The gonad develops as a testis in male or an ovary in female. In the silkworm, B. mori, little is known about testis and ovary in the embryonic stages and early larval stages. In this study, we performed morphological and histomorphological observations of ovaries and testes from the late embryonic stage to the 1st instar larval stage. Results obtained with lack of accurate information on sex of examined individuals may be misleading, thus we performed phenotypic observations of gonads by utilizing sex-limited strain that enables us to easily discriminate female embryos from male ones based on those egg colors. In testis, four testicular follicles were clearly observed in the testis at the first instar larval stage, and boundary layers were formed between the testicular follicles. At the late embryonic stage, the testis consisted of four testicular follicles, while the boundary layers were still obscure. In ovary, four ovarioles were easily recognizable in the ovary at the first instar larval stage, and boundary layers were formed between the ovarioles. However, in the late embryonic stage, it was quite difficult to identify four ovarioles. Morphological characteristics were almost similar between testis and ovary in early developmental stages. Our present study demonstrates that the most reliable difference between testis and ovary in early developmental stages is the attaching point of the duct. Formation and development of the duct may be sensitive to the sex-determining signal and display sexual dimorphism in early embryonic stages.
{"title":"Morphological and histomorphological structures of testes and ovaries in early developmental stages of the silkworm, <i>Bombyx mori</i>.","authors":"Hiroki Sakai, Yohei Kirino, Susumu Katsuma, Fugaku Aoki, Masataka G Suzuki","doi":"10.11416/jibs.85.1_015","DOIUrl":"https://doi.org/10.11416/jibs.85.1_015","url":null,"abstract":"<p><p>The gonad develops as a testis in male or an ovary in female. In the silkworm, <i>B. mori</i>, little is known about testis and ovary in the embryonic stages and early larval stages. In this study, we performed morphological and histomorphological observations of ovaries and testes from the late embryonic stage to the 1st instar larval stage. Results obtained with lack of accurate information on sex of examined individuals may be misleading, thus we performed phenotypic observations of gonads by utilizing sex-limited strain that enables us to easily discriminate female embryos from male ones based on those egg colors. In testis, four testicular follicles were clearly observed in the testis at the first instar larval stage, and boundary layers were formed between the testicular follicles. At the late embryonic stage, the testis consisted of four testicular follicles, while the boundary layers were still obscure. In ovary, four ovarioles were easily recognizable in the ovary at the first instar larval stage, and boundary layers were formed between the ovarioles. However, in the late embryonic stage, it was quite difficult to identify four ovarioles. Morphological characteristics were almost similar between testis and ovary in early developmental stages. Our present study demonstrates that the most reliable difference between testis and ovary in early developmental stages is the attaching point of the duct. Formation and development of the duct may be sensitive to the sex-determining signal and display sexual dimorphism in early embryonic stages.</p>","PeriodicalId":34896,"journal":{"name":"Journal of Insect Biotechnology and Sericology","volume":"85 1","pages":"15-20"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.11416/jibs.85.1_015","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"35541933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Y. Takemura, A. Ohnuma, Yuji Mochida, M. Mastumoto
