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Tatsuke T, Tomita S. Differential expression of fibroin-related genes in middle silk glands is induced by dietary differences in a strain-dependent manner in Bombyx mori. JOURNAL OF INSECT PHYSIOLOGY 2024; 158:104695. [PMID: 39154710 DOI: 10.1016/j.jinsphys.2024.104695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2024] [Revised: 07/19/2024] [Accepted: 08/14/2024] [Indexed: 08/20/2024]
Abstract
The silkworm (Bombyx mori) is a model organism for lepidopteran insects. It is an oligophagous insect that primarily feeds on mulberry leaves and has industrial use for the production of raw silk. The development of artificial diets has provided an alternative nutrient source for silkworms; however, one significant issue is that the production of cocoons is lower in silkworms reared on artificial diets compared with those reared on mulberry leaves. The differences in the silk gland in the late-stage fifth instar silkworm larvae, when silk synthesis is most active, between those raised on artificial diets and mulberry leaves, are unknown. In this study, we identified differences in the transcriptomes of the middle and posterior silk glands of fifth instar day five silkworm larvae reared on artificial diets compared with those reared on mulberry leaves using three strains: Daizo, Nichi01, and J137 × C146. We found that the silk-related genes fibrohexamerin (fhx), fibroin-light-chain (fibL), and fibroin-heavy-chain (fibH) in the middle silk gland, and ser1 in the posterior silk gland, were differentially expressed in a strain-dependent manner. In silkworms reared on artificial diets, fhx, fibL, and fibH in the middle silk gland were upregulated in Nichi01 and downregulated in J137 × C146, whereas ser1 in the posterior silk gland was upregulated in J137 × C146 compared with silkworms reared on mulberry leaves. Our results demonstrate that the diet and strain of silkworm larvae affect the expression of genes related to silk production in their silk glands during the late fifth instar stage.
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Affiliation(s)
- Tsuneyuki Tatsuke
- Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, 1-2 Owashi, Tsukuba, Ibaraki 305-8634, Japan.
| | - Shuichiro Tomita
- Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, 1-2 Owashi, Tsukuba, Ibaraki 305-8634, Japan.
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2
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Zhang Q, Hua X, Sun Y, Lin Z, Cao Y, Zhao P, Xia Q. Dynamic chromatin conformation and accessibility changes mediate the spatial-specific gene regulatory network in Bombyx mori. Int J Biol Macromol 2023; 240:124415. [PMID: 37060980 DOI: 10.1016/j.ijbiomac.2023.124415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 04/06/2023] [Accepted: 04/07/2023] [Indexed: 04/17/2023]
Abstract
Silk gland genes of Bombyx mori can have strict spatial expression patterns, which impact their functions and silk quality; however, our understanding of their regulation mechanisms is currently insufficient. To address this, the middle silk gland (MSG) and posterior silk gland (PSG) of the silkworm were investigated. Gene ontology annotation showed that spatially specific expressed genes were involved in the formation of H3k9me and chromatin topology. Chromatin conformation data generated by Hi-C showed that the topologically associated domain boundaries around FibL and Sericin1 genes were significantly different between MSG and PSG. Changes in chromatin conformation led to changes in chromatin activity, which significantly affected the expression of nearby genes in silkworm. Chromatin accessibility regions of MSG and PSG were analyzed using FAIRE-seq, and 1006 transcription factor motifs were identified in open chromatin regions. Furthermore, the spatial-specific expression patterns of silk gland genes were mainly associated with homeobox-contained transcription factors, such as POU-M2, which was specifically bound and relatively highly expressed in the MSG. The regulatory network mediated by POU-M2 regulated most of the spatial-specific expressed genes in MSG, such as ADH1. These results can aid in improving silk performance, optimizing silkworm breeding, and improving the gene spatial regulatory model research for insects.
