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Zhang Z, Liu X, Yu Y, Yang F, Li K. The receptor tyrosine kinase torso regulates ecdysone homeostasis to control developmental timing in Bombyx mori. Insect Sci 2021; 28:1582-1590. [PMID: 33205532 PMCID: PMC9291747 DOI: 10.1111/1744-7917.12879] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Revised: 09/11/2020] [Accepted: 09/24/2020] [Indexed: 06/11/2023]
Abstract
Insect growth and development are precisely controlled by hormone homeostasis. The prothoracicotropic hormone (PTTH) receptor, Torso, is a member of the receptor tyrosine kinase family in insects. Activation of Torso by PTTH triggers biosynthesis and release of the steroid hormone in the prothoracic gland (PG). Although numbers of genes functioning in steroid hormone synthesis and metabolism have been identified in insects, the PTTH transduction pathway via its receptor Torso is poorly understood. In the current study, we describe a loss-of-function analysis of Torso in the silkworm, Bombyx mori, by targeted gene disruption using the transgenic CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/RNA-guided Cas9 nucleases) system. Depletion of B. mori Torso (BmTorso) did not eventually affect larval ecdysis and metamorphosis processes. Instead, BmTorso deficiency resulted in significant extension of developing time during larval and pupal stages with increased pupa and cocoon sizes. The ecdysteriod titers in the hemolymph of BmTorso mutants sharpy declined. Transcriptional levels of genes involved in ecdysone biosynthesis and ecdysteroid signaling pathways were significantly reduced in BmTorso-deficient animals. Additionally, RNA-Seq analysis revealed that genes involved in the longevity pathway and protein processing in the endoplasmic reticulum pathway were affected after BmTorso deletion. These results indicate that Torso is critical for maintaining steroid hormone homeostasis in insects.
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Affiliation(s)
- Zhong‐Jie Zhang
- School of Life ScienceEast China Normal UniversityShanghai200062China
- Key Laboratory of Insect Developmental and Evolutionary BiologyCenter for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai200032China
- CAS Center for Excellence in Biotic InteractionsUniversity of Chinese Academy of SciencesBeijing100049China
| | - Xiao‐Jing Liu
- Key Laboratory of Insect Developmental and Evolutionary BiologyCenter for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai200032China
- CAS Center for Excellence in Biotic InteractionsUniversity of Chinese Academy of SciencesBeijing100049China
| | - Ye Yu
- Key Laboratory of Insect Developmental and Evolutionary BiologyCenter for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai200032China
- CAS Center for Excellence in Biotic InteractionsUniversity of Chinese Academy of SciencesBeijing100049China
| | - Fang‐Ying Yang
- Key Laboratory of Insect Developmental and Evolutionary BiologyCenter for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai200032China
- CAS Center for Excellence in Biotic InteractionsUniversity of Chinese Academy of SciencesBeijing100049China
| | - Kai Li
- School of Life ScienceEast China Normal UniversityShanghai200062China
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2
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Luo JW, An EX, Lu YR, Yang L, Gai TT, He SZ, Wu SY, Hu H, Li CL, Lu C, Tong XL, Dai FY. Molecular basis of the silkworm mutant re l causing red egg color and embryonic death. Insect Sci 2021; 28:1290-1299. [PMID: 32918398 DOI: 10.1111/1744-7917.12871] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 08/26/2020] [Accepted: 09/01/2020] [Indexed: 06/11/2023]
Abstract
The coloration and hatchability of insect eggs can affect individual and population survival. However, few genetic loci have been documented to affect both traits, and the genes involved in regulating these two traits are unclear. The silkworm recessive mutant rel shows both red egg color and embryo mortality. We studied the molecular basis of the rel phenotype formation. Through genetic analysis, gene screening and sequencing, we found that two closely linked genes, BGIBMGA003497 (Bm-re) and BGIBMGA003697 (BmSema1a), control egg color and embryo mortality, respectively. Six base pairs of the Bm-re gene are deleted in its open reading frame, and BmSema1a is expressed at abnormally low levels in mutant rel . BmSema1a gene function verification was performed using RNA interference and clustered randomly interspersed palindromic repeats (CRISPR)/CRISPR-associate protein 9. Deficiency of the BmSema1a gene can cause the death of silkworm embryos. This study revealed the molecular basis of silkworm rel mutant formation and indicated that the Sema1a gene is essential for insect embryo development.
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Affiliation(s)
- Jiang-Wen Luo
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, College of Biotechnology, Southwest University, Chongqing, 400715, China
| | - Er-Xia An
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, College of Biotechnology, Southwest University, Chongqing, 400715, China
| | - Ya-Ru Lu
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, College of Biotechnology, Southwest University, Chongqing, 400715, China
| | - Ling Yang
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, College of Biotechnology, Southwest University, Chongqing, 400715, China
| | - Ting-Ting Gai
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, College of Biotechnology, Southwest University, Chongqing, 400715, China
| | - Song-Zhen He
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, College of Biotechnology, Southwest University, Chongqing, 400715, China
| | - Song-Yuan Wu
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, College of Biotechnology, Southwest University, Chongqing, 400715, China
| | - Hai Hu
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, College of Biotechnology, Southwest University, Chongqing, 400715, China
| | - Chun-Lin Li
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, College of Biotechnology, Southwest University, Chongqing, 400715, China
| | - Cheng Lu
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, College of Biotechnology, Southwest University, Chongqing, 400715, China
| | - Xiao-Ling Tong
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, College of Biotechnology, Southwest University, Chongqing, 400715, China
| | - Fang-Yin Dai
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, College of Biotechnology, Southwest University, Chongqing, 400715, China
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3
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Lyu H, Xu G, Peng X, Gong C, Peng Y, Song Q, Feng Q, Zheng S. Interacting C/EBPg and YBP regulate DNA methyltransferase 1 expression in Bombyx mori embryos and ovaries. Insect Biochem Mol Biol 2021; 134:103583. [PMID: 34010702 DOI: 10.1016/j.ibmb.2021.103583] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 04/05/2021] [Accepted: 04/20/2021] [Indexed: 06/12/2023]
Abstract
DNA methylation is an important epigenetic modification. DNA methyltransferases (Dnmts), which catalyze the formation of 5-methylcytosine, play a role in ovarian and embryonic development in some insects. However, the underlying mechanism of Dnmt in mediating ovarian and embryonic development remains unclear. In this study, the regulation and function of Bombyx mori Dnmt1 were investigated. By progressively deleting the sequence upstream of Dnmt1, a region located between -580 and -560 region from the transcription initiation site was found to have the most transcriptional activity. Electrophoretic mobility shift assay and chromatin immunoprecipitation demonstrated that transcription factor Y box binding protein (YBP), a homolog of human Y box binding protein 1 (YBX1), bound to the -580 to -560 region. YBP knockdown and overexpression in a Bombyx cell line indicated that YBP activates Dnmt1 expression. Furthermore, GST-pulldown and co-immunoprecipitation demonstrated that YBP and ovarian CCAAT/enhancer binding protein (C/EBPg) could bind each other. Simultaneous knockdown of C/EBPg and YBP was more effective than single-gene RNAi in inhibiting Dnmt1 expression and reducing the hatching rate. These results demonstrated that the interaction of C/EBPg and YBP activated Dnmt1 expression. Correlated with the expression profiles of the studies genes, our results suggest that high-level expression and interaction of C/EBPg and YBP in ovaries and embryos enhance the expression of Dnmt1, thus ensuring high reproduction rate in B. mori.
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Affiliation(s)
- Hao Lyu
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China; Guangzhou Key Laboratory of Insect Development Regulation and Applied Research, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Guanfeng Xu
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China; Guangzhou Key Laboratory of Insect Development Regulation and Applied Research, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Xuezhen Peng
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China; Guangzhou Key Laboratory of Insect Development Regulation and Applied Research, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Chengcheng Gong
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China; Guangzhou Key Laboratory of Insect Development Regulation and Applied Research, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Yuling Peng
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China; Guangzhou Key Laboratory of Insect Development Regulation and Applied Research, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Qisheng Song
- Division of Plant Sciences, College of Agriculture, Food and Natural Resources, University of Missouri, Columbia, MO, 65211, USA
| | - Qili Feng
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China; Guangzhou Key Laboratory of Insect Development Regulation and Applied Research, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Sichun Zheng
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China; Guangzhou Key Laboratory of Insect Development Regulation and Applied Research, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, 510631, China.
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4
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Gu SH, Chen CH, Lin PL. Expression of protein tyrosine phosphatases and Bombyx embryonic development. J Insect Physiol 2021; 130:104198. [PMID: 33549567 DOI: 10.1016/j.jinsphys.2021.104198] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 11/25/2020] [Accepted: 01/28/2021] [Indexed: 06/12/2023]
Abstract
Protein phosphorylation is an integral component of signal transduction pathways within eukaryotic cells, and it is regulated by coordinated interactions between protein kinases and protein phosphatases. Our previous study demonstrated differential expressions of serine/threonine protein phosphatases (PP2A and calcineurin) between diapause and developing eggs in Bombyx mori. In the present study, we further investigated expression of protein tyrosine phosphatases (PTPs) in relation to the Bombyx embryonic development. An immunoblot analysis showed that eggs contained the proteins of the 51-kDa PTP 1B (PTP1B), the 55-kDa phosphatase and tensin homologue (PTEN), and the 70-kDa Src homology 2 (SH2) domain-containing phosphatase 2 (SHP2), which undergo differential changes between diapause and developing eggs. Protein level of PTP1B and PTEN in eggs whose diapause initiation was prevented by HCl gradually increased toward embryonic development. The protein level of SHP2 also showed a dramatic increase on days 7 and 8 after HCl treatment. However, protein levels of PTP1B, PTEN, and SHP2 in diapause eggs remained at low levels during the first 9 days after oviposition. These differential changing patterns in protein levels were further confirmed using both non-diapause eggs and eggs in which diapause had been terminated by chilling of diapausing eggs at 5 °C for 70 days and then were transferred to 25 °C. Direct determination of PTP enzymatic activities showed higher activities in developing eggs (HCl-treated eggs, non-diapause eggs, and chilled eggs) compared to those in diapause eggs. Examination of temporal changes in mRNA expression levels of PTP1B, PTEN, and SHP2 did not show significant differences between diapause eggs and HCl-treated eggs except high expression in SHP2 variant B during the later embryonic development in HCl-treated eggs. These results demonstrate that higher protein levels of PTP1B, PTEN, and SHP2 and increased tyrosine phosphatase enzymatic activities in developing eggs are likely related to embryonic development of B. mori.
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Affiliation(s)
- Shi-Hong Gu
- Department of Biology, National Museum of Natural Science, 1 Kuan-Chien Road, Taichung 404, Taiwan, ROC.
| | - Chien-Hung Chen
- Chung Hwa University of Medical Technology, 89 Wen-Hwa 1st Road, Jen-Te Township, Tainan County 717, Taiwan, ROC
| | - Pei-Ling Lin
- Department of Biology, National Museum of Natural Science, 1 Kuan-Chien Road, Taichung 404, Taiwan, ROC
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5
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Wu TF, Shi WY, Chiu YC, Chan YY. Investigation of the molecular mechanism underlying the inhibitory activities of ethanol extract of Bombyx mori pupa-incubated Cordyceps militaris fruiting bodies toward allergic rhinitis. Biomed Pharmacother 2021; 135:111248. [PMID: 33450505 DOI: 10.1016/j.biopha.2021.111248] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 12/22/2020] [Accepted: 01/03/2021] [Indexed: 12/30/2022] Open
Abstract
Cordyceps militaris has been widely studied for its various pharmacological activities such as antitumor, anti-inflammation, and immune regulation. The binding of an allergen to IgE-sensitized mast cells in nasal mucosa triggers allergic rhinitis. We found that oral administration of 300 mg/kg of the ethanol extract prepared from silkworm pupa-cultivated Cordyceps militaris fruiting bodies significantly alleviated the symptoms of ovalbumin-induced allergic rhinitis in mice, including sneeze/scratch, mast cell activation, eosinophil infiltration, and Syk activation. The treatment of ethanol extract significantly suppressed the release of β-hexosaminidase (a degranulation marker) and mRNA expression levels of various cytokines, including IL-3, IL-10, and IL-13 in activated RBL2H3 cells. The ethanol extract and β-sitostenone, which was purified from the extract, could respectively reduce the Ca2+ ion mobilization in activated RBL-2H3 cells. Furthermore, results collected from western immunoblotting demonstrated that ethanol extract significantly retarded Ca2+ ion mobilization-initiated signaling cascade, which provoked the expression of various allergic cytokines. Also, the extract incubation interfered with P38 as well as NF-kB activation and Nrf-2 translocation. Our study suggested that ethanol extract possessed some natural constituents which could inhibit immediate degranulation and de novo synthesis of allergic cytokines via inhibition of Ca2+ ion mobilization in mast cells in the nasal mucosa of allergic rhinitis mice.
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Affiliation(s)
- Ting-Feng Wu
- Department of Biotechnology and Food Technology, Southern Taiwan University of Science and Technology, Tainan 710, Taiwan.
| | - Wan-Yin Shi
- Department of Biotechnology and Food Technology, Southern Taiwan University of Science and Technology, Tainan 710, Taiwan.
| | - Yi-Chen Chiu
- Department of Biotechnology and Food Technology, Southern Taiwan University of Science and Technology, Tainan 710, Taiwan.
| | - Yu-Yi Chan
- Department of Biotechnology and Food Technology, Southern Taiwan University of Science and Technology, Tainan 710, Taiwan.