{"title":"A simple method for homozygotic selection of Nd genes using artificial diet rearing in the silkworm, Bombyx mori","authors":"Y. Takemura, A. Ohnuma, Yuji Mochida, M. Mastumoto","doi":"10.11416/JIBS.85.1_001","DOIUrl":"https://doi.org/10.11416/JIBS.85.1_001","url":null,"abstract":"","PeriodicalId":34896,"journal":{"name":"Journal of Insect Biotechnology and Sericology","volume":"85 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63988191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rina Hamajima, C. Yasunaga–Aoki, M. Iwanaga, S. Imanishi, J. Kobayashi, Kuni Sasaki, T. Kusakabe, J. M. Lee, H. Mon, Michihiro Kobayashi, M. Ikeda
{"title":"rRNA degradation in Bombyx mori and Bombyx mandarina cells infected with heterologous nucleopolyhedroviruses","authors":"Rina Hamajima, C. Yasunaga–Aoki, M. Iwanaga, S. Imanishi, J. Kobayashi, Kuni Sasaki, T. Kusakabe, J. M. Lee, H. Mon, Michihiro Kobayashi, M. Ikeda","doi":"10.11416/JIBS.85.3_073","DOIUrl":"https://doi.org/10.11416/JIBS.85.3_073","url":null,"abstract":"","PeriodicalId":34896,"journal":{"name":"Journal of Insect Biotechnology and Sericology","volume":"85 1","pages":"73-77"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63988624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Hino, Daisuke Morokuma, H. Mon, J. M. Lee, T. Kusakabe
{"title":"Characterization of the roles of DNA polymerases, clamp, and clamp loaders during S-phase progression and cell cycle regulation in the silkworm, Bombyx mori","authors":"M. Hino, Daisuke Morokuma, H. Mon, J. M. Lee, T. Kusakabe","doi":"10.11416/JIBS.85.2_021","DOIUrl":"https://doi.org/10.11416/JIBS.85.2_021","url":null,"abstract":"","PeriodicalId":34896,"journal":{"name":"Journal of Insect Biotechnology and Sericology","volume":"85 1","pages":"21-29"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63987921","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Absence of hybrids between the domesticated silkmoth, Bombyx mori, and the wild mulberry silkmoth, B. mandarina, in natural populations around sericulture farms","authors":"N. Kômoto, Nobuo Kuwabara, K. Yukuhiro","doi":"10.11416/JIBS.85.3_067","DOIUrl":"https://doi.org/10.11416/JIBS.85.3_067","url":null,"abstract":"","PeriodicalId":34896,"journal":{"name":"Journal of Insect Biotechnology and Sericology","volume":"85 1","pages":"67-71"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63988799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Inhibitory effects on silk fibroin production by the expression of phenylalanyl-tRNA synthetase mutants in posterior silk glands of Bombyx mori","authors":"Hidetoshi Teramoto, K. Kojima","doi":"10.11416/JIBS.85.2_031","DOIUrl":"https://doi.org/10.11416/JIBS.85.2_031","url":null,"abstract":"","PeriodicalId":34896,"journal":{"name":"Journal of Insect Biotechnology and Sericology","volume":"85 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63988451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In the silkworm, Bombyx mori, femaleness is determined by the presence of the W chromosome irrespective of the number of Z chromosomes (Hashimoto, 1933). During meiosis in females, all chromosomes, including sex chromosomes, form bivalents (Traut et al., 1999). However, the W chromosome is recombinationally isolated from the Z chromosome in B. mori, because meiosis is achiasmatic, and no recombination occurs in females (Sahara et al., 2012). In sericulture, male silkworms are more viable and productive than female silkworms (Strunnikov, 1995). The sex-linked balanced lethal (SLBL) strains make it possible to rear only male silkworms, thus improving the production and quality of silk. The construction of an SLBL strain requires two steps: (i) induction of translocation events between the W and Z chromosomes and (ii) induction of Z-linked recessive lethal mutations, which are compensated by the dominant allele translocated onto the W chromosome (Strunnikov, 1995). In Japan, one such SLBL strain “PLATINA BOY,” has been introduced for commercial use in the production of luxury fabrics (Ohnuma, 2007, 2010). Generally, translocations and mutations are induced by irradiation or exposure to a chemical mutagen. However, Ohnuma has developed a strategy for obtaining T(W;Z) chromosomes and Z-linked recessive lethal mutations arising from frequent spontaneous translocation events between the T(W;Z)+ chromosome and T(Z;2)Y females (Fig. 1a, b) (Ohnuma, 2000; Ohnuma and Takemura, 2006; Ohnuma et al., 2009). He effectively used the sch gene and sex-linked recessive lethal mutations, and screened translocations and mutations soon after hatching (Fig. 1a, b). In all, 25 types of aberrant chromosomes were identified (Ohnuma, 2000; Ohnuma and Takemura, 2006; Ohnuma et al., 2009; Ohnuma, 2010). Unfortunately, most of them, except for T(Z;W)l4, T(Z;W)l7, T(W;Z;2)Y-3, and T(W;Z;2)Y-4, were discarded without any analysis. However, the remaining four aberrant sex chromosomes are novel bioresources and it is of great interest to determine whether the breakpoints of the spontaneous translocation events reside within the W-chromosomal region or Z-chromosomal region of the T(W;Z)+ chromosome. Genome data is powerful tool to characterize chromosomal aberrations. In the Bombyx genome project, most areas of the Bombyx genome were assembled into large blocks of sequences (International Silkworm Genome Consortium, 2008). However, the W chromosome sequences were not included in the genome data, because the male genome was subjected to a whole-genome shotgun analysis to avoid the repetitive nature of the W chromosome (Abe et al., 2005a; Sahara et al., 2003). On the other hand, twelve W-chromosome specific sequences have been identified by screening arbitrary 10-mer primers, which yielded female-specific amplification products (Abe et al., 2005b). These sequences have been used to characterize the structural mutants of the W chromosome (Abe et al., 2005b; 2008; Fujii et al., 2006;
在家蚕(Bombyx mori)中，雌性取决于W染色体的存在，而与Z染色体的数量无关(Hashimoto, 1933)。在雌性减数分裂期间，包括性染色体在内的所有染色体都形成二价体(Traut et al.， 1999)。然而，在家蚕中，W染色体是从Z染色体中重组分离出来的，因为减数分裂是单交叉的，在雌性中没有重组发生(Sahara et al, 2012)。在养蚕方面，雄蚕比雌蚕更有活力和生产力(Strunnikov, 1995)。通过性交平衡致死(SLBL)菌株，可以只培养雄蚕，从而提高蚕丝产量和质量。SLBL菌株的构建需要两个步骤:(i)诱导W和Z染色体之间的易位事件;(ii)诱导Z连锁的隐性致死突变，这些突变由易位到W染色体上的显性等位基因补偿(Strunnikov, 1995)。在日本，一种这样的SLBL菌株“PLATINA BOY”已被引入商业用途，用于生产奢侈面料(Ohnuma, 2007, 2010)。一般来说，易位和突变是由照射或暴露于化学诱变剂引起的。然而，Ohnuma已经开发出一种策略来获得T(W;Z)染色体和Z连锁隐性致死突变，这些突变是由T(W;Z)+染色体和T(Z;2)Y女性之间频繁的自发易位事件引起的(图1a, b) (Ohnuma, 2000;大沼和竹村，2006;Ohnuma et al.， 2009)。他有效地利用sch基因和性别连锁的隐性致死突变，并在孵化后不久筛选易位和突变(图1a, b)。总共鉴定出25种异常染色体(Ohnuma, 2000;大沼和竹村，2006;Ohnuma et al.， 2009;Ohnuma, 2010)。遗憾的是，除了T(Z;W) 14、T(Z;W) 17、T(W;Z;2)Y-3、T(W;Z;2)Y-4外，大部分都没有经过分析就被丢弃了。然而，剩余的4条异常性染色体是新的生物资源，确定自发性易位事件的断点是位于T(W;Z)+染色体的W染色体区域还是Z染色体区域是非常有趣的。基因组数据是表征染色体畸变的有力工具。在家蚕基因组计划中，家蚕基因组的大部分区域被组装成大的序列块(国际家蚕基因组联盟，2008年)。然而，W染色体序列并未包括在基因组数据中，因为为了避免W染色体的重复性，男性基因组进行了全基因组霰弹枪分析(Abe et al.， 2005a;撒哈拉等人，2003年)。另一方面，通过筛选任意10-mer引物，已经鉴定出12个w染色体特异性序列，这些引物产生了女性特异性扩增产物(Abe et al.， 2005b)。这些序列已被用来表征W染色体的结构突变(Abe等人，2005b;2008;Fujii等人，2006;2007)。在这项研究中，W特异性序列被用来表征由T(W;Z)+和T(Z;2)Y染色体之间自发易位引起的四个异常性染色体。我们获得了易位事件的断点位于T(W;Z)+染色体的W染色体区域的分子证据。我们还描述了W特异性序列在W染色体上的相对位置。
{"title":"Structural analysis of spontaneous Z-W translocations in the silkworm, Bombyx mori","authors":"T. Fujii, A. Ohnuma, Y. Banno, H. Abe","doi":"10.11416/JIBS.85.3_079","DOIUrl":"https://doi.org/10.11416/JIBS.85.3_079","url":null,"abstract":"In the silkworm, Bombyx mori, femaleness is determined by the presence of the W chromosome irrespective of the number of Z chromosomes (Hashimoto, 1933). During meiosis in females, all chromosomes, including sex chromosomes, form bivalents (Traut et al., 1999). However, the W chromosome is recombinationally isolated from the Z chromosome in B. mori, because meiosis is achiasmatic, and no recombination occurs in females (Sahara et al., 2012). In sericulture, male silkworms are more viable and productive than female silkworms (Strunnikov, 1995). The sex-linked balanced lethal (SLBL) strains make it possible to rear only male silkworms, thus improving the production and quality of silk. The construction of an SLBL strain requires two steps: (i) induction of translocation events between the W and Z chromosomes and (ii) induction of Z-linked recessive lethal mutations, which are compensated by the dominant allele translocated onto the W chromosome (Strunnikov, 1995). In Japan, one such SLBL strain “PLATINA BOY,” has been introduced for commercial use in the production of luxury fabrics (Ohnuma, 2007, 2010). Generally, translocations and mutations are induced by irradiation or exposure to a chemical mutagen. However, Ohnuma has developed a strategy for obtaining T(W;Z) chromosomes and Z-linked recessive lethal mutations arising from frequent spontaneous translocation events between the T(W;Z)+ chromosome and T(Z;2)Y females (Fig. 1a, b) (Ohnuma, 2000; Ohnuma and Takemura, 2006; Ohnuma et al., 2009). He effectively used the sch gene and sex-linked recessive lethal mutations, and screened translocations and mutations soon after hatching (Fig. 1a, b). In all, 25 types of aberrant chromosomes were identified (Ohnuma, 2000; Ohnuma and Takemura, 2006; Ohnuma et al., 2009; Ohnuma, 2010). Unfortunately, most of them, except for T(Z;W)l4, T(Z;W)l7, T(W;Z;2)Y-3, and T(W;Z;2)Y-4, were discarded without any analysis. However, the remaining four aberrant sex chromosomes are novel bioresources and it is of great interest to determine whether the breakpoints of the spontaneous translocation events reside within the W-chromosomal region or Z-chromosomal region of the T(W;Z)+ chromosome. Genome data is powerful tool to characterize chromosomal aberrations. In the Bombyx genome project, most areas of the Bombyx genome were assembled into large blocks of sequences (International Silkworm Genome Consortium, 2008). However, the W chromosome sequences were not included in the genome data, because the male genome was subjected to a whole-genome shotgun analysis to avoid the repetitive nature of the W chromosome (Abe et al., 2005a; Sahara et al., 2003). On the other hand, twelve W-chromosome specific sequences have been identified by screening arbitrary 10-mer primers, which yielded female-specific amplification products (Abe et al., 2005b). These sequences have been used to characterize the structural mutants of the W chromosome (Abe et al., 2005b; 2008; Fujii et al., 2006; ","PeriodicalId":34896,"journal":{"name":"Journal of Insect Biotechnology and Sericology","volume":"78 1","pages":"79-85"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63988723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Immune response in the hemocyte after phagocytosis influences the infection with Beauveria brongniartii to the silkworm, Bombyx mori","authors":"S. Wada, W. Mitsuhashi, K. Miyamoto, Y. Kunimi","doi":"10.11416/JIBS.85.3_055","DOIUrl":"https://doi.org/10.11416/JIBS.85.3_055","url":null,"abstract":"","PeriodicalId":34896,"journal":{"name":"Journal of Insect Biotechnology and Sericology","volume":"85 1","pages":"55-65"},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.11416/JIBS.85.3_055","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63988742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Daisuke Morokuma, H. Mon, Y. Banno, T. Kusakabe, J. M. Lee
{"title":"Differential N-Glycan Modifications of Human Alpha 1-Acid Glycoprotein (α1AGP) Produced in Different Silkworm Strains using the Baculovirus Expression System","authors":"Daisuke Morokuma, H. Mon, Y. Banno, T. Kusakabe, J. M. Lee","doi":"10.11416/JIBS.84.2_049","DOIUrl":"https://doi.org/10.11416/JIBS.84.2_049","url":null,"abstract":"","PeriodicalId":34896,"journal":{"name":"Journal of Insect Biotechnology and Sericology","volume":"84 1","pages":"49-53"},"PeriodicalIF":0.0,"publicationDate":"2015-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63988278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Aquaporins are expressed in the columnar cells of the midgut epithelium of the silkworm, Bombyx mori","authors":"Mariya Maruyama, M. Azuma","doi":"10.11416/JIBS.84.3_055","DOIUrl":"https://doi.org/10.11416/JIBS.84.3_055","url":null,"abstract":"","PeriodicalId":34896,"journal":{"name":"Journal of Insect Biotechnology and Sericology","volume":"84 1","pages":"55-61"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63987840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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