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Pan Q, Darras H, Keller L. LncRNA gene ANTSR coordinates complementary sex determination in the Argentine ant. SCIENCE ADVANCES 2024; 10:eadp1532. [PMID: 38820161 PMCID: PMC11141628 DOI: 10.1126/sciadv.adp1532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2024] [Accepted: 04/30/2024] [Indexed: 06/02/2024]
Abstract
Animals have evolved various sex determination systems. Here, we describe a newly found mechanism. A long noncoding RNA (lncRNA) transduces complementary sex determination (CSD) signal in the invasive Argentine ant. In this haplodiploid species, we identified a 5-kilobase hyper-polymorphic region underlying CSD: Heterozygous embryos become females, while homozygous and hemizygous embryos become males. Heterozygosity at the CSD locus correlates with higher expression of ANTSR, a gene that overlaps with the CSD locus and specifies an lncRNA transcript. ANTSR knockdown in CSD heterozygotes leads to male development. Comparative analyses indicated that, in Hymenoptera, ANTSR is an ancient yet rapidly evolving gene. This study reveals an lncRNA involved in genetic sex determination, alongside a previously unknown regulatory mechanism underlying sex determination based on complementarity among noncoding alleles.
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Affiliation(s)
- Qiaowei Pan
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - Hugo Darras
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University, Mainz, Germany
| | - Laurent Keller
- Social Evolution Unit, Cornuit 8, BP 855, Chesières, Switzerland
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Fujiwara K, Miyazaki S, Maekawa K. Candidate target genes of the male-specific expressed Doublesex in the termite Reticulitermes speratus. PLoS One 2024; 19:e0299900. [PMID: 38427681 PMCID: PMC10906832 DOI: 10.1371/journal.pone.0299900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 02/17/2024] [Indexed: 03/03/2024] Open
Abstract
Eusocial insects such as termites, ants, bees, and wasps exhibit a reproductive division of labor. The developmental regulation of reproductive organ (ovaries and testes) is crucial for distinguishing between reproductive and sterile castes. The development of reproductive organ in insects is regulated by sex-determination pathways. The sex determination gene Doublesex (Dsx), encoding transcription factors, plays an important role in this pathway. Therefore, clarifying the function of Dsx in the developmental regulation of sexual traits is important to understand the social evolution of eusocial insects. However, no studies have reported the function of Dsx in hemimetabolous eusocial group termites. In this study, we searched for binding sites and candidate target genes of Dsx in species with available genome information as the first step in clarifying the function of Dsx in termites. First, we focused on the Reticulitermes speratus genome and identified 101 candidate target genes of Dsx. Using a similar method, we obtained 112, 39, and 76 candidate Dsx target genes in Reticulitermes lucifugus, Coptotermes formosanus, and Macrotermes natalensis, respectively. Second, we compared the candidate Dsx target genes between species and identified 37 common genes between R. speratus and R. lucifugus. These included several genes probably involved in spermatogenesis and longevity. However, only a few common target genes were identified between R. speratus and the other two species. Finally, Dsx dsRNA injection resulted in the differential expression of several target genes, including piwi-like protein and B-box type zinc finger protein ncl-1 in R. speratus. These results provide valuable resource data for future functional analyses of Dsx in termites.
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Affiliation(s)
- Kokuto Fujiwara
- Graduate School of Science and Engineering, University of Toyama, Gofuku, Toyama, Japan
| | - Satoshi Miyazaki
- Graduate School of Agriculture, Tamagawa University, Machida, Tokyo, Japan
| | - Kiyoto Maekawa
- Academic Assembly, University of Toyama, Gofuku, Toyama, Japan
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Pospíšilová K, Van't Hof AE, Yoshido A, Kružíková R, Visser S, Zrzavá M, Bobryshava K, Dalíková M, Marec F. Masculinizer gene controls male sex determination in the codling moth, Cydia pomonella. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2023; 160:103991. [PMID: 37536576 DOI: 10.1016/j.ibmb.2023.103991] [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: 05/24/2023] [Revised: 07/13/2023] [Accepted: 07/29/2023] [Indexed: 08/05/2023]
Abstract
The molecular mechanisms of sex determination in moths and butterflies (Lepidoptera) with female heterogamety (WZ/ZZ) are poorly understood, except in the silkworm Bombyx mori. However, the Masculinizer (Masc) gene that controls male development and dosage compensation in B. mori, appears to be conserved in Lepidoptera, as its masculinizing function was recently confirmed in several moth species. In this work, we investigated the role of the Masc gene in sex determination of the codling moth Cydia pomonella (Tortricidae), a globally important pest of pome fruits and walnuts. The gene structure of the C. pomonella Masc ortholog, CpMasc, is similar to B. mori Masc. However, unlike B. mori, we identified 14 splice variants of CpMasc in the available transcriptomes. Subsequent screening for sex specificity and genetic variation using publicly available data and RT-PCR revealed three male-specific splice variants. Then qPCR analysis of these variants revealed sex-biased expression showing a peak only in early male embryos. Knockdown of CpMasc by RNAi during early embryogenesis resulted in a shift from male-to female-specific splicing of the C. pomonella doublesex (Cpdsx) gene, its downstream effector, in ZZ embryos, leading to a strongly female-biased sex ratio. These data clearly demonstrate that CpMasc functions as a masculinizing gene in the sex-determining cascade of C. pomonella. Our study also showed that CpMasc transcripts are provided maternally, as they were detected in unfertilized eggs after oviposition and in mature eggs dissected from virgin females. This finding is unique, as maternal provision of mRNA has rarely been studied in Lepidoptera.
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Affiliation(s)
- Kristýna Pospíšilová
- Biology Centre of the Czech Academy of Sciences, Institute of Entomology, 370 05, České Budějovice, Czech Republic; Faculty of Science, University of South Bohemia, 370 05, České Budějovice, Czech Republic.
| | - Arjen E Van't Hof
- Biology Centre of the Czech Academy of Sciences, Institute of Entomology, 370 05, České Budějovice, Czech Republic.
| | - Atsuo Yoshido
- Biology Centre of the Czech Academy of Sciences, Institute of Entomology, 370 05, České Budějovice, Czech Republic.
| | - Renata Kružíková
- Biology Centre of the Czech Academy of Sciences, Institute of Entomology, 370 05, České Budějovice, Czech Republic; Faculty of Science, University of South Bohemia, 370 05, České Budějovice, Czech Republic.
| | - Sander Visser
- Biology Centre of the Czech Academy of Sciences, Institute of Entomology, 370 05, České Budějovice, Czech Republic; School of Science and Engineering, University of Groningen, 9700 CC, Groningen, the Netherlands.
| | - Magda Zrzavá
- Biology Centre of the Czech Academy of Sciences, Institute of Entomology, 370 05, České Budějovice, Czech Republic; Faculty of Science, University of South Bohemia, 370 05, České Budějovice, Czech Republic.
| | - Kseniya Bobryshava
- Faculty of Science, University of South Bohemia, 370 05, České Budějovice, Czech Republic.
| | - Martina Dalíková
- Faculty of Science, University of South Bohemia, 370 05, České Budějovice, Czech Republic; Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS, 66045, USA.
| | - František Marec
- Biology Centre of the Czech Academy of Sciences, Institute of Entomology, 370 05, České Budějovice, Czech Republic.
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Chen B, Kou Z, Jiang Y, Luo X, Li P, Sun K, Wang W, Huang Y, Wang Y. Intersex is required for female sexual development in Hermetia illucens. INSECT SCIENCE 2023; 30:901-911. [PMID: 36719198 DOI: 10.1111/1744-7917.13179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 01/03/2023] [Accepted: 01/16/2023] [Indexed: 06/18/2023]
Abstract
Sex-determination pathways are extremely diverse. Understanding the mechanism of sex determination in insects is important for genetic manipulation of the pest population and for breeding of economically valuable insects. Although sex determination has been well characterized in the model species Drosophila melanogaster, little is known about this pathway in Stratiomyidae. In the present study, we first identified the Drosophila intersex (ix) homolog in Hermetia illucens, also known as the black soldier fly, which belongs to the Stratiomyidae family and which is an important insect for the conversion of various organic wastes. Phylogenetic analyses and multiple sequence alignment revealed that Hiix is conserved compared with Drosophila. We showed that Hiix is highly expressed in internal genitalia. Disruption of the Hiix gene using CRISPR/Cas9 resulted in female-specific defects in external genitalia and abnormal and undersized ovaries. Taken together, our study furthers our understanding of sex determination in insects and could facilitate breeding of H. illucens.
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Affiliation(s)
- Bihui Chen
- CAS Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, China
- CAS Center for Excellence in Biotic Interactions, University of the Chinese Academy of Sciences, Beijing, China
- Anhui Province Key Laboratory of Crop Integrated Pest Management, College of Plant Protection, Anhui Agricultural University, Hefei, China
| | - Zongqing Kou
- CAS Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, China
- CAS Center for Excellence in Biotic Interactions, University of the Chinese Academy of Sciences, Beijing, China
| | - Yuguo Jiang
- CAS Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, China
- CAS Center for Excellence in Biotic Interactions, University of the Chinese Academy of Sciences, Beijing, China
| | - Xingyu Luo
- CAS Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, China
- CAS Center for Excellence in Biotic Interactions, University of the Chinese Academy of Sciences, Beijing, China
| | - Peili Li
- Beijing Dabeinong Technology Group Co., ltd., No. 19, Chengwan Street, Suyier Village, Sujiatuo Town, Haidian District, Beijing, China
| | - Kaiji Sun
- Beijing Dabeinong Technology Group Co., ltd., No. 19, Chengwan Street, Suyier Village, Sujiatuo Town, Haidian District, Beijing, China
| | - Weiwei Wang
- Beijing Dabeinong Technology Group Co., ltd., No. 19, Chengwan Street, Suyier Village, Sujiatuo Town, Haidian District, Beijing, China
| | - Yongping Huang
- CAS Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, China
- CAS Center for Excellence in Biotic Interactions, University of the Chinese Academy of Sciences, Beijing, China
| | - Yaohui Wang
- Anhui Province Key Laboratory of Crop Integrated Pest Management, College of Plant Protection, Anhui Agricultural University, Hefei, China
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Jia Z, Hasi S, Zhan D, Hou B, Vogl C, Burger PA. Genome and Transcriptome Analyses Facilitate Genetic Control of Wohlfahrtia magnifica, a Myiasis-Causing Flesh Fly. INSECTS 2023; 14:620. [PMID: 37504626 PMCID: PMC10380434 DOI: 10.3390/insects14070620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 06/29/2023] [Accepted: 07/04/2023] [Indexed: 07/29/2023]
Abstract
Myiasis caused by Wohlfahrtia magnifica is a widespread parasitic infestation in mammals. The infested host suffers from damage as the developing larvae feed on its tissues. For the control of myiasis infestation, genetic methods have been shown to be effective and promising as an alternative to insecticides. Combining genome, isoform sequencing (Iso-Seq), and RNA sequencing (RNA-seq) data, we isolated and characterized two sex-determination genes, W. magnifica transformer (Wmtra) and W. magnifica transformer2 (Wmtra2), whose orthologs in a number of insect pests have been utilized to develop genetic control approaches. Wmtra transcripts are sex-specifically spliced; only the female transcript encodes a full-length functional protein, while the male transcript encodes a truncated and non-functional polypeptide due to the presence of the male-specific exon containing multiple in-frame stop codons. The existence of five predicted TRA/TRA2 binding sites in the male-specific exon and the surrounding intron of Wmtra, as well as the presence of an RNA-recognition motif in WmTRA2 may suggest the auto-regulation of Wmtra by its own protein interacting with WmTRA2. This results in the skipping of the male-specific exon and translation of the full-length functional protein only in females. Our comparative study in dipteran species showed that both the WmTRA and WmTRA2 proteins exhibit a high degree of similarity to their orthologs in the myiasis-causing blow flies. Additionally, transcriptome profiling performed between adult females and adult males reported 657 upregulated and 365 downregulated genes. Functional analysis showed that among upregulated genes those related to meiosis and mitosis Gene Ontology (GO) terms were enriched, while, among downregulated genes, those related to muscle cell development and aerobic metabolic processes were enriched. Among the female-biased gene set, we detected five candidate genes, vasa (vas), nanos (nanos), bicoid (bcd), Bicaudal C (BicC), and innexin5 (inx5). The promoters of these genes may be able to upregulate Cas9 expression in the germline in Cas9-based homing gene drive systems as established in some flies and mosquitoes. The isolation and characterization of these genes is an important step toward the development of genetic control programs against W. magnifica infestation.
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Affiliation(s)
- Zhipeng Jia
- Research Institute of Wildlife Ecology, Department of Interdisciplinary Life Sciences, University of Veterinary Medicine Vienna, Savoyenstrasse 1, 1160 Vienna, Austria
| | - Surong Hasi
- Key Laboratory of Clinical Diagnosis and Treatment Technology in Animal Disease, Ministry of Agriculture and Rural Affairs, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Deng Zhan
- Key Laboratory of Clinical Diagnosis and Treatment Technology in Animal Disease, Ministry of Agriculture and Rural Affairs, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Bin Hou
- Key Laboratory of Clinical Diagnosis and Treatment Technology in Animal Disease, Ministry of Agriculture and Rural Affairs, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Claus Vogl
- Institute of Animal Breeding and Genetics, Department of Biomedical Sciences, University of Veterinary Medicine Vienna, Veterinaerplatz 1, 1210 Vienna, Austria
| | - Pamela A Burger
- Research Institute of Wildlife Ecology, Department of Interdisciplinary Life Sciences, University of Veterinary Medicine Vienna, Savoyenstrasse 1, 1160 Vienna, Austria
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Fukui T, Shoji K, Kiuchi T, Suzuki Y, Katsuma S. Masculinizer is not post-transcriptionally regulated by female-specific piRNAs during sex determination in the Asian corn borer, Ostrinia furnacalis. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2023; 156:103946. [PMID: 37075905 DOI: 10.1016/j.ibmb.2023.103946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 03/31/2023] [Accepted: 04/16/2023] [Indexed: 05/03/2023]
Abstract
Lepidopteran insects are heterogametic in females, although most insect species are heterogametic in males. In a lepidopteran model species, the silkworm Bombyx mori (Bombycoidea), the uppermost sex determinant Feminizer (Fem) has been identified on the female-specific W chromosome. Fem is a precursor of PIWI-interacting small RNA (piRNA). Fem piRNA forms a complex with Siwi, one of the two B. mori PIWI-clade Argonaute proteins. In female embryos, Fem piRNA-Siwi complex cleaves the mRNA of the male-determining gene Masculinizer (Masc), directing the female-determining pathway. In male embryos, Masc activates the male-determining pathway in the absence of Fem piRNA. Recently, W chromosome-derived piRNAs complementary to Masc mRNA have also been identified in the diamondback moth Plutella xylostella (Yponomeutoidea), indicating the convergent evolution of piRNA-dependent sex determination in Lepidoptera. Here, we show that this is not the case in the Asian corn borer, Ostrinia furnacalis (Pyraloidea). Although our previous studies demonstrated that O. furnacalis Masc (OfMasc) has a masculinizing function in the embryonic stage, the expression level of OfMasc was indistinguishable between the sexes at the timing of sex determination. Deep sequencing analysis identified no female-specific small RNAs mapped onto OfMasc mRNA. Embryonic knockdown of two PIWI genes did not affect the expression level of OfMasc in either sex. These results demonstrated that piRNA-dependent reduction of Masc mRNA in female embryos is not a common strategy of sex determination, which suggests the possibility of divergent evolution of sex determinants across the order Lepidoptera.
