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Lee J, Fujimoto T, Yamaguchi K, Shigenobu S, Sahara K, Toyoda A, Shimada T. W chromosome sequences of two bombycid moths provide an insight into the origin of Fem. Mol Ecol 2024; 33:e17434. [PMID: 38867501 DOI: 10.1111/mec.17434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 05/24/2024] [Accepted: 05/31/2024] [Indexed: 06/14/2024]
Abstract
Fem is a W-linked gene that encodes a piRNA precursor, and its product, Fem piRNA, is a master factor of female determination in Bombyx mori. Fem has low similarity to any known sequences, and the origin of Fem remains unclear. So far, two hypotheses have been proposed for the origin of Fem: The first hypothesis is that Fem is an allele of Masc, which assumes that the W chromosome was originally a homologous chromosome of the Z chromosome. The second hypothesis is that Fem arose by the transposition of Masc to the W chromosome. To explore the origin of Fem, we determined the W chromosome sequences of B. mori and, as a comparison, a closely relative bombycid species of Trilocha varians with a Fem-independent sex determination system. To our surprise, although the sequences of W and Z chromosomes show no homology to each other, a few pairs of homologues are shared by W and Z chromosomes, indicating the W chromosome of both species originated from Z chromosome. In addition, the W chromosome of T. varians lacks Fem, while the W chromosome of B. mori has over 100 copies of Fem. The high-quality assembly of the W chromosome of B. mori arose the third hypothesis about the origin of Fem: Fem is a chimeric sequence of multiple transposons. More than half of one transcriptional unit of Fem shows a significant homology to RTE-BovB. Moreover, the Fem piRNA-producing region could correspond to the boundary of the two transposons, gypsy and satellite DNA.
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Affiliation(s)
- Jung Lee
- Department of Life Science, Faculty of Science, Gakushuin University, Tokyo, Japan
| | - Toshiaki Fujimoto
- Laboratory of Applied Entomology, Faculty of Agriculture, Iwate University, Morioka, Japan
| | - Katsushi Yamaguchi
- Trans-Omics Facility, National Institute for Basic Biology, Okazaki, Japan
| | - Shuji Shigenobu
- Trans-Omics Facility, National Institute for Basic Biology, Okazaki, Japan
| | - Ken Sahara
- Laboratory of Applied Entomology, Faculty of Agriculture, Iwate University, Morioka, Japan
| | - Atsushi Toyoda
- Comparative Genomics Laboratory, Advanced Genomics Center, National Institute of Genetics, Shizuoka, Japan
| | - Toru Shimada
- Department of Life Science, Faculty of Science, Gakushuin University, Tokyo, Japan
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Qian Q, Xu D, Liao W, Zhuo Z. Predicting the current and future suitable distribution range of Trilocha varians (Walker, 1855) (Lepidoptera: Bombycidae) in China. BULLETIN OF ENTOMOLOGICAL RESEARCH 2024:1-10. [PMID: 38699862 DOI: 10.1017/s0007485324000117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2024]
Abstract
Trilocha varians is one of the major pests of Ficus spp. Based on 19 bioclimatic variables provided by the Worldclim, our study analysed the suitable distribution areas of T. varians under current and future climate changes (SSP1-2.6, SSP2-4.5, SSP5-8.5) for two periods (the 2050s and 2090s) using the maximum entropy algorithm (MaxEnt) model. Key environmental variables affecting the geographic distribution of T. varians were also identified, and the changes in the area of suitable range under current and future climate changes were compared. The results showed that the key environmental variables affecting the distribution of T. varians were temperature and precipitation, comprising annual mean temperature (bio1), temperature seasonality (standard deviation × 100) (bio4), precipitation of driest month (bio14), and precipitation of driest quarter (bio17). Under the current climatic conditions, the suitable distribution area of T. varians is within the range of 92°13'E-122°08'E, 18°17'N-31°55'N. The current high, medium, and low suitable areas for T. varians predicted by the MaxEnt model are 14.00 × 104, 21.50 × 104, and 71.95 × 104 km2, of which the high suitable areas are mainly distributed in southern Guangdong, southwestern Guangxi, western Taiwan, Hong Kong, and Hainan. Under different future climatic conditions, some of the high, medium, and low suitability zones for T. varians increased and some decreased, but the mass centre did not migrate significantly. The Pearl River Basin is predicted to remain the main distribution area of T. varians.