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Affiliation(s)
- Quan Zhang
- Biological Science Research Center, Integrative Science Center of Germplasm Creation in Western China (CHONGQING) Science City, Southwest University, 400715 Chongqing, China; Key Laboratory for Germplasm Creation in Upper Reaches of the Yangtze River, Ministry of Agriculture and Rural Affairs, 400715 Chongqing, China; Engineering Laboratory of Sericultural and Functional Genome and Biotechnology, Development and Reform Commission, 400715 Chongqing, China
| | - Xiaoting Hua
- Biological Science Research Center, Integrative Science Center of Germplasm Creation in Western China (CHONGQING) Science City, Southwest University, 400715 Chongqing, China; Key Laboratory for Germplasm Creation in Upper Reaches of the Yangtze River, Ministry of Agriculture and Rural Affairs, 400715 Chongqing, China; Engineering Laboratory of Sericultural and Functional Genome and Biotechnology, Development and Reform Commission, 400715 Chongqing, China
| | - Yueting Sun
- Biological Science Research Center, Integrative Science Center of Germplasm Creation in Western China (CHONGQING) Science City, Southwest University, 400715 Chongqing, China; Key Laboratory for Germplasm Creation in Upper Reaches of the Yangtze River, Ministry of Agriculture and Rural Affairs, 400715 Chongqing, China
| | - Zhongying Lin
- Biological Science Research Center, Integrative Science Center of Germplasm Creation in Western China (CHONGQING) Science City, Southwest University, 400715 Chongqing, China
| | - Yang Cao
- Biological Science Research Center, Integrative Science Center of Germplasm Creation in Western China (CHONGQING) Science City, Southwest University, 400715 Chongqing, China; Key Laboratory for Germplasm Creation in Upper Reaches of the Yangtze River, Ministry of Agriculture and Rural Affairs, 400715 Chongqing, China; Engineering Laboratory of Sericultural and Functional Genome and Biotechnology, Development and Reform Commission, 400715 Chongqing, China.
| | - Ping Zhao
- Biological Science Research Center, Integrative Science Center of Germplasm Creation in Western China (CHONGQING) Science City, Southwest University, 400715 Chongqing, China; Key Laboratory for Germplasm Creation in Upper Reaches of the Yangtze River, Ministry of Agriculture and Rural Affairs, 400715 Chongqing, China; Engineering Laboratory of Sericultural and Functional Genome and Biotechnology, Development and Reform Commission, 400715 Chongqing, China.
| | - Qingyou Xia
- Biological Science Research Center, Integrative Science Center of Germplasm Creation in Western China (CHONGQING) Science City, Southwest University, 400715 Chongqing, China; Key Laboratory for Germplasm Creation in Upper Reaches of the Yangtze River, Ministry of Agriculture and Rural Affairs, 400715 Chongqing, China; Engineering Laboratory of Sericultural and Functional Genome and Biotechnology, Development and Reform Commission, 400715 Chongqing, China.
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Waizumi R, Tsubota T, Jouraku A, Kuwazaki S, Yokoi K, Iizuka T, Yamamoto K, Sezutsu H. Highly accurate genome assembly of an improved high-yielding silkworm strain, Nichi01. G3 (BETHESDA, MD.) 2023; 13:jkad044. [PMID: 36814357 PMCID: PMC10085791 DOI: 10.1093/g3journal/jkad044] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 01/23/2023] [Accepted: 02/14/2023] [Indexed: 02/24/2023]
Abstract
The silkworm (Bombyx mori) is an important lepidopteran model insect and an industrial domestic animal traditionally used for silk production. Here, we report the genome assembly of an improved Japanese strain Nichi01, in which the cocoon yield is comparable to that of commercial silkworm strains. The integration of PacBio Sequel II long-read and ddRAD-seq-based high-density genetic linkage map achieved the highest quality genome assembly of silkworms to date; 22 of the 28 pseudomolecules contained telomeric repeats at both ends, and only four gaps were present in the assembly. A total of 452 Mbp of the assembly with an N50 of 16.614 Mbp covered 99.3% of the complete orthologs of the lepidopteran core genes. Although the genome sequence of Nichi01 and that of the previously reported low-yielding tropical strain p50T assured their accuracy in most regions, we corrected several regions, misassembled in p50T, in our assembly. A total of 18,397 proteins were predicted using over 95 Gb of mRNA-seq derived from 10 different organs, covering 96.9% of the complete orthologs of the lepidopteran core genes. The final assembly and annotation files are available in KAIKObase (https://kaikobase.dna.affrc.go.jp/index.html) along with a genome browser and BLAST searching service, which would facilitate further studies and the breeding of silkworms and other insects.
