248-53. [PMID: 26174101 DOI: 10.1111/ede.12129] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Explaining the extraordinarily rapid diversification of insect copulatory structures has been a longstanding objective in evolutionary biology. However, remarkably little is known about the developmental genetic underpinnings of their formation. Furthermore, recent work has questioned whether male genitalic structures in beetles are serially homologous to appendages, or even homologous to the genitalia of other orders. Using RNA interference, we demonstrate that several cardinal appendage-patterning genes regulate the formation of copulatory structures in Onthophagus beetles of both sexes. These results are in strong disagreement with previous findings in the model beetle species Tribolium castaneum, but congruent with earlier studies in true bugs and flies. Our results support the hypotheses that genitalic development is largely conserved across insect orders, and that genitalia constitute serial appendage homologues. Moreover, we identify two patterning genes with striking phenotypic effects in both sexes. In these cases, the affected structures are known to interact functionally during copulation, but are not homologous to each other. This suggests that shared developmental regulation of male and female copulatory structures may extend beyond components related by descent to those related by function.
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Affiliation(s)
- Anna L M Macagno
- Department of Biology, Indiana University, 915 East Third Street, 102 Myers Hall, Bloomington, Indiana, 47405-7107, USA
| | - Armin P Moczek
- Department of Biology, Indiana University, 915 East Third Street, 102 Myers Hall, Bloomington, Indiana, 47405-7107, USA
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21
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Torrens-Spence MP, Fallon TR, Weng JK. A Workflow for Studying Specialized Metabolism in Nonmodel Eukaryotic Organisms. Methods Enzymol 2016; 576:69-97. [PMID: 27480683 DOI: 10.1016/bs.mie.2016.03.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Eukaryotes contain a diverse tapestry of specialized metabolites, many of which are of significant pharmaceutical and industrial importance to humans. Nevertheless, exploration of specialized metabolic pathways underlying specific chemical traits in nonmodel eukaryotic organisms has been technically challenging and historically lagged behind that of the bacterial systems. Recent advances in genomics, metabolomics, phylogenomics, and synthetic biology now enable a new workflow for interrogating unknown specialized metabolic systems in nonmodel eukaryotic hosts with greater efficiency and mechanistic depth. This chapter delineates such workflow by providing a collection of state-of-the-art approaches and tools, ranging from multiomics-guided candidate gene identification to in vitro and in vivo functional and structural characterization of specialized metabolic enzymes. As already demonstrated by several recent studies, this new workflow opens up a gateway into the largely untapped world of natural product biochemistry in eukaryotes.
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Affiliation(s)
- M P Torrens-Spence
- Whitehead Institute for Biomedical Research, Cambridge, MA, United States
| | - T R Fallon
- Whitehead Institute for Biomedical Research, Cambridge, MA, United States; Massachusetts Institute of Technology, Cambridge, MA, United States
| | - J K Weng
- Whitehead Institute for Biomedical Research, Cambridge, MA, United States; Massachusetts Institute of Technology, Cambridge, MA, United States.
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22
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Camino EM, Butts JC, Ordway A, Vellky JE, Rebeiz M, Williams TM. The evolutionary origination and diversification of a dimorphic gene regulatory network through parallel innovations in cis and trans. PLoS Genet 2015; 11:e1005136. [PMID: 25835988 PMCID: PMC4383587 DOI: 10.1371/journal.pgen.1005136] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Accepted: 03/10/2015] [Indexed: 01/15/2023] Open
Abstract
The origination and diversification of morphological characteristics represents a key problem in understanding the evolution of development. Morphological traits result from gene regulatory networks (GRNs) that form a web of transcription factors, which regulate multiple cis-regulatory element (CRE) sequences to control the coordinated expression of differentiation genes. The formation and modification of GRNs must ultimately be understood at the level of individual regulatory linkages (i.e., transcription factor binding sites within CREs) that constitute the network. Here, we investigate how elements within a network originated and diversified to generate a broad range of abdominal pigmentation phenotypes among Sophophora fruit flies. Our data indicates that the coordinated expression of two melanin synthesis enzymes, Yellow and Tan, recently evolved through novel CRE activities that respond to the spatial patterning inputs of Hox proteins and the sex-specific input of Bric-à-brac transcription factors. Once established, it seems that these newly evolved activities were repeatedly modified by evolutionary changes in the network’s trans-regulators to generate large-scale changes in pigment pattern. By elucidating how yellow and tan are connected to the web of abdominal trans-regulators, we discovered that the yellow and tan abdominal CREs are composed of distinct regulatory inputs that exhibit contrasting responses to the same Hox proteins and Hox cofactors. These results provide an example in which CRE origination underlies a recently evolved novel trait, and highlights how coordinated expression patterns can evolve in parallel through the generation of unique regulatory linkages. The genomic content of regulatory genes such as transcription factors is surprisingly conserved between diverse animal species, raising the paradox of how new traits emerge, and are subsequently modified and lost. In this study we make a connection between the developmental basis for the formation of a fruit fly trait and the evolutionary basis for that trait’s origin, diversification, and loss. We show how the origin of a novel pigmentation trait is associated with the evolution of two regulatory sequences that control the co-expression of two key pigmentation genes. These sequences interact in unique ways with evolutionarily conserved Hox transcription factors to drive gene co-expression. Once these unique connections evolved, the alteration of this trait appears to have proceeded through changes to regulatory genes rather than regulatory sequences of the pigmentation genes. Thus, our findings support a scenario where regulatory sequence evolution provided new functions to old transcription factors, how co-expression can emerge from different utilizations of the same transcription factors, and that trait diversity was surprisingly shaped by changes in some manner to the deeply conserved regulatory genes.
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Affiliation(s)
- Eric M. Camino
- Department of Biology, University of Dayton, Dayton, Ohio, United States of America
| | - John C. Butts
- Department of Biology, University of Dayton, Dayton, Ohio, United States of America
| | - Alison Ordway
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Jordan E. Vellky
- Department of Biology, University of Dayton, Dayton, Ohio, United States of America
| | - Mark Rebeiz
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Thomas M. Williams
- Department of Biology, University of Dayton, Dayton, Ohio, United States of America
- Center for Tissue Regeneration and Engineering at Dayton, University of Dayton, Dayton, Ohio, United States of America
- * E-mail:
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