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6
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Tsuchiya R, Kaneshima A, Kobayashi M, Yamazaki M, Takasu Y, Sezutsu H, Tanaka Y, Mizoguchi A, Shiomi K. Maternal GABAergic and GnRH/corazonin pathway modulates egg diapause phenotype of the silkworm Bombyx mori. Proc Natl Acad Sci U S A 2021; 118:e2020028118. [PMID: 33443213 PMCID: PMC7817158 DOI: 10.1073/pnas.2020028118] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Diapause represents a major developmental switch in insects and is a seasonal adaptation that evolved as a specific subtype of dormancy in most insect species to ensure survival under unfavorable environmental conditions and synchronize populations. However, the hierarchical relationship of the molecular mechanisms involved in the perception of environmental signals to integration in morphological, physiological, behavioral, and reproductive responses remains unclear. In the bivoltine strain of the silkworm Bombyx mori, embryonic diapause is induced transgenerationally as a maternal effect. Progeny diapause is determined by the environmental temperature during embryonic development of the mother. Here, we show that the hierarchical pathway consists of a γ-aminobutyric acid (GABA)ergic and corazonin signaling system modulating progeny diapause induction via diapause hormone release, which may be finely tuned by the temperature-dependent expression of plasma membrane GABA transporter. Furthermore, this signaling pathway possesses similar features to the gonadotropin-releasing hormone (GnRH) signaling system for seasonal reproductive plasticity in vertebrates.
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Affiliation(s)
- Ryoma Tsuchiya
- Faculty of Textile Science and Technology, Shinshu University, Ueda 386-8567, Japan
| | - Aino Kaneshima
- Faculty of Textile Science and Technology, Shinshu University, Ueda 386-8567, Japan
| | - Masakazu Kobayashi
- Faculty of Textile Science and Technology, Shinshu University, Ueda 386-8567, Japan
| | - Maki Yamazaki
- Faculty of Textile Science and Technology, Shinshu University, Ueda 386-8567, Japan
| | - Yoko Takasu
- National Agriculture and Food Research Organization, 305-8634 Tsukuba, Japan
| | - Hideki Sezutsu
- National Agriculture and Food Research Organization, 305-8634 Tsukuba, Japan
| | - Yoshiaki Tanaka
- National Agriculture and Food Research Organization, 305-8634 Tsukuba, Japan
| | - Akira Mizoguchi
- Division of Liberal Arts and Sciences, Aichi Gakuin University, Nisshin 470-0195, Japan
| | - Kunihiro Shiomi
- Faculty of Textile Science and Technology, Shinshu University, Ueda 386-8567, Japan;
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7
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Fujinaga D, Gu J, Kawahara H, Ogihara MH, Kojima I, Takeshima M, Kataoka H. Twenty-hydroxyecdysone produced by dephosphorylation and ecdysteroidogenesis regulates early embryonic development in the silkmoth, Bombyx mori. Insect Biochem Mol Biol 2020; 127:103491. [PMID: 33096212 DOI: 10.1016/j.ibmb.2020.103491] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 10/17/2020] [Accepted: 10/17/2020] [Indexed: 06/11/2023]
Abstract
Ecdysteroids are key regulators of embryonic development as well as molting and metamorphosis in insects. Although an active form of ecdysteroids, 20-hydroxyecdysone (20E) is known to be produced through ecdysteroidogenesis from cholesterol and dephosphorylation of 20E-phosphate during embryogenesis in Lepidoptera, the importance of these production mechanisms in embryonic development has been unclear. Here, we investigated the activation timing of ecdysteroidogenesis from cholesterol and 20E-phosphate dephosphorylation during early embryogenesis in non-diapause eggs of the silkmoth Bombyx mori by observing morphological development, quantifying 20E and 20E-phosphate, measuring transcripts of enzymes involved in 20E production, and detecting activity of these enzymes using egg extracts. Stage-dependent 20E fluctuation and changes in mRNA amounts of enzymes suggest that the two 20E-producing mechanisms are activated at different stages during embryogenesis. Furthermore, knockdown of a dephosphorylation enzyme delayed development at early embryogenesis, whereas knockdown of an ecdysteroidogenic enzyme delayed development at early-middle embryogenesis. These results suggest that 20E is primarily produced initially by dephosphorylation of 20E-phosphate, and then by ecdysteroidogenesis from cholesterol to induce progression of embryonic development in B. mori.
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Affiliation(s)
- Daiki Fujinaga
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, 277-8562, Japan
| | - Junjie Gu
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, 277-8562, Japan
| | - Hajime Kawahara
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, 277-8562, Japan
| | - Mari H Ogihara
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, 277-8562, Japan
| | - Ikumi Kojima
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, 277-8562, Japan
| | - Mika Takeshima
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, 277-8562, Japan
| | - Hiroshi Kataoka
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, 277-8562, Japan.
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Chen A, Li Q, Liao P, Zhao Q, Tang S, Wang P, Meng G, Dong Z. Semaphorin-1a-like gene plays an important role in the embryonic development of silkworm, Bombyx mori. PLoS One 2020; 15:e0240193. [PMID: 33007004 PMCID: PMC7531805 DOI: 10.1371/journal.pone.0240193] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Accepted: 09/22/2020] [Indexed: 11/18/2022] Open
Abstract
Fuyin-lethal red egg (Fuyin-lre) is a red egg mutant discovered from the germplasm resource Fuyin of Bombyx mori. The embryo of Fuyin-lre stops developing at the late stage of gastrulation due to chromosome structural variation. In this work, precise mutation sites at both ends of the mutated region were determined, and two inserted sequences with lengths of 1232 bp and 1845 bp were obtained at both ends of the mutation region. Interestingly, a bmmar1 transposon was detected in the inserted 1845 bp sequence. Bmmar1 possesses features of the Tcl/mariner superfamily of transposable elements (TEs), which belongs to class II TEs that use a DNA-mediated "cut and paste" mechanism to transpose. This finding suggests that Fuyin-lre mutation might be related to the "cut and paste" action of bmmar1. The mutation resulted in the deletion of 9 genes in the mutation region, of which the red egg gene re (BMSK0002766) did not affect embryonic development of B. mori, and the BMSK0002765 gene was unexpressed during the early stage of embryonic development. The RNA interference results of the remaining 7 genes suggest that the semaphorin-1a-like gene (BMSK0002764) had a major contribution to the embryonic lethality of Fuyin-lre.
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Affiliation(s)
- Anli Chen
- The Sericultural and Apicultural Research Institute, Yunnan Academy of Agricultural Sciences, Mengzi Yunnan, China
- The Key Sericultural Laboratory of Shaanxi, Ankang University, Ankang Shaanxi, China
| | - Qiongyan Li
- The Sericultural and Apicultural Research Institute, Yunnan Academy of Agricultural Sciences, Mengzi Yunnan, China
| | - Pengfei Liao
- The Sericultural and Apicultural Research Institute, Yunnan Academy of Agricultural Sciences, Mengzi Yunnan, China
| | - Qiaoling Zhao
- The Sericultural Research Institute, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, China
| | - Shunming Tang
- The Sericultural Research Institute, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, China
| | - Pingyang Wang
- The Sericultural Research Institute, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, China
| | - Gang Meng
- The Sericultural Research Institute, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, China
| | - Zhanpeng Dong
- The Sericultural and Apicultural Research Institute, Yunnan Academy of Agricultural Sciences, Mengzi Yunnan, China
- * E-mail:
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9
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Long W, Wu J, Shen G, Zhang H, Liu H, Xu Y, Gu J, Jia L, Lin Y, Xia Q. Estrogen-related receptor participates in regulating glycolysis and influences embryonic development in silkworm Bombyx mori. Insect Mol Biol 2020; 29:160-169. [PMID: 31566836 DOI: 10.1111/imb.12619] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 08/04/2019] [Accepted: 09/03/2019] [Indexed: 06/10/2023]
Abstract
Estrogen-related receptors (ERRs) play indispensable roles in development, energy metabolism, and cancers and are metabolic switches in Drosophila. However, the mechanism underlying their metabolic role is unknown in insects. This study analysed the expression profiles of Bombyx mori ERR (BmERR), hexokinase (BmHK), pyruvate kinase (BmPK) and phosphofructokinase (BmPFK) during embryonic development. The expression of BmERR tended to be similar to that of the other genes. We observed a regulatory association between BmERR and glycolytic rate-limiting enzymes by BmERR overexpression, RNA interference (RNAi), and ERR inhibitors in B. mori embryo cells. Subsequently, ERR cis-regulation elements (ERREs) were predicted and identified in the BmPFK promoter. Transfection assays, electrophoretic mobility shift assays and chromatin immunoprecipitation showed that BmERR can bind to one of these elements to regulate the expression of BmPFK. ERREs were also predicted in the BmHK and BmPK promoters. In the eggs, the expression of glycolytic rate-limiting enzyme genes was suppressed when the expression of BmERR was interference by double-stranded BmERR, the glucose levels also was increased. Meanwhile, the development of silkworm embryos was delayed by about 1 day. These results indicate that BmERR can bind to the ERREs of glycolytic gene promoters and regulate the expression of glycolytic genes, ultimately affecting embryonic development in silkworms.
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Affiliation(s)
- W Long
- Biological Science Research Center Southwest University, Chongqing, China
- Chongqing Key Laboratory of Sericulture Science, Chongqing, China
| | - J Wu
- Biological Science Research Center Southwest University, Chongqing, China
- Chongqing Key Laboratory of Sericulture Science, Chongqing, China
| | - G Shen
- Biological Science Research Center Southwest University, Chongqing, China
- Chongqing Key Laboratory of Sericulture Science, Chongqing, China
- Chongqing Engineering and Technology Research Center for Novel Silk Materials, Chongqing, China
| | - H Zhang
- Biological Science Research Center Southwest University, Chongqing, China
- Chongqing Key Laboratory of Sericulture Science, Chongqing, China
| | - H Liu
- Biological Science Research Center Southwest University, Chongqing, China
- Chongqing Key Laboratory of Sericulture Science, Chongqing, China
| | - Y Xu
- Biological Science Research Center Southwest University, Chongqing, China
- Chongqing Key Laboratory of Sericulture Science, Chongqing, China
| | - J Gu
- Biological Science Research Center Southwest University, Chongqing, China
- Chongqing Key Laboratory of Sericulture Science, Chongqing, China
| | - L Jia
- Biological Science Research Center Southwest University, Chongqing, China
- Chongqing Key Laboratory of Sericulture Science, Chongqing, China
| | - Y Lin
- Biological Science Research Center Southwest University, Chongqing, China
- Chongqing Key Laboratory of Sericulture Science, Chongqing, China
- Chongqing Engineering and Technology Research Center for Novel Silk Materials, Chongqing, China
| | - Q Xia
- Biological Science Research Center Southwest University, Chongqing, China
- Chongqing Key Laboratory of Sericulture Science, Chongqing, China
- Chongqing Engineering and Technology Research Center for Novel Silk Materials, Chongqing, China
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10
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Li B, Hu P, Zhu LB, You LL, Cao HH, Wang J, Zhang SZ, Liu MH, Toufeeq S, Huang SJ, Xu JP. DNA Methylation Is Correlated with Gene Expression during Diapause Termination of Early Embryonic Development in the Silkworm ( Bombyx mori). Int J Mol Sci 2020; 21:E671. [PMID: 31968548 PMCID: PMC7013401 DOI: 10.3390/ijms21020671] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Revised: 01/16/2020] [Accepted: 01/16/2020] [Indexed: 12/13/2022] Open
Abstract
DNA modification is a naturally occurring DNA modification in prokaryotic and eukaryotic organisms and is involved in several biological processes. Although genome-wide methylation has been studied in many insects, the understanding of global and genomic DNA methylation during insect early embryonic development, is lacking especially for insect diapause. In this study, we analyzed the relationship between DNA methylomes and transcriptomes in diapause-destined eggs compared to diapause-terminated eggs in the silkworm, Bombyx mori (B. mori). The results revealed that methylation was sparse in this species, as previously reported. Moreover, methylation levels in diapause-terminated eggs (HCl-treated) were 0.05% higher than in non-treated eggs, mainly due to the contribution of CG methylation sites. Methylation tends to occur in the coding sequences and promoter regions, especially at transcription initiation sites and short interspersed elements. Additionally, 364 methylome- and transcriptome-associated genes were identified, which showed significant differences in methylation and expression levels in diapause-destined eggs when compared with diapause-terminated eggs, and 74% of methylome and transcriptome associated genes showed both hypermethylation and elevated expression. Most importantly, Kyoto Encyclopaedia of Genes and Genomes (KEGG) analyses showed that methylation may be positively associated with Bombyx mori embryonic development, by regulating cell differentiation, metabolism, apoptosis pathways and phosphorylation. Through analyzing the G2/M phase-specific E3 ubiquitin-protein ligase (G2E3), we speculate that methylation may affect embryo diapause by regulating the cell cycle in Bombyx mori. These findings will help unravel potential linkages between DNA methylation and gene expression during early insect embryonic development and insect diapause.
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Affiliation(s)
- Bing Li
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, Anhui, China; (B.L.); (P.H.); (L.-B.Z.); (L.-L.Y.); (H.-H.C.); (J.W.); (S.-Z.Z.); (S.T.)
- Institute of Sericulture, Anhui Academy of Agricultural Sciences, Hefei 230061, Anhui, China;
| | - Pei Hu
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, Anhui, China; (B.L.); (P.H.); (L.-B.Z.); (L.-L.Y.); (H.-H.C.); (J.W.); (S.-Z.Z.); (S.T.)
- Anhui International Joint Research and Developmental Center of Sericulture Resources Utilization, Hefei 230036, Anhui, China
| | - Lin-Bao Zhu
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, Anhui, China; (B.L.); (P.H.); (L.-B.Z.); (L.-L.Y.); (H.-H.C.); (J.W.); (S.-Z.Z.); (S.T.)
- Anhui International Joint Research and Developmental Center of Sericulture Resources Utilization, Hefei 230036, Anhui, China
| | - Ling-Ling You
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, Anhui, China; (B.L.); (P.H.); (L.-B.Z.); (L.-L.Y.); (H.-H.C.); (J.W.); (S.-Z.Z.); (S.T.)