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Affiliation(s)
- Qianqian Qian
- College of Life Science, China West Normal University, Nanchong 637002, China
| | - Danping Xu
- College of Life Science, China West Normal University, Nanchong 637002, China
| | - Wenkai Liao
- College of Life Science, China West Normal University, Nanchong 637002, China
| | - Zhihang Zhuo
- College of Life Science, China West Normal University, Nanchong 637002, China
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Fujii T, Kodama S, Ishikawa Y, Yamamoto M, Sakurai T, Fónagy A. Lipid droplets in the pheromone glands of bombycids: Effects of larval diet on their size and pheromone titer. JOURNAL OF INSECT PHYSIOLOGY 2022; 142:104440. [PMID: 36084745 DOI: 10.1016/j.jinsphys.2022.104440] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 08/11/2022] [Accepted: 09/02/2022] [Indexed: 06/15/2023]
Abstract
In addition to the blend ratio, the quantity of sex pheromone components secreted by female moths may affect the efficient attraction of conspecific males. The present study using the silkmoth Bombyx mori, which has bombykol as its pheromone component, demonstrated that pheromone titer, body weight, and lipid droplet (LD) diameter in the pheromone gland were affected by the larval diet. Although the artificial diet contained approximately 11-fold more total fatty acids than mulberry leaf, the pheromone titer in the group fed the artificial diet (group AD) was approximately 2-fold higher than that of the group fed mulberry (group M). The diameter of LDs, which store the pheromone-precursor fatty acyl, E10,Z12-16:Acyl, was also larger in the AD group. The relatively small increase in sex pheromone titer by feeding on a fatty-acid-rich diet may be partly attributable to the storage of excess precursors in the LDs. We detected LDs in the pheromone glands of Trilocha varians, the closest non-congener of B. mori available in Bombycidae. T. varians uses bombykal and bombykyl acetate as sex pheromone components, which are biosynthesized via the same precursor fatty acyl as that of B. mori. The presence of LDs in T. varians suggests that the storage and mobilization mechanisms of the pheromone precursor fatty acyl via LDs may be conserved in bombycids.
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Affiliation(s)
- Takeshi Fujii
- Faculty of Agriculture, Setsunan University, 45-1 Nagao-Togecho, Hirakata, Osaka 573-0101, Japan.
| | - Sayo Kodama
- Faculty of Agriculture, Setsunan University, 45-1 Nagao-Togecho, Hirakata, Osaka 573-0101, Japan
| | - Yukio Ishikawa
- Faculty of Agriculture, Setsunan University, 45-1 Nagao-Togecho, Hirakata, Osaka 573-0101, Japan
| | - Masanobu Yamamoto
- Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Takeshi Sakurai
- Faculty of Agriculture, Tokyo University of Agriculture, Atsugi, Kanagawa 243-0034, Japan
| | - Adrien Fónagy
- Zoology Department, Plant Protection Institute, Centre for Agricultural Research, Eötvös Lóránd Research Network (formerly affiliated to the Hungarian Academy of Sciences), Budapest 1022, Hungary
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Kawamoto M, Kiuchi T, Katsuma S. SilkBase: an integrated transcriptomic and genomic database for Bombyx mori and related species. Database (Oxford) 2022; 2022:6603636. [PMID: 35670730 PMCID: PMC9216573 DOI: 10.1093/database/baac040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 04/21/2022] [Accepted: 05/21/2022] [Indexed: 11/13/2022]
Abstract
We introduce SilkBase as an integrated database for transcriptomic and genomic resources of the domesticated silkworm Bombyx mori and related species. SilkBase is the oldest B. mori database that was originally established as the expressed sequence tag database since 1999. Here, we upgraded the database by including the datasets of the newly assembled B. mori complete genome sequence, predicted gene models, bacterial artificial chromosome (BAC)-end and fosmid-end sequences, complementary DNA (cDNA) reads from 69 libraries, RNA-seq data from 10 libraries, PIWI-interacting RNAs (piRNAs) from 13 libraries, ChIP-seq data of 9 histone modifications and HP1 proteins and transcriptome and/or genome data of four B. mori-related species, i.e. Bombyx mandarina, Trilocha varians, Ernolatia moorei and Samia ricini. Our new integrated genome browser easily provides a snapshot of tissue- and stage-specific gene expression, alternative splicing, production of piRNAs and histone modifications at the gene locus of interest. Moreover, SilkBase is useful for performing comparative studies among five closely related lepidopteran insects. Database URL: https://silkbase.ab.a.u-tokyo.ac.jp
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Affiliation(s)
- Munetaka Kawamoto
- 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.,Infinity Matrix, Shiohama, Koto-ku, Tokyo 135-0043, Japan
| | - 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
| | - 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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Basari N, Mustafa NS, Yusrihan NEN, Yean CW, Ibrahim Z. The Effect of Temperature on the Development of Trilocha varians (Lepidoptera: Bombycidae) and Control of the Ficus Plant Pest. Trop Life Sci Res 2019; 30:23-31. [PMID: 30847031 PMCID: PMC6396895 DOI: 10.21315/tlsr2019.30.1.2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Ficus plants are commonly planted as ornamentals along roadsides in Malaysia. In 2010, Ficus plants in Kuala Terengganu were found to be attacked by a moth, identified as Trilocha varians. The larvae of this moth fed on Ficus leaves causing up to 100% defoliation. This study was conducted to determine the life cycle of T. varians under two different environmental temperatures and to control this pest using two different insecticides. Our findings showed that there were significant differences in the time taken for eggs to hatch and larval and pupation period between low and high environmental temperatures. Results also showed that fipronil had lower LT50 and LT95 than malathion. This study provides new information on the life history of T. varians under two different conditions and the efficiency in controlling T. varians larvae using insecticides. The results of this study are important for future management in controlling T. varians population especially in Kuala Terengganu, Malaysia.
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Affiliation(s)
- Norasmah Basari
- School of Marine and Environmental Sciences, Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia
| | - Nurul Salsabila Mustafa
- School of Marine and Environmental Sciences, Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia
| | - Nur Elya Nabila Yusrihan
- School of Marine and Environmental Sciences, Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia
| | - Chin Wei Yean
- School of Marine and Environmental Sciences, Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia
| | - Zainal Ibrahim
- Majlis Bandaraya Kuala Terengganu, Menara Permint, Jalan Sultan Ismail, 21000 Kuala Terengganu, Terengganu, Malaysia
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Lin RJ, Braby MF, Hsu YF. The Immature Stages, Biology, and Phylogenetic Relationships of Rotunda rotundapex (Lepidoptera: Bombycidae). JOURNAL OF INSECT SCIENCE (ONLINE) 2019; 19:5430260. [PMID: 30953584 PMCID: PMC6451653 DOI: 10.1093/jisesa/iez025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Indexed: 05/07/2023]
Abstract
The life history, morphology, and biology of the immature stages and phylogenetic relationships of Rotunda rotundapex (Miyata & Kishida, 1990) are described and illustrated for the first time. The species is univoltine: eggs hatch in spring (March or April) and the life cycle from egg to adult is completed in about 3 wk, with larvae developing rapidly on young leaves of the host plants, Morus australis and to a lesser extent Broussonetia monoica (Moraceae), and adults emerging in April-May. Eggs are laid in clusters on twigs of the host plant, are covered by scales during female oviposition, and remain in diapause for the remainder of the year (i.e., for 10-11 mo). Larvae (all instars) are unique among the Bombycidae in that they lack a horn on abdominal segment 8. A strongly supported molecular phylogeny based on six genes (5.0 Kbp: COI, EF-1α, RpS5, CAD, GAPDH, and wgl) representing seven genera of Bombycinae from the Old World revealed that Rotunda is a distinct monotypic lineage sister to Bombyx. This phylogenetic position, together with morphological data of the immature stages (egg and larval chaetotaxy), supports the current systematic classification in which the species rotundapex has been placed in a separate genus (Rotunda) from Bombyx in which it was previously classified.
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Affiliation(s)
- Rung-Juen Lin
- Department of Life Science, National Taiwan Normal University, Taipei, Taiwan
| | - Michael F Braby
- Division of Ecology and Evolution, Research School of Biology, The Australian National University, Acton, ACT, Australia
- The Australian National Insect Collection, National Research Collections Australia, Canberra, ACT, Australia
| | - Yu-Feng Hsu
- Department of Life Science, National Taiwan Normal University, Taipei, Taiwan
- Corresponding author, e-mail:
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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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Fujii T, Yamamoto M, Nakano R, Nirazawa T, Rong Y, Dong SL, Ishikawa Y. Alkenyl sex pheromone analogs in the hemolymph of an arctiid Eilema japonica and several non-arctiid moths. JOURNAL OF INSECT PHYSIOLOGY 2015; 82:109-113. [PMID: 26429763 DOI: 10.1016/j.jinsphys.2015.09.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 08/31/2015] [Accepted: 09/25/2015] [Indexed: 06/05/2023]
Abstract
The majority of moth species utilize compounds derived from de novo synthesized fatty acids as their sex pheromones (type I). In contrast, species belonging to two recently diverged moth families, Arctiidae and Geometridae, utilize alkenes and their epoxides, which are derived from dietary essential fatty acids (EFAs), as their sex pheromones (type II). In the latter species, EFAs are considered to be converted into alkenes, often after chain elongation, in specialized cells called oenocytes. These alkenes are transported through the hemolymph to the pheromone gland, from which they are secreted with or without further modifications. We confirmed that the appearance of EFA-derived alkenes in the hemolymph was closely associated with the completion of pheromone gland formation in an arctiid moth Eilema japonica. Analyses of the hemolymph of several moth species utilizing type-I sex pheromones demonstrated the occurrence of (Z,Z,Z)-3,6,9-tricosatriene (T23), a typical type-II component, in the hemolymph of a noctuid Mamestra brassicae and two crambids Ostrinia furnacalis and Ostrinia scapulalis. Our results demonstrated that moths utilizing type-I pheromones have the ability to synthesize type-II sex pheromones, and suggested that recently diverged groups of moths may have secondarily exploited EFA-derived alkenes as sex pheromones.
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Affiliation(s)
- Takeshi Fujii
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan.
| | - Masanobu Yamamoto
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan
| | - Ryo Nakano
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan
| | - Takuya Nirazawa
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan
| | - Yu Rong
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan
| | - Shuang-Lin Dong
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - Yukio Ishikawa
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan
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Lee J, Kiuchi T, Kawamoto M, Shimada T, Katsuma S. Identification and functional analysis of a Masculinizer orthologue in Trilocha varians (Lepidoptera: Bombycidae). INSECT MOLECULAR BIOLOGY 2015; 24:561-569. [PMID: 26154510 DOI: 10.1111/imb.12181] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We recently showed that the Masculinizer gene (Masc) plays a primary role in sex determination in the lepidopteran model insect Bombyx mori. However, it remains unknown whether this Masc protein-dependent sex determination system is conserved amongst lepidopteran insects or within the family Bombycidae. Here we cloned and characterized a Masc homologue (TvMasc) in Trilocha varians (Lepidoptera: Bombycidae), a species closely related to B. mori. To elucidate the role of TvMasc in the sex determination cascade of T. varians, TvMasc expression was knocked down in early embryos by the injection of small interfering RNAs (siRNAs) that targeted TvMasc mRNAs. Both female- and male-type splice variants of Tvdsx, a doublesex (dsx) homologue in T. varians were observed in control siRNA-injected embryos. By contrast, only female-type splice variants were observed in TvMasc siRNA-injected embryos. These results indicate that the TvMasc protein directly or indirectly regulates the splicing patterns of Tvdsx. Furthermore, we found that male-type splice variants of B. mori dsx (Bmdsx) were produced in TvMasc-overexpressing BmN4 cells. The mRNA level of B. mori Imp, a gene whose product induces male-specific Bmdsx splicing also increased. These results suggest that Masc genes play similar roles in the sex-determination cascade in Bombycidae.
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Affiliation(s)
- J Lee
- Department of Agricultural and Environmental Biology Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - T Kiuchi
- Department of Agricultural and Environmental Biology Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - M Kawamoto
- Department of Agricultural and Environmental Biology Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - T Shimada
- Department of Agricultural and Environmental Biology Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - S Katsuma
- Department of Agricultural and Environmental Biology Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
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Wang H, Kiuchi T, Katsuma S, Shimada T. A novel sucrose hydrolase from the bombycoid silkworms Bombyx mori, Trilocha varians, and Samia cynthia ricini with a substrate specificity for sucrose. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2015; 61:46-52. [PMID: 25937576 DOI: 10.1016/j.ibmb.2015.04.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Revised: 04/08/2015] [Accepted: 04/10/2015] [Indexed: 06/04/2023]
Abstract
Although membrane-associated sucrase activity has been detected in the midgut of various lepidopteran species, it has not yet been identified and characterized at the molecular level. In the present study, we identified a novel sucrose hydrolase (SUH) gene from the following three bombycoid silkworms: Bombyx mori, Trilocha varians, and Samia cynthia ricini and named them BmSuh, TvSuh, and ScSuh, respectively. The EST dataset showed that BmSuh is one of the major glycoside hydrolase genes in the larval midgut of B. mori. These genes were almost exclusively expressed in the larval midgut in all three species, mainly at the feeding stage. SUHs are classified into the glycoside hydrolase family 13 and show significant homology to insect maltases. Enzymatic assays revealed that recombinant SUHs were distinct from conventional maltases and exhibited substrate specificity for sucrose. The recombinant BmSUH was less sensitive to sugar-mimic alkaloids than TvSUH and ScSUH, which may explain the reason why the sucrase activity in the B. mori midgut was less affected by the sugar-mimic alkaloids derived from mulberry.
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Affiliation(s)
- Huabing Wang
- Laboratory of Insect Genetics and Bioscience, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo, Japan; College of Animal Sciences, Zhejiang University, China
| | - Takashi Kiuchi
- Laboratory of Insect Genetics and Bioscience, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo, Japan
| | - Susumu Katsuma
- Laboratory of Insect Genetics and Bioscience, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo, Japan
| | - Toru Shimada
- Laboratory of Insect Genetics and Bioscience, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo, Japan.
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Namiki S, Daimon T, Iwatsuki C, Shimada T, Kanzaki R. Antennal lobe organization and pheromone usage in bombycid moths. Biol Lett 2014; 10:20140096. [PMID: 24759369 DOI: 10.1098/rsbl.2014.0096] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We investigated the neuroanatomy of the macroglomerular complex (MGC), which is involved in sex pheromone processing, in five species in the subfamily Bombycinae, including Ernolatia moorei, Trilocha varians, Rondotia menciana, Bombyx mandarina and Bombyx mori. The glomerulus located at the dorsal-most part of the olfactory centre shows the largest volume in moth species examined to date. Such normal glomerular organization has been observed in E. moorei and T. varians, which use a two-component mixture and includes the compound bombykal as a mating signal. By contrast, the other three species, which use another component as a single attractant, exhibited a modified arrangement of the MGC. This correlation between pheromone usage and neural organization may be useful for understanding the process of speciation.
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Affiliation(s)
- Shigehiro Namiki
- Research Center for Advanced Science and Technology, The University of Tokyo, , Tokyo, Japan
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12
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Daimon T, Fujii T, Yago M, Hsu YF, Nakajima Y, Fujii T, Katsuma S, Ishikawa Y, Shimada T. Female sex pheromone and male behavioral responses of the bombycid moth Trilocha varians: comparison with those of the domesticated silkmoth Bombyx mori. Naturwissenschaften 2012; 99:207-15. [PMID: 22307535 DOI: 10.1007/s00114-012-0887-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Revised: 01/16/2012] [Accepted: 01/18/2012] [Indexed: 11/28/2022]
Abstract
Analysis of female sex pheromone components and subsequent field trap experiments demonstrated that the bombycid moth Trilocha varians uses a mixture of (E,Z)-10,12-hexadecadienal (bombykal) and (E,Z)-10,12-hexadecadienyl acetate (bombykyl acetate) as a sex pheromone. Both of these components are derivatives of (E,Z)-10,12-hexadecadienol (bombykol), the sex pheromone of the domesticated silkmoth Bombyx mori. This finding prompted us to compare the antennal and behavioral responses of T. varians and B. mori to bombykol, bombykal, and bombykyl acetate in detail. The antennae of T. varians males responded to bombykal and bombykyl acetate but not to bombykol, and males were attracted only when lures contained both bombykal and bombykyl acetate. In contrast, the antennae of B. mori males responded to all the three components. Behavioral analysis showed that B. mori males responded to neither bombykal nor bombykyl acetate. Meanwhile, the wing fluttering response of B. mori males to bombykol was strongly inhibited by bombykal and bombykyl acetate, thereby indicating that bombykal and bombykyl acetate act as behavioral antagonists for B. mori males. T. varians would serve as a reference species for B. mori in future investigations into the molecular mechanisms underlying the evolution of sex pheromone communication systems in bombycid moths.
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Affiliation(s)
- Takaaki Daimon
- 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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