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Affiliation(s)
- Takahiro Fukui
- Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Keisuke Shoji
- Institute for Quantitative Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-0032, Japan
| | - Takashi Kiuchi
- Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Yutaka Suzuki
- Department of Computational Biology, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8581, Japan
| | - Susumu Katsuma
- Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
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Cai Q, Wang Z, Yang F, Zhang B, Wang E, Lv J, Xu X. Expression and functional analysis of transformer-2 in Phytoseiulus persimilis and other genes potentially participating in reproductive regulation. EXPERIMENTAL & APPLIED ACAROLOGY 2023; 89:345-362. [PMID: 37027055 DOI: 10.1007/s10493-023-00786-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 03/14/2023] [Indexed: 05/09/2023]
Abstract
Transformer-2 (tra-2) is an important sex-determining gene in insects. It also plays a role in the reproduction of phytoseiid mites. We performed bioinformatic analyses for the tra-2 ortholog in Phytoseiulus persimilis (termed Pptra-2), measured its expression at different stages and quantitatively identified its function in reproduction. This gene encodes 288 amino acids with a conserved RRM domain. The peak of its expression was observed in adult females, especially ca. 5 days after mating. In addition, expression is also higher in eggs than in other stages and adult males. When Pptra-2 was silenced through RNA interference with oral delivery of dsRNA, 56% of the females had their egg hatching rates decreased in the first 5 days, from ca. 100% to ca. 20%, and maintained at low levels during the rest of the oviposition period. To detect other genes functionally related to Pptra-2, transcriptome analyses were performed on day 5 after mating. We compared mRNA expressions among interfered females with significantly reduced egg hatching rate, interfered females without significant hatching rate and CK. In total 403 differential genes were identified, of which 42 functional genes involved in the regulation of female reproduction and embryonic development were screened and discussed.
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Affiliation(s)
- Qi Cai
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Beijing, China
- Lab of Predatory Mites, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Zhenghui Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Beijing, China
- Lab of Predatory Mites, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Fan Yang
- Beijing Hooseen Biotechnology Co., Ltd, Beijing, China
| | - Bo Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Beijing, China
- Lab of Predatory Mites, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Endong Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Beijing, China
- Lab of Predatory Mites, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jiale Lv
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Beijing, China.
- Lab of Predatory Mites, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.
| | - Xuenong Xu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Beijing, China.
- Lab of Predatory Mites, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.
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Laslo M, Just J, Angelini DR. Theme and variation in the evolution of insect sex determination. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART B, MOLECULAR AND DEVELOPMENTAL EVOLUTION 2023; 340:162-181. [PMID: 35239250 PMCID: PMC10078687 DOI: 10.1002/jez.b.23125] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Revised: 11/24/2021] [Accepted: 01/03/2022] [Indexed: 11/07/2022]
Abstract
The development of dimorphic adult sexes is a critical process for most animals, one that is subject to intense selection. Work in vertebrate and insect model species has revealed that sex determination mechanisms vary widely among animal groups. However, this variation is not uniform, with a limited number of conserved factors. Therefore, sex determination offers an excellent context to consider themes and variations in gene network evolution. Here we review the literature describing sex determination in diverse insects. We have screened public genomic sequence databases for orthologs and duplicates of 25 genes involved in insect sex determination, identifying patterns of presence and absence. These genes and a 3.5 reference set of 43 others were used to infer phylogenies and compared to accepted organismal relationships to examine patterns of congruence and divergence. The function of candidate genes for roles in sex determination (virilizer, female-lethal-2-d, transformer-2) and sex chromosome dosage compensation (male specific lethal-1, msl-2, msl-3) were tested using RNA interference in the milkweed bug, Oncopeltus fasciatus. None of these candidate genes exhibited conserved roles in these processes. Amidst this variation we wish to highlight the following themes for the evolution of sex determination: (1) Unique features within taxa influence network evolution. (2) Their position in the network influences a component's evolution. Our analyses also suggest an inverse association of protein sequence conservation with functional conservation.
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Affiliation(s)
- Mara Laslo
- Department of Cell Biology, Curriculum Fellows ProgramHarvard Medical School25 Shattuck StBostonMassachusettsUSA
| | - Josefine Just
- Department of Organismic and Evolutionary BiologyHarvard University26 Oxford StCambridgeMassachusettsUSA
- Department of BiologyColby College5734 Mayflower Hill DrWatervilleMaineUSA
| | - David R. Angelini
- Department of BiologyColby College5734 Mayflower Hill DrWatervilleMaineUSA
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Zhu R, Guo J, Li G, Liu R, Yi T, Jin D. Identification of potential sex determination genes and functional analyses in Neoseiulus californicus under prey stress. PEST MANAGEMENT SCIENCE 2022; 78:5024-5040. [PMID: 36056789 DOI: 10.1002/ps.7128] [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: 12/15/2021] [Revised: 07/27/2022] [Accepted: 08/15/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND Phytoseiid mites are important natural enemies of spider mites. Sex-determination mechanism are important basic scientific issues in the reproduction and evolution of predatory mites. Clarifying sex-determination mechanism may provide reference for exploring genetic approach to have the phytoseiid mites produce more female offspring, which could improve their effectiveness as a biological control agent. RESULTS We used transcriptome sequencing to identify and characterize 20 putative sex-determination genes in the phytoseiid mite Neoseiulus californicus, a species with uncommon pseudo-arrhenotoky, including doublesex-like (dsx1-like), transformer-2 (tra-2), intersex (ix), and fruitless-like (BTB2). A significant negative correlation was found between prey stress and offspring sex ratio. But the most genes identified showed no difference in expression between the groups with lowest and highest female offspring ratios. The hatching rate and sex ratio of female offspring were reduced when the ix gene was silenced, and the oviposition days and fecundity were reduced when the BTB2 gene was silenced. The fecundity was reduced when the tra2 gene was silenced and the snf gene is essential for oviposition in female. There was no effect on reproduction and female sex determination when silencing the dsx1-like and dsx2-like gene. CONCLUSION The genes BTB2, tra2 and snf are involved in oviposition, and ix may be involved in female sex determination and egg formation in Neoseiulus californicus. The results are conductive to further understanding molecular regulatory mechanism of sex determination in predatory mites and may provide a reference for better use of this predatory by producing more females. © 2022 Society of Chemical Industry.
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Affiliation(s)
- Rui Zhu
- Institute of Entomology, Guizhou University, Guizhou Provincial Key Laboratory for Agricultural Pest Management of the Mountainous Region, the Scientific Observing and Experimental Station of Crop Pest in Guiyang, Ministry of Agriculture and Rural Affirs, the People's Republic of China, Guiyang, China
| | - Jianjun Guo
- Institute of Entomology, Guizhou University, Guizhou Provincial Key Laboratory for Agricultural Pest Management of the Mountainous Region, the Scientific Observing and Experimental Station of Crop Pest in Guiyang, Ministry of Agriculture and Rural Affirs, the People's Republic of China, Guiyang, China
| | - Gang Li
- Institute of Entomology, Guizhou University, Guizhou Provincial Key Laboratory for Agricultural Pest Management of the Mountainous Region, the Scientific Observing and Experimental Station of Crop Pest in Guiyang, Ministry of Agriculture and Rural Affirs, the People's Republic of China, Guiyang, China
| | - Rundong Liu
- Institute of Entomology, Guizhou University, Guizhou Provincial Key Laboratory for Agricultural Pest Management of the Mountainous Region, the Scientific Observing and Experimental Station of Crop Pest in Guiyang, Ministry of Agriculture and Rural Affirs, the People's Republic of China, Guiyang, China
| | - Tianci Yi
- Institute of Entomology, Guizhou University, Guizhou Provincial Key Laboratory for Agricultural Pest Management of the Mountainous Region, the Scientific Observing and Experimental Station of Crop Pest in Guiyang, Ministry of Agriculture and Rural Affirs, the People's Republic of China, Guiyang, China
| | - Daochao Jin
- Institute of Entomology, Guizhou University, Guizhou Provincial Key Laboratory for Agricultural Pest Management of the Mountainous Region, the Scientific Observing and Experimental Station of Crop Pest in Guiyang, Ministry of Agriculture and Rural Affirs, the People's Republic of China, Guiyang, China
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10
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Dynamics of sex-biased gene expression during development in the stick insect Timema californicum. Heredity (Edinb) 2022; 129:113-122. [PMID: 35581477 PMCID: PMC9338061 DOI: 10.1038/s41437-022-00536-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 04/04/2022] [Accepted: 04/06/2022] [Indexed: 12/03/2022] Open
Abstract
Sexually dimorphic phenotypes are thought to arise primarily from sex-biased gene expression during development. Major changes in developmental strategies, such as the shift from hemimetabolous to holometabolous development, are therefore expected to have profound consequences for the dynamics of sex-biased gene expression. However, no studies have previously examined sex-biased gene expression during development in hemimetabolous insects, precluding comparisons between developmental strategies. Here we characterized sex-biased gene expression at three developmental stages in a hemimetabolous stick insect (Timema californicum): hatchlings, juveniles, and adults. As expected, the proportion of sex-biased genes gradually increased during development, mirroring the gradual increase of phenotypic sexual dimorphism. Sex-biased genes identified at early developmental stages were generally consistently male- or female-biased at later stages, suggesting their importance in sexual differentiation. Additionally, we compared the dynamics of sex-biased gene expression during development in T. californicum to those of the holometabolous fly Drosophila melanogaster by reanalyzing publicly available RNA-seq data from third instar larval, pupal and adult stages. In D. melanogaster, 84% of genes were sex-biased at the adult stage (compared to only 20% in T. californicum), and sex-biased gene expression increased abruptly at the adult stage when morphological sexual dimorphism is manifested. Our findings are consistent with the prediction that the dynamics of sex-biased gene expression during development differ extensively between holometabolous and hemimetabolous insect species.
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Wang Y, Rensink AH, Fricke U, Riddle MC, Trent C, van de Zande L, Verhulst EC. Doublesex regulates male-specific differentiation during distinct developmental time windows in a parasitoid wasp. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2022; 142:103724. [PMID: 35093500 DOI: 10.1016/j.ibmb.2022.103724] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 01/19/2022] [Accepted: 01/19/2022] [Indexed: 06/14/2023]
Abstract
Sexually dimorphic traits in insects are subject to sexual selection, but our knowledge of the underlying molecular mechanisms is still scarce. Here we investigate how the highly conserved gene, Doublesex (Dsx), is involved in shaping sexual dimorphism in the model parasitoid wasp Nasonia vitripennis (Hymenoptera: Pteromalidae). First, we present the revised Dsx gene structure including an alternative transcription start, and two additional male NvDsx transcript isoforms. We show sex-specific NvDsx expression and splicing throughout development, and demonstrate that transient NvDsx silencing in different male developmental stages shifts two sexually dimorphic traits from male to female morphology, with the effect being dependent on the timing of silencing. In addition, we determined the effect of NvDsx on the development of reproductive organs. Transient silencing of NvDsx in early male larvae affects the growth and differentiation of the internal and external reproductive tissues. We did not observe phenotypic changes in females after NvDsx silencing. Our results indicate that male NvDsx is required to suppress female-specific traits and/or to promote male-specific traits during distinct developmental windows. This provides new insights into the regulatory activity of Dsx during male wasp development in the Hymenoptera.
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Affiliation(s)
- Yidong Wang
- Wageningen University, Laboratory of Entomology, Wageningen, the Netherlands
| | - Anna H Rensink
- Evolutionary Genetics, Development and Behaviour, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, the Netherlands
| | - Ute Fricke
- Wageningen University, Laboratory of Entomology, Wageningen, the Netherlands
| | - Megan C Riddle
- Biology Department, Western Washington University, Washington, USA
| | - Carol Trent
- Biology Department, Western Washington University, Washington, USA
| | - Louis van de Zande
- Evolutionary Genetics, Development and Behaviour, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, the Netherlands
| | - Eveline C Verhulst
- Wageningen University, Laboratory of Entomology, Wageningen, the Netherlands; Wageningen University, Laboratory of Genetics, Wageningen, the Netherlands.
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12
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Zarkower D, Murphy MW. DMRT1: An Ancient Sexual Regulator Required for Human Gonadogenesis. Sex Dev 2022; 16:112-125. [PMID: 34515237 PMCID: PMC8885888 DOI: 10.1159/000518272] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 05/25/2021] [Indexed: 01/03/2023] Open
Abstract
Transcriptional regulators related to the invertebrate sexual regulators doublesex and mab-3 occur throughout metazoans and control sex in most animal groups. Seven of these DMRT genes are found in mammals, and mouse genetics has shown that one, Dmrt1, plays a crucial role in testis differentiation, both in germ cells and somatic cells. Deletions and, more recently, point mutations affecting human DMRT1 have demonstrated that its heterozygosity is associated with 46,XY complete gonadal dysgenesis. Most of our detailed knowledge of DMRT1 function in the testis, the focus of this review, derives from mouse studies, which have revealed that DMRT1 is essential for male somatic and germ cell differentiation and maintenance of male somatic cell fate after differentiation. Moreover, ectopic DMRT1 can reprogram differentiated female granulosa cells into male Sertoli-like cells. The ability of DMRT1 to control sexual cell fate likely derives from at least 3 properties. First, DMRT1 functionally collaborates with another key male sex regulator, SOX9, and possibly other proteins to maintain and reprogram sexual cell fate. Second, and related, DMRT1 appears to function as a pioneer transcription factor, binding "closed" inaccessible chromatin and promoting its opening to allow binding by other regulators including SOX9. Third, DMRT1 binds DNA by a highly unusual form of interaction and can bind with different stoichiometries.