- Anhui International Joint Research and Developmental Center of Sericulture Resources Utilization, Hefei 230036, Anhui, China
| | - Hui-Hua Cao
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, Anhui, China; (B.L.); (P.H.); (L.-B.Z.); (L.-L.Y.); (H.-H.C.); (J.W.); (S.-Z.Z.); (S.T.)
- Anhui International Joint Research and Developmental Center of Sericulture Resources Utilization, Hefei 230036, Anhui, China
| | - Jie Wang
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, Anhui, China; (B.L.); (P.H.); (L.-B.Z.); (L.-L.Y.); (H.-H.C.); (J.W.); (S.-Z.Z.); (S.T.)
- Anhui International Joint Research and Developmental Center of Sericulture Resources Utilization, Hefei 230036, Anhui, China
| | - Shang-Zhi Zhang
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, Anhui, China; (B.L.); (P.H.); (L.-B.Z.); (L.-L.Y.); (H.-H.C.); (J.W.); (S.-Z.Z.); (S.T.)
- Anhui International Joint Research and Developmental Center of Sericulture Resources Utilization, Hefei 230036, Anhui, China
| | - Ming-Hui Liu
- Institute of Sericulture, Anhui Academy of Agricultural Sciences, Hefei 230061, Anhui, China;
| | - Shahzad Toufeeq
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, Anhui, China; (B.L.); (P.H.); (L.-B.Z.); (L.-L.Y.); (H.-H.C.); (J.W.); (S.-Z.Z.); (S.T.)
- Anhui International Joint Research and Developmental Center of Sericulture Resources Utilization, Hefei 230036, Anhui, China
| | - Shou-Jun Huang
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, Anhui, China; (B.L.); (P.H.); (L.-B.Z.); (L.-L.Y.); (H.-H.C.); (J.W.); (S.-Z.Z.); (S.T.)
- Anhui International Joint Research and Developmental Center of Sericulture Resources Utilization, Hefei 230036, Anhui, China
| | - Jia-Ping Xu
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, Anhui, China; (B.L.); (P.H.); (L.-B.Z.); (L.-L.Y.); (H.-H.C.); (J.W.); (S.-Z.Z.); (S.T.)
- Anhui International Joint Research and Developmental Center of Sericulture Resources Utilization, Hefei 230036, Anhui, China
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11
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Matsushima D, Kasahara R, Matsuno K, Aoki F, Suzuki MG. Involvement of Ecdysone Signaling in the Expression of the doublesex Gene during Embryonic Development in the Silkworm, Bombyx mori. Sex Dev 2019; 13:151-163. [PMID: 31487710 DOI: 10.1159/000502361] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/07/2019] [Indexed: 01/09/2023] Open
Abstract
Steroid hormones, represented by estrogen and testosterone, act as sex hormones that play an essential role in the sexual differentiation of vertebrates. However, it remains unclear whether ecdysteroids, typical steroid hormones in insects, function as sex hormones. In this study, we investigated whether ecdysteroids or ecdysone signals are involved in the sexual differentiation of the silkworm (Bombyx mori) embryo. Quantitative analysis using LC-MS/MS demonstrated that there was no significant difference in the 20-hydroxyecdysone (20E) titer between sexes during embryonic development. Consistent with this result, expression levels of 2 genes encoding ecdysteroid-phosphate phosphatase (EPPase) and ecdysone 20-hydroxylase (E20OHase), which are essential for the biosynthesis of ecdysone and 20E in eggs, did not show a significant difference between male and female embryos. Expression levels of ecdysone receptor (EcR) and E75, which is one of a small set of genes induced directly by 20E, were also similar between the 2 sexes. However, knockdown of EPPase and one isoform of EcR (EcR-A) resulted in decreased expression of Bombyx doublesex (Bmdsx), a master regulatory gene for sexual differentiation of the silkworm in both male and female embryos. In vitro analysis with cultured testes revealed that expression levels of Bmdsx were increased in a dose-dependent manner of the ecdysone analog, ponasterone A. These results suggest that ecdysone signaling may play a role in indirectly regulating the expression of some genes involved in sexual differentiation through inducing expression of Bmdsx in the silkworm.
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12
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Gu SH, Lin PL, Hsieh HY. Bombyxin/Akt signaling in relation to the embryonic diapause process of the silkworm, Bombyx mori. J Insect Physiol 2019; 116:32-40. [PMID: 31022386 DOI: 10.1016/j.jinsphys.2019.04.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 04/17/2019] [Accepted: 04/18/2019] [Indexed: 06/09/2023]
Abstract
Our previous study showed that phosphorylation of glycogen synthase kinase (GSK)-3β is related to the embryonic diapause process in Bombyx. However, the upstream signaling pathway was not clearly understood. In the present study, we examined bombyxin/Akt signaling in relation to the embryonic diapause process of B. mori. Results showed that GSK-3β phosphorylation stimulated by dechorionation was blocked by LY294002, a specific phosphatidylinositol 3-kinase (PI3K) inhibitor, indicating involvement of PI3K in GSK-3β phosphorylation in dechorionated eggs. Direct determination of Akt phosphorylation showed that dechorionation stimulated Akt phosphorylation. The Akt phosphorylation was blocked by LY294002. Temporal changes in Akt phosphorylation showed that different changing patterns exist between diapause and developing eggs. Relatively higher phosphorylation levels of Akt were detected between days 3 and 5 after oviposition in non-diapause eggs compared to those at the same stages in diapause eggs. Upon treatment with HCl, which prevents diapause initiation, Akt phosphorylation levels exhibited a later and much broader peak compared to diapause eggs. Examination of expression levels of the bombyxin-Z1 gene showed that in diapause eggs, a major peak occurred 1 day after oviposition, and its level then sharply decreased on day 2. However, in both non-diapause and HCl-treated eggs, a major broad peak was detected between days 1 and 4 after oviposition. These temporal changes in bombyxin-Z1 gene expression levels during embryonic stages coincided with changes in Akt phosphorylation, indicating that bombyxin-Z1 is likely an upstream signaling component for Akt phosphorylation. Taken together, our results indicated that PI3K/Akt is an upstream signaling pathway for GSK-3β phosphorylation and is associated with the diapause process of B. mori eggs. To our knowledge, this is the first study to demonstrate the potential correlation between bombyxin/Akt signaling and the embryonic diapause process.
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Affiliation(s)
- Shi-Hong Gu
- Department of Biology, National Museum of Natural Science, 1 Kuan-Chien Road, Taichung 404, Taiwan, ROC.
| | - Pei-Ling Lin
- Department of Biology, National Museum of Natural Science, 1 Kuan-Chien Road, Taichung 404, Taiwan, ROC
| | - Hsiao-Yen Hsieh
- Department of Biology, National Museum of Natural Science, 1 Kuan-Chien Road, Taichung 404, Taiwan, ROC
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13
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Li B, Hu P, Zhang SZ, Toufeeq S, Wang J, Zhao K, Xu X, Xu JP, Huang SJ. DNA methyltransferase BmDnmt1 and BmDnmt2 in silkworm (Bombyx mori) and the regulation of silkworm embryonic development. Arch Insect Biochem Physiol 2019; 100:e21529. [PMID: 30588651 DOI: 10.1002/arch.21529] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
DNA methylation is one of the most widespread epigenetic marks and has been linked to insect development, especially influencing embryonic development. However, the regulation of DNA methylation in silkworm embryonic development and diapause remain to investigate. In this study, reverse-transcription quantitative polymerase chain reaction was performed to identify the expression level of Bombyx mori DNA methyltransferases (BmDNMTs) 1 and 2 ( BmDnmt1 and BmDnmt2) in different tissues, different embryonic developmental stages, and different strains of the silkworm. The results showed that BmDNMTs were the most highly expressed during embryonic development, especially at early embryonic stages. In particular, the expression of BmDNMTs was significantly upregulated in diapause-terminated eggs by HCl treatment. Moreover, tissue distribution showed that BmDnmt2 was highly expressed in testis and ovary, and BmDnmt1 was highly expressed in testis. This study contributes to understanding the correlation of DNA methylation occurs with embryogenesis and gametogenesis in insect, meanwhile, it provides a research orientation to further analyze the role of DNA methylation in diapause initiation and termination in insect embryonic development.
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Affiliation(s)
- Bing Li
- School of Life Sciences, Anhui Agricultural University, Hefei, China
- Anhui International Joint Research and Developmental Center of Sericulture Resources Utilization, Hefei, China
- Institute of Sericulture, Anhui Academy of Agricultural Sciences, Hefei, China
| | - Pei Hu
- School of Life Sciences, Anhui Agricultural University, Hefei, China
- Anhui International Joint Research and Developmental Center of Sericulture Resources Utilization, Hefei, China
| | - Shang-Zhi Zhang
- School of Life Sciences, Anhui Agricultural University, Hefei, China
- Anhui International Joint Research and Developmental Center of Sericulture Resources Utilization, Hefei, China
| | - Shahzad Toufeeq
- School of Life Sciences, Anhui Agricultural University, Hefei, China
- Anhui International Joint Research and Developmental Center of Sericulture Resources Utilization, Hefei, China
| | - Jie Wang
- School of Life Sciences, Anhui Agricultural University, Hefei, China
- Anhui International Joint Research and Developmental Center of Sericulture Resources Utilization, Hefei, China
| | - Kang Zhao
- School of Life Sciences, Anhui Agricultural University, Hefei, China
- Anhui International Joint Research and Developmental Center of Sericulture Resources Utilization, Hefei, China
| | - Xin Xu
- School of Life Sciences, Anhui Agricultural University, Hefei, China
- Anhui International Joint Research and Developmental Center of Sericulture Resources Utilization, Hefei, China
| | - Jia-Ping Xu
- School of Life Sciences, Anhui Agricultural University, Hefei, China
- Anhui International Joint Research and Developmental Center of Sericulture Resources Utilization, Hefei, China
| | - Shou-Jun Huang
- School of Life Sciences, Anhui Agricultural University, Hefei, China
- Anhui International Joint Research and Developmental Center of Sericulture Resources Utilization, Hefei, China
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14
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Xu X, Zhang Z, Yang Y, Huang S, Li K, He L, Zhou X. Genome editing reveals the function of Yorkie during the embryonic and early larval development in silkworm, Bombyx mori. Insect Mol Biol 2018; 27:675-685. [PMID: 29797485 DOI: 10.1111/imb.12502] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
As a transcriptional coactivator, Yorkie (Yki) is a major downstream target of the Hippo signalling pathway to regulate the organ size during animal development and regeneration. Previous microarray analysis in the silkworm, Bombyx mori, has shown that genes associated with the Hippo pathway were primarily expressed in gonads and imaginal discs. The RNA-interference-mediated silencing of Yki at the early wandering stage delayed B. mori development and ovary maturation, whereas baculovirus-mediated overexpression at the late larval instar facilitated organ growth and accelerated metamorphosis. Here, we employed CRISPR/Cas9-mediated mutagenesis to investigate the function of Yki in B. mori (BmYki) at the embryonic and early larval stages. Knocking out of BmYki led to reduced body size, moulting defects and, eventually, larval lethality. Sequence analysis of CRISPR/Cas9 mutants exhibited an array of deletions in BmYki. As a critical downstream effector of the Hippo kinase cassette, silencing of BmYki at the embryonic stage is indispensable and the consequence is lethal. Given that the Hippo signalling pathway is evolutionarily conserved, Yki has the potential to be a novel molecular target for genetic-based pest management practices.
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Affiliation(s)
- X Xu
- School of Life Science, East China Normal University, Shanghai, China
| | - Z Zhang
- School of Life Science, East China Normal University, Shanghai, China
| | - Y Yang
- School of Life Science, East China Normal University, Shanghai, China
| | - S Huang
- Agricultural and Medical Biotechnology, University of Kentucky, Lexington, KY, USA
| | - K Li
- School of Life Science, East China Normal University, Shanghai, China
| | - L He
- School of Life Science, East China Normal University, Shanghai, China
| | - X Zhou
- Department of Entomology, University of Kentucky, Lexington, KY, USA
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15
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Gu SH, Hsieh HY, Lin PL. Regulation of protein phosphatase 2A during embryonic diapause process in the silkworm, Bombyx mori. J Insect Physiol 2017; 103:117-124. [PMID: 28893508 DOI: 10.1016/j.jinsphys.2017.09.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 09/07/2017] [Accepted: 09/07/2017] [Indexed: 06/07/2023]
Abstract
Regulation of protein phosphorylation requires coordinated interactions between protein kinases and protein phosphatases. In the present study, we investigated regulation of protein phosphatase 2A (PP2A) during the embryonic diapause process of B. mori. An immunoblotting analysis showed that Bombyx eggs contained a catalytic C subunit, a major regulatory B subunit (B55/PR55 subunit), and a structural A subunit, with the A and B subunits undergoing differential changes between diapause and non-diapause eggs during embryonic process. In non-diapause eggs, eggs whose diapause initiation was prevented by HCl, and eggs in which diapause had been terminated by chilling of diapausing eggs at 5°C for 70days and then were transferred to 25°C, protein levels of the A and B subunits of PP2A gradually increased toward embryonic development. However, protein levels of the A and B subunits in diapause eggs remained at low levels during the first 8days after oviposition. The direct determination of PP2A enzymatic activity showed that the activity remained at low levels in diapause eggs during the first 8days after oviposition. However, in non-diapause eggs, eggs whose diapause initiation was prevented by HCl, and eggs in which diapause had been terminated by chilling, PP2A enzymatic activity sharply increased during the first several days, reached a peak during the middle embryonic development, and then greatly decreased 3 or 4days before hatching. Examination of temporal changes in mRNA expression levels of the catalytic β subunit and regulatory subunit of PP2A showed high levels in eggs whose diapause initiation was prevented by HCl compared to those in diapause eggs. These results demonstrate that the higher PP2A gene expression and PP2A A and B subunit protein levels and increased enzymatic activity are related to embryonic development of B. mori.