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Affiliation(s)
- Ryusei Waizumi
- Silkworm Research Group, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), 1-2 Owashi, Tsukuba, Ibaraki 305-8634, Japan
| | - Takuya Tsubota
- Silkworm Research Group, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), 1-2 Owashi, Tsukuba, Ibaraki 305-8634, Japan
| | - Akiya Jouraku
- Silkworm Research Group, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), 1-2 Owashi, Tsukuba, Ibaraki 305-8634, Japan
| | - Seigo Kuwazaki
- Silkworm Research Group, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), 1-2 Owashi, Tsukuba, Ibaraki 305-8634, Japan
| | - Kakeru Yokoi
- Silkworm Research Group, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), 1-2 Owashi, Tsukuba, Ibaraki 305-8634, Japan
| | - Tetsuya Iizuka
- Silkworm Research Group, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), 1-2 Owashi, Tsukuba, Ibaraki 305-8634, Japan
| | - Kimiko Yamamoto
- Silkworm Research Group, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), 1-2 Owashi, Tsukuba, Ibaraki 305-8634, Japan
| | - Hideki Sezutsu
- Silkworm Research Group, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), 1-2 Owashi, Tsukuba, Ibaraki 305-8634, Japan
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Liu H, Heng J, Wang L, Li Y, Tang X, Huang X, Xia Q, Zhao P. Homeodomain proteins POU-M2, antennapedia and abdominal-B are involved in regulation of the segment-specific expression of the clip-domain serine protease gene CLIP13 in the silkworm, Bombyx mori. INSECT SCIENCE 2022; 29:111-127. [PMID: 33860633 DOI: 10.1111/1744-7917.12916] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Revised: 02/20/2021] [Accepted: 02/26/2021] [Indexed: 06/12/2023]
Abstract
Clip-domain serine proteases (CLIPs) play important roles in insect innate immunity and development. Our previous studies indicated that CLIP13, an epidermis-specific gene, was involved in cuticle remodeling during molting and metamorphosis in the silkworm, Bombyx mori. However, the transcriptional regulatory mechanism and regulatory pathways of CLIP13 remained unclear. In the present study, we investigated CLIP13 expression and the regulation pathway controlled by 20-hydroxyecdysone (20E) in the silkworm. At the transcriptional level, expression of CLIP13 exhibited pronounced spatial and temporal specificity in different regions of the epidermis; homeodomain transcription factors POU-M2, antennapedia (Antp), and abdominal-B (Abd-B) showed similar expression change trends as CLIP13 in the head capsule, thorax, and abdomen, respectively. Furthermore, results of cell transfection assays, electrophoretic mobility shift assays, and chromatin immunoprecipitation demonstrated that POU-M2, Antp, and Abd-B were involved in the transcriptional regulation of CLIP13 by directly binding to their cis-response elements in CLIP13 promoter. RNA interference-mediated silencing of POU-M2, Antp, and Abd-B led to a decrease of CLIP13 expression in the head capsule, the epidermis of the 1st to 3rd thoracic segments and the 7th to 10th abdominal segments, respectively. Consistent with CLIP13, 20E treatment significantly upregulated expression of POU-M2, Antp, and Abd-B in the silkworm epidermis. Taken together, these data suggest that 20E positively regulates transcription of CLIP13 via homeodomain proteins POU-M2, Antp, and Abd-B in different regions of the silkworm epidermis during metamorphosis, thus affecting the molting process. Our findings provide new insight into the functions of homeodomain transcription factors in insect molting.
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Affiliation(s)
- Huawei Liu
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400716, China
- Biological Science Research Center, Southwest University, Chongqing, 400716, China
- Chongqing Key Laboratory of Sericultural Science, Chongqing Engineering and Technology Research Center for Novel Silk Materials, Southwest University, Chongqing, 400716, China
| | - Jingya Heng
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400716, China
- Biological Science Research Center, Southwest University, Chongqing, 400716, China
| | - Luoling Wang
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400716, China
| | - Youshan Li
- College of Biological Science and Engineering, Shaanxi University of Technology, Hanzhong, Shaanxi Province, 723001, China
| | - Xin Tang
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400716, China
- Biological Science Research Center, Southwest University, Chongqing, 400716, China
| | - Xuan Huang
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400716, China
- Biological Science Research Center, Southwest University, Chongqing, 400716, China
| | - Qingyou Xia
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400716, China
- Biological Science Research Center, Southwest University, Chongqing, 400716, China