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Affiliation(s)
- David Zarkower
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN, USA
| | - Mark W. Murphy
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN, USA
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13
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Jin B, Zhao Y, Dong Y, Liu P, Sun Y, Li X, Zhang X, Chen XG, Gu J. Alternative splicing patterns of doublesex reveal a missing link between Nix and doublesex in the sex determination cascade of Aedes albopictus. INSECT SCIENCE 2021; 28:1601-1620. [PMID: 33179439 DOI: 10.1111/1744-7917.12886] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 10/26/2020] [Accepted: 10/28/2020] [Indexed: 05/06/2023]
Abstract
Sexual development in insects is regulated by a complicated hierarchical cascade of sex determination. The primary signals are diverse, whereas the central nexus doublesex (dsx) gene is relatively conserved within the pathway. Aedes (Stegomyia) albopictus is an important vector with an extensive worldwide distribution. We previously reported that Ae. albopictus dsx (Aalbdsx) yields one male- (AalbdsxM ) and three female-specific isoforms (AalbdsxF1-3 ); however, the spatiotemporal expression profiles and mechanisms regulating sex-specific alternative splicing require further investigation. In this study, we demonstrated that the AalbdsxM messenger RNA (mRNA) represents the default pattern when analyzed in human foreskin fibroblasts and HeLa cells. We combined reverse transcription polymerase chain reaction with RNA immunoprecipitation using specific antibodies against tagged Ae. albopictus male-determining factor AalNix and confirmed that AalNix indirectly regulates dsx pre-mRNA and regulates its alternative splicing. During the early embryo stage (0-2 and 4-8 h), maternal dsxF and default splicing dsxM were detected in both sexes; the expression of dsxM then decreased until sufficient AalNix transcripts accumulated in male embryos at 20-24 h. These findings suggest that one or more potential dsx splicing enhancers can shift dsxM to dsxF in both sexes; however, the presence of Nix influences the function of this unknown splicing enhancer and ultimately leads to the formation of dsxM in males. Finally, our results provide important insight into the regulatory mechanism of dsx alternative splicing in the mosquito.
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Affiliation(s)
- Binbin Jin
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, China
| | - Yijie Zhao
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, China
| | - Yunqiao Dong
- Reproductive Medical Centre of Guangdong Women and Children Hospital, Guangzhou, 511442, China
| | - Peiwen Liu
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, China
| | - Yan Sun
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, China
| | - Xiaocong Li
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, China
| | - Xin Zhang
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, China
| | - Xiao-Guang Chen
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, China
| | - Jinbao Gu
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, China
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14
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Visser S, Voleníková A, Nguyen P, Verhulst EC, Marec F. A conserved role of the duplicated Masculinizer gene in sex determination of the Mediterranean flour moth, Ephestia kuehniella. PLoS Genet 2021; 17:e1009420. [PMID: 34339412 PMCID: PMC8360546 DOI: 10.1371/journal.pgen.1009420] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 08/12/2021] [Accepted: 06/22/2021] [Indexed: 12/28/2022] Open
Abstract
Sex determination in the silkworm, Bombyx mori, is based on Feminizer (Fem), a W-linked Fem piRNA that triggers female development in WZ individuals, and the Z-linked Masculinizer (Masc), which initiates male development and dosage compensation in ZZ individuals. While Fem piRNA is missing in a close relative of B. mori, Masc determines sex in several representatives of distant lepidopteran lineages. We studied the molecular mechanisms of sex determination in the Mediterranean flour moth, Ephestia kuehniella (Pyralidae). We identified an E. kuehniella Masc ortholog, EkMasc, and its paralog resulting from a recent duplication, EkMascB. Both genes are located on the Z chromosome and encode a similar Masc protein that contains two conserved domains but has lost the conserved double zinc finger domain. We developed PCR-based genetic sexing and demonstrated a peak in the expression of EkMasc and EkMascB genes only in early male embryos. Simultaneous knock-down experiments of both EkMasc and EkMascB using RNAi during early embryogenesis led to a shift from male- to female-specific splicing of the E. kuehniella doublesex gene (Ekdsx), their downstream effector, in ZZ embryos and resulted in a strong female-biased sex-ratio. Our results thus confirmed the conserved role of EkMasc and/or EkMascB in masculinization. We suggest that the C-terminal proline-rich domain, we have identified in all functionally confirmed Masc proteins, in conjunction with the masculinizing domain, is important for transcriptional regulation of sex determination in Lepidoptera. The function of the Masc double zinc finger domain is still unknown, but appears to have been lost in E. kuehniella. The sex-determining cascade in the silkworm, Bombyx mori, differs greatly from those of other insects. In B. mori, female development is initiated by Fem piRNA expressed from the W chromosome during early embryogenesis. Fem piRNA silences Masculinizer (Masc) thereby blocking the male pathway resulting in female development. It is currently unknown whether this cascade is conserved across Lepidoptera. In the Mediterranean flour moth, Ephestia kuehniella, we identified an ortholog of Masc and discovered its functional duplication on the Z chromosome, which has not yet been found in any other lepidopteran species. We provide two lines of evidence that the EkMasc and/or EkMascB genes play an essential role in masculinization: (i) they show a peak of expression during early embryogenesis in ZZ but not in WZ embryos and (ii) their simultaneous silencing by RNAi results in female-specific splicing of the E. kuehniella doublesex gene (Ekdsx) in ZZ embryos and in a female-biased sex ratio. Our results suggest a conserved role of the duplicated Masc gene in sex determination of E. kuehniella.
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Affiliation(s)
- Sander Visser
- Biology Centre of the Czech Academy of Sciences, Institute of Entomology, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Anna Voleníková
- Biology Centre of the Czech Academy of Sciences, Institute of Entomology, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Petr Nguyen
- Biology Centre of the Czech Academy of Sciences, Institute of Entomology, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Eveline C. Verhulst
- Laboratory of Entomology, Wageningen University & Research, Wageningen, The Netherlands
| | - František Marec
- Biology Centre of the Czech Academy of Sciences, Institute of Entomology, České Budějovice, Czech Republic
- * E-mail:
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15
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Evolution of sexual development and sexual dimorphism in insects. Curr Opin Genet Dev 2021; 69:129-139. [PMID: 33848958 DOI: 10.1016/j.gde.2021.02.011] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 02/19/2021] [Accepted: 02/24/2021] [Indexed: 12/18/2022]
Abstract
Most animal species consist of two distinct sexes. At the morphological, physiological, and behavioral levels the differences between males and females are numerous and dramatic, yet at the genomic level they are often slight or absent. This disconnect is overcome because simple genetic differences or environmental signals are able to direct the sex-specific expression of a shared genome. A canonical picture of how this process works in insects emerged from decades of work on Drosophila. But recent years have seen an explosion of molecular-genetic and developmental work on a broad range of insects. Drawing these studies together, we describe the evolution of sexual dimorphism from a comparative perspective and argue that insect sex determination and differentiation systems are composites of rapidly evolving and highly conserved elements.
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16
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Jin B, Zhao Y, Liu P, Sun Y, Li X, Zhang X, Chen XG, Gu J. The direct regulation of Aalbdsx on AalVgR is indispensable for ovarian development in Aedes albopictus. PEST MANAGEMENT SCIENCE 2021; 77:1654-1667. [PMID: 33205515 DOI: 10.1002/ps.6185] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 11/13/2020] [Accepted: 11/17/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Aedes albopictus is an important vector with an extensive worldwide distribution. Only female mosquitoes play a significant role in the transmission of pathogens. Doublesex (dsx) is a central nexus gene in the insect somatic sex determination hierarchy. RESULTS In this study, we characterized the full-length sex-specific splicing forms of the Ae. albopictus dsx (Aalbdsx) gene. Then, we identified 15 direct target genes of DSX in adult females using digital gene expression combined with quantitative real-time polymerase chain reaction (qPCR) by performing a chromatin immunoprecipitation (ChIP) assay with specific DSX antibodies. Knockdown of Aalbdsx suppressed ovarian development and decreased the transcript levels of the Aalbdsx target vitellogenin receptor (VgR) gene, whereas vitellogenin (Vg) expression showed an increase in the fat body. Genes in the major Vg regulatory pathway were also up-regulated. CONCLUSION Our results suggest that both Vg and VgR are direct target genes of Aalbdsx and that direct regulation of Aalbdsx on VgR is indispensable for ovarian development in Ae. albopictus, which not only provides a reference for the further elucidation of the evolutionarily conserved role of dsx in Ae. albopictus sexual differentiation but also reveals potential molecular targets for application to the development of sterile male mosquitoes to be released for vector control. © 2020 Society of Chemical Industry.
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Affiliation(s)
- Binbin Jin
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Yijie Zhao
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Peiwen Liu
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Yan Sun
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Xiaocong Li
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Xin Zhang
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Xiao-Guang Chen
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Jinbao Gu
- Department of Pathogen Biology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
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17
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Yang X, Chen K, Wang Y, Yang D, Huang Y. The Sex Determination Cascade in the Silkworm. Genes (Basel) 2021; 12:genes12020315. [PMID: 33672402 PMCID: PMC7926724 DOI: 10.3390/genes12020315] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 02/05/2021] [Accepted: 02/09/2021] [Indexed: 12/22/2022] Open
Abstract
In insects, sex determination pathways involve three levels of master regulators: primary signals, which determine the sex; executors, which control sex-specific differentiation of tissues and organs; and transducers, which link the primary signals to the executors. The primary signals differ widely among insect species. In Diptera alone, several unrelated primary sex determiners have been identified. However, the doublesex (dsx) gene is highly conserved as the executor component across multiple insect orders. The transducer level shows an intermediate level of conservation. In many, but not all examined insects, a key transducer role is performed by transformer (tra), which controls sex-specific splicing of dsx. In Lepidoptera, studies of sex determination have focused on the lepidopteran model species Bombyx mori (the silkworm). In B. mori, the primary signal of sex determination cascade starts from Fem, a female-specific PIWI-interacting RNA, and its targeting gene Masc, which is apparently specific to and conserved among Lepidoptera. Tra has not been found in Lepidoptera. Instead, the B. mori PSI protein binds directly to dsx pre-mRNA and regulates its alternative splicing to produce male- and female-specific transcripts. Despite this basic understanding of the molecular mechanisms underlying sex determination, the links among the primary signals, transducers and executors remain largely unknown in Lepidoptera. In this review, we focus on the latest findings regarding the functions and working mechanisms of genes involved in feminization and masculinization in Lepidoptera and discuss directions for future research of sex determination in the silkworm.
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Affiliation(s)
- Xu Yang
- Key Laboratory of Insect Developmental and Evolutionary Biology, Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China; (X.Y.); (K.C.); (Y.W.); (D.Y.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kai Chen
- Key Laboratory of Insect Developmental and Evolutionary Biology, Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China; (X.Y.); (K.C.); (Y.W.); (D.Y.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yaohui Wang
- Key Laboratory of Insect Developmental and Evolutionary Biology, Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China; (X.Y.); (K.C.); (Y.W.); (D.Y.)
| | - Dehong Yang
- Key Laboratory of Insect Developmental and Evolutionary Biology, Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China; (X.Y.); (K.C.); (Y.W.); (D.Y.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yongping Huang
- Key Laboratory of Insect Developmental and Evolutionary Biology, Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China; (X.Y.); (K.C.); (Y.W.); (D.Y.)
- Correspondence:
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18
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femaleless Controls Sex Determination and Dosage Compensation Pathways in Females of Anopheles Mosquitoes. Curr Biol 2021; 31:1084-1091.e4. [PMID: 33417880 PMCID: PMC7955153 DOI: 10.1016/j.cub.2020.12.014] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 11/09/2020] [Accepted: 12/11/2020] [Indexed: 01/04/2023]
Abstract
The insect sex determination and the intimately linked dosage compensation pathways represent a challenging evolutionary puzzle that has been solved only in Drosophila melanogaster. Analyses of orthologs of the Drosophila genes identified in non-drosophilid taxa1,2 revealed that evolution of sex determination pathways is consistent with a bottom-up mode,3 where only the terminal genes within the pathway are well conserved. doublesex (dsx), occupying a bottom-most position and encoding sex-specific proteins orchestrating downstream sexual differentiation processes, is an ancient sex-determining gene present in all studied species.2,4,5 With the exception of lepidopterans, its female-specific splicing is known to be regulated by transformer (tra) and its co-factor transformer-2 (tra2).6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 Here we show that in the African malaria mosquito Anopheles gambiae, a gene, which likely arose in the Anopheles lineage and which we call femaleless (fle), controls sex determination in females by regulating splicing of dsx and fruitless (fru; another terminal gene within a branch of the sex determination pathway). Moreover, fle represents a novel molecular link between the sex determination and dosage compensation pathways. It is necessary to suppress activation of dosage compensation in females, as demonstrated by the significant upregulation of the female X chromosome genes and a correlated female-specific lethality, but no negative effect on males, in response to fle knockdown. This unexpected property, combined with a high level of conservation in sequence and function in anopheline mosquitoes, makes fle an excellent target for genetic control of all major vectors of human malaria. fle is a new sex determination pathway element conserved in Anopheles mosquitoes fle may have originated in the Anopheles lineage and is highly conserved in Anopheles fle suppresses activation of dosage compensation in females Depletion of fle transcripts is lethal or otherwise deleterious to females
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19
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Yan Y, Scott MJ. Building a transgenic sexing strain for genetic control of the Australian sheep blow fly Lucilia cuprina using two lethal effectors. BMC Genet 2020; 21:141. [PMID: 33339506 PMCID: PMC8348823 DOI: 10.1186/s12863-020-00947-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Background The sterile insect technique (SIT) has been
successfully used in many pest management programs worldwide.