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Affiliation(s)
- Shi-Hong Gu
- Department of Biology, National Museum of Natural Science, 1 Kuan-Chien Road, Taichung 404, Taiwan, ROC.
| | - Hsiao-Yen Hsieh
- Department of Biology, National Museum of Natural Science, 1 Kuan-Chien Road, Taichung 404, Taiwan, ROC
| | - Pei-Ling Lin
- Department of Biology, National Museum of Natural Science, 1 Kuan-Chien Road, Taichung 404, Taiwan, ROC
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16
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Tao H, Li X, Qiu JF, Liu HJ, Zhang DY, Chu F, Sima Y, Xu SQ. The light cycle controls the hatching rhythm in Bombyx mori via negative feedback loop of the circadian oscillator. Arch Insect Biochem Physiol 2017; 96:e21408. [PMID: 28872696 DOI: 10.1002/arch.21408] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Hatching behavior is a key target in silkworm (Bombyx mori) rearing, especially for the control of Lepidoptera pests. According to previous research, hatching rhythms appear to be controlled by a clock mechanism that restricts or "gates" hatching to a particular time. However, the underlying mechanism remains elusive. Under 12-h light:12-h dark photoperiod (LD) conditions, the transcriptional levels of the chitinase5 (Cht5) and hatching enzyme-like (Hel) genes, as well as the enzymatic activities of their gene products, oscillated in time with ambient light cycles, as did the transcriptional levels of the cryptochrome 1, cryptochrome 2, period (per), and timeless genes, which are key components of the negative feedback loop of the circadian rhythm. These changes were related to the expression profile of the ecdysteroid receptor gene and the hatching behavior of B. mori eggs. However, under continuous light or dark conditions, the hatching behavior, the expression levels of Cht5 and Hel, as well as the enzymatic activities of their gene products, were not synchronized unlike under LD conditions. In addition, immunohistochemistry experiments showed that light promoted the translocation of PER from the cytoplasm to the nucleus. In conclusion, LD cycles regulate the hatching rhythm of B. mori via negative feedback loop of the circadian oscillator.
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Affiliation(s)
- Hui Tao
- School of Biology and Basic Medical Sciences, Medical College, Soochow University, Suzhou, China
- Institute of Agricultural Biotechnology & Ecology (IABE), Soochow University, Suzhou, China
| | - Xue Li
- School of Biology and Basic Medical Sciences, Medical College, Soochow University, Suzhou, China
- Institute of Agricultural Biotechnology & Ecology (IABE), Soochow University, Suzhou, China
| | - Jian-Feng Qiu
- School of Biology and Basic Medical Sciences, Medical College, Soochow University, Suzhou, China
- Institute of Agricultural Biotechnology & Ecology (IABE), Soochow University, Suzhou, China
| | - Heng-Jiang Liu
- School of Biology and Basic Medical Sciences, Medical College, Soochow University, Suzhou, China
| | - Da-Yan Zhang
- School of Biology and Basic Medical Sciences, Medical College, Soochow University, Suzhou, China
| | - Feng Chu
- School of Biology and Basic Medical Sciences, Medical College, Soochow University, Suzhou, China
| | - Yanghu Sima
- School of Biology and Basic Medical Sciences, Medical College, Soochow University, Suzhou, China
- Institute of Agricultural Biotechnology & Ecology (IABE), Soochow University, Suzhou, China
- National Engineering Laboratory for Modern Silk (NEAER), Soochow University, Suzhou, China
| | - Shi-Qing Xu
- School of Biology and Basic Medical Sciences, Medical College, Soochow University, Suzhou, China
- Institute of Agricultural Biotechnology & Ecology (IABE), Soochow University, Suzhou, China
- National Engineering Laboratory for Modern Silk (NEAER), Soochow University, Suzhou, China
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Zhang J, Blessing D, Wu C, Liu N, Li J, Qin S, Li M. Comparative transcriptomes analysis of the wing disc between two silkworm strains with different size of wings. PLoS One 2017; 12:e0179560. [PMID: 28617839 PMCID: PMC5472328 DOI: 10.1371/journal.pone.0179560] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 05/30/2017] [Indexed: 12/19/2022] Open
Abstract
Wings of Bombyx mori (B. mori) develop from the primordium, and different B. mori strains have different wing types. In order to identify the key factors influencing B. mori wing development, we chose strains P50 and U11, which are typical for normal wing and minute wing phenotypes, respectively. We dissected the wing disc on the 1st-day of wandering stage (P50D1 and U11D1), 2nd-day of wandering stage (P50D2 and U11D2), and 3rd-day of wandering stage (P50D3 and U11D3). Subsequently, RNA-sequencing (RNA-Seq) was performed on both strains in order to construct their gene expression profiles. P50 exhibited 628 genes differentially expressed to U11, 324 up-regulated genes, and 304 down-regulated genes. Five enriched gene ontology (GO) terms were identified by GO enrichment analysis based on these differentially expressed genes (DEGs). KEGG enrichment analysis results showed that the DEGs were enriched in five pathways; of these, we identified three pathways related to the development of wings. The three pathways include amino sugar and nucleotide sugar metabolism pathway, proteasome signaling pathway, and the Hippo signaling pathway. The representative genes in the enrichment pathways were further verified by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). The RNA-Seq and qRT-PCR results were largely consistent with each other. Our results also revealed that the significantly different genes obtained in our study might be involved in the development of the size of B. mori wings. In addition, several KEGG enriched pathways might be involved in the regulation of the pathways of wing formation. These results provide a basis for further research of wing development in B. mori.
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Affiliation(s)
- Jing Zhang
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, China
| | - Danso Blessing
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, China
| | - Chenyu Wu
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, China
| | - Na Liu
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, China
| | - Juan Li
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, China
| | - Sheng Qin
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, China
- The Sericultural Research Institute, Chinese Academy of Agricultural Science, Zhenjiang, Jiangsu, China
- * E-mail: (ML); (SQ)
| | - Muwang Li
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, China
- The Sericultural Research Institute, Chinese Academy of Agricultural Science, Zhenjiang, Jiangsu, China
- * E-mail: (ML); (SQ)
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18
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Gu SH, Chen CH. Injury-induced rapid activation of MAPK signaling in dechorionated eggs and larvae of the silkworm Bombyx mori. Insect Sci 2017; 24:248-258. [PMID: 26619971 DOI: 10.1111/1744-7917.12301] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/29/2015] [Indexed: 06/05/2023]
Abstract
Previous study showed that diapause in Bombyx mori eggs can be terminated by dechorionation and that activation in the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) in dechorionated cultured eggs is involved in diapause termination. In the present study, the possible mechanism underlying activation of ERK upon dechorionation was further investigated. Results showed that mechanical injury of diapause eggs without medium incubation also resulted in rapid increase in the phospho-ERK levels and that injury increased the phospho-ERK levels at different stages of both diapause eggs and eggs in which diapause initiation was prevented by HCl. Effects of anaerobiosis on dechorionation-stimulated phospho-ERK levels showed that the mechanical injury itself but not the dramatic increase in oxygen uptake upon injury is involved in a rapid activation of ERK. Chemical anaerobiosis on dechorionation-stimulated phospho-ERK levels and the in vivo effect of anaerobiosis showed that the supply of oxygen also plays a role in ERK signaling. In addition, injury induced the phosphorylation of c-jun N-terminal kinases (JNKs) and p38 kinase, components of two parallel MAPK pathways. A kinase assay showed a dramatic increase in JNK kinase activity in egg lysates upon injury. When newly hatched first instar larvae were injured, an increase in the phospho-ERK levels similar to that in dechorionated eggs was observed. From the results, we hypothesize that the injury-induced rapid activation of MAPK signaling, which serves as a natural signal for embryonic development, is related to diapause termination in dechorionated eggs.
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Affiliation(s)
- Shi-Hong Gu
- Department of Biology, National Museum of Natural Science, Taichung, Taiwan, China
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Sumitani M, Kondo M, Kasashima K, Endo H, Nakamura K, Misawa T, Tanaka H, Sezutsu H. Characterization of Bombyx mori mitochondrial transcription factor A, a conserved regulator of mitochondrial DNA. Gene 2016; 608:103-113. [PMID: 28027964 DOI: 10.1016/j.gene.2016.12.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 12/20/2016] [Indexed: 01/18/2023]
Abstract
In the present study, we initially cloned and characterized a mitochondrial transcription factor A (Tfam) homologue in the silkworm, Bombyx mori. Bombyx mori TFAM (BmTFAM) localized to mitochondria in cultured silkworm and human cells, and co-localized with mtDNA nucleoids in human HeLa cells. In an immunoprecipitation analysis, BmTFAM was found to associate with human mtDNA in mitochondria, indicating its feature as a non-specific DNA-binding protein. In spite of the low identity between BmTFAM and human TFAM (26.5%), the expression of BmTFAM rescued mtDNA copy number reductions and enlarged mtDNA nucleoids in HeLa cells, which were induced by human Tfam knockdown. Thus, BmTFAM compensates for the function of human TFAM in HeLa cells, demonstrating that the mitochondrial function of TFAM is highly conserved between silkworms and humans. BmTfam mRNA was strongly expressed in early embryos. Through double-stranded RNA (dsRNA)-based RNA interference (RNAi) in silkworm embryos, we found that the knockdown of BmTFAM reduced the amount of mtDNA and induced growth retardation at the larval stage. Collectively, these results demonstrate that BmTFAM is a highly conserved mtDNA regulator and may be a good candidate for investigating and modulating mtDNA metabolism in this model organism.
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Affiliation(s)
- Megumi Sumitani
- Transgenic Silkworm Research Unit, Division of Biotechnology, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Owashi, Tsukuba 305-8634, Japan.
| | - Mari Kondo
- Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa 277-8562, Chiba, Japan
| | - Katsumi Kasashima
- Division of Functional Biochemistry, Department of Biochemistry, Jichi Medical University, Shimotsuke, Tochigi 329-0498, Japan
| | - Hitoshi Endo
- Division of Functional Biochemistry, Department of Biochemistry, Jichi Medical University, Shimotsuke, Tochigi 329-0498, Japan
| | - Kaoru Nakamura
- Transgenic Silkworm Research Unit, Division of Biotechnology, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Owashi, Tsukuba 305-8634, Japan
| | - Toshihiko Misawa
- Transgenic Silkworm Research Unit, Division of Biotechnology, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Owashi, Tsukuba 305-8634, Japan
| | - Hiromitsu Tanaka
- Insect-Microbe Research Unit, Division of Insect Sciences, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Owashi, Tsukuba 305-8634, Japan
| | - Hideki Sezutsu
- Transgenic Silkworm Research Unit, Division of Biotechnology, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Owashi, Tsukuba 305-8634, Japan; Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa 277-8562, Chiba, Japan.
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Wang D, Zhang Y, Dong Z, Guo P, Ma S, Guo K, Xia Q, Zhao P. Serine protease P-IIc is responsible for the digestion of yolk proteins at the late stage of silkworm embryogenesis. Insect Biochemistry and Molecular Biology 2016; 74:42-49. [PMID: 27137459 DOI: 10.1016/j.ibmb.2016.03.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Revised: 03/15/2016] [Accepted: 03/16/2016] [Indexed: 06/05/2023]
Abstract
In silkworms, yolk proteins comprise vitellin, egg-specific protein and 30K proteins, which are sequentially degraded by endogenous proteases strictly regulated during embryogenesis. Although the process has been extensively investigated, there is still a gap in the knowledge about the degradation of silkworm yolk proteins on the last two days of embryonic development. In the present study, we isolated and purified a gut serine protease P-IIc, which demonstrated optimal activity at 25 °C and pH 11. Semi-quantitative RT-PCR combined with western blotting showed that P-IIc was actively expressed and significantly accumulated in the gut on the last two days of embryogenesis. When natural yolk proteins were incubated with P-IIc in vitro, vitellin and ESP were selectively degraded. P-IIc also demonstrated activity towards 30K proteins as evidenced by rapid and complete digestion of BmLP1 and partial digestion of BmLP2 and BmLP3. Furthermore, RNAi knockdown of P-IIc in silkworm embryos significantly reduced the degradation rate of residual yolk proteins on embryonic day 10. Taken together, our results indicate that P-IIc represents an embryonic gut protease with a relatively broad substrate specificity, which plays an important role in the degradation of yolk proteins at the late stage of silkworm embryogenesis.
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Affiliation(s)
- Dandan Wang
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400716, China
| | - Yan Zhang
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400716, China
| | - Zhaoming Dong
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400716, China
| | - Pengchao Guo
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400716, China
| | - Sanyuan Ma
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400716, China
| | - Kaiyu Guo
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400716, China
| | - Qingyou Xia
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400716, China
| | - Ping Zhao
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400716, China.
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Xin HH, Zhang DP, Chen RT, Cai ZZ, Lu Y, Liang S, Miao YG. TRANSCRIPTION FACTOR Bmsage PLAYS A CRUCIAL ROLE IN SILK GLAND GENERATION IN SILKWORM, Bombyx mori. Arch Insect Biochem Physiol 2015; 90:59-69. [PMID: 25917878 DOI: 10.1002/arch.21244] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Salivary gland secretion is altered in Drosophila embryos with loss of function of the sage gene. Saliva has a reduced volume and an increased electron density according to transmission electron microscopy, resulting in regions of tube dilation and constriction with intermittent tube closure. However, the precise functions of Bmsage in silkworm (Bombyx mori) are unknown, although its sequence had been deposited in SilkDB. From this, Bmsage is inferred to be a transcription factor that regulates the synthesis of silk fibroin and interacts with another silk gland-specific transcription factor, namely, silk gland factor-1. In this study, we introduced a germline mutation of Bmsage using the Cas9/sgRNA system, a genome-editing technology, resulting in deletion of Bmsage from the genome of B. mori. Of the 15 tested samples, seven displayed alterations at the target site. The mutagenesis efficiency was about 46.7% and there were no obvious off-target effects. In the screened homozygous mutants, silk glands developed poorly and the middle and posterior silk glands (MSG and PSG) were absent, which was significantly different from the wild type. The offspring of G0 mosaic silkworms had indel mutations causing 2- or 9-bp deletions at the target site, but exhibited the same abnormal silk gland structure. Mutant larvae containing different open-reading frames of Bmsage had the same silk gland phenotype. This illustrated that the mutant phenotype was due to Bmsage knockout. We conclude that Bmsage participates in embryonic development of the silk gland.
