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van’t Hof AE, Whiteford S, Yung CJ, Yoshido A, Zrzavá M, de Jong MA, Tan KL, Zhu D, Monteiro A, Brakefield PM, Marec F, Saccheri IJ. Zygosity-based sex determination in a butterfly drives hypervariability of Masculinizer. SCIENCE ADVANCES 2024; 10:eadj6979. [PMID: 38701204 PMCID: PMC11067997 DOI: 10.1126/sciadv.adj6979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 04/03/2024] [Indexed: 05/05/2024]
Abstract
Nature has devised many ways of producing males and females. Here, we report on a previously undescribed mechanism for Lepidoptera that functions without a female-specific gene. The number of alleles or allele heterozygosity in a single Z-linked gene (BaMasc) is the primary sex-determining switch in Bicyclus anynana butterflies. Embryos carrying a single BaMasc allele develop into WZ (or Z0) females, those carrying two distinct alleles develop into ZZ males, while (ZZ) homozygotes initiate female development, have mismatched dosage compensation, and die as embryos. Consequently, selection against homozygotes has favored the evolution of spectacular allelic diversity: 205 different coding sequences of BaMasc were detected in a sample of 246 females. The structural similarity of a hypervariable region (HVR) in BaMasc to the HVR in Apis mellifera csd suggests molecular convergence between deeply diverged insect lineages. Our discovery of this primary switch highlights the fascinating diversity of sex-determining mechanisms and underlying evolutionary drivers.
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Affiliation(s)
- Arjen E. van’t Hof
- Department of Evolution, Ecology and Behaviour, University of Liverpool, Liverpool L69 7ZB, UK
- Biology Centre of the Czech Academy of Sciences, Institute of Entomology, 370 05 České Budějovice, Czech Republic
| | - Sam Whiteford
- Department of Evolution, Ecology and Behaviour, University of Liverpool, Liverpool L69 7ZB, UK
| | - Carl J. Yung
- Department of Evolution, Ecology and Behaviour, University of Liverpool, Liverpool L69 7ZB, UK
| | - Atsuo Yoshido
- Biology Centre of the Czech Academy of Sciences, Institute of Entomology, 370 05 České Budějovice, Czech Republic
| | - 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
| | - Maaike A. de Jong
- Netherlands eScience Center, Science Park 402, 1098 XH Amsterdam, Netherlands
| | - Kian-Long Tan
- Department of Biological Sciences, National University of Singapore, Singapore 117543, Singapore
| | - Dantong Zhu
- Department of Biological Sciences, National University of Singapore, Singapore 117543, Singapore
| | - Antónia Monteiro
- Department of Biological Sciences, National University of Singapore, Singapore 117543, Singapore
| | | | - František Marec
- Biology Centre of the Czech Academy of Sciences, Institute of Entomology, 370 05 České Budějovice, Czech Republic
| | - Ilik J. Saccheri
- Department of Evolution, Ecology and Behaviour, University of Liverpool, Liverpool L69 7ZB, UK
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Li X, Liu H, Bi H, Wang Y, Xu J, Zhang S, Zhang Z, Zhang Z, Huang Y. Masculinizer gene controls sexual differentiation in Hyphantria cunea. INSECT SCIENCE 2024; 31:405-416. [PMID: 37464965 DOI: 10.1111/1744-7917.13247] [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: 02/21/2023] [Revised: 06/05/2023] [Accepted: 06/07/2023] [Indexed: 07/20/2023]
Abstract
The Masculinizer gene, Masc, encodes a lepidopteran-specific novel CCCH-type zinc finger protein, which controls sex determination and dosage compensation in Bombyx mori. Considering the potential application of it in pest control, it is necessary to investigate the function of Masc gene in Hyphantria cunea, a globally invasive forest pest. In the present study, we identified and functionally characterized the Masc gene, HcMasc, in H. cunea. Sequence analysis revealed that HcMASC contained the conserved CCCH-type zinc finger domain, nuclear localization signal, and male determining domain, in which the last was confirmed to be required for its masculinization in BmN cell line. However, expression data showed that unlike male-biased expression in B. mori, HcMasc gene expresses in main all developmental stages or tissues in both sexes. Clustered regularly interspaced palindromic repeats (CRISPR) / CRISPR-associated protein 9-based disruption of the common exons 1 and 3 of the HcMasc gene resulted in imbalanced sex ratio and abnormal external genitalia of both sexes. Our results suggest that the HcMasc gene is required for both male and female sexual differentiation and dosage compensation in H. cunea and provide a foundation for developing better strategies to control this pest.