Some SIT programs release both sexes due to the lack of genetic
sexing strains or efficient sex separation methods but sterile
females are ineffective control agents. Transgenic sexing
strains (TSS) using the tetracycline-off control system have
been developed in a variety of insect pests, from which females
die by either of two commonly used lethal effectors:
overexpression of the transcription factor tetracycline transactivator (tTA)
or ectopic expression of a proapoptotic gene, such as head involution defective
(hid). The lethality from
tTA overexpression is thought to be due to “transcriptional
squelching”, while hid causes
lethality by induction of apoptosis. This study aims to create
and characterize a TSS of Lucilia
cuprina, which is a major pest of sheep, by
combining both lethal effectors in a single transgenic
strain. Results Here a stable TSS of L.
cuprina (DH6) that carries two lethal effectors
was successfully generated, by crossing FL3#2 which carries a
female-specific tTA overexpression cassette, with EF1#12 which
carries a tTA-regulated LshidAla2 cassette. Females with
one copy of the FL3#2 transgene are viable but up to 99.8% of
homozygous females die at the pupal stage when raised on diet
that lacks tetracycline. Additionally, the female lethality of
FL3#2 was partially repressed by supplying tetracycline to the
parental generation. With an additional LshidAla2 effector, the female
lethality of DH6 is 100% dominant and cannot be repressed by
maternal tetracycline. DH6 females die at the late-larval stage.
Several fitness parameters important for mass rearing such as
hatching rate, adult emergence and sex ratio were comparable to
those of the wild type strain. Conclusions Compared to the parental FL3#2 strain, the DH6
strain shows stronger female lethality and lethality occurs at
an earlier stage of development. The combination of two
tTA-dependent lethal effectors could improve strain stability
under mass rearing and could reduce the risk of resistance in
the field if fertile males are released. Our approach could be
easily adapted for other pest species for an efficient, safe and
sustainable genetic control program. Supplementary Information The online version contains supplementary material available
at 10.1186/s12863-020-00947-y.
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Affiliation(s)
- Ying Yan
- Department of Entomology and Plant Pathology, North Carolina State University, Campus Box 7613, Raleigh, NC, 27695-7613, USA.,Department of Insect Biotechnology in Plant Protection, Justus-Liebig-University Giessen, Institute for Insect Biotechnology, Winchesterstraße 2, 35394, Giessen, Germany
| | - Maxwell J Scott
- Department of Entomology and Plant Pathology, North Carolina State University, Campus Box 7613, Raleigh, NC, 27695-7613, USA.
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20
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Ferguson KB, Pannebakker BA, Centurión A, van den Heuvel J, Nieuwenhuis R, Becker FFM, Schijlen E, Thiel A, Zwaan BJ, Verhulst EC. Bracon brevicornis Genome Showcases the Potential of Linked-Read Sequencing in Identifying a Putative Complementary Sex Determiner Gene. Genes (Basel) 2020; 11:E1390. [PMID: 33255162 PMCID: PMC7759789 DOI: 10.3390/genes11121390] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 11/18/2020] [Indexed: 01/24/2023] Open
Abstract
Bracon brevicornis is an ectoparasitoid of a wide range of larval-stage Lepidopterans, including several pests of important crops, such as the corn borer, Ostrinia nubilalis. It is also one of the earliest documented cases of complementary sex determination in Hymenoptera. Here, we present the linked-read-based genome of B. brevicornis, complete with an ab initio-derived annotation and protein comparisons with fellow braconids, Fopius arisanus and Diachasma alloeum. We demonstrate the potential of linked-read assemblies in exploring regions of heterozygosity and search for structural and homology-derived evidence of the complementary sex determiner gene (csd).
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Affiliation(s)
- Kim B. Ferguson
- Laboratory of Genetics, Wageningen University & Research, 6708PB Wageningen, The Netherlands; (B.A.P.); (J.v.d.H.); (F.F.M.B.); (B.J.Z.)
| | - Bart A. Pannebakker
- Laboratory of Genetics, Wageningen University & Research, 6708PB Wageningen, The Netherlands; (B.A.P.); (J.v.d.H.); (F.F.M.B.); (B.J.Z.)
| | - Alejandra Centurión
- Population and Evolutionary Ecology Group, Institute of Ecology, FB02, University of Bremen, 28359 Bremen, Germany; (A.C.); (A.T.)
| | - Joost van den Heuvel
- Laboratory of Genetics, Wageningen University & Research, 6708PB Wageningen, The Netherlands; (B.A.P.); (J.v.d.H.); (F.F.M.B.); (B.J.Z.)
| | - Ronald Nieuwenhuis
- Bioscience, Wageningen University & Research, 6708PB Wageningen, The Netherlands; (R.N.); (E.S.)
| | - Frank F. M. Becker
- Laboratory of Genetics, Wageningen University & Research, 6708PB Wageningen, The Netherlands; (B.A.P.); (J.v.d.H.); (F.F.M.B.); (B.J.Z.)
| | - Elio Schijlen
- Bioscience, Wageningen University & Research, 6708PB Wageningen, The Netherlands; (R.N.); (E.S.)
| | - Andra Thiel
- Population and Evolutionary Ecology Group, Institute of Ecology, FB02, University of Bremen, 28359 Bremen, Germany; (A.C.); (A.T.)
| | - Bas J. Zwaan
- Laboratory of Genetics, Wageningen University & Research, 6708PB Wageningen, The Netherlands; (B.A.P.); (J.v.d.H.); (F.F.M.B.); (B.J.Z.)
| | - Eveline C. Verhulst
- Laboratory of Entomology, Wageningen University & Research, 6708PB Wageningen, The Netherlands;
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The transformer-2 and fruitless characterisation with developmental expression profiles of sex-determining genes in Bactrocera dorsalis and B. correcta. Sci Rep 2020; 10:17938. [PMID: 33087807 PMCID: PMC7578103 DOI: 10.1038/s41598-020-74856-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 10/07/2020] [Indexed: 12/12/2022] Open
Abstract
Sex determination in tephritid fruit flies involves a signaling cascade of alternatively spliced genes. The Transformer (TRA) and Transformer-2 (TRA-2) complex establishes an autoregulatory loop switching sex-specific splicing of tra pre-mRNA in females. The TRA/TRA-2 complex also regulates the sex-specific splicing of downstream effector genes, doublesex (dsx) and fruitless (fru). In Ceratitis capitata, a Maleness-on the-Y (MoY) gene modulates sex-specifically spliced Cctra pre-mRNA and results in the breakdown of the Cctra autoregulatory loop in males. In this study, the tra-2 and fru genes were characterised in two key pests, Bactrocera dorsalis and B. correcta. The tra-2 genes showed high degrees of conservation among tephritids. The complex gene organisation for each of Bdfru and Bcfru were identified. There are sex-specific and non sex-specific transcripts generated by alternative promoters as found in Drosophila melanogaster and other insects. RNAi knockdown of Bdtra transcripts showed that BdTRA controls the sex-specific splicing of Bddsx and Bdfru pre-mRNAs. Developmental expression analysis shows that multiple splice variants of Bdtra and Bctra RNAs are present before and during cellular blastoderm formation and that the mature sex-specific variants become fixed later in embryogenesis. Furthermore, the BddsxM splice variants are found in early embryos at the beginning of gastulation, but BdfruM does not appear until the larval stage. We proposed that the zygotic tra loop is initiated in both female and male embryos before becoming automatised or abolished by MoY, respectively.
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22
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Tvedte ES, Walden KKO, McElroy KE, Werren JH, Forbes AA, Hood GR, Logsdon JM, Feder JL, Robertson HM. Genome of the Parasitoid Wasp Diachasma alloeum, an Emerging Model for Ecological Speciation and Transitions to Asexual Reproduction. Genome Biol Evol 2020; 11:2767-2773. [PMID: 31553440 PMCID: PMC6781843 DOI: 10.1093/gbe/evz205] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/20/2019] [Indexed: 12/24/2022] Open
Abstract
Parasitoid wasps are among the most speciose animals, yet have relatively few available genomic resources. We report a draft genome assembly of the wasp Diachasma alloeum (Hymenoptera: Braconidae), a host-specific parasitoid of the apple maggot fly Rhagoletis pomonella (Diptera: Tephritidae), and a developing model for understanding how ecological speciation can “cascade” across trophic levels. Identification of gene content confirmed the overall quality of the draft genome, and we manually annotated ∼400 genes as part of this study, including those involved in oxidative phosphorylation, chemosensation, and reproduction. Through comparisons to model hymenopterans such as the European honeybee Apis mellifera and parasitoid wasp Nasonia vitripennis, as well as a more closely related braconid parasitoid Microplitis demolitor, we identified a proliferation of transposable elements in the genome, an expansion of chemosensory genes in parasitoid wasps, and the maintenance of several key genes with known roles in sexual reproduction and sex determination. The D. alloeum genome will provide a valuable resource for comparative genomics studies in Hymenoptera as well as specific investigations into the genomic changes associated with ecological speciation and transitions to asexuality.
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Affiliation(s)
- Eric S Tvedte
- Department of Biology, University of Iowa, IA.,Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD
| | | | | | | | | | - Glen R Hood
- Department of Biological Sciences, Wayne State University, Detroit, MI
| | | | - Jeffrey L Feder
- Department of Biological Sciences, University of Notre Dame, IN
| | - Hugh M Robertson
- Department of Entomology, University of Illinois at Urbana-Champaign, IL
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23
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miRNA-1-3p is an early embryonic male sex-determining factor in the Oriental fruit fly Bactrocera dorsalis. Nat Commun 2020; 11:932. [PMID: 32071305 PMCID: PMC7029022 DOI: 10.1038/s41467-020-14622-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 07/18/2019] [Indexed: 11/08/2022] Open
Abstract
Regulation of male sexual differentiation by a Y chromosome-linked male determining factor (M-factor) is one of a diverse array of sex determination mechanisms found in insects. By deep sequencing of small RNAs from Bactrocera dorsalis early embryos, we identified an autosomal-derived microRNA, miR-1-3p, that has predicted target sites in the transformer gene (Bdtra) required for female sex determination. We further demonstrate by both in vitro and in vivo tests that miR-1-3p suppresses Bdtra expression. Injection of a miR-1-3p mimic in early embryos results in 87-92% phenotypic males, whereas knockdown of miR-1-3p by an inhibitor results in 67-77% phenotypic females. Finally, CRISPR/Cas9-mediated knockout of miR-1-3p results in the expression of female-specific splice variants of Bdtra and doublesex (Bddsx), and induced sex reversal of XY individuals into phenotypic females. These results indicate that miR-1-3p is required for male sex determination in early embryogenesis in B. dorsalis as an intermediate male determiner.
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24
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Zhang YX, Chen X, Wang JP, Zhang ZQ, Wei H, Yu HY, Zheng HK, Chen Y, Zhang LS, Lin JZ, Sun L, Liu DY, Tang J, Lei Y, Li XM, Liu M. Genomic insights into mite phylogeny, fitness, development, and reproduction. BMC Genomics 2019; 20:954. [PMID: 31818245 PMCID: PMC6902594 DOI: 10.1186/s12864-019-6281-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 11/13/2019] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Predatory mites (Acari: Phytoseiidae) are the most important beneficial arthropods used in augmentative biological pest control of protected crops around the world. However, the genomes of mites are far less well understood than those of insects and the evolutionary relationships among mite and other chelicerate orders are contested, with the enigmatic origin of mites at one of the centres in discussion of the evolution of Arachnida. RESULTS We here report the 173 Mb nuclear genome (from 51.75 Gb pairs of Illumina reads) of the predatory mite, Neoseiulus cucumeris, a biocontrol agent against pests such as mites and thrips worldwide. We identified nearly 20.6 Mb (~ 11.93% of this genome) of repetitive sequences and annotated 18,735 protein-coding genes (a typical gene 2888 bp in size); the total length of protein-coding genes was about 50.55 Mb (29.2% of this assembly). About 37% (6981) of the genes are unique to N. cucumeris based on comparison with other arachnid genomes. Our phylogenomic analysis supported the monophyly of Acari, therefore rejecting the biphyletic origin of mites advocated by other studies based on limited gene fragments or few taxa in recent years. Our transcriptomic analyses of different life stages of N. cucumeris provide new insights into genes involved in its development. Putative genes involved in vitellogenesis, regulation of oviposition, sex determination, development of legs, signal perception, detoxification and stress-resistance, and innate immune systems are identified. CONCLUSIONS Our genomics and developmental transcriptomics analyses of N. cucumeris provide invaluable resources for further research on the development, reproduction, and fitness of this economically important mite in particular and Arachnida in general.
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Affiliation(s)
- Yan-Xuan Zhang
- Research Center of Engineering and Technology of Natural Enemy Resource of Crop Pest in Fujian, Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, 350003 People’s Republic of China
| | - Xia Chen
- Research Center of Engineering and Technology of Natural Enemy Resource of Crop Pest in Fujian, Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, 350003 People’s Republic of China
| | - Jie-Ping Wang
- Agricultural Bio-Resources Research Institute, Fujian Academy of Agricultural Sciences, Fuzhou, 350013 People’s Republic of China
| | - Zhi-Qiang Zhang
- Landcare Research, Auckland and School of Biological Sciences, The University of Auckland, Auckland, New Zealand
| | - Hui Wei
- Research Center of Engineering and Technology of Natural Enemy Resource of Crop Pest in Fujian, Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, 350003 People’s Republic of China
| | - Hai-Yan Yu
- Biomarker Technologies Corporation, Beijing, 101300 People’s Republic of China
| | - Hong-Kun Zheng
- Biomarker Technologies Corporation, Beijing, 101300 People’s Republic of China
| | - Yong Chen
- Research Center of Engineering and Technology of Natural Enemy Resource of Crop Pest in Fujian, Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, 350003 People’s Republic of China
| | - Li-Sheng Zhang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193 People’s Republic of China
| | - Jian-Zhen Lin
- Fujian Yanxuan Bio-preventing and Technology Biocontrol Corporation, Fuzhou, People’s Republic of China
| | - Li Sun
- Research Center of Engineering and Technology of Natural Enemy Resource of Crop Pest in Fujian, Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, 350003 People’s Republic of China
| | - Dong-Yuan Liu
- Biomarker Technologies Corporation, Beijing, 101300 People’s Republic of China
| | - Juan Tang
- Biomarker Technologies Corporation, Beijing, 101300 People’s Republic of China
| | - Yan Lei
- Biomarker Technologies Corporation, Beijing, 101300 People’s Republic of China
| | - Xu-Ming Li
- Biomarker Technologies Corporation, Beijing, 101300 People’s Republic of China
| | - Min Liu
- Biomarker Technologies Corporation, Beijing, 101300 People’s Republic of China
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25
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Wexler J, Delaney EK, Belles X, Schal C, Wada-Katsumata A, Amicucci MJ, Kopp A. Hemimetabolous insects elucidate the origin of sexual development via alternative splicing. eLife 2019; 8:e47490. [PMID: 31478483 PMCID: PMC6721801 DOI: 10.7554/elife.47490] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2019] [Accepted: 08/11/2019] [Indexed: 02/02/2023] Open
Abstract
Insects are the only known animals in which sexual differentiation is controlled by sex-specific splicing. The doublesex transcription factor produces distinct male and female isoforms, which are both essential for sex-specific development. dsx splicing depends on transformer, which is also alternatively spliced such that functional Tra is only present in females. This pathway has evolved from an ancestral mechanism where dsx was independent of tra and expressed and required only in males. To reconstruct this transition, we examined three basal, hemimetabolous insect orders: Hemiptera, Phthiraptera, and Blattodea. We show that tra and dsx have distinct functions in these insects, reflecting different stages in the changeover from a transcription-based to a splicing-based mode of sexual differentiation. We propose that the canonical insect tra-dsx pathway evolved via merger between expanding dsx function (from males to both sexes) and narrowing tra function (from a general splicing factor to dedicated regulator of dsx).