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Affiliation(s)
- Hu-hu Xin
- Institute of Sericulture and Apiculture, College of Animal Sciences, Zhejiang University, Hangzhou, People's Republic of China
| | - Deng-pan Zhang
- Institute of Sericulture and Apiculture, College of Animal Sciences, Zhejiang University, Hangzhou, People's Republic of China
| | - Rui-ting Chen
- Institute of Sericulture and Apiculture, College of Animal Sciences, Zhejiang University, Hangzhou, People's Republic of China
| | - Zi-zheng Cai
- Institute of Sericulture and Apiculture, College of Animal Sciences, Zhejiang University, Hangzhou, People's Republic of China
| | - Yan Lu
- Institute of Sericulture and Apiculture, College of Animal Sciences, Zhejiang University, Hangzhou, People's Republic of China
| | - Shuang Liang
- Institute of Sericulture and Apiculture, College of Animal Sciences, Zhejiang University, Hangzhou, People's Republic of China
| | - Yun-gen Miao
- Institute of Sericulture and Apiculture, College of Animal Sciences, Zhejiang University, Hangzhou, People's Republic of China
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Zhang Z, Aslam AFM, Liu X, Li M, Huang Y, Tan A. Functional analysis of Bombyx Wnt1 during embryogenesis using the CRISPR/Cas9 system. J Insect Physiol 2015; 79:73-79. [PMID: 26070541 DOI: 10.1016/j.jinsphys.2015.06.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Revised: 06/07/2015] [Accepted: 06/08/2015] [Indexed: 06/04/2023]
Abstract
Recently established, custom-designed nuclease technologies such as the clustered regularly interspaced short palindromic repeat (CRISPR)-associated system provide attractive genome editing tools. Targeted gene mutagenesis using the CRISPR/Cas9 system has been achieved in several orders of insects. However, outside of studies on Drosophila melanogaster and the lepidopteron model insect Bombyx mori, little success has been reported, which is largely due to a lack of effective genetic manipulation tools that can be used in other insect orders. To create a simple and effective method of gene knockout analysis, especially for dissecting gene functioning during insect embryogenesis, we performed a functional analysis of the Bombyx Wnt1 (BmWnt1) gene using Cas9/sgRNA-mediated gene mutagenesis. The Wnt1 gene is required for embryonic patterning in various organisms, and its crucial roles during embryogenesis have been demonstrated in several insect orders. Direct injection of Cas9 mRNA and BmWnt1-specific sgRNA into Bombyx embryos induced a typical Wnt-deficient phenotype: injected embryos could not hatch and exhibited severe defects in body segmentation and pigmentation in a dose-dependent manner. Quantitative real-time PCR (qRT-PCR) analysis revealed that Hox genes were down-regulated after BmWnt1 depletion. Furthermore, large deletion, up to 18Kb, ware generated. The current study demonstrates that using the CRISPR/Cas9 system is a promising approach to achieve targeted gene mutagenesis during insect embryogenesis.
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Affiliation(s)
- Zhongjie Zhang
- Sericultural Research Institute, Jiangsu University of Science and Technology, Zhenjiang 212018, Jiangsu, China; 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
| | - Abu F M Aslam
- 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
| | - Xiaojing Liu
- Sericultural Research Institute, Jiangsu University of Science and Technology, Zhenjiang 212018, Jiangsu, China
| | - Muwang Li
- Sericultural Research Institute, Jiangsu University of Science and Technology, Zhenjiang 212018, Jiangsu, 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
| | - 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.
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Chen A, Liao P, Li Q, Zhao Q, Yang W, Zhu S, Wu F, He R, Dong Z, Huang P. The Structural Variation Is Associated with the Embryonic Lethality of a Novel Red Egg Mutant Fuyin-lre of Silkworm, Bombyx mori. PLoS One 2015; 10:e0128211. [PMID: 26030868 PMCID: PMC4452371 DOI: 10.1371/journal.pone.0128211] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Accepted: 04/23/2015] [Indexed: 11/23/2022] Open
Abstract
Bombyx mori presents several types of egg color mutations, all of which have been extensively discussed in sericulture. While the red egg mutation has been previously observed, lethal red-egg mutants have not been reported. In the present work, the red egg mutant Fuyin-lre (Fuyin-lethal red egg) was discovered from the Fuyin germplasm resource of B. mori. This mutant features red-colored eggs and embryonic lethality. Genetic analysis showed that Fuyin-lre follows recessive inheritance, with the red egg gene re governing the egg color, and the embryonic lethality of Fuyin-lre may be caused by mutations of other genes closely linked to re. Digital gene expression (DGE) was employed to compare the transcription profiles of Fuyin and Fuyin-lre eggs after 24 and 48 h of incubation. A total of 48 differentially expressed genes followed the same expression patterns in both groups at both time points (FDR < 0.01 and log 2 Ratio ≥ 1). Further analyses indicated that 8 out of the 48 genes (including re) were closely linked to re. These 8 genes were highly expressed in wild-type Fuyin and the red egg mutant re but showed nearly absent expression in Fuyin-lre. Sequencing of the re gene confirmed that the re gene itself does not induce embryonic lethality, and structure analysis showed that the structural variation of the region where the 8 genes were located may be associated with the embryonic lethality of Fuyin-lre. The present work provides a good foundation for future studies on the mechanism of embryonic lethality and embryonic development in Fuyin-lre.
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Affiliation(s)
- Anli Chen
- The Sericultural and Apicultural Research Institute, Yunnan Academy of Agricultural Sciences, Mengzi Yunnan, China
| | - Pengfei Liao
- The Sericultural and Apicultural Research Institute, Yunnan Academy of Agricultural Sciences, Mengzi Yunnan, China
| | - Qiongyan Li
- The Sericultural and Apicultural Research Institute, Yunnan Academy of Agricultural Sciences, Mengzi Yunnan, China
| | - Qiaoling Zhao
- Sericultural Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang Jiangsu, China
| | - Weike Yang
- The Sericultural and Apicultural Research Institute, Yunnan Academy of Agricultural Sciences, Mengzi Yunnan, China
| | - Shuifen Zhu
- The Sericultural and Apicultural Research Institute, Yunnan Academy of Agricultural Sciences, Mengzi Yunnan, China
| | - Fang Wu
- Sericultural Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang Jiangsu, China
| | - Rongfan He
- Sericultural Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang Jiangsu, China
| | - Zhanpeng Dong
- The Sericultural and Apicultural Research Institute, Yunnan Academy of Agricultural Sciences, Mengzi Yunnan, China
- * E-mail: (ZD); (PH)
| | - Ping Huang
- The Sericultural and Apicultural Research Institute, Yunnan Academy of Agricultural Sciences, Mengzi Yunnan, China
- * E-mail: (ZD); (PH)
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Shen G, Lin Y, Yang C, Xing R, Zhang H, Chen E, Han C, Liu H, Zhang W, Xia Q. Vertebrate estrogen regulates the development of female characteristics in silkworm, Bombyx mori. Gen Comp Endocrinol 2015; 210:30-7. [PMID: 25285397 DOI: 10.1016/j.ygcen.2014.09.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Revised: 09/01/2014] [Accepted: 09/20/2014] [Indexed: 11/30/2022]
Abstract
The vertebrate estrogens include 17-β-estradiol (E2), which has an analog in silkworm ovaries. In this study, the Bombyx mori vitellogenin gene (BmVg) was used as a biomarker to analyze the function of the E2 in silkworm. In most oviparous animals, Vg has female-specific expression. However, BmVg expression was also detected in B. mori males. Stage specific fluctuation of BmVg expression was similar in males and females, but expression levels in males were lower than in females. E2 treatment by injection or feeding of male larvae in the final instar stage induced and stimulated male BmVg transcription and protein synthesis. When silkworm ovary primordia were transplanted into males, BmVg was induced in male fat bodies. Transplanted ovaries primordia were also able to develop into ovaries and produce mature eggs. When females were treated with E2 promoted BmVg/BmVn protein accumulation in hemolymph, ovaries and eggs. However, BmVg transcription was decreased in female fat bodies. An E2 analog was identified in the hemolymph of day 3 wandering silkworms using high-performance liquid chromatography. Estradiol titers from fifth late-instar larvae to pupal stage were determined by enzyme-linked immunosorbent assay. The results suggested that silkworms synthesized a vertebrate E2 analog. This study found that E2 promoted the synthesis of BmVg, a female typical protein in silkworms.
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Affiliation(s)
- Guanwang Shen
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Ying Lin
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Congwen Yang
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Runmiao Xing
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Haiyan Zhang
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Enxiang Chen
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Chaoshan Han
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Hongling Liu
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Weiwei Zhang
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Qingyou Xia
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China.
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Jingade AH, Lekha G, Srinivasa BGK, Manjula A, Sivaprasad V. A feasibility study towards cryopreservation of silkworm eggs: response of non-diapause silkworm eggs to low temperature. Cryo Letters 2015; 36:19-24. [PMID: 26017168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Insect embryos are very sensitive to chilling temperatures and vary with species and their developmental stages. Insect eggs are small and can supercool to temperatures ranging from -5 degrees C to -40 degrees C. In general, insects rely on a variety of ecological and physiological adaptations to survive low temperatures, making cryopreservation technique significantly complex. Mulberry silkworm (Bombyx mori L., Lepidoptera: Bombycidae) eggs are cleidoic with chorion (approximately 20-25 μm thick). Preservation of non-diapause eggs to a limited period is practiced usually to delay hatching. The advantage of early embryonic periods having resistance to low temperature is utilized for chilling of eggs and preservation for long periods. However, technique for cryopreservation of silkworm eggs is not yet developed and the identification of precise embryonic stage and chill sensitivity is necessary for effective silkworm cryopreservation. The paper reports the chill-sensitivity and tolerance of non-diapause silkworm embryos of mulberry silkworm at various embryonic stages. Silkworm embryo of 48h-age are relatively chill-sensitive as compared to other embryonic ages. This is vital information for the development of cryopreservation protocol for silkworm eggs.
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Sirigineedi S, Vijayagowri E, Murthy GN, Rao G, Ponnuvel KM. Molecular characterization of DnaJ 5 homologs in silkworm Bombyx mori and its expression during egg diapause. Insect Sci 2014; 21:677-686. [PMID: 23956244 DOI: 10.1111/1744-7917.12048] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/08/2013] [Indexed: 06/02/2023]
Abstract
A comparison of the cDNA sequences (1 056 bp) of Bombyx mori DnaJ 5 homolog with B. mori genome revealed that unlike in other Hsps, it has an intron of 234 bp. The DnaJ 5 homolog contains 351 amino acids, of which 70 contain the conserved DnaJ domain at the N-terminal end. This homolog of B. mori has all desirable functional domains similar to other insects, and the 13 different DnaJ homologs identified in B. mori genome were distributed on different chromosomes. The expressed sequence tag database analysis of Hsp40 gene expression revealed higher expression in wing disc followed by diapause-induced eggs. Microarray analysis revealed higher expression of DnaJ 5 homolog at 18th h after oviposition in diapause-induced eggs. Further validation of DnaJ 5 expression through qPCR in diapause-induced and nondiapause eggs at different time intervals revealed higher expression in diapause eggs at 18 and 24 h after oviposition, which coincided with the expression of Hsp70 as the Hsp 40 is its co-chaperone. This study thus provides an outline of the genome organization of Hsp40 gene, and its role in egg diapause induction in B. mori.
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Affiliation(s)
- Sasibhushan Sirigineedi
- Genomics Division, Seribiotech Research Laboratory, Carmelaram Post, Kodathi, Bangalore, 560035, Karnataka, India
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Xu J, Wang Y, Li Z, Ling L, Zeng B, James AA, Tan A, Huang Y. Transcription activator-like effector nuclease (TALEN)-mediated female-specific sterility in the silkworm, Bombyx mori. Insect Mol Biol 2014; 23:800-7. [PMID: 25125145 PMCID: PMC4412852 DOI: 10.1111/imb.12125] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Engineering sex-specific sterility is critical for developing transgene-based sterile insect technology. Targeted genome engineering achieved by customized zinc-finger nuclease, transcription activator-like effector nuclease (TALEN) or clustered, regularly interspaced, short palindromic repeats/Cas9 systems has been exploited extensively in a variety of model organisms; however, screening mutated individuals without a detectable phenotype is still challenging. In addition, genetically recessive mutations only detectable in homozygotes make the experiments time-consuming. In the present study, we model a novel genetic system in the silkworm, Bombyx mori, that results in female-specific sterility by combining transgenesis with TALEN technologies. This system induces sex-specific sterility at a high efficiency by targeting the female-specific exon of the B. mori doublesex (Bmdsx) gene, which has sex-specific splicing isoforms regulating somatic sexual development. Transgenic animals co-expressing TALEN left and right arms targeting the female-specific Bmdsx exon resulted in somatic mutations and female mutants lost fecundity because of lack of egg storage and abnormal external genitalia. The wild-type sexual dimorphism of abdominal segment was not evident in mutant females. In contrast, there were no deleterious effects in mutant male moths. The current somatic TALEN technologies provide a promising approach for future insect functional genetics, thus providing the basis for the development of attractive genetic alternatives for insect population management.