- Chongqing Key Laboratory of Sericultural Science, Chongqing Engineering and Technology Research Center for Novel Silk Materials, Southwest University, Chongqing, 400716, China
| | - Ping Zhao
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400716, China
- Biological Science Research Center, Southwest University, Chongqing, 400716, China
- Chongqing Key Laboratory of Sericultural Science, Chongqing Engineering and Technology Research Center for Novel Silk Materials, Southwest University, Chongqing, 400716, China
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Masuoka Y, Cao W, Jouraku A, Sakai H, Sezutsu H, Yokoi K. Co-Expression Network and Time-Course Expression Analyses to Identify Silk Protein Regulatory Factors in Bombyx mori. INSECTS 2022; 13:insects13020131. [PMID: 35206705 PMCID: PMC8924882 DOI: 10.3390/insects13020131] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 01/25/2022] [Accepted: 01/25/2022] [Indexed: 02/04/2023]
Abstract
Simple Summary Previous studies have reported how the silk production ability of Bombyx mori can be enhanced, but the mechanism that regulates silk protein genes remains unclear. We performed co-expression network analysis using networkz, an in-house program, which led to the identification of 91 transcription factors were co-expressed with silk protein genes. Of them, 13 transcripts were identified to be novel regulatory factors by time-course expression analysis during the fifth instar larvae stage. Their expression patterns were highly relevant to those of silk protein genes. Our results suggest that the two-step expression screening was robust and highly sensitive to screen relative genes, and a complex mechanism regulates silk protein production in B. mori. The novel candidates that were identified herein can serve as key genes to develop methods to enhance the silk protein production ability of B. mori. Abstract Bombyx mori is an important economic insect and an animal model in pharmacomedical research. Although its physiology has been studied for many years, the mechanism via which silk protein genes are regulated remains unclear. In this study, we performed two-step expression screening, namely co-expression network and time-course expression analyses to screen silk protein regulation factors. A co-expression network analysis using RNA-seq data that were obtained from various tissues, including the silk glands of B. mori, was performed to identify novel silk protein regulatory factors. Overall, 91 transcription factors, including some known ones, were found to be co-expressed with silk protein genes. Furthermore, time-course expression analysis during the fifth instar larvae stage revealed that the expression pattern of 13 novel transcription factors was highly relevant to that of silk protein genes and their known regulatory factor genes. In particular, the expression peak of several transcription factors (TFs) was detected before the expression of silk protein genes peak. These results indicated that a larger number of genes than expected may be involved in silk protein regulation in B. mori. Functional analyses of function-unknown transcription factors should enhance our understanding of this system.
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Affiliation(s)
- Yudai Masuoka
- Insect Design Technology Module, Division of Insect Advanced Technology, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), 1-2 Owashi, Tsukuba 305-8634, Ibaraki, Japan;
- Research Center for Agricultural Information Technology (RCAIT), National Agriculture and Food Research Organization (NARO), 1-31-1 Kannondai, Tsukuba 305-0856, Ibaraki, Japan;
- Correspondence: (Y.M.); (K.Y.); Tel.: +81-29-838-6129 (Y.M. & K.Y.)
| | - Wei Cao
- Research Center for Agricultural Information Technology (RCAIT), National Agriculture and Food Research Organization (NARO), 1-31-1 Kannondai, Tsukuba 305-0856, Ibaraki, Japan;
| | - Akiya Jouraku
- Insect Design Technology Module, Division of Insect Advanced Technology, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), 1-2 Owashi, Tsukuba 305-8634, Ibaraki, Japan;
| | - Hiroki Sakai
- Silkworm Research Module, Division of Silk-Producing Insect Biotechnology, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), 1-2 Owashi, Tsukuba 305-8634, Ibaraki, Japan; (H.S.); (H.S.)
| | - Hideki Sezutsu
- Silkworm Research Module, Division of Silk-Producing Insect Biotechnology, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), 1-2 Owashi, Tsukuba 305-8634, Ibaraki, Japan; (H.S.); (H.S.)
| | - Kakeru Yokoi
- Insect Design Technology Module, Division of Insect Advanced Technology, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), 1-2 Owashi, Tsukuba 305-8634, Ibaraki, Japan;
- Research Center for Agricultural Information Technology (RCAIT), National Agriculture and Food Research Organization (NARO), 1-31-1 Kannondai, Tsukuba 305-0856, Ibaraki, Japan;
- Correspondence: (Y.M.); (K.Y.); Tel.: +81-29-838-6129 (Y.M. & K.Y.)