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Affiliation(s)
- Xiaowei Li
- Laboratory of Evolutionary and Functional Genomics, School of Life Sciences, Chongqing University, Chongqing, China
- CAS Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai, China
| | - Huihui Liu
- Key Laboratory of Forest Protection, Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, State Forestry Administration, Beijing, China
| | - Honglun Bi
- CAS Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai, China
| | - Yaohui Wang
- CAS Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai, China
| | - Jun Xu
- CAS Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai, China
| | - Sufang Zhang
- Key Laboratory of Forest Protection, Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, State Forestry Administration, Beijing, China
| | - Zhen Zhang
- Key Laboratory of Forest Protection, Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, State Forestry Administration, Beijing, China
| | - Ze Zhang
- Laboratory of Evolutionary and Functional Genomics, School of Life Sciences, Chongqing University, Chongqing, China
| | - Yongping Huang
- CAS Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai, China
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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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Identification and Characterization of the Masculinizing Function of the Helicoverpa armigera Masc Gene. Int J Mol Sci 2021; 22:ijms22168650. [PMID: 34445352 PMCID: PMC8395511 DOI: 10.3390/ijms22168650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 08/08/2021] [Accepted: 08/09/2021] [Indexed: 11/17/2022] Open
Abstract
The Masculinizer (Masc) gene has been known to control sex development and dosage compensation in lepidopterans. However, it remains unclear whether its ortholog exists and plays the same roles in distantly related lepidopterans such as Helicoverpa armigera. To address this question, we cloned Masc from H. armigera (HaMasc), which contains all essential functional domains of BmMasc, albeit with less than 30% amino acid sequence identity with BmMasc. Genomic PCR and qPCR analyses showed that HaMasc is a Z chromosome-linked gene since its genomic content in males (ZZ) was two times greater than that in females (ZW). RT-PCR and RT-qPCR analyses revealed that HaMasc expression was sex- and stage-biased, with significantly more transcripts in males and eggs than in females and other stages. Transfection of a mixture of three siRNAs of HaMasc into a male embryonic cell line of H. armigera led to the appearance of female-specific mRNA splicing isoforms of H. armigeradoublesex (Hadsx), a downstream target gene of HaMasc in the H. armigera sex determination pathway. The knockdown of HaMasc, starting from the third instar larvae resulted in a shift of Hadsx splicing from male to female isoforms, smaller male pupa and testes, fewer but larger/longer spermatocytes and sperm bundles, delayed pupation and internal fusion of the testes and follicles. These data demonstrate that HaMasc functions as a masculinizing gene in the H. armigera sex-determination cascade.