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Affiliation(s)
- Judith Wexler
- Department of Evolution and EcologyUniversity of California, DavisDavisUnited States
| | - Emily Kay Delaney
- Department of Evolution and EcologyUniversity of California, DavisDavisUnited States
| | - Xavier Belles
- Institut de Biologia EvolutivaConsejo Superior de Investigaciones Cientificas, Universitat Pompeu FabraBarcelonaSpain
| | - Coby Schal
- Department of Entomology and Plant PathologyNorth Carolina State UniversityRaleighUnited States
| | - Ayako Wada-Katsumata
- Department of Entomology and Plant PathologyNorth Carolina State UniversityRaleighUnited States
| | - Matthew J Amicucci
- Department of ChemistryUniversity of California, DavisDavisUnited States
| | - Artyom Kopp
- Department of Evolution and EcologyUniversity of California, DavisDavisUnited States
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26
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Petrella V, Aceto S, Colonna V, Saccone G, Sanges R, Polanska N, Volf P, Gradoni L, Bongiorno G, Salvemini M. Identification of sex determination genes and their evolution in Phlebotominae sand flies (Diptera, Nematocera). BMC Genomics 2019; 20:522. [PMID: 31238870 PMCID: PMC6593557 DOI: 10.1186/s12864-019-5898-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 06/11/2019] [Indexed: 11/10/2022] Open
Abstract
Background Phlebotomine sand flies (Diptera, Nematocera) are important vectors of several pathogens, including Leishmania parasites, causing serious diseases of humans and dogs. Despite their importance as disease vectors, most aspects of sand fly biology remain unknown including the molecular basis of their reproduction and sex determination, aspects also relevant for the development of novel vector control strategies. Results Using comparative genomics/transcriptomics data mining and transcriptional profiling, we identified the sex determining genes in phlebotomine sand flies and proposed the first model for the sex determination cascade of these insects. For all the genes identified, we produced manually curated gene models, developmental gene expression profile and performed evolutionary molecular analysis. We identified and characterized, for the first time in a Nematocera species, the transformer (tra) homolog which exhibits both conserved and novel features. The analysis of the tra locus in sand flies and its expression pattern suggest that this gene is able to autoregulate its own splicing, as observed in the fruit fly Ceratitis capitata and several other insect species. Conclusions Our results permit to fill the gap about sex determination in sand flies, contribute to a better understanding of this developmental pathway in Nematocera and open the way for the identification of sex determining orthologs in other species of this important Diptera sub-order. Furthermore, the sex determination genes identified in our work also provide the opportunity of future biotechnological applications to control natural population of sand flies, reducing their impact on public health. Electronic supplementary material The online version of this article (10.1186/s12864-019-5898-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Valeria Petrella
- Department of Biology, University of Naples Federico II, Naples, Italy
| | - Serena Aceto
- Department of Biology, University of Naples Federico II, Naples, Italy
| | - Vincenza Colonna
- National Research Council, Institute of Genetics and Biophysics, Naples, Italy
| | - Giuseppe Saccone
- Department of Biology, University of Naples Federico II, Naples, Italy
| | - Remo Sanges
- Stazione Zoologica "Anton Dohrn", Naples, Italy.,Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Italy
| | - Nikola Polanska
- Department of Parasitology, Charles University, Prague, Czech Republic
| | - Petr Volf
- Department of Parasitology, Charles University, Prague, Czech Republic
| | - Luigi Gradoni
- Unit of Vector-borne Diseases, Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Gioia Bongiorno
- Unit of Vector-borne Diseases, Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Marco Salvemini
- Department of Biology, University of Naples Federico II, Naples, Italy.
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27
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Li X, Jin B, Dong Y, Chen X, Tu Z, Gu J. Two of the three Transformer-2 genes are required for ovarian development in Aedes albopictus. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2019; 109:92-105. [PMID: 30914323 PMCID: PMC6636634 DOI: 10.1016/j.ibmb.2019.03.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 03/18/2019] [Accepted: 03/21/2019] [Indexed: 05/23/2023]
Abstract
In Drosophila melanogaster, transformer-2 (tra2) plays an essential role in the sex-specific splicing of doublesex (dsx) and fruitless (fru), two key transcription factor genes that program sexual differentiation and regulate sexual behavior. In the present study, the sequences and expression profiles of three tra2 (Aalbtra2) genes in the Asian tiger mosquito, Aedes albopictus (Ae. albopictus) were characterized. Phylogenetic analysis revealed that these paralogs resulted from two duplication events. The first occurred in the common ancestor of Culicidae, giving rise to the tra2-α and tra2-β clades that are found across divergent mosquito genera, including Aedes, Culex, and Anopheles. The second occurred within the tra2-α clade, giving rise to tra2-γ in Ae. albopictus. In addition to the conserved RNA recognition motif (RRM), arginine-rich/serine-rich regions (RS domains) and a linker region, a glycine-rich region located between the RRM and RS2 was observed in Tra2-α and Tra2-γ of Ae. albopictus that has not yet been described in the Tra2 proteins of dipteran insects. Quantitative real-time PCR detected relatively high levels of transcripts from all three tra2 paralogs in 0-2 h embryos, suggesting maternal deposition of these transcripts. All three Aalbtra2 genes were highly expressed in the ovary, while Aalbtra2-β was also highly expressed in the testis. RNAi-mediated knockdown of any or all Aalbtra2 genes did not result in an obvious switch of the sex-specificity in dsx and fru splicing in the whole-body samples. However, knockdown of transcripts from all three tra2 genes significantly reduced the female isoform of dsx mRNA and increased the male isoform of the dsx mRNA in both the ovary and the fat body in adult females. Furthermore, knockdown of either Aalbtra2-α or Aalbtra2-γ or all three Aalbtra2 led to a decrease in ovariole number and ovary size after a blood meal. Taken together, these results indicate that two of the three tra2 genes affect female ovarian development.
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Affiliation(s)
- Xiaocong Li
- Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Pathogen Biology, School of Public Health, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Binbin Jin
- Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Pathogen Biology, School of Public Health, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Yunqiao Dong
- Reproductive Medical Centre of Guangdong Women and Children Hospital, Guangzhou, Guangdong, 511442, China
| | - Xiaoguang Chen
- Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Pathogen Biology, School of Public Health, Southern Medical University, Guangzhou, Guangdong, 510515, China.
| | - Zhijian Tu
- Department of Biochemistry, Virginia Tech, Blacksburg, VA, 24060, USA
| | - Jinbao Gu
- Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Pathogen Biology, School of Public Health, Southern Medical University, Guangzhou, Guangdong, 510515, China.
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28
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Morita S, Ando T, Maeno A, Mizutani T, Mase M, Shigenobu S, Niimi T. Precise staging of beetle horn formation in Trypoxylus dichotomus reveals the pleiotropic roles of doublesex depending on the spatiotemporal developmental contexts. PLoS Genet 2019; 15:e1008063. [PMID: 30969957 PMCID: PMC6457530 DOI: 10.1371/journal.pgen.1008063] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 03/03/2019] [Indexed: 11/19/2022] Open
Abstract
Many scarab beetles have sexually dimorphic exaggerated horns that are an evolutionary novelty. Since the shape, number, size, and location of horns are highly diverged within Scarabaeidae, beetle horns are an attractive model for studying the evolution of sexually dimorphic and novel traits. In beetles including the Japanese rhinoceros beetle Trypoxylus dichotomus, the sex differentiation gene doublesex (dsx) plays a crucial role in sexually dimorphic horn formation during larval-pupal development. However, knowledge of when and how dsx drives the gene regulatory network (GRN) for horn formation to form sexually dimorphic horns during development remains elusive. To address this issue, we identified a Trypoxylus-ortholog of the sex determination gene, transformer (tra), that regulates sex-specific splicing of the dsx pre-mRNA, and whose loss of function results in sex transformation. By knocking down tra function at multiple developmental timepoints during larval-pupal development, we estimated the onset when the sex-specific GRN for horn formation is driven. In addition, we also revealed that dsx regulates different aspects of morphogenetic activities during the prepupal and pupal developmental stages to form appropriate morphologies of pupal head and thoracic horn primordia as well as those of adult horns. Based on these findings, we discuss the evolutionary developmental background of sexually dimorphic trait growth in horned beetles. Beetles in the family Scarabaeidae have various types of horns on their heads and thoraces, and the shape, size, number, and location of these horns are highly diversified within the group. In addition, many scarab beetle horns are sexually dimorphic. The acquisition of these evolutionarily novel horns, and the mechanisms for the diversification of these structures is an interesting question. To address this question, we focused on the rhinoceros beetle Tripoxylus dichotomus. Here we identified the exact developmental timepoints during which the morphological sexual dimorphism of horn primordia appears, estimated the onset of the developmental program for sexually dimorphic horn formation driven by doublesex, and revealed that doublesex regulates different aspects of cell activities during horn formation depending on particular spatiotemporal developmental contexts. Our study provides insights into regulatory shifts in these mechanisms during the evolution of sexually dimorphic traits in horned beetles.
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Affiliation(s)
- Shinichi Morita
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki, Japan
| | - Toshiya Ando
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki, Japan
- Department of Basic Biology, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), 38 Nishigonaka, Myodaiji, Okazaki, Japan
| | - Akiteru Maeno
- Mammalian Genetics Laboratory, Genetic Strains Research Center, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Takeshi Mizutani
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki, Japan
| | - Mutsuki Mase
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki, Japan
- Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya, Japan
| | - Shuji Shigenobu
- Department of Basic Biology, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), 38 Nishigonaka, Myodaiji, Okazaki, Japan
- NIBB Core Research Facilities, National Institute for Basic Biology, 38 Nishigonaka Myodaiji, Okazaki, Japan
| | - Teruyuki Niimi
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki, Japan
- Department of Basic Biology, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), 38 Nishigonaka, Myodaiji, Okazaki, Japan
- Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya, Japan
- * E-mail:
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29
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Guo L, Xu YH, Zhang N, Zhou FL, Huang JH, Liu BS, Jiang SG, Zhang DC. A High-Density Genetic Linkage Map and QTL Mapping for Sex in Black Tiger Shrimp ( Penaeus monodon). Front Genet 2019; 10:326. [PMID: 31024632 PMCID: PMC6465554 DOI: 10.3389/fgene.2019.00326] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 03/26/2019] [Indexed: 12/20/2022] Open
Abstract
The black tiger shrimp, Penaeus monodon, is important in both fishery and aquaculture and is the second-most widely cultured shrimp species in the world. However, the current strains cannot meet the market needs in various cultural environments, and the genome resources for P. monodon are still lacking. Restriction-site associated DNA sequencing (RADseq) has been widely used in genetic linkage map construction and in quantitative trait loci (QTL) mapping. We constructed a high-density genetic linkage map with RADseq in a full-sib family. This map contained 6524 single nucleotide polymorphisms (SNPs) and 2208 unique loci. The total length was 3275.4 cM, and the genetic distance was estimated to be 1.1 Mb/cM. The sex trait is a dichotomous phenotype, and the same interval was detected as a QTL using QTL mapping and genome-wide association analysis. The most significant locus explained 77.4% of the phenotype variance. The sex locus was speculated to be the same in this species based on the sequence alignments in Mozambique, India, and Hawaii populations. The constructed genetic linkage map provided a valuable resource for QTL mapping, genome assembly, and genome comparison for shrimp. The demonstrated common sex locus is a step closer to locating the underlying gene.
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Affiliation(s)
- Liang Guo
- Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China.,Guangdong Provincial Engineer Technology Research Center of Marine Biological Seed Industry, Guangzhou, China
| | - Yu-Hui Xu
- Biomarker Technologies Corporation, Beijing, China
| | - Nan Zhang
- Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China.,Guangdong Provincial Engineer Technology Research Center of Marine Biological Seed Industry, Guangzhou, China
| | - Fa-Lin Zhou
- Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China.,Guangdong Provincial Engineer Technology Research Center of Marine Biological Seed Industry, Guangzhou, China
| | - Jian-Hua Huang
- Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China.,Guangdong Provincial Engineer Technology Research Center of Marine Biological Seed Industry, Guangzhou, China
| | - Bao-Suo Liu
- Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China.,Guangdong Provincial Engineer Technology Research Center of Marine Biological Seed Industry, Guangzhou, China
| | - Shi-Gui Jiang
- Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China.,Guangdong Provincial Engineer Technology Research Center of Marine Biological Seed Industry, Guangzhou, China
| | - Dian-Chang Zhang
- Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China.,Guangdong Provincial Engineer Technology Research Center of Marine Biological Seed Industry, Guangzhou, China
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30
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Perry C, Scanlan J, Robin C. Mining insect genomes for functionally affiliated genes. CURRENT OPINION IN INSECT SCIENCE 2019; 31:114-122. [PMID: 31109664 DOI: 10.1016/j.cois.2018.12.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 12/21/2018] [Accepted: 12/21/2018] [Indexed: 06/09/2023]
Abstract
Several hundred insect genome assemblies are already publicly available, and this total grows on a weekly basis. A major challenge now confronting insect science is how best to use genomic data to improve our understanding of insect biology. We consider a framework for genome analysis based on functional affiliation, that is, groups of genes involved in the same biological process or pathway, and explore how such an approach furthers our understanding of several aspects of insect phenotype. We anticipate that this approach will prove useful for future research across the breadth of insect studies, whatever organism or trait it involves.
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Affiliation(s)
- Caitlyn Perry
- The University of Melbourne, Parkville, Melbourne, Victoria 3010, Australia.
| | - Jack Scanlan
- The University of Melbourne, Parkville, Melbourne, Victoria 3010, Australia
| | - Charles Robin
- The University of Melbourne, Parkville, Melbourne, Victoria 3010, Australia
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31
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Jia LY, Chen L, Keller L, Wang J, Xiao JH, Huang DW. Doublesex Evolution Is Correlated with Social Complexity in Ants. Genome Biol Evol 2018; 10:3230-3242. [PMID: 30476039 PMCID: PMC6300070 DOI: 10.1093/gbe/evy250] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/09/2018] [Indexed: 12/13/2022] Open
Abstract
The Dmrt (doublesex and mab-3-related transcription factor) genes are transcription factors crucial for sex determination and sexual differentiation. In some social insects, doublesex (dsx) exhibits widespread caste-specific expression across different tissues and developmental stages and has been suggested as a candidate gene for regulating division of labor in social insects. We therefore conducted a molecular evolution analysis of the Dmrt gene family in 20 ants. We found that the insect-specific oligomerization domain of DSX, oligomerization domain 2, was absent in all ants, except for the two phylogenetically basal ant species (Ponerinae), whose social structure and organization resemble the presumed ancestral condition in ants. Phylogenetic reconstruction and selection analysis revealed that dsx evolved faster than the other three members of the Dmrt family. We found evidence for positive selection for dsx in the ant subfamilies with more advanced social organization (Myrmicinae and Formicinae), but not in the Ponerinae. Furthermore, we detected expression of two Dmrt genes, dsx and DMRT11E, in adult ants, and found a clear male-biased expression pattern of dsx in most species for which data are available. Interestingly, we did not detect male-biased expression of dsx in the two ant species that possess a genetic caste determination system. These results possibly suggest an association between the evolution of dsx and social organization as well as reproductive division of labor in ants.
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Affiliation(s)
- Ling-Yi Jia
- Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Li Chen
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Laurent Keller
- Department of Ecology and Evolution, Biophore, University of Lausanne, Switzerland
| | - John Wang
- Biodiversity Research Center, Academia Sinica, Taipei, Taiwan
| | - Jin-Hua Xiao
- College of Life Sciences, Nankai University, Tianjin, China
| | - Da-Wei Huang
- Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,College of Life Sciences, Nankai University, Tianjin, China
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Geuverink E, Kraaijeveld K, van Leussen M, Chen F, Pijpe J, Linskens MHK, Beukeboom LW, van de Zande L. Evidence for involvement of a transformer paralogue in sex determination of the wasp Leptopilina clavipes. INSECT MOLECULAR BIOLOGY 2018; 27:780-795. [PMID: 30039559 DOI: 10.1111/imb.12522] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Transformer (tra) is the central gear in many insect sex determination pathways and transduces a wide range of primary signals. Mediated by transformer-2 (tra2) it directs sexual development into the female or male mode. Duplications of tra have been detected in numerous Hymenoptera, but a function in sex determination has been confirmed only in Apis mellifera. We identified a tra2 orthologue (Lc-tra2), a tra orthologue (Lc-tra) and a tra paralogue (Lc-traB) in the genome of Leptopilina clavipes (Hymenoptera: Cynipidae). We compared the sequence and structural conservation of these genes between sexual (arrhenotokous) and asexual all-female producing (thelytokous) individuals. Lc-tra is sex-specifically spliced in adults consistent with its orthologous function. The male-specific regions of Lc-tra are conserved in both reproductive modes. The paralogue Lc-traB lacks the genomic region coding for male-specific exons and can only be translated into a full-length TRA-like peptide sequence. Furthermore, unlike LC-TRA, the LC-TRAB interstrain sequence variation is not differentiated into a sexual and an asexual haplotype. The LC-TRAB protein interacts with LC-TRA as well as LC-TRA2. This suggests that Lc-traB functions as a conserved element in sex determination of sexual and asexual individuals.
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Affiliation(s)
- E Geuverink
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands
| | - K Kraaijeveld
- Department of Ecological Science, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
- Leiden Genome Technology Center, Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - M van Leussen
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands
| | - F Chen
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands
| | - J Pijpe
- University of Applied Sciences Leiden, Leiden, The Netherlands
| | - M H K Linskens
- Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
| | - L W Beukeboom
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands
| | - L van de Zande
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands
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Schenkel MA, Pen I, Beukeboom LW, Billeter J. Making sense of intralocus and interlocus sexual conflict. Ecol Evol 2018; 8:13035-13050. [PMID: 30619603 PMCID: PMC6309128 DOI: 10.1002/ece3.4629] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 09/17/2018] [Accepted: 09/18/2018] [Indexed: 01/13/2023] Open
Abstract
Sexual conflict occurs because males and females are exposed to different selection pressures. This can affect many aspects of female and male biology, such as physiology, behavior, genetics, and even population ecology. Its broad impact has caused widespread interest in sexual conflict. However, a key aspect of sexual conflict is often confused; it comprises two distinct forms: intralocus and interlocus sexual conflict (IASC and IRSC). Although both are caused by sex differences in selection, they operate via different proximate and ultimate mechanisms. Intralocus sexual conflict and IRSC are often not clearly defined as separate processes in the scientific literature, which impedes a proper understanding of each form as well as of their relative impact on sexual conflict. Furthermore, our current knowledge of the genetics of these phenomena is severely limited. This prevents us from empirically testing numerous theories regarding the role of these two forms of sexual conflict in evolution. Here, we clarify the distinction between IASC and IRSC, by discussing how male and female interests differ, how and when sex-specific adaptation occurs, and how this may lead to evolutionary change. We then describe a framework for their study, focusing on how future experiments may help identify the genetics underlying these phenomena. Through this, we hope to promote a more critical reflection on IASC and IRSC as well as underline the necessity of genetic and mechanistic studies of these two phenomena.
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Affiliation(s)
- Martijn A. Schenkel
- Groningen Institute for Evolutionary Life SciencesUniversity of GroningenGroningenThe Netherlands
| | - Ido Pen
- Groningen Institute for Evolutionary Life SciencesUniversity of GroningenGroningenThe Netherlands
| | - Leo W. Beukeboom
- Groningen Institute for Evolutionary Life SciencesUniversity of GroningenGroningenThe Netherlands
| | - Jean‐Christophe Billeter
- Groningen Institute for Evolutionary Life SciencesUniversity of GroningenGroningenThe Netherlands
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Guo L, Xie W, Liu Y, Yang Z, Yang X, Xia J, Wang S, Wu Q, Zhang Y. Identification and characterization of doublesex in Bemisia tabaci. INSECT MOLECULAR BIOLOGY 2018; 27:620-632. [PMID: 29660189 DOI: 10.1111/imb.12494] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Bemisia tabaci (Gennadius) is an important agricultural pest with a worldwide distribution. Although B. tabaci is known to have a unique haplodiploid reproductive strategy, its sex determination mechanism is largely unknown. In this study, we cloned the full-length sequence of B. tabaci doublesex (Btdsx) and found that Btdsx has 28 splicing isoforms. We found two new splicing isoforms of transformer 2 (Bttra2), which encode two proteins. We also confirmed that both genes lack sex-specific splicing isoforms. Real-time quantitative PCR analysis showed that the expression of Btdsx and Bttra2 is higher in males than in females. RNA interference of Bttra2 affected the expression of Btdsx and vice versa. Furthermore, silencing of Bttra2 or Btdsx caused malformation of the male genitalia (anal style). It did not affect the female phenotype, but reduced the expression of vitellogenin gene in females. These results indicate that Btdsx is associated with sex determination in B. tabaci and that Btdsx and Bttra2 affect each other and are important for male genitalia formation. In addition to increasing our understanding of the roles of dsx and tra2 in the sex determination of B. tabaci, the results will be useful for studies of sex determination in other haplodiploid species.
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Affiliation(s)
- L Guo
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha, Hunan, China
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, China
| | - W Xie
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Y Liu
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Z Yang
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, China
| | - X Yang
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, China
| | - J Xia
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, China
| | - S Wang
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Q Wu
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Y Zhang
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, China
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Consequences of resistance evolution in a Cas9-based sex conversion-suppression gene drive for insect pest management. Proc Natl Acad Sci U S A 2018; 115:6189-6194. [PMID: 29844184 DOI: 10.1073/pnas.1713825115] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The use of a site-specific homing-based gene drive for insect pest control has long been discussed, but the easy design of such systems has become possible only with the recent establishment of CRISPR/Cas9 technology. In this respect, novel targets for insect pest management are provided by new discoveries regarding sex determination. Here, we present a model for a suppression gene drive designed to cause an all-male population collapse in an agricultural pest insect. To evaluate the molecular details of such a sex conversion-based suppression gene drive experimentally, we implemented this strategy in Drosophila melanogaster to serve as a safe model organism. We generated a Cas9-based homing gene-drive element targeting the transformer gene and showed its high efficiency for sex conversion from females to males. However, nonhomologous end joining increased the rate of mutagenesis at the target site, which resulted in the emergence of drive-resistant alleles and therefore curbed the gene drive. This confirms previous studies that simple homing CRISPR/Cas9 gene-drive designs will be ineffective. Nevertheless, by performing population dynamics simulations using the parameters we obtained in D. melanogaster and by adjusting the model for the agricultural pest Ceratitis capitata, we were able to identify adequate modifications that could be successfully applied for the management of wild Mediterranean fruit fly populations using our proposed sex conversion-based suppression gene-drive strategy.
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36
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Geuverink E, Verhulst EC, van Leussen M, van de Zande L, Beukeboom LW. Maternal provision of non-sex-specific transformer messenger RNA in sex determination of the wasp Asobara tabida. INSECT MOLECULAR BIOLOGY 2018; 27:99-109. [PMID: 29030993 DOI: 10.1111/imb.12352] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In many insect species maternal provision of sex-specifically spliced messenger RNA (mRNA) of sex determination genes is an essential component of the sex determination mechanism. In haplodiploid Hymenoptera, maternal provision in combination with genomic imprinting has been shown for the parasitoid Nasonia vitripennis, known as maternal effect genomic imprinting sex determination (MEGISD). Here, we characterize the sex determination cascade of Asobara tabida, another hymenopteran parasitoid. We show the presence of the conserved sex determination genes doublesex (dsx), transformer (tra) and transformer-2 (tra2) orthologues in As. tabida. Of these, At-dsx and At-tra are sex-specifically spliced, indicating a conserved function in sex determination. At-tra and At-tra2 mRNA is maternally provided to embryos but, in contrast to most studied insects, As. tabida females transmit a non-sex-specific splice form of At-tra mRNA to the eggs. In this respect, As. tabida sex determination differs from the MEGISD mechanism. How the paternal genome can induce female development in the absence of maternal provision of sex-specifically spliced mRNA remains an open question. Our study reports a hitherto unknown variant of maternal effect sex determination and accentuates the diversity of insect sex determination mechanisms.
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Affiliation(s)
- E Geuverink
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands
| | - E C Verhulst
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands
- Laboratory of Genetics, Wageningen University, Wageningen, The Netherlands
| | - M van Leussen
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands
| | - L van de Zande
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands
| | - L W Beukeboom
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands
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37
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Sex Determination Cascade in Insects: A Great Treasure House of Alternative Splicing. DIVERSITY AND COMMONALITY IN ANIMALS 2018. [DOI: 10.1007/978-4-431-56609-0_13] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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38
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Wu C, Jordan MD, Newcomb RD, Gemmell NJ, Bank S, Meusemann K, Dearden PK, Duncan EJ, Grosser S, Rutherford K, Gardner PP, Crowhurst RN, Steinwender B, Tooman LK, Stevens MI, Buckley TR. Analysis of the genome of the New Zealand giant collembolan (Holacanthella duospinosa) sheds light on hexapod evolution. BMC Genomics 2017; 18:795. [PMID: 29041914 PMCID: PMC5644144 DOI: 10.1186/s12864-017-4197-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 10/08/2017] [Indexed: 12/03/2022] Open
Abstract
BACKGROUND The New Zealand collembolan genus Holacanthella contains the largest species of springtails (Collembola) in the world. Using Illumina technology we have sequenced and assembled a draft genome and transcriptome from Holacanthella duospinosa (Salmon). We have used this annotated assembly to investigate the genetic basis of a range of traits critical to the evolution of the Hexapoda, the phylogenetic position of H. duospinosa and potential horizontal gene transfer events. RESULTS Our genome assembly was ~375 Mbp in size with a scaffold N50 of ~230 Kbp and sequencing coverage of ~180×. DNA elements, LTRs and simple repeats and LINEs formed the largest components and SINEs were very rare. Phylogenomics (370,877 amino acids) placed H. duospinosa within the Neanuridae. We recovered orthologs of the conserved sex determination genes thought to play a role in sex determination. Analysis of CpG content suggested the absence of DNA methylation, and consistent with this we were unable to detect orthologs of the DNA methyltransferase enzymes. The small subunit rRNA gene contained a possible retrotransposon. The Hox gene complex was broken over two scaffolds. For chemosensory ability, at least 15 and 18 ionotropic glutamate and gustatory receptors were identified, respectively. However, we were unable to identify any odorant receptors or their obligate co-receptor Orco. Twenty-three chitinase-like genes were identified from the assembly. Members of this multigene family may play roles in the digestion of fungal cell walls, a common food source for these saproxylic organisms. We also detected 59 and 96 genes that blasted to bacteria and fungi, respectively, but were located on scaffolds that otherwise contained arthropod genes. CONCLUSIONS The genome of H. duospinosa contains some unusual features including a Hox complex broken over two scaffolds, in a different manner to other arthropod species, a lack of odorant receptor genes and an apparent lack of environmentally responsive DNA methylation, unlike many other arthropods. Our detection of candidate horizontal gene transfer candidates confirms that this phenomenon is occurring across Collembola. These findings allow us to narrow down the regions of the arthropod phylogeny where key innovations have occurred that have facilitated the evolutionary success of Hexapoda.
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Affiliation(s)
- Chen Wu
- Landcare Research, Private Bag, Auckland, 92170, New Zealand
- School of Biological Sciences, The University of Auckland, Auckland, New Zealand
| | - Melissa D Jordan
- The New Zealand Institute for Plant & Food Research Ltd, Auckland, New Zealand
| | - Richard D Newcomb
- School of Biological Sciences, The University of Auckland, Auckland, New Zealand
- The New Zealand Institute for Plant & Food Research Ltd, Auckland, New Zealand
| | - Neil J Gemmell
- Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Sarah Bank
- Center for Molecular Biodiversity Research, Zoological Research Museum Alexander Koenig, Adenauerallee 160, 53113, Bonn, Germany
| | - Karen Meusemann
- Center for Molecular Biodiversity Research, Zoological Research Museum Alexander Koenig, Adenauerallee 160, 53113, Bonn, Germany
- Evolutionary Biology & Ecology, Institute for Biology, University of Freiburg, Freiburg, Germany
| | - Peter K Dearden
- Genetics Otago, Department of Biochemistry, University of Otago, Dunedin, New Zealand
| | - Elizabeth J Duncan
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Sefanie Grosser
- Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
- Department of Animal Behaviour, Bielefeld University, Bielefeld, Germany
- Division of Evolutionary Biology, Faculty of Biology, Ludwig-Maximilian University of Munich, Planegg-, Martinsried, Germany
| | - Kim Rutherford
- Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Paul P Gardner
- Biomolecular Interactions Centre, School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
| | - Ross N Crowhurst
- The New Zealand Institute for Plant & Food Research Ltd, Auckland, New Zealand
| | - Bernd Steinwender
- School of Biological Sciences, The University of Auckland, Auckland, New Zealand
- The New Zealand Institute for Plant & Food Research Ltd, Auckland, New Zealand
| | - Leah K Tooman
- The New Zealand Institute for Plant & Food Research Ltd, Auckland, New Zealand
| | - Mark I Stevens
- South Australian Museum, North Terrace, GPO Box 234, Adelaide, SA, 5001, Australia
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA, Australia
| | - Thomas R Buckley
- Landcare Research, Private Bag, Auckland, 92170, New Zealand.
- School of Biological Sciences, The University of Auckland, Auckland, New Zealand.
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Sawanth SK, Gopinath G, Sambrani N, Arunkumar KP. The autoregulatory loop: A common mechanism of regulation of key sex determining genes in insects. J Biosci 2017; 41:283-94. [PMID: 27240989 DOI: 10.1007/s12038-016-9609-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Sex determination in most insects is structured as a gene cascade, wherein a primary signal is passed through a series of sex-determining genes, culminating in a downstream double-switch known as doublesex that decides the sexual fate of the embryo. From the literature available on sex determination cascades, it becomes apparent that sex determination mechanisms have evolved rapidly. The primary signal that provides the cue to determine the sex of the embryo varies remarkably, not only among taxa, but also within taxa. Furthermore, the upstream key gene in the cascade also varies between species and even among closely related species. The order Insecta alone provides examples of astoundingly complex diversity of upstream key genes in sex determination mechanisms. Besides, unlike key upstream genes, the downstream double-switch gene is alternatively spliced to form functional sex-specific isoforms. This sex-specific splicing is conserved across insect taxa. The genes involved in the sex determination cascade such as Sex-lethal (Sxl) in Drosophila melanogaster, transformer (tra) in many other dipterans, coleopterans and hymenopterans, Feminizer (fem) in Apis mellifera, and IGF-II mRNA-binding protein (Bmimp) in Bombyx mori are reported to be regulated by an autoregulatory positive feedback loop. In this review, by taking examples from various insects, we propose the hypothesis that autoregulatory loop mechanisms of sex determination might be a general strategy. We also discuss the possible reasons for the evolution of autoregulatory loops in sex determination cascades and their impact on binary developmental choices.
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Affiliation(s)
- Suresh Kumar Sawanth
- Centre of Excellence for Genetics and Genomics of Silkmoths, Laboratory of Molecular Genetics, Centre for DNA Fingerprinting and Diagnostics, Hyderabad 500 001, India
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40
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Ledón-Rettig CC, Zattara EE, Moczek AP. Asymmetric interactions between doublesex and tissue- and sex-specific target genes mediate sexual dimorphism in beetles. Nat Commun 2017; 8:14593. [PMID: 28239147 PMCID: PMC5333360 DOI: 10.1038/ncomms14593] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 01/11/2017] [Indexed: 12/29/2022] Open
Abstract
Sexual dimorphisms fuel significant intraspecific variation and evolutionary diversification. Yet the developmental-genetic mechanisms underlying sex-specific development remain poorly understood. Here, we focus on the conserved sex-determination gene doublesex (dsx) and the mechanisms by which it mediates sex-specific development in a horned beetle species by combining systemic dsx knockdown, high-throughput sequencing of diverse tissues and a genome-wide analysis of Dsx-binding sites. We find that Dsx regulates sex-biased expression predominantly in males, that Dsx's target repertoires are highly sex- and tissue-specific and that Dsx can exercise its regulatory role via two distinct mechanisms: as a sex-specific modulator by regulating strictly sex-specific targets, or as a switch by regulating the same genes in males and females in opposite directions. More generally, our results suggest Dsx can rapidly acquire new target gene repertoires to accommodate evolutionarily novel traits, evidenced by the large and unique repertoire identified in head horns, a recent morphological innovation.
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Affiliation(s)
- C. C. Ledón-Rettig
- Department of Biology, Indiana University, 915 E. Third Street, Myers Hall 150, Bloomington, Indiana 47405-7107, USA
| | - E. E. Zattara
- Department of Biology, Indiana University, 915 E. Third Street, Myers Hall 150, Bloomington, Indiana 47405-7107, USA
| | - A. P. Moczek
- Department of Biology, Indiana University, 915 E. Third Street, Myers Hall 150, Bloomington, Indiana 47405-7107, USA
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41
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Xu J, Zhan S, Chen S, Zeng B, Li Z, James AA, Tan A, Huang Y. Sexually dimorphic traits in the silkworm, Bombyx mori, are regulated by doublesex. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2017; 80:42-51. [PMID: 27867075 DOI: 10.1016/j.ibmb.2016.11.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 10/19/2016] [Accepted: 11/16/2016] [Indexed: 06/06/2023]
Abstract
The DM domain genes, doublesex (dsx) in insects, or their structural homologs, male abnormal 3 (mab-3) in nematodes and Dmrt1 (doublesex and mab-3-related transcription factor 1) in mammals, are downstream regulators of the sex determination pathway that control sexually dimorphic development. Despite the functional importance of dsx and its potential applications in sterile insect technologies (SITs), the mechanisms by which it controls sexually dimorphic traits and the subsequent developmental gene networks in insects are poorly understood. Phylogenetic analyses indicate that insect dsx genes have sex-specific alternative splicing isoforms, whereas other taxa do not. We exploited genome editing and transgenesis technologies to induce mutations in either the male-specific isoform (dsxM) or common region (dsxC) of dsx in the somatic tissues of the lepidopteran model insect Bombyx mori. Disruptions of gene function produced either male-specific sexually-dimorphic defects or intersexual phenotypes; these results differ from those observed in other insects, including Drosophila melanogaster. Our data provide insights into the divergence of the insect sex determination pathways related to the most conserved downstream component dsx.
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Affiliation(s)
- Jun Xu
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shuai Zhan
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Shuqing Chen
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Baosheng Zeng
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhiqian Li
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Anthony A James
- Department of Microbiology & Molecular Genetics and Molecular Biology & Biochemistry, University of California, Irvine, CA 92697-3900, United States.
| | - Anjiang Tan
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China.
| | - Yongping Huang
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China.
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Mine S, Sumitani M, Aoki F, Hatakeyama M, Suzuki MG. Identification and functional characterization of the sex-determining gene doublesex in the sawfly, Athalia rosae (Hymenoptera: Tenthredinidae). APPLIED ENTOMOLOGY AND ZOOLOGY 2017; 52:497-509. [PMID: 28798494 PMCID: PMC5524875 DOI: 10.1007/s13355-017-0502-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 05/18/2017] [Indexed: 05/22/2023]
Abstract
Sexual fate of the sawfly, Athalia rosae (Hymenoptera: Tenthredinidae) is determined by the complementary sex determination (CSD) mechanism as is the case in honeybees. However, to date, genes involved in sex determination have not been identified in this species. In this study, we attempted to identify orthologs of complementary sex-determiner (csd), feminizer (fem), and doublesex (dsx) from the A. rosae genome, all of which are crucial components of the sex determination cascade in the honeybee. As a result, we identified a sawfly ortholog of dsx (designated as Ardsx). Rapid amplification of cDNA ends (RACE) using total RNA extracted from male and female larvae identified three male-specific variants and three female-specific variants. Comparison between the full-length Ardsx cDNAs and the genomic sequence revealed that exon 5 was differentially spliced between the male- and female-specific variants. RT-PCR analysis demonstrated that Ardsx pre-mRNA was spliced alternatively in a sex-dependent manner at almost all the developmental stages. RNAi-mediated knockdown of Ardsx in males caused severe defects in the reproductive organs and, notably, induced development of the ovipository apparatus containing the dorsal pair of blades and the sheath. These males also showed abnormalities in testes and seminal vesicles and lacked mature sperm. The present study provides the first direct evidence that dsx is essential for sexual development in hymenopteran species.
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Affiliation(s)
- Shotaro Mine
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba, 277-8562 Japan
| | - Megumi Sumitani
- Genetically Modified Organism Research Center, National Institute of Agrobiological Sciences, Owashi, Tsukuba, 305-8634 Japan
| | - Fugaku Aoki
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba, 277-8562 Japan
| | - Masatsugu Hatakeyama
- Division of Insect Sciences, National Institute of Agrobiological Sciences, Owashi, Tsukuba, 305-8634 Japan
| | - Masataka G. Suzuki
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba, 277-8562 Japan
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Luo Y, Zhao S, Li J, Li P, Yan R. Isolation and Molecular Characterization of the Transformer Gene From Bactrocera cucurbitae (Diptera: Tephritidae). JOURNAL OF INSECT SCIENCE (ONLINE) 2017; 17:3755290. [PMID: 28931159 PMCID: PMC5469387 DOI: 10.1093/jisesa/iex031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Indexed: 05/13/2023]
Abstract
transformer (tra) is a switch gene of sex determination in many insects, particularly in Dipterans. However, the sex determination pathway in Bactrocera cucurbitae (Coquillett), a very destructive pest on earth, remains largely uncharacterized. In this study, we have isolated and characterized one female-specific and two male-specific transcripts of the tra gene (Bcutra) of B. cucurbitae. The genomic structure of Bcutra has been determined and the presence of multiple conserved Transformer (TRA)/TRA-2 binding sites in Bcutra has been found. BcuTRA is highly conservative with its homologues in other tephritid fruit flies. Gene expression analysis of Bcutra at different developmental stages demonstrates that the female transcript of Bcutra appears earlier than the male counterparts, indicating that the maternal TRA is inherited in eggs and might play a role in the regulation of TRA expression. The conservation of protein sequence and sex-specific splicing of Bcutra and its expression patterns during development suggest that Bcutra is probably the master gene of sex determination of B. cucurbitae. Isolation of Bcutra will facilitate the development of a genetic sexing strain for its biological control.
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Affiliation(s)
- Ya Luo
- Department of Plant Protection, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, Hainan Province, China (; ; ; ; )Corresponding author, e-mail: , and
| | - Santao Zhao
- Department of Plant Protection, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, Hainan Province, China (; ; ; ; )Corresponding author, e-mail: , and
| | - Jiahui Li
- Department of Plant Protection, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, Hainan Province, China (; ; ; ; )Corresponding author, e-mail: , and
| | - Peizheng Li
- Department of Plant Protection, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, Hainan Province, China (; ; ; ; )Corresponding author, e-mail: , and
| | - Rihui Yan
- Department of Plant Protection, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, Hainan Province, China (; ; ; ; )Corresponding author, e-mail: , and
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, Hainan University, Haikou, Hainan Province, China ()
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Mannino MC, Rivarola M, Scannapieco AC, González S, Farber M, Cladera JL, Lanzavecchia SB. Transcriptome profiling of Diachasmimorpha longicaudata towards useful molecular tools for population management. BMC Genomics 2016; 17:793. [PMID: 27729028 PMCID: PMC5059965 DOI: 10.1186/s12864-016-2759-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 05/21/2016] [Indexed: 12/05/2022] Open
Abstract
Background Diachasmimorpha longicaudata (Hymenoptera: Braconidae) is a solitary parasitoid of Tephritidae (Diptera) fruit flies of economic importance currently being mass-reared in bio-factories and successfully used worldwide. A peculiar biological aspect of Hymenoptera is its haplo-diploid life cycle, where females (diploid) develop from fertilized eggs and males (haploid) from unfertilized eggs. Diploid males were described in many species and recently evidenced in D. longicaudata by mean of inbreeding studies. Sex determination in this parasitoid is based on the Complementary Sex Determination (CSD) system, with alleles from at least one locus involved in early steps of this pathway. Since limited information is available about genetics of this parasitoid species, a deeper analysis on D. longicaudata’s genomics is required to provide molecular tools for achieving a more cost effective production under artificial rearing conditions. Results We report here the first transcriptome analysis of male-larvae, adult females and adult males of D. longicaudata using 454-pyrosequencing. A total of 469766 reads were analyzed and 8483 high-quality isotigs were assembled. After functional annotation, a total of 51686 unigenes were produced, from which, 7021 isotigs and 20227 singletons had at least one BLAST hit against the NCBI non-redundant protein database. A preliminary comparison of adult female and male evidenced that 98 transcripts showed differential expression profiles, with at least a 10-fold difference. Among the functionally annotated transcripts we detected four sequences potentially involved in sex determination and three homologues to two known genes involved in the sex determination cascade. Finally, a total of 4674SimpleSequence Repeats (SSRs) were in silico identified and characterized. Conclusion The information obtained here will significantly contribute to the development of D. longicaudata functional genomics, genetics and population-based genome studies. Thousands of new microsatellite markers were identified as toolkits for population genetics analysis. The transcriptome characterized here is the starting point to elucidate the molecular bases of the sex determination mechanism in this species. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-2759-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- M Constanza Mannino
- Laboratorio de Insectos de Importancia Económica, Instituto de Genética Ewald A. Favret, Instituto Nacional de Tecnología Agropecuaria (INTA), Hurlingham, Buenos Aires, Argentina. .,Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina.
| | - Máximo Rivarola
- Instituto de Biotecnología, Instituto Nacional de Tecnología Agropecuaria (INTA), Hurlingham, Buenos Aires, Argentina.,Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Alejandra C Scannapieco
- Laboratorio de Insectos de Importancia Económica, Instituto de Genética Ewald A. Favret, Instituto Nacional de Tecnología Agropecuaria (INTA), Hurlingham, Buenos Aires, Argentina.,Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Sergio González
- Instituto de Biotecnología, Instituto Nacional de Tecnología Agropecuaria (INTA), Hurlingham, Buenos Aires, Argentina.,Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Marisa Farber
- Instituto de Biotecnología, Instituto Nacional de Tecnología Agropecuaria (INTA), Hurlingham, Buenos Aires, Argentina.,Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Jorge L Cladera
- Laboratorio de Insectos de Importancia Económica, Instituto de Genética Ewald A. Favret, Instituto Nacional de Tecnología Agropecuaria (INTA), Hurlingham, Buenos Aires, Argentina
| | - Silvia B Lanzavecchia
- Laboratorio de Insectos de Importancia Económica, Instituto de Genética Ewald A. Favret, Instituto Nacional de Tecnología Agropecuaria (INTA), Hurlingham, Buenos Aires, Argentina
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Collet M, Vayssade C, Auguste A, Mouton L, Desouhant E, Malausa T, Fauvergue X. Diploid male production correlates with genetic diversity in the parasitoid wasp Venturia canescens: a genetic approach with new microsatellite markers. Ecol Evol 2016; 6:6721-6734. [PMID: 27777743 PMCID: PMC5058541 DOI: 10.1002/ece3.2370] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 07/12/2016] [Accepted: 07/18/2016] [Indexed: 11/06/2022] Open
Abstract
Sex determination is ruled by haplodiploidy in Hymenoptera, with haploid males arising from unfertilized eggs and diploid females from fertilized eggs. However, diploid males with null fitness are produced under complementary sex determination (CSD), when individuals are homozygous for this locus. Diploid males are expected to be more frequent in genetically eroded populations (such as islands and captive populations), as genetic diversity at the csd locus should be low. However, only a few studies have focused on the relation between population size, genetic diversity, and the proportion of diploid males in the field. Here, we developed new microsatellite markers in order to assess and compare genetic diversity and diploid male proportion (DMP) in populations from three distinct habitat types - mainland, island, or captive -, in the parasitoid wasp Venturia canescens. Eroded genetic diversity and higher DMP were found in island and captive populations, and habitat type had large effect on genetic diversity. Therefore, DMP reflects the decreasing genetic diversity in small and isolated populations. Thus, Hymenopteran populations can be at high extinction risk due to habitat destruction or fragmentation.
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Affiliation(s)
- Marie Collet
- Laboratoire de Biométrie et Biologie Evolutive UMR 5558CNRSUniversité Claude BernardUniversité de LyonF‐69622VilleurbanneFrance
| | - Chloé Vayssade
- UMR 1355‐7254 Institut Sophia AgrobiotechCNRSUniversité Nice Sophia AntipolisINRA06900Sophia AntipolisFrance
| | - Alexandra Auguste
- UMR 1355‐7254 Institut Sophia AgrobiotechCNRSUniversité Nice Sophia AntipolisINRA06900Sophia AntipolisFrance
| | - Laurence Mouton
- Laboratoire de Biométrie et Biologie Evolutive UMR 5558CNRSUniversité Claude BernardUniversité de LyonF‐69622VilleurbanneFrance
| | - Emmanuel Desouhant
- Laboratoire de Biométrie et Biologie Evolutive UMR 5558CNRSUniversité Claude BernardUniversité de LyonF‐69622VilleurbanneFrance
| | - Thibaut Malausa
- UMR 1355‐7254 Institut Sophia AgrobiotechCNRSUniversité Nice Sophia AntipolisINRA06900Sophia AntipolisFrance
| | - Xavier Fauvergue
- UMR 1355‐7254 Institut Sophia AgrobiotechCNRSUniversité Nice Sophia AntipolisINRA06900Sophia AntipolisFrance
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Sakai H, Sumitani M, Chikami Y, Yahata K, Uchino K, Kiuchi T, Katsuma S, Aoki F, Sezutsu H, Suzuki MG. Transgenic Expression of the piRNA-Resistant Masculinizer Gene Induces Female-Specific Lethality and Partial Female-to-Male Sex Reversal in the Silkworm, Bombyx mori. PLoS Genet 2016; 12:e1006203. [PMID: 27579676 PMCID: PMC5007099 DOI: 10.1371/journal.pgen.1006203] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 06/28/2016] [Indexed: 12/12/2022] Open
Abstract
In Bombyx mori (B. mori), Fem piRNA originates from the W chromosome and is responsible for femaleness. The Fem piRNA-PIWI complex targets and cleaves mRNAs transcribed from the Masc gene. Masc encodes a novel CCCH type zinc-finger protein and is required for male-specific splicing of B. mori doublesex (Bmdsx) transcripts. In the present study, several silkworm strains carrying a transgene, which encodes a Fem piRNA-resistant Masc mRNA (Masc-R), were generated. Forced expression of the Masc-R transgene caused female-specific lethality during the larval stages. One of the Masc-R strains weakly expressed Masc-R in various tissues. Females heterozygous for the transgene expressed male-specific isoform of the Bombyx homolog of insulin-like growth factor II mRNA-binding protein (ImpM) and Bmdsx. All examined females showed a lower inducibility of vitellogenin synthesis and exhibited abnormalities in the ovaries. Testis-like tissues were observed in abnormal ovaries and, notably, the tissues contained considerable numbers of sperm bundles. Homozygous expression of the transgene resulted in formation of the male-specific abdominal segment in adult females and caused partial male differentiation in female genitalia. These results strongly suggest that Masc is an important regulatory gene of maleness in B. mori.
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Affiliation(s)
- Hiroki Sakai
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba 277-8562, Japan
| | - Megumi Sumitani
- Transgenic Silkworm Research Unit, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), Owashi, Tsukuba, Ibaraki 305-8634, Japan
| | - Yasuhiko Chikami
- Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan
| | - Kensuke Yahata
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan
| | - Keiro Uchino
- Transgenic Silkworm Research Unit, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), Owashi, Tsukuba, Ibaraki 305-8634, Japan
| | - Takashi Kiuchi
- Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Susumu Katsuma
- Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Fugaku Aoki
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba 277-8562, Japan
| | - Hideki Sezutsu
- Transgenic Silkworm Research Unit, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), Owashi, Tsukuba, Ibaraki 305-8634, Japan
| | - Masataka G. Suzuki
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba 277-8562, Japan
- * E-mail:
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Jia LY, Xiao JH, Xiong TL, Niu LM, Huang DW. The transformer genes in the fig wasp Ceratosolen solmsi provide new evidence for duplications independent of complementary sex determination. INSECT MOLECULAR BIOLOGY 2016; 25:191-201. [PMID: 26748889 DOI: 10.1111/imb.12210] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Transformer (tra) is the key gene that turns on the sex-determination cascade in Drosophila melanogaster and in some other insects. The honeybee Apis mellifera has two duplicates of tra, one of which (complementary sex determiner, csd) is the primary signal for complementary sex-determination (CSD), regulating the other duplicate (feminizer). Two tra duplicates have been found in some other hymenopteran species, resulting in the assumption that a single ancestral duplication of tra took place in the Hymenoptera. Here, we searched for tra homologues and pseudogenes in the Hymenoptera, focusing on five newly published hymenopteran genomes. We found three tra copies in the fig wasp Ceratosolen solmsi. Further evolutionary and expression analyses also showed that the two duplicates (Csoltra-B and Csoltra-C) are under positive selection, and have female-specific expression, suggesting possible sex-related functions. Moreover, Aculeata species exhibit many pseudogenes generated by lineage-specific duplications. We conclude that phylogenetic reconstruction and pseudogene screening provide novel evidence supporting the hypothesis of independent duplications rather an ancestral origin of multiple tra paralogues in the Hymenoptera. The case of C. solmsi is the first example of a non-CSD species with duplicated tra, contrary to the previous assumption that derived tra paralogues function as the CSD locus.
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Affiliation(s)
- L-Y Jia
- Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - J-H Xiao
- Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - T-L Xiong
- Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - L-M Niu
- Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Danzhou, Hainan, China
| | - D-W Huang
- Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- Plant Protection College, Shandong Agricultural University, Tai'an, China
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Expression profile of the sex determination gene doublesex in a gynandromorph of bumblebee, Bombus ignitus. Naturwissenschaften 2016; 103:17. [DOI: 10.1007/s00114-016-1342-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 01/27/2016] [Accepted: 02/03/2016] [Indexed: 01/28/2023]
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Laohakieat K, Aketarawong N, Isasawin S, Thitamadee S, Thanaphum S. The study of the transformer gene from Bactrocera dorsalis and B. correcta with putative core promoter regions. BMC Genet 2016; 17:34. [PMID: 26833079 PMCID: PMC4736151 DOI: 10.1186/s12863-016-0342-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 01/25/2016] [Indexed: 12/31/2022] Open
Abstract
Background The transformer (tra) is a sex determining switch in different orders of insects, including Diptera, as in the family Tephritidae. The lifelong autoregulatory loop of tra female-specific splicing can be reset by the intervention of male-specific primary signals (M factor). In early development, the functional female and truncated male TRA proteins relay the sexual fates to the alternative splicing of a bisexual switch gene, doublesex (dsx) cascading the sexual differentiation processes. Bactrocera dorsalis (Hendel) and Bactrocera correcta (Bezzi) are among the Bactrocera model worldwide key pests. Area-wide integrated pest management using the male-only Sterile Insect Technique (SIT) relying on genetic sexing systems is effective in control programs. We undertook the molecular characterization and comparative studies of the tra orthologues in the Bactrocera species, including the Salaya1 genetic sexing strain (GSS). Results RT-PCR revealed that B. dorsalis tra (Bdtra) and B. correcta tra (Bctra) transcripts contained conservation of both constitutive exons and male-specific exons as in other Bactrocera. However, new Bdtra male-specific exons were retained, diversifying the pattern of the male-specifically spliced transcripts. The coding sequences of tra were highly conserved in Bactrocera (86–95 %) but less so among related genera (61–65 %) within the same Tephritidae family. A conservation of deduced amino acid sequences (18 residues), called the TEP region, was identified to be distinctive among tephritids. The 5’ regulatory sequence containing many structural characteristics of the putative core promoter was discovered in B. correcta. The expression patterns of Bdtra and Bctra were sex-specifically spliced and the signals relayed to the dsx genes in the adult wild-types. However, the coexistence of male- and female-specifically spliced transcripts (980 and 626 bp, respectively) of the B. dorsalis wild-type strain was found in the Salaya1 GSS adult males. The Bdtra RNA interference masculinized the XX karyotype females into pseudomales, but their testes were mostly not well developed. Conclusions Bdtra and Bctra have sex-specific splicing, similar to Bactroceras, Ceratitis capitata (Wiedemann), and Anastrephas. A newly identified TEP region is proposed in tephritids. A putative core promoter has been discovered in Bctra. Electronic supplementary material The online version of this article (doi:10.1186/s12863-016-0342-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Kamoltip Laohakieat
- Department of Biotechnology, Faculty of Science, Mahidol University, Rama VI Road, Bangkok, 10400, Thailand.
| | - Nidchaya Aketarawong
- Department of Biotechnology, Faculty of Science, Mahidol University, Rama VI Road, Bangkok, 10400, Thailand.
| | - Siriwan Isasawin
- Department of Biotechnology, Faculty of Science, Mahidol University, Rama VI Road, Bangkok, 10400, Thailand.
| | - Siripong Thitamadee
- Department of Biotechnology, Faculty of Science, Mahidol University, Rama VI Road, Bangkok, 10400, Thailand.
| | - Sujinda Thanaphum
- Department of Biotechnology, Faculty of Science, Mahidol University, Rama VI Road, Bangkok, 10400, Thailand.
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Rideout EJ, Narsaiya MS, Grewal SS. The Sex Determination Gene transformer Regulates Male-Female Differences in Drosophila Body Size. PLoS Genet 2015; 11:e1005683. [PMID: 26710087 PMCID: PMC4692505 DOI: 10.1371/journal.pgen.1005683] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Accepted: 10/28/2015] [Indexed: 12/17/2022] Open
Abstract
Almost all animals show sex differences in body size. For example, in Drosophila, females are larger than males. Although Drosophila is widely used as a model to study growth, the mechanisms underlying this male-female difference in size remain unclear. Here, we describe a novel role for the sex determination gene transformer (tra) in promoting female body growth. Normally, Tra is expressed only in females. We find that loss of Tra in female larvae decreases body size, while ectopic Tra expression in males increases body size. Although we find that Tra exerts autonomous effects on cell size, we also discovered that Tra expression in the fat body augments female body size in a non cell-autonomous manner. These effects of Tra do not require its only known targets doublesex and fruitless. Instead, Tra expression in the female fat body promotes growth by stimulating the secretion of insulin-like peptides from insulin producing cells in the brain. Our data suggest a model of sex-specific growth in which body size is regulated by a previously unrecognized branch of the sex determination pathway, and identify Tra as a novel link between sex and the conserved insulin signaling pathway. Female-biased sexual size dimorphism is common in invertebrates, yet the mechanisms underlying increased female body size remain unclear. We uncovered a key role for sex determination gene transformer (tra) in promoting increased growth in females. Interestingly, we found that sex differences in body size are regulated by Tra in a pathway that is separate of the canonical sex determination pathway, and of other aspects of sexual dimorphism. Instead, Tra function in the fat body regulates growth in a non cell-autonomous manner by regulating the secretion of insulin-like peptides from the brain. This novel Tra-insulin link we describe may have implications for other sexually dimorphic phenotypes in Drosophila (eg. lifespan, stress resistance), many of which are also regulated by insulin.
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Affiliation(s)
- Elizabeth J. Rideout
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, Alberta, Canada
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, British Columbia, Canada
- * E-mail: (EJR); (SSG)
| | - Marcus S. Narsaiya
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Savraj S. Grewal
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, Alberta, Canada
- * E-mail: (EJR); (SSG)
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