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Tsubota T, Yoshioka T, Jouraku A, Suzuki TK, Yonemura N, Yukuhiro K, Kameda T, Sezutsu H. Transcriptomic analysis of the bagworm moth silk gland reveals a number of silk genes conserved within Lepidoptera. INSECT SCIENCE 2021; 28:885-900. [PMID: 32589338 DOI: 10.1111/1744-7917.12846] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 05/25/2020] [Accepted: 06/19/2020] [Indexed: 06/11/2023]
Abstract
Lepidopteran insects produce cocoons with unique properties. The cocoons are made of silk produced in the larval tissue silk gland and our understanding of the silk genes is still very limited. Here, we investigated silk genes in the bagworm moth Eumeta variegata, a species that has recently been found to produce extraordinarily strong and tough silk. Using short-read transcriptomic analysis, we identified a partial sequence of the fibroin heavy chain gene and its product was found to have a C-terminal structure that is conserved within nonsaturniid species. This is in accordance with the presence of fibroin light chain/fibrohexamerin genes and it is suggested that the bagworm moth is producing silk composed of fibroin ternary complex. This indicates that the fibroin structure has been evolutionarily conserved longer than previously thought. Other than fibroins we identified candidates for sericin genes, expressed strongly in the middle region of the silk gland and encoding serine-rich proteins, and other silk genes, that are structurally conserved with other lepidopteran homologues. The bagworm moth is thus considered to be producing conventional lepidopteran type of silk. We further found a number of genes expressed in a specific region of the silk gland and some genes showed conserved expression with Bombyx mori counterparts. This is the first study allowing comprehensive silk gene identification and expression analysis in the lepidopteran Psychidae family and should contribute to the understanding of silk gene evolution as well as to the development of novel types of silk.
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Affiliation(s)
- Takuya Tsubota
- Institute of Agrobiological Sciences, Transgenic Silkworm Research Unit, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan
| | - Taiyo Yoshioka
- Institute of Agrobiological Sciences, Silk Materials Research Unit, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan
| | - Akiya Jouraku
- Insect Genome Research and Engineering Unit, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan
| | - Takao K Suzuki
- Institute of Agrobiological Sciences, Transgenic Silkworm Research Unit, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan
| | - Naoyuki Yonemura
- Institute of Agrobiological Sciences, Transgenic Silkworm Research Unit, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan
| | - Kenji Yukuhiro
- Institute of Agrobiological Sciences, Silk Materials Research Unit, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan
| | - Tsunenori Kameda
- Institute of Agrobiological Sciences, Silk Materials Research Unit, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan
| | - Hideki Sezutsu
- Institute of Agrobiological Sciences, Transgenic Silkworm Research Unit, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan
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Qin J, Ye F, Xu L, Zhou X, Crickmore N, Zhou X, Zhang Y, Guo Z. A cis-Acting Mutation in the PxABCG1 Promoter Is Associated with Cry1Ac Resistance in Plutella xylostella (L.). Int J Mol Sci 2021; 22:6106. [PMID: 34198929 PMCID: PMC8201282 DOI: 10.3390/ijms22116106] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 06/02/2021] [Accepted: 06/03/2021] [Indexed: 12/13/2022] Open
Abstract
The molecular mechanisms of insect resistance to Cry toxins generated from the bacterium Bacillus thuringiensis (Bt) urgently need to be elucidated to enable the improvement and sustainability of Bt-based products. Although downregulation of the expression of midgut receptor genes is a pivotal mechanism of insect resistance to Bt Cry toxins, the underlying transcriptional regulation of these genes remains elusive. Herein, we unraveled the regulatory mechanism of the downregulation of the ABC transporter gene PxABCG1 (also called Pxwhite), a functional midgut receptor of the Bt Cry1Ac toxin in Plutella xylostella. The PxABCG1 promoters of Cry1Ac-susceptible and Cry1Ac-resistant strains were cloned and analyzed, and they showed clear differences in activity. Subsequently, a dual-luciferase reporter assay, a yeast one-hybrid (Y1H) assay, and RNA interference (RNAi) experiments demonstrated that a cis-mutation in a binding site of the Hox transcription factor Antennapedia (Antp) decreased the promoter activity of the resistant strain and eliminated the binding and regulation of Antp, thereby enhancing the resistance of P. xylostella to the Cry1Ac toxin. These results advance our knowledge of the roles of cis- and trans-regulatory variations in the regulation of midgut Cry receptor genes and the evolution of Bt resistance, contributing to a more complete understanding of the Bt resistance mechanism.
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Affiliation(s)
- Jianying Qin
- Longping Branch, Graduate School of Hunan University, Changsha 410125, China; (J.Q.); (X.Z.)