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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
| | - Yueqiang Wang
- 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
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lin Ling
- 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
| | - Anthony A. James
- Departments of Microbiology & Molecular Genetics and Molecular Biology & Biochemistry, University of California, Irvine, CA 92697-3900
| | - 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
- Correspondence: Y.P. Huang, ; Tel: 86-2154924046; Fax: 86- 2154924014; AJ.. Tan, ; Tel: 86-2154924046; Fax: 86- 2154924014
| | - 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
- Correspondence: Y.P. Huang, ; Tel: 86-2154924046; Fax: 86- 2154924014; AJ.. Tan, ; Tel: 86-2154924046; Fax: 86- 2154924014
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Chen L, You Z, Xia H, Tang Q, Zhou Y, Yao Q, Chen K. Spatiotemporal expression profile of the Pumilio gene in the embryonic development of silkworm. ACTA ACUST UNITED AC 2014; 69:317-24. [PMID: 25265852 DOI: 10.5560/znc.2013-0142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
We previously identified a pumilio gene in silkworm (Bombyx mori L.), designated BmPUM, which was specifically expressed in the ovary and testis. To further characterize this gene's involvement in silkworm development, we have determined the spatiotemporal expression pattern of BmPUM during all embryonic stages. Real-time polymerase chain reaction (RT-PCR) analysis revealed that BmPUM was expressed in all stages of silkworm embryos and that its transcript levels displayed two distinct peaks. The first was observed at the germ-band formation stage (1 d after oviposition) and dropped to a low level at the gonad formation stage (5 d after oviposition). The second was detected at the stage of bristle follicle occurrence (6 d after oviposition), which was confirmed by Western blot analysis and immunohistochemistry. Nanos (Nos), functioning together with Pum in abdomen formation of Drosophila embryos, was also highly expressed at the beginning (0 h to 1 d after oviposition) of embryogenesis, but its transcript levels were very low after the stage of germ-band formation. These results suggest that BmPUM functions with Bombyx mori nanos (Bm-nanos) at the early stages of silkworm embryonic development, and may then play a role in gonad formation and the occurrence of bristle follicles. Our data thus provide a foundation to uncover the role of BmPUM during silkworm development.
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Kobayashi N, Takahashi M, Kihara S, Niimi T, Yamashita O, Yaginuma T. Cloning of cDNA encoding a Bombyx mori homolog of human oxidation resistance 1 (OXR1) protein from diapause eggs, and analyses of its expression and function. J Insect Physiol 2014; 68:58-68. [PMID: 25010546 DOI: 10.1016/j.jinsphys.2014.06.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Revised: 05/24/2014] [Accepted: 06/19/2014] [Indexed: 06/03/2023]
Abstract
To better understand the molecular mechanisms of diapause initiation, we used the sensitive cDNA subtraction (selective amplification via biotin- and restriction-mediated enrichment) method and isolated a novel gene expressed abundantly in diapause eggs of the silkworm, Bombyx mori, which encodes a homolog of the human oxidation resistance 1 (OXR1) protein. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting analyses confirmed that BmOXR1 mRNA and its 140-kDa protein were differentially expressed in diapause eggs compared to non-diapause eggs. OXR1 double-stranded RNA (dsRNA) was injected into diapause-destined eggs before the cellular blastoderm stage, and 4days later, when untreated eggs reached the diapause stage, the OXR1 protein disappeared; however, these eggs remained in diapause, suggesting that BmOXR1 is not essential for diapause initiation and/or maintenance. To further investigate the in vivo function of BmOXR1 apart from its role in diapause, we overexpressed BmOXR1 in Drosophila melanogaster. The fruit fly male adult life-span was significantly extended in the 50%-survival time when adults were reared on diets both with and without H2O2 solution under 25°C incubation. These results suggest that BmOXR1 functions in D. melanogaster via a possible antioxidant effect. As BmOXR1 was expressed mainly in the nuclei of D. melanogaster cells, the mechanism underlying its antioxidation effect appears to be different from that in humans where it is expressed mainly in the mitochondria. Taken together, these results suggest that BmOXR1 might serve as an antioxidant regulator during the early diapause stage.
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Affiliation(s)
- Noriko Kobayashi
- Laboratory of Sericulture & Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya, Aichi 464-8601, Japan
| | - Masaki Takahashi
- Laboratory of Sericulture & Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya, Aichi 464-8601, Japan
| | - Shouhei Kihara
- Laboratory of Sericulture & Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya, Aichi 464-8601, Japan
| | - Teruyuki Niimi
- Laboratory of Sericulture & Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya, Aichi 464-8601, Japan
| | - Okitsugu Yamashita
- Laboratory of Sericulture & Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya, Aichi 464-8601, Japan
| | - Toshinobu Yaginuma
- Laboratory of Sericulture & Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya, Aichi 464-8601, Japan.
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Abstract
Pigmentation during insect development is a primal adaptive requirement. In the silkworm, melanin is the primary component of larval pigments. The rate limiting substrate in melanin synthesis is tyrosine, which is converted from phenylalanine by the rate-limiting enzyme phenylalanine hydroxylase (PAH). While the role of tyrosine, derived from phenylalanine, in the synthesis of fiber proteins has long been known, the role of PAH in melanin synthesis is still unknown in silkworm. To define the importance of PAH, we cloned the cDNA sequence of BmPAH and expressed its complete coding sequence using the Bac-to-Bac baculovirus expression system. Purified recombinant protein had high PAH activity, some tryptophan hydroxylase activity, but no tyrosine hydroxylase activity, which are typical properties of PAH in invertebrates. Because melanin synthesis is most robust during the embryonic stage and larval integument recoloring stage, we injected BmPAH dsRNA into silkworm eggs and observed that decreasing BmPAH mRNA reduced neonatal larval tyrosine and caused insect coloration to fail. In vitro cultures and injection of 4th instar larval integuments with PAH inhibitor revealed that PAH activity was essential for larval marking coloration. These data show that BmPAH is necessary for melanin synthesis and we propose that conversion of phenylalanine to tyrosine by PAH is the first step in the melanin biosynthetic pathway in the silkworm.
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Affiliation(s)
- Ping Chen
- State Key Laboratory of Silkworm Genome Biology and College of Biotechnology, Southwest University, Chongqing, China ; College of Biotechnology, Southwest University, Chongqing, China
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Hu Y, Hamamoto H, Sekimizu K. Use of silkworms to evaluate the pathogenicity of bacteria attached to cedar pollen. Drug Discov Ther 2013; 7:153-157. [PMID: 24071577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Injection of a Japanese cedar pollen suspension into silkworm hemolymph kills the silkworms. A certain species of bacteria proliferated in the hemolymph of the dead silkworms. A 16S rDNA analysis demonstrated that the proliferating bacteria were Bacillus cereus, Bacillus thuringiensis, Bacillus weihenstephanensis, and Bacillus amyloliquefaciens. Among them, B. cereus, B. thuringiensis, and B. weihenstephanensis exhibited hemolysis against sheep red blood cells and were lethal to mice. A culture filtrate of B. amyloliquefaciens showed enzyme activity toward the pectic membrane of cedar pollen. These results suggest that silkworms as an animal model are useful for evaluating the pathogenicity of bacteria attached to cedar pollen.
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Affiliation(s)
- Yuan Hu
- Laboratory of Microbiology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
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32
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Abstract
HCl treatment has been, for about 80 years, the primary method for the prevention of entry into embryonic diapauses of Bombyx mori. This is because no method is as effective as the HCl treatment. In this study, we discovered that dimethyl sulfoxide (DMSO) prevented entry into the diapause of the silkworm, Bombyx mori. The effect of diapause prevention was 78% as a result of treatment with 100% DMSO concentration, and the effect was comparable to that of the HCl treatment. In contrast, in the case of non-diapause eggs, hatchability was decreased by DMSO in a concentration-dependent manner. The effect of DMSO was restricted within 24 hours after oviposition of diapause eggs, and the critical period was slightly shorter than the effective period of the HCl treatment. DMSO analogs, such as dimethyl formamide (DMF) and dimethyl sulfide (DMS), did little preventive effect against the diapause. Furthermore, we also investigated the permeation effects of chemical compounds by DMSO. When treated with an inhibitor of protein kinase CK2 (CK2) dissolved in DMSO, the prevention rate of the diapause was less than 40%. This means that the inhibition effect by the CK2 inhibitor was the inhibition of embryonic development after diapause prevention by DMSO. These data suggest that DMSO has the effects of preventing from entering into the diapause and permeation of chemicals into diapause eggs.
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Affiliation(s)
- Takayuki Yamamoto
- Division of Biology, College of Liberal Arts and Sciences, Kitasato University, Sagamihara, Kanagawa, Japan
| | - Keisuke Mase
- College of Humanities and Sciences, Nihon University, Setagaya-ku, Tokyo, Japan
| | - Hiroshi Sawada
- College of Humanities and Sciences, Nihon University, Setagaya-ku, Tokyo, Japan
- * E-mail:
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Liu W. Bmdelta phenotype implies involvement of Notch signaling in body segmentation and appendage development of silkworm, Bombyx mori. Arthropod Struct Dev 2013; 42:143-151. [PMID: 23142088 DOI: 10.1016/j.asd.2012.10.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2011] [Revised: 07/21/2012] [Accepted: 10/03/2012] [Indexed: 06/01/2023]
Abstract
The domesticated silkworm, Bombyx mori, belongs to the intermediate germband insects, in which the anterior segments are specified in the blastoderm, while the remaining posterior segments are sequentially generated from the cellularized growth zone. The pattern formation is distinct from Drosophila but somewhat resembles a vertebrate. Notch signaling is involved in the segmentation of vertebrates and spiders. Here, we studied the function of Notch signaling in silkworm embryogenesis via RNA interference (RNAi). Depletion of Bmdelta, the homolog of the Notch signaling ligand, led to severe defects in segment patterning, including a loss of posterior segments and irregular segment boundaries. The paired appendages on each segment were symmetrically fused along the ventral midline in Bmdelta RNAi embryos. An individual segment seemed to possess only one segmental appendage. Segmentation in prolegs could be observed. Our results show that Notch signaling is employed in not only appendage development but also body segmentation. Thus, conservation of Notch-mediated segmentation could also be extended to holometabolous insects. The involvement of Notch signaling seems to be the ancestral segmentation mechanism of arthropods.
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Affiliation(s)
- Wenbin Liu
- Department of Pharmaceutical and Biological Engineering, School of Chemical Engineering, Sichuan University, No. 24 South Section 1, Yihuan Road, Chengdu 610065, PR China.
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Sajwan S, Takasu Y, Tamura T, Uchino K, Sezutsu H, Zurovec M. Efficient disruption of endogenous Bombyx gene by TAL effector nucleases. Insect Biochem Mol Biol 2013; 43:17-23. [PMID: 23142190 DOI: 10.1016/j.ibmb.2012.10.011] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Revised: 10/18/2012] [Accepted: 10/19/2012] [Indexed: 06/01/2023]
Abstract
Engineered nucleases are proteins that are able to cleave DNA at specified sites in the genome. These proteins have recently been used for gene targeting in a number of organisms. We showed earlier that zinc finger nucleases (ZFNs) can be used for generating gene-specific mutations in Bombyx mori by an error-prone DNA repair process of non-homologous end joining (NHEJ). Here we test the utility of another type of chimeric nuclease based on bacterial TAL effector proteins in order to induce targeted mutations in silkworm DNA. We designed three TAL effector nucleases (TALENs) against the genomic locus BmBLOS2, previously targeted by ZFNs. All three TALENs were able to induce mutations in silkworm germline cells suggesting a higher success rate of this type of chimeric enzyme. The efficiency of two of the tested TALENs was slightly higher than of the successful ZFN used previously. Simple design, high frequency of candidate targeting sites and comparable efficiency of induction of NHEJ mutations make TALENs an important alternative to ZFNs.
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Affiliation(s)
- Suresh Sajwan
- Institute of Entomology, Biology Centre ASCR, and Faculty of Science, University of South Bohemia, 37005 Ceske Budejovice, Czech Republic
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Jingade AH, Srinivasa Babu GK, Lehka G, Nair CV, Ananda Rao A, Manjula A. Silkworm (Bombyx mori) cryopreservation: embryonic development as revealed by microscopic studies. Cryo Letters 2013; 34:90-99. [PMID: 23435713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Embryo cryopreservation offers a way to safeguard against unwelcome mutations and inadvertent selection that can change its unique genetic makeup. Having a genetic repository of the silkworm genetic resources would ensure preservation of original genetic makeup and will permit to study what genes may have been lost in the selection process. For cryopreservation of eggs and embryos of silkworm, the determination of embryonic stages is a prerequisite. This study reports microscopic observations on embryonic development. The embryonic stages in the dechorionated eggs were determined in parallel comparison with the embryos isolated from intact eggs of different developmental ages.
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Affiliation(s)
- A H Jingade
- Central Sericultural Germplasm Resources Centre, Tamil Nadu, India.
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36
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Masumoto M, Ohde T, Shiomi K, Yaginuma T, Niimi T. A Baculovirus immediate-early gene, ie1, promoter drives efficient expression of a transgene in both Drosophila melanogaster and Bombyx mori. PLoS One 2012; 7:e49323. [PMID: 23152896 PMCID: PMC3496687 DOI: 10.1371/journal.pone.0049323] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Accepted: 10/10/2012] [Indexed: 11/19/2022] Open
Abstract
Many promoters have been used to drive expression of heterologous transgenes in insects. One major obstacle in the study of non-model insects is the dearth of useful promoters for analysis of gene function. Here, we investigated whether the promoter of the immediate-early gene, ie1, from the Bombyx mori nucleopolyhedrovirus (BmNPV) could be used to drive efficient transgene expression in a wide variety of insects. We used a piggyBac-based vector with a 3xP3-DsRed transformation marker to generate a reporter construct; this construct was used to determine the expression patterns driven by the BmNPV ie1 promoter; we performed a detailed investigation of the promoter in transgene expression pattern in Drosophila melanogaster and in B. mori. Drosophila and Bombyx belong to different insect orders (Diptera and Lepidoptera, respectively); however, and to our surprise, ie1 promoter-driven expression was evident in several tissues (e.g., prothoracic gland, midgut, and tracheole) in both insects. Furthermore, in both species, the ie1 promoter drove expression of the reporter gene from a relatively early embryonic stage, and strong ubiquitous ie1 promoter-driven expression continued throughout the larval, pupal, and adult stages by surface observation. Therefore, we suggest that the ie1 promoter can be used as an efficient expression driver in a diverse range of insect species.
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Affiliation(s)
- Mika Masumoto
- Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya, Japan
- Division of Biology, College of Liberal Arts and Sciences, Kitasato University, Sagamihara, Kanagawa, Japan
| | - Takahiro Ohde
- Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya, Japan
| | - Kunihiro Shiomi
- Faculty of Textile Science and Technology, Shinshu University, Ueda, Nagano, Japan
| | - Toshinobu Yaginuma
- Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya, Japan
| | - Teruyuki Niimi
- Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya, Japan
- * E-mail:
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Iarygin DV, Min'kova NO, Filippovich IB. [Study of intracellular localization of the proteolytic enzyme complex and its protein inhibitors in bombyx grain]. Ontogenez 2012; 43:325-332. [PMID: 23101406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Intracellular localization of serine, cysteine and aspartate proteases, as well as their protein inhibitors, in bombyx grain in the postdiapause period of embryogenesis has been studied. Proteolytic activity of aspartate and cysteine proteases was found in lysosomal, mitochondrial, and nuclear fractions of grains. Serine protease activity was not observed in subcellular fractions of grains of the fourth day of postdiapause development. It has been shown that activities of protein inhibitors and certain peptide hydrolases in subcellular fractions provide consistent functioning and fine regulation of the proteolytic enzyme complex.
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Long DP, Zhao AC, Chen XJ, Zhang Y, Lu WJ, Guo Q, Handler AM, Xiang ZH. FLP recombinase-mediated site-specific recombination in silkworm, Bombyx mori. PLoS One 2012; 7:e40150. [PMID: 22768245 PMCID: PMC3387143 DOI: 10.1371/journal.pone.0040150] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Accepted: 06/01/2012] [Indexed: 11/18/2022] Open
Abstract
A comprehensive understanding of gene function and the production of site-specific genetically modified mutants are two major goals of genetic engineering in the post-genomic era. Although site-specific recombination systems have been powerful tools for genome manipulation of many organisms, they have not yet been established for use in the manipulation of the silkworm Bombyx mori genome. In this study, we achieved site-specific excision of a target gene at predefined chromosomal sites in the silkworm using a FLP/FRT site-specific recombination system. We first constructed two stable transgenic target silkworm strains that both contain a single copy of the transgene construct comprising a target gene expression cassette flanked by FRT sites. Using pre-blastoderm microinjection of a FLP recombinase helper expression vector, 32 G3 site-specific recombinant transgenic individuals were isolated from five of 143 broods. The average frequency of FLP recombinase-mediated site-specific excision in the two target strains genome was approximately 3.5%. This study shows that it is feasible to achieve site-specific recombination in silkworms using the FLP/FRT system. We conclude that the FLP/FRT system is a useful tool for genome manipulation in the silkworm. Furthermore, this is the first reported use of the FLP/FRT system for the genetic manipulation of a lepidopteran genome and thus provides a useful reference for the establishment of genome manipulation technologies in other lepidopteran species.
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Affiliation(s)
- Ding-Pei Long
- State Key Laboratory of Silkworm Genome Biology, Institute of Sericulture and Systems Biology, Southwest University, Chongqing, China
| | - Ai-Chun Zhao
- State Key Laboratory of Silkworm Genome Biology, Institute of Sericulture and Systems Biology, Southwest University, Chongqing, China
- * E-mail:
| | - Xue-Jiao Chen
- State Key Laboratory of Silkworm Genome Biology, Institute of Sericulture and Systems Biology, Southwest University, Chongqing, China
| | - Yang Zhang
- State Key Laboratory of Silkworm Genome Biology, Institute of Sericulture and Systems Biology, Southwest University, Chongqing, China
| | - Wei-Jian Lu
- State Key Laboratory of Silkworm Genome Biology, Institute of Sericulture and Systems Biology, Southwest University, Chongqing, China
| | - Qing Guo
- State Key Laboratory of Silkworm Genome Biology, Institute of Sericulture and Systems Biology, Southwest University, Chongqing, China
| | - Alfred M. Handler
- USDA/ARS, Center for Medical, Agricultural and Veterinary Entomology, Gainesville, Florida, United States of America
| | - Zhong-Huai Xiang
- State Key Laboratory of Silkworm Genome Biology, Institute of Sericulture and Systems Biology, Southwest University, Chongqing, China
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Xu L, Liang H, Niu Y, Wang Y, Sima Y, Xu S. Differential expression of the Bombyx mori diapause-termination timer gene Ea4 in diapause-inducing temperature and photoperiod. Arch Insect Biochem Physiol 2012; 79:182-194. [PMID: 22392803 DOI: 10.1002/arch.21019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Diapause in Bombyx mori eggs is induced by temperature and photoperiod at the stage of embryonic development in the maternal generation. In those diapause eggs, Esterase-A4 is suggested to serve as a diapause-termination timer (TIME-EA4), because its ATPase activity shows an interval-timer elevation after acid treatment or chilling of eggs to break diapause. To clarify whether the timed ATPase activity of TIME-EA4 is related to its gene (Ea4) expression, we analyzed Ea4 mRNA of eggs in diapause-inducing environmental conditions. Reverse transcription PCR (RT-PCR) analysis showed that the level of Ea4 mRNA was lower in 15DD than in 25LL (P < 0.01) or in 20LD (P < 0.01) but did not oscillate when photoperiod and temperature periodically oscillated (P > 0.05). Furthermore, expressed sequence tag profile and gene microarray analysis demonstrated that Ea4 showed stage-specific and tissue-specific expression during postembryonic stages, high Ea4 mRNA in the spinning and eclosion stages, and in integument and head, but low in gonads of fifth-instar day-3 larvae. Then we analyzed the relationship between TIME-EA4 ATPase activities and Ea4 gene expression. The ATPase activities in diapause eggs laid by the resultant adults transiently elevated after treatments to break diapause, that is, at 1.5 h after common-acid treatment and day 13 after chilling at 5°C. However, these elevations of enzyme activities were not accompanied by any increases in Ea4 mRNA levels. In conclusion, the termination of the Bombyx embryonic diapause is related to TIME-EA4 but not to its gene expression.
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Affiliation(s)
- Li Xu
- National Engineering Laboratory for Modern Silk, Department of Applied Biology, School of Biology and Basic Medical Sciences, Medical College, Soochow University, Suzhou, China
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40
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Klimenko VV, Khaoiuan' L. [Chromatin in diapause of the silkworm Bombyx mori L.: thermal parthenogenesis and normal development]. Tsitologiia 2012; 54:218-229. [PMID: 22645986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Having used hematoxylin as a stain, some features of silkworm embryo chromatin in diapause have been studied in normal and parthenogenetic development. With found direct correlation between the number of interphase chromatin grains and the number of chromosomes in the nucleus, we examined cell polyploidization in the embryo at diapause stage. Polyploidization by parthenogenesis is not reducible to endomitotic doubling of the chromosome set because it comprises 6n-nuclei. Explanation of more diverse range of polyploid cells in parthenogenesis needs to consider the fusion of cleavage nuclei that is carried out by the cytoplasmic karyogamic mechanism in the absence of fertilization. For the first time on squash preparations, in diapausing embryo, we have identified primary germ cells (PGC) that are characterized by less compact chromatin, especially in the zygotic form of development, a larger size of the nucleus and cytoplasm, and irregular number and size of nucleoli. Evaluation of PGC ploidy in parthenogenesis by calculation of "loose" chromatin grains in diapause is possible and testifies polyploidization in embryo germ-line. This explains the inevitable admixture of tetraploid eggs in diploid parthenoclone grain and its absence in normal development. Cytological method used has revealed a spiral arrangement of chromatin grains on the inner surface of the nucleus at different levels of ploidy.
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Kihara F, Niimi T, Yamashita O, Yaginuma T. Heat shock factor binds to heat shock elements upstream of heat shock protein 70a and Samui genes to confer transcriptional activity in Bombyx mori diapause eggs exposed to 5°C. Insect Biochem Mol Biol 2011; 41:843-851. [PMID: 21782023 DOI: 10.1016/j.ibmb.2011.06.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2011] [Revised: 06/23/2011] [Accepted: 06/30/2011] [Indexed: 05/31/2023]
Abstract
To understand the molecular mechanisms of how 5°C-incubation activates mRNA expression of Hsp70a and Samui genes in Bombyx mori diapause eggs, we first searched the 5'-upstream regions of the Hsp70a and Samui genes for heat shock elements (HSEs) and found two regions [Hsp70aHSE-1 (-95 to -58) and -2 (-145 to -121), and SamuiHSE-1 (-84 to -55) and -2 (-304 to -290)] corresponding to HSEs (repeats of nGAAn and/or nTTCn). We cloned four cDNAs encoding heat shock factor (HSF)-a2 (627 amino acids), -b (685 aa), -c (682 aa) and -d (705 aa), which were produced by alternative splicing. When we exposed diapause eggs to 5°C beginning at 2 day post-oviposition to break diapause, HSFd mRNA only increased after chilling for 6-8 days, a pattern very similar to those of Hsp70a and Samui mRNAs. To examine further whether HSFd binds to the respective HSEs, we carried out a gel shift assay using HSFd protein expressed in a cell-free system and the isolated HSEs; migration of the respective digoxigenin(DIG)-labeled HSE-1 and -2 of Hsp70a and Samui was retarded by addition of HSFd; the retarded bands disappeared after addition of the corresponding unlabeled HSE-1 and -2 as competitors, but were not affected by addition of the respective mutated unlabeled HSE-1 and -2. These results indicated that HSFd protein binds to the respective HSEs and may activate mRNA expression of Hsp70a and Samui genes upon exposure of diapause eggs to 5°C.
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Affiliation(s)
- Fukashi Kihara
- Laboratory of Sericulture & Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan
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Xu Y, Fu Q, Li S, He N. Silkworm egg proteins at the germ-band formation stage and a functional analysis of BmEP80 protein. Insect Biochem Mol Biol 2011; 41:572-581. [PMID: 21457781 DOI: 10.1016/j.ibmb.2011.03.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2010] [Revised: 03/06/2011] [Accepted: 03/22/2011] [Indexed: 05/30/2023]
Abstract
The patterning of embryos in early stages is a critical process for embryo development. In order to understand the molecular mechanism of early embryogenesis in silkworm, 2-DE combined with MALDI-TOF-MS technologies were used to analyze the proteins from diapause-destined eggs at the germ-band formation stage. From over 1000 spots, 93 were selected for analysis and data were obtained from 59 revealing 42 proteins. Gene Ontology annotation showed these proteins were involved in several biological processes at the germ-band formation stage, including cell stress response and protein folding, cell growth and migration, termination of diapause, and nutrition storage. Prominent among them was a new 80 kDa protein, named Bombyx mori egg protein 80 (BmEP80). BmEP80 was a component of the eggshell which was secreted by follicle cells during the late vitellogenesis stage to early choriogenesis stage (FCs -5 to +10). It disappears during early embryogenesis and RNAi against it resulted in the collapse of eggs, thus it is likely that BmEP80 is a new component of the silkworm vitelline membrane.
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Affiliation(s)
- Yunmin Xu
- The Key Sericultural Laboratory of Agricultural Ministry, College of Biotechnology, Southwest University, Tiansheng Road 1, Beibei, Chongqing 400715, China
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Gu SH, Young SC, Tsai WH, Lin JL, Lin PL. Involvement of 4E-BP phosphorylation in embryonic development of the silkworm, Bombyx mori. J Insect Physiol 2011; 57:978-985. [PMID: 21600900 DOI: 10.1016/j.jinsphys.2011.04.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Revised: 04/15/2011] [Accepted: 04/15/2011] [Indexed: 05/30/2023]
Abstract
Phosphorylation of the translational repressor 4E-binding protein (4E-BP) plays a critical role in regulating the overall translation levels in cells. In the present study, we investigated 4E-BP phosphorylation of Bombyx mori eggs by an immunoblot analysis of a conserved phospho-specific antibody to 4E-BP and demonstrated its role during embryonic development. When HCl treatment was applied to diapause-destined eggs at 20 h after oviposition, a dramatic increase in the phosphorylation of 4E-BP occurred 5 min after treatment with HCl, and high phosphorylation levels were maintained throughout embryonic stage in HCl-treated eggs compared to those in diapause (control) eggs. When HCl treatment was applied to diapause eggs on day 10 after oviposition, no dramatic activation in 4E-BP phosphorylation occurred, indicating stage-specific effects of HCl treatment. In both non-diapause eggs and eggs whose diapause had been terminated by chilling of diapausing eggs at 5°C for 70 days and then were transferred to 25°C, high phosphorylation levels of 4E-BP were also detected. Moreover, 4E-BP phosphorylation dramatically increased when dechorionated eggs were incubated in medium. The addition of rapamycin, a specific inhibitor of mammalian target of rapamycin (TOR) signaling, and LY294002, a phosphoinositide 3-kinase (PI3K) inhibitor, but not the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) kinase (MEK) inhibitor, U0126, dose-dependently inhibited 4E-BP phosphorylation in dechorionated eggs, indicating that PI3K/TOR signaling is an upstream signaling event involved in 4E-BP phosphorylation. Examination of 4E-BP gene expression levels showed no differences between treatments with HCl and water in the first hour after treatment, indicating that changes in phosphorylation of 4E-BP upon HCl treatment are mainly regulated at the post-transcriptional level. In addition, MAPK pathways and glycogen synthase kinase (GSK)-3β phosphorylation were not significantly affected in the first hour after HCl treatment. These results demonstrate that the rapid phosphorylation of 4E-BP is an early signaling event in embryonic development in the eggs whose diapause initiation was prevented by HCl treatment, thus being involved in the embryonic development of B. mori.
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Affiliation(s)
- Shi-Hong Gu
- Department of Zoology, National Museum of Natural Science, 1 Kuan-Chien Road, Taichung 404, Taiwan, ROC.
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Kawaoka S, Arai Y, Kadota K, Suzuki Y, Hara K, Sugano S, Shimizu K, Tomari Y, Shimada T, Katsuma S. Zygotic amplification of secondary piRNAs during silkworm embryogenesis. RNA 2011; 17:1401-7. [PMID: 21628432 PMCID: PMC3138575 DOI: 10.1261/rna.2709411] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2011] [Accepted: 04/28/2011] [Indexed: 05/18/2023]
Abstract
PIWI-interacting RNAs (piRNAs) are 23-30-nucleotide-long small RNAs that act as sequence-specific silencers of transposable elements in animal gonads. In flies, genetics and deep sequencing data have led to a hypothesis for piRNA biogenesis called the ping-pong cycle, where antisense primary piRNAs initiate an amplification loop to generate sense secondary piRNAs. However, to date, the process of the ping-pong cycle has never been monitored at work. Here, by large-scale profiling of piRNAs from silkworm ovary and embryos of different developmental stages, we demonstrate that maternally inherited antisense-biased piRNAs trigger acute amplification of secondary sense piRNA production in zygotes, at a time coinciding with zygotic transcription of sense transposon mRNAs. These results provide on-site evidence for the ping-pong cycle.
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MESH Headings
- Animals
- Bombyx/embryology
- Bombyx/genetics
- Cluster Analysis
- Embryo, Nonmammalian
- Embryonic Development/genetics
- Embryonic Development/physiology
- Female
- Gene Amplification/physiology
- Gene Expression Profiling
- Gene Expression Regulation, Developmental
- Microarray Analysis
- Models, Biological
- Molecular Sequence Data
- RNA, Messenger, Stored/analysis
- RNA, Messenger, Stored/genetics
- RNA, Messenger, Stored/metabolism
- RNA, Small Interfering/genetics
- RNA, Small Interfering/metabolism
- Zygote/metabolism
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Affiliation(s)
- Shinpei Kawaoka
- 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
| | - Yuji Arai
- 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
| | - Koji Kadota
- Agricultural Bioinformatics Research Unit, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Yutaka Suzuki
- Department of Medical Genome Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan
| | - Kahori Hara
- 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
| | - Sumio Sugano
- Department of Medical Genome Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan
| | - Kentaro Shimizu
- Agricultural Bioinformatics Research Unit, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Yukihide Tomari
- Institute of Molecular and Cellular Biosciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0032, Japan
- Department of Medical Genome Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0032, 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
- Agricultural Bioinformatics Research Unit, 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
- Corresponding author.E-mail .
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Xiang H, Li MW, Guo JH, Jiang JH, Huang YP. Influence of RNAi knockdown for E-complex genes on the silkworm proleg development. Arch Insect Biochem Physiol 2011; 76:1-11. [PMID: 21125568 DOI: 10.1002/arch.20393] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Larvae of many holometabolous insects possess abdominal appendages called prolegs. Lepidoptera larvae have prolegs in the segments A3-A6. Functions of Lepidoptera hox genes on these abdominal appendages development is still a controversial issue. In this article, we report the use of double strand RNA (dsRNA)-mediated interference (RNAi) to dissect the function of some hox genes, specifically E-complex genes Ubx, abd-A, and Abd-B, in the ventral appendage development of the Lepidoptera silkworm, Bombyx mori. We found that Ubx RNAi caused leg identity in A1 segment, abd-A RNAi caused severe defect of abdominal prolegs and Abd-B RNAi allowed proleg identity in more posterior abdominal segments. These results confirm that Lepidoptera hox genes Ubx and Abd-B have evolved the repressing function to ventral appendage development, which is similar to those of Drosophila. However, Lepidoptera abd-A might have been modified distinctively during evolution, and has important roles in directing the development of prolegs.
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Affiliation(s)
- H Xiang
- Shanghai Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences, Shanghai 200032, People's Republic of China
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Ponnuvel KM, Murthy GN, Awasthi AK, Rao G, Vijayaprakash NB. Differential gene expression during early embryonic development in diapause and non-diapause eggs of multivoltine silkworm Bombyx mori. Indian J Exp Biol 2010; 48:1143-1151. [PMID: 21117456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Quantification of the differential expression of metabolic enzyme and heat-shock protein genes (Hsp) during early embryogenesis in diapause and non-diapause eggs of the silkworm B. mori was carried out by semi-quantitative RT-PCR. Data analysis revealed that, the phosphofructokinase (PFK) expression started at a higher level in the early stage (6 h after oviposition) in non-diapause eggs, while in diapause induced eggs, it started at a lower level. However, the PFK gene expression in diapause eggs was comparatively higher than in non-diapause eggs. PFK facilitates use of carbohydrate reserves. The lower level of PFK gene expression in the early stage of diapause induced eggs but comparatively higher level of expression than in non-diapause eggs is due to enzyme inactivation via protein phosphorylation during early embryogenesis followed by de-phosphorylation in later stage. The sorbitol dehydrogenase-2 (SDH-2) gene was down regulated in diapause induced eggs up to 24 h and its expression levels in diapause induced eggs coincided with that of PFK gene at 48h in non-diapause eggs. During carbohydrate metabolism, there is an initial temporary accumulation of sorbitol which acts as protectant. The down regulation of SDH-2 gene during the first 24 hours in diapause induced eggs was due to the requirement of sorbitol as protectant. However, since the diapause process culminates by 48 h, the SDH-2 gene expression increased and coincided with that of PFK gene expression. The trehalase (Tre) gene expression was at a lower level in diapause induced eggs compared to non-diapausing eggs. The induction of Tre activity is to regulate uptake and use of sugar by the tissues. The non-diapause eggs revealed maximum expression of GPase gene with major fluctuations as well as an overall higher expression compared to diapause induced eggs. The diapause process requires less energy source which reflects lower activity of the gene. Heat shock protein (Hsp) genes (Hsp20.4, 40, 70, and 90) revealed differential levels of expression in both the eggs at all stages of embryonic development. The present study thus provides an overview of the differential expression levels of metabolic enzyme and Hsp genes in non-diapause and diapause induced eggs of multivoltine silkworm B. mori within 48 h after oviposition, confirming the major role of in early embryogenesis.
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Affiliation(s)
- Kangayam M Ponnuvel
- Seribiotech Research Laboratory, Carmelram Post, Kodathi, Bangalore 560 035, India.
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Li JY, Moghaddam SHH, Chen JE, Chen M, Zhong BX. Shotgun proteomic analysis on the embryos of silkworm Bombyx mori at the end of organogenesis. Insect Biochem Mol Biol 2010; 40:293-302. [PMID: 20138214 DOI: 10.1016/j.ibmb.2010.01.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2009] [Revised: 01/15/2010] [Accepted: 01/21/2010] [Indexed: 05/28/2023]
Abstract
Embryonic development of silkworm, Bombyx mori is a process of systematical expression of genes and proteins which is dominated by complex regulatory networks. To gain comprehensive insight into the molecular basis of embryonic development and its regulation mechanisms, the proteome profile of the B. mori embryos at the end of organogenesis (tubercle appearance stage, TA) was characterized using LTQ-Orbitrap mass spectrometer. Totally 963 proteins were identified with a false discovery rate (FDR) of 0.12%. They were involved in embryonic development, chemoreception, and stimuli response and so forth. The proteins with the largest number of identified unique peptides, implying their possibly higher abundance, were involved in heat shock response, lipid transport and metabolism, and apoptosis. It was consistent with the physiological status of embryo at the end of organogenesis. Many functionally important proteins were identified for the first time in B. mori embryo such as the progesterone receptor membrane component 2, antennal binding protein, sericotropin, and molting fluid carboxypeptidase A (MF-CPA). 253 (26.27%) specific proteins in TA versus labrum appearance stage (LA, four days before TA) embryos were identified, which were mainly associated with musculature, nervous system, and chemoreception system. They disclosed the differential temporal and spatial expression of proteins in the process of organogenesis. The relative mRNA levels of fifteen identified proteins in the two experimented stages were also compared using quantitative reverse transcription PCR (qRT-PCR) and showed some inconsistencies with protein expression. Gene Ontology (GO) annotation of the identified proteins showed that the most proteome representations were in the categories of "binding" and "catalytic" in molecular function, and "cellular process" and "metabolic process" in biological process.
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Affiliation(s)
- Jian-ying Li
- College of Animal Sciences, Zhejiang University, Hangzhou 310029, PR China
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Li JY, Chen X, Hosseini Moghaddam SH, Chen M, Wei H, Zhong BX. Shotgun proteomics approach to characterizing the embryonic proteome of the silkworm, Bombyx mori, at labrum appearance stage. Insect Mol Biol 2009; 18:649-660. [PMID: 19754742 DOI: 10.1111/j.1365-2583.2009.00903.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The shotgun approach has gained considerable acknowledgement in recent years as a dominant strategy in proteomics. We observed a dramatic increase of specific protein spots in two-dimensional electrophoresis (2-DE) gels of the silkworm (Bombyx mori) embryo at labrum appearance, a characteristic stage during embryonic development of silkworm which is involved with temperature increase by silkworm raiser. We employed shotgun liquid chromatography tandem mass spectrometry (LC-MS/MS) technology to analyse the proteome of B. mori embryos at this stage. A total of 2168 proteins were identified with an in-house database. Approximately 47% of them had isoelectric point (pI) values distributed theoretically in the range pI 5-7 and approximately 60% of them had molecular weights of 15-45 kDa. Furthermore, 111 proteins had an pI greater than 10 and were difficult to separate by 2-DE. Many important functional proteins related to embryonic development, stress response, DNA transcription/translation, cell growth, proliferation and differentiation, organogenesis and reproduction were identified. Among them proteins related to nervous system development were noticeable. All known heat shock proteins (HSPs) were detected in this developmental stage of B. mori embryo. In addition, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed energetic metabolism at this stage. These results were expected to provide more information for proteomic monitoring of the insect embryo and better understanding of the spatiotemporal expression of genes during embryonic developmental processes.
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Affiliation(s)
- J-Y Li
- College of Animal Sciences, Zhejiang University, Hangzhou 310029, P. R. China
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Yamamoto T, Kanekatsu M, Nakagoshi M, Kato T, Mase K, Sawada H. Casein kinase 2 during early embryonic development in silkwormBombyx mori: cDNA sequence, gene expression, and enzyme activity. ACTA ACUST UNITED AC 2009; 16:446-55. [PMID: 16287624 DOI: 10.1080/10425170500287591] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
To clarify the property of casein kinase 2 (CK2) during early embryonic development in the silkworm, we compared the phosphorylation activities of CK2 in non-diapause and diapause eggs until 60 h after oviposition. In nondiapause eggs, the phosphorylated signals were found at each stage and became progressively stronger through each stage. On the other hand, in diapause eggs, the strongest phosphorylated signals were found at approximately 12 to 24 h after oviposition and became progressively weaker through each stage. To clarify the control mechanism of these enzyme activities, we tried to clone cDNAs encoding alpha- and beta-subunit of CK2 and analyze the gene expressions. The deduced amino acid sequence of the isolated cDNAs comprised 342 and 220 residues, and these sequences showed 85-90% identities to the alpha- and beta-subunit of CK2 in Spodoptera frugiperda. RT-PCR indicated that these genes were expressed in nondiapause and diapause eggs. However, these genes expressions were not parallel with the changes in CK2 activity. These results suggest that the changes in CK2 activity are regulated mainly at the level of post-transcription during embryonic development in Bombyx mori.
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Affiliation(s)
- Takayuki Yamamoto
- Biological Laboratory, Center for Natural Science, Kitasato University, Sagamihara, Kanagawa 228-8555, Japan
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Manjunatha HB, Hosagoudar SR, Inamdar SR. Biomolecular changes and somatic mutations induced by UV laser irradiation at embryonic stage ofBombyx mori. Int J Radiat Biol 2009; 82:648-57. [PMID: 17050477 DOI: 10.1080/09553000600917241] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
PURPOSE To determine the impact of ultraviolet (UV) laser radiation on Bombyx mori embryos in terms of its effect on embryonic and larval haemolymph proteins and morphological traits. MATERIALS AND METHODS The eggs of silkworm strain NB4D2 were exposed to third harmonic laser pulses at 355 nm from a Nd:YAG laser for different durations of 30, 60, 90, 120, 150, or 180 sec. Morphological changes induced by the UV laser were analysed at larval, pupal and adult stages. The eggs exposed to UV laser irradiation at different developmental stages were subjected to protein analysis by sodium dodecyl sulfate - polyacrylamide gel electrophoresis (SDS-PAGE). The haemolymph derived from irradiated and control larva was also analysed by SDS-PAGE. RESULTS UV laser irradiation resulted in various structural polymorphisms. Asymmetrical fusion of segments was not confined to larva but persisted throughout pupal and adult stages. Development of extra caudal horn, unequal size and lack of antenna, retarded thoracic legs and variation in larval markings were observed. Comparatively, the effect of the UV laser on 8- and 16-h old embryo was greater than on the other stages. The changes in protein pattern were not distinct until the 5th day of embryogenesis as revealed by SDS-PAGE. A 178 kiloDalton (kDa) protein resolved into 198, 184 & 169 kDa polypeptides and 154 kDa new protein band along with other proteins of 110, 45, 41 & 38 kDa were noticed in irradiated eggs at the 6th day. Further, 33, 32, and 6.2 kDa new protein bands were observed in the haemolymph of 5th instar silkworm larvae derived from UV laser irradiated embryos. CONCLUSIONS A comparative analysis of the present study revealed that UV laser not only induced continuous structural polymorphisms (somatic mutations), but also induced protein changes with the appearance of new protein bands in embryonic and haemolymph protein. The UV laser could be a potential tool for biochemical genetics and genome analysis in B. mori.
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Affiliation(s)
- H B Manjunatha
- Departments of Sericulture, Laser Spectroscopy DRDO, Karnatak University, Dharwad, Karnataka, India.
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