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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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Hirota K, Matsuda-Imai N, Kiuchi T, Katsuma S. Characterization of nuclear localization signal in Ostrinia furnacalis Masculinizer protein. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2021; 106:e21768. [PMID: 33644912 DOI: 10.1002/arch.21768] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Revised: 12/29/2020] [Accepted: 01/11/2021] [Indexed: 06/12/2023]
Abstract
Bombyx mori Masculinizer protein (BmMasc) is essential for both masculinization and dosage compensation in B. mori. We previously identified a bipartite nuclear localization signal (NLS) of BmMasc and two essential residues (lysine at 274 [K274] and arginine at 275 [R275]) implicated in its function. Sequence comparison showed the presence of putative NLSs in lepidopteran Masc proteins, but their functional properties and critical residues are unknown. Here we characterized a putative NLS of Ostrinia furnacalis Masc (OfMasc) using B. mori ovary-derived BmN-4 cell line. Deletion and alanine scanning mutagenesis revealed that a putative NLS is required for nuclear localization of OfMasc. However, mutations at both K227 and R228, which correspond to K274 and R275 of BmMasc, respectively, do not greatly abolish the NLS activity. Additional mutagenesis analysis revealed that triple mutations at K227, R228, and K240 almost completely inhibited OfMasc nuclear localization. These results suggest that lepidopteran Masc proteins possess a common functional NLS, but the critical residues for its activity are different. Moreover, we examined the masculinizing activity of OfMasc derivatives and found that nuclear localization is not required for the masculinizing activity of OfMasc. The results from our studies indicate that lepidopteran Masc proteins function in the cytoplasm to drive masculinizing cascade.
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Affiliation(s)
- Kanako Hirota
- Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Noriko Matsuda-Imai
- Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Takashi Kiuchi
- Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Susumu Katsuma
- Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
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Zheng ZZ, Sun X, Zhang B, Pu J, Jiang ZY, Li M, Fan YJ, Xu YZ. Alternative splicing regulation of doublesex gene by RNA-binding proteins in the silkworm Bombyx mori. RNA Biol 2019; 16:809-820. [PMID: 30836863 DOI: 10.1080/15476286.2019.1590177] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Doublesex is highly conserved and sex-specifically spliced in insect sex-determination pathways, and its alternative splicing (AS) is regulated by Transformer, an exonic splicing activator, in the model system of Drosophila melanogaster. However, due to the lack of a transformer gene, AS regulation of doublesex remains unclear in Lepidoptera, which contain the economically important silkworm Bombyx mori and thousands of agricultural pests. Here, we use yeast three-hybrid system to screen for RNA-binding proteins that recognize sex-specific exons 3 and 4 of silkworm doublesex (Bm-dsx); this approach identified BxRBP1/Lark binding to the exon 3, and BxRBP2/TBPH and BxRBP3/Aret binding to the exon 4. Investigation of tissues shows that BxRBP1 and BxRBP2 have no sex specificity, but BxRBP3 has - three of its four isoforms are expressed with a sex-bias. Using novel sex-specific silkworm cell lines, we find that BxRBP1 and BxRBP3 directly interact with each other, and cooperatively function as splicing repressors. Over-expression of BxRBP1 and BxRBP3 isoforms efficiently inhibits splicing of the exons 3 and 4 in the female-specific cells and generates the male-specific isoform of Bm-dsx. We also demonstrate that the sex-determination upstream gene Masc regulates alternatively transcribed BxRBP3 isoforms. Thus, we identify a new regulatory mechanism of doublesex AS in the silkworm, revealing an evolutionary divergence in insect sex-determination.
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Affiliation(s)
- Zeng-Zhang Zheng
- a Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Science , Institute of Plant Physiology and Ecology, Chinese Academy of Sciences , Shanghai , China
| | - Xia Sun
- b College of Life Technology , Jiangsu University of Science and Technology , Zhenjiang , China
| | - Bei Zhang
- a Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Science , Institute of Plant Physiology and Ecology, Chinese Academy of Sciences , Shanghai , China
| | - Jia Pu
- a Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Science , Institute of Plant Physiology and Ecology, Chinese Academy of Sciences , Shanghai , China
| | - Ze-Yu Jiang
- a Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Science , Institute of Plant Physiology and Ecology, Chinese Academy of Sciences , Shanghai , China
| | - Muwang Li
- b College of Life Technology , Jiangsu University of Science and Technology , Zhenjiang , China
| | - Yu-Jie Fan
- c College of Life Science , Wuhan University , Wuhan , China
| | - Yong-Zhen Xu
- c College of Life Science , Wuhan University , Wuhan , China
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Kiuchi T, Sugano Y, Shimada T, Katsuma S. Two CCCH-type zinc finger domains in the Masc protein are dispensable for masculinization and dosage compensation in Bombyx mori. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2019; 104:30-38. [PMID: 30529581 DOI: 10.1016/j.ibmb.2018.12.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 12/04/2018] [Accepted: 12/06/2018] [Indexed: 06/09/2023]
Abstract
The Masculinizer (Masc) gene encodes a novel lepidopteran-specific protein that controls both masculinization and dosage compensation in the silkworm Bombyx mori. The Masc protein possesses two CCCH-type zinc finger domains (ZFs), a nuclear localization signal, and an 11-amino-acid region that is highly conserved among lepidopteran insects. Using a cell-based assay system, we revealed that two cysteine residues localized in the conserved region, but not ZFs, are required for masculinization. In addition, nuclear localization of the Masc protein is not associated with masculinizing activity. Because dosage compensation is considered to occur in the nucleus, we inferred that the two ZFs play a role in the establishment of dosage compensation. To investigate this hypothesis at the organism level, we utilized the CRISPR/Cas9 system and established three B. mori strains whose Masc is partially deleted at different regions. The strain lacking the 210 C-terminal amino acids of the Masc protein showed male-specific embryonic lethality due to its low abundance and/or instability. The male embryos of this strain expressed the female-type splice variants of B. mori doublesex and did not express the male-type mRNA of B. mori IGF-II mRNA-binding protein. Furthermore, mRNA levels of Z-linked genes were abnormally enhanced only in male embryos. In contrast, the strain lacking both ZFs grew normally and did not show any defective phenotypes including sexual differentiation and the expression of Z-linked genes, demonstrating that the two CCCH-type ZFs, which are conserved in lepidopteran Masc homologs, are dispensable for masculinization and dosage compensation.
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Affiliation(s)
- Takashi Kiuchi
- Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo, 113-8657, Japan.
| | - Yudai Sugano
- Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Toru Shimada
- Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi 1-1-1, 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, Yayoi 1-1-1, Bunkyo-ku, Tokyo, 113-8657, Japan.
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In vivo masculinizing function of the Ostrinia furnacalis Masculinizer gene. Biochem Biophys Res Commun 2018; 503:1768-1772. [DOI: 10.1016/j.bbrc.2018.07.111] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 07/22/2018] [Indexed: 11/22/2022]
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KATSUMA S, KIUCHI T, KAWAMOTO M, FUJIMOTO T, SAHARA K. Unique sex determination system in the silkworm, Bombyx mori: current status and beyond. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2018; 94:205-216. [PMID: 29760316 PMCID: PMC6021594 DOI: 10.2183/pjab.94.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 02/19/2018] [Indexed: 06/02/2023]
Abstract
The silkworm Bombyx mori has been used for silk production for over 5,000 years. In addition to its contribution to sericulture, B. mori has played an important role in the field of genetics. Classical genetic studies revealed that a gene(s) with a strong feminizing activity is located on the W chromosome, but this W-linked feminizing gene, called Feminizer (Fem), had not been cloned despite more than 80 years of study. In 2014, we discovered that Fem is a precursor of a single W chromosome-derived PIWI-interacting RNA (piRNA). Fem-derived piRNA binds to PIWI protein, and this complex then cleaves the mRNA of the Z-linked Masculinizer (Masc) gene, which encodes a protein required for both masculinization and dosage compensation. These findings showed that the piRNA-mediated interaction between the two sex chromosomes is the primary signal for the sex determination cascade in B. mori. In this review, we summarize the history, current status, and perspective of studies on sex determination and related topics in B. mori.
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Affiliation(s)
- Susumu KATSUMA
- Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Takashi KIUCHI
- Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Munetaka KAWAMOTO
- Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Toshiaki FUJIMOTO
- Laboratory of Applied Entomology, Faculty of Agriculture, Iwate University, Iwate, Japan
| | - Ken SAHARA
- Laboratory of Applied Entomology, Faculty of Agriculture, Iwate University, Iwate, Japan
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