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (F.Y.); (L.X.); (Y.Z.)
| | - Fan Ye
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (F.Y.); (L.X.); (Y.Z.)
| | - Linzheng Xu
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (F.Y.); (L.X.); (Y.Z.)
| | - Xuguo Zhou
- Department of Entomology, University of Kentucky, Lexington, KY 40546-0091, USA;
| | - Neil Crickmore
- School of Life Sciences, University of Sussex, Brighton BN1 9QG, UK;
| | - Xiaomao Zhou
- Longping Branch, Graduate School of Hunan University, Changsha 410125, China; (J.Q.); (X.Z.)
| | - Youjun Zhang
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (F.Y.); (L.X.); (Y.Z.)
| | - Zhaojiang Guo
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (F.Y.); (L.X.); (Y.Z.)
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Yokoi K, Tsubota T, Jouraku A, Sezutsu H, Bono H. Reference Transcriptome Data in Silkworm Bombyx mori. INSECTS 2021; 12:519. [PMID: 34205145 PMCID: PMC8228281 DOI: 10.3390/insects12060519] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 05/17/2021] [Accepted: 05/28/2021] [Indexed: 11/30/2022]
Abstract
Herein, we performed RNA-seq analysis of ten major tissues/subparts of silkworm larvae. The sequences were mapped onto the reference genome assembly and the reference transcriptome data were successfully constructed. The reference data provided a nearly complete sequence for sericin-1, a major silk gene with a complex structure. We also markedly improved the gene model for other genes. The transcriptomic expression was investigated in each tissue and a number of transcripts were identified that were exclusively expressed in tissues such as the testis. Transcripts strongly expressed in the midgut formed tight genomic clusters, suggesting that they originated from tandem gene duplication. Transcriptional factor genes expressed in specific tissues or the silk gland subparts were also identified. We successfully constructed reference transcriptome data in the silkworm and found that a number of transcripts showed unique expression profiles. These results will facilitate basic studies on the silkworm and accelerate its applications, which will contribute to further advances in lepidopteran and entomological research as well as the practical use of these insects.
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Affiliation(s)
- Kakeru Yokoi
- Insect Genome Research and Engineering Unit, Division of Applied Genetics, Institute of Agrobiological Sciences (NIAS), National Agriculture and Food Research Organization (NARO), 1-2 Owashi, Tsukuba, Ibaraki 305-8634, Japan;
- Research Center for Agricultural Information Technology (RCAIT), National Agriculture and Food Research Organization (NARO), Kintetsu Kasumigaseki Building Kasumigaseki 3-5-1, Chiyoda-ku, Tokyo 100-0013, Japan
| | - Takuya Tsubota
- Transgenic Silkworm Research Unit, Division of Biotechnology, Institute of Agrobiological Sciences (NIAS), National Agriculture and Food Research Organization (NARO), 1-2 Owashi, Tsukuba, Ibaraki 305-8634, Japan; (T.T.); (H.S.)
| | - Akiya Jouraku
- Insect Genome Research and Engineering Unit, Division of Applied Genetics, Institute of Agrobiological Sciences (NIAS), National Agriculture and Food Research Organization (NARO), 1-2 Owashi, Tsukuba, Ibaraki 305-8634, Japan;
| | - Hideki Sezutsu
- Transgenic Silkworm Research Unit, Division of Biotechnology, Institute of Agrobiological Sciences (NIAS), National Agriculture and Food Research Organization (NARO), 1-2 Owashi, Tsukuba, Ibaraki 305-8634, Japan; (T.T.); (H.S.)
| | - Hidemasa Bono
- Database Center for Life Science (DBCLS), Joint Support-Center for Data Science Research, Research Organization of Information and Systems, 1111 Yata, Mishima, Shizuoka 411-8540, Japan;
- Program of Biomedical Science, Graduate School of Integrated Sciences for Life, Hiroshima University, 3-10-23 Kagamiyama, Higashi-Hiroshima City, Hiroshima 739-0046, Japan
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9
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Kishi Y, Parker J. Cell type innovation at the tips of the animal tree. Curr Opin Genet Dev 2021; 69:112-121. [PMID: 33784538 DOI: 10.1016/j.gde.2021.01.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 01/20/2021] [Accepted: 01/24/2021] [Indexed: 11/16/2022]
Abstract
Understanding how organs originate is challenging due to the twin problems of explaining how new cell types evolve and how collective interactions between cell types arise and become selectively advantageous. Animals are assemblages of organs and cell types of different antiquities, and among the most rapidly and convergently evolving are exocrine glands and their constituent secretory cell types. Such structures have arisen independently thousands of times across the Metazoa, impacting how animals chemically interact with their environments. The recurrent evolution of exocrine systems provides a paradigm for examining how qualitative phenotypic novelties arise from variation at the cellular level. Here, we take a hierarchical perspective, focusing on the evolutionary assembly of novel biosynthetic pathways and secretory cell types, and how both selection and non-adaptive molecular processes may combine to build the complex, modular architectures of many animal glands.
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Affiliation(s)
- Yuriko Kishi
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California, 91125, United States
| | - Joseph Parker
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California, 91125, United States.
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Brückner A, Parker J. Molecular evolution of gland cell types and chemical interactions in animals. ACTA ACUST UNITED AC 2020; 223:223/Suppl_1/jeb211938. [PMID: 32034048 DOI: 10.1242/jeb.211938] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Across the Metazoa, the emergence of new ecological interactions has been enabled by the repeated evolution of exocrine glands. Specialized glands have arisen recurrently and with great frequency, even in single genera or species, transforming how animals interact with their environment through trophic resource exploitation, pheromonal communication, chemical defense and parental care. The widespread convergent evolution of animal glands implies that exocrine secretory cells are a hotspot of metazoan cell type innovation. Each evolutionary origin of a novel gland involves a process of 'gland cell type assembly': the stitching together of unique biosynthesis pathways; coordinated changes in secretory systems to enable efficient chemical release; and transcriptional deployment of these machineries into cells constituting the gland. This molecular evolutionary process influences what types of compound a given species is capable of secreting, and, consequently, the kinds of ecological interactions that species can display. Here, we discuss what is known about the evolutionary assembly of gland cell types and propose a framework for how it may happen. We posit the existence of 'terminal selector' transcription factors that program gland function via regulatory recruitment of biosynthetic enzymes and secretory proteins. We suggest ancestral enzymes are initially co-opted into the novel gland, fostering pleiotropic conflict that drives enzyme duplication. This process has yielded the observed pattern of modular, gland-specific biosynthesis pathways optimized for manufacturing specific secretions. We anticipate that single-cell technologies and gene editing methods applicable in diverse species will transform the study of animal chemical interactions, revealing how gland cell types are assembled and functionally configured at a molecular level.
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Affiliation(s)
- Adrian Brückner
- Division of Biology and Biological Engineering, California Institute of Technology, 1200 E. California Boulevard, Pasadena, CA 91125, USA
| | - Joseph Parker
- Division of Biology and Biological Engineering, California Institute of Technology, 1200 E. California Boulevard, Pasadena, CA 91125, USA
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11
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Zhang Q, Cheng T, Sun Y, Wang Y, Feng T, Li X, Liu L, Li Z, Liu C, Xia Q, He H. Synergism of open chromatin regions involved in regulating genes in Bombyx mori. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2019; 110:10-18. [PMID: 31004794 DOI: 10.1016/j.ibmb.2019.04.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 03/18/2019] [Accepted: 04/13/2019] [Indexed: 06/09/2023]
Abstract
The dynamic variability of transcription factors (TFs) and their binding sites makes it challenging to conduct genome-wide transcription regulation research. The silkworm Bombyx mori, which produces silk, is one of the most valuable model insects in the order Lepidoptera. The "opening" and "closing" of chromatin in different silk yield strains is associated with changes in silk production, making this insect a good model for studying the transcriptional regulation of genes. However, few studies have examined the open chromatin regions (OCRs) of silkworms, and studying OCR synergism and their function in silk production remains challenging. Here, we performed formaldehyde-assisted isolation of regulatory elements (FAIRE) to isolate OCRs from the silk glands of fifth-instar larvae of the DaZao and D872 strains. In total, 128,908 high confidence OCRs were identified and approximately 80% of OCRs were located in non-coding regions. OCRs upregulated adjacent genes and showed signal-dependent vulnerability to single-nucleotide polymorphisms. Mid- and low-signal OCRs were more likely to have single-nucleotide polymorphisms (SNP). Further, OCRs interacted with each other within a distance of 5 kb. We named the OCR interaction complex as the "cluster of related regions" (COREs). The functions of the CORE and its harbored OCRs showed some differences. Additionally, COREs enriched many silk protein synthesis-associated genes, some of which were upregulated. This study identified numerous high confidence regulation sites and synergistic regulatory modes of OCRs that affect adjacent genes. These results provide insight into silkworm transcriptional regulation and improve our understanding of cis-element cooperation.
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Affiliation(s)
- Quan Zhang
- Biological Science Research Center, Southwest University, Chongqing 400715, China; State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400715, China
| | - Tingcai Cheng
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400715, China; Chongqing Key Laboratory of Sericultural Science, Chongqing Engineering and Technology Research Center for Novel Silk Materials, Southwest University, Chongqing 400715, China.
| | - Yueting Sun
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400715, China
| | - Yi Wang
- Biological Science Research Center, Southwest University, Chongqing 400715, China; Chongqing Key Laboratory of Sericultural Science, Chongqing Engineering and Technology Research Center for Novel Silk Materials, Southwest University, Chongqing 400715, China
| | - Tieshan Feng
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400715, China
| | - Xiaohong Li
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400715, China
| | - Lihaoyu Liu
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400715, China
| | - Zhiqing Li
- Biological Science Research Center, Southwest University, Chongqing 400715, China; Chongqing Key Laboratory of Sericultural Science, Chongqing Engineering and Technology Research Center for Novel Silk Materials, Southwest University, Chongqing 400715, China
| | - Chun Liu
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400715, China; Chongqing Key Laboratory of Sericultural Science, Chongqing Engineering and Technology Research Center for Novel Silk Materials, Southwest University, Chongqing 400715, China
| | - Qingyou Xia
- Biological Science Research Center, Southwest University, Chongqing 400715, China; Chongqing Key Laboratory of Sericultural Science, Chongqing Engineering and Technology Research Center for Novel Silk Materials, Southwest University, Chongqing 400715, China.
| | - Huawei He
- Biological Science Research Center, Southwest University, Chongqing 400715, China; Chongqing Key Laboratory of Sericultural Science, Chongqing Engineering and Technology Research Center for Novel Silk Materials, Southwest University, Chongqing 400715, China.
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Genome-wide open chromatin regions and their effects on the regulation of silk protein genes in Bombyx mori. Sci Rep 2017; 7:12919. [PMID: 29018289 PMCID: PMC5635003 DOI: 10.1038/s41598-017-13186-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 09/19/2017] [Indexed: 11/15/2022] Open
Abstract
Nucleosome-depleted open chromatin regions (OCRs) often harbor transcription factor (TF) binding sites that are associated with active DNA regulatory elements. To investigate the regulation of silk-protein genes, DNA molecules isolated from the silk glands of third-day fifth-instar silkworm larvae and embryo-derived (BmE) cells were subjected to formal dehyde-assisted isolation of regulatory elements (FAIRE) and high-throughput sequencing. In total, 68,000 OCRs were identified, and a number of TF-binding motifs were predicted. In particular, OCRs located near silk-protein genes contained potential binding sites for functional TFs. Moreover, many TFs were found to bind to clusters of OCRs upstream of silk-protein genes, and to regulate the expression of these genes. The expression of silk protein genes may be related not only to regulating TFs (such as fkh, Bmdimm, and Bmsage), but also to developmental and hormone-induced TFs (such as zen, eve, Br, and eip74ef). Elucidation of genome-wide OCRs and their regulatory motifs in silk protein genes will provide valuable data and clues for characterizing the mechanisms of transcriptional control of silk protein genes.
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Hu W, Liu C, Cheng T, Li W, Wang N, Xia Q. Histomorphometric and transcriptomic features characterize silk glands' development during the molt to intermolt transition process in silkworm. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2016; 76:95-108. [PMID: 27395780 DOI: 10.1016/j.ibmb.2016.07.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 06/20/2016] [Accepted: 07/05/2016] [Indexed: 06/06/2023]
Abstract
The molt-intermolt cycle is an essential feature in holometabolous and hemimetabolous insects' development. In the silkworm, silk glands are under dramatic morphological and functional changes with fibroin genes' transcription being repeatedly turned off and on during the molt-intermolt cycles. However, the molecular mechanisms controlling it are still unknown. Here, silk gland's histomorphology and transcriptome analysis were used to characterize changes in its structure and gene expression patterns from molt to intermolt stages. By using section staining and transmission electron microscope, a renewable cell damage was detected in the silk gland at the molt stage, and an increased number of autophagosomes and lysosomes were found in silk gland cells' cytoplasm. Next, by using RNA sequencing, 54,578,413 reads were obtained, of which 85% were mapped to the silkworm reference genome. The expression level analysis of silk protein genes and silk gland transcription factors revealed that fibroin heavy chain, fibroin light chain, P25/fhx, sericin1, sericin3 and Dimm had consistent alteration trends in temporal expression. In addition, differentially expressed genes (DEGs) were identified, and most of the DEGs associated with ecdysone signal transduction, mRNA degradation, protein proteolysis, and autophagy were significantly down-regulated in the transition from molt to intermolt, suggesting that these pathways were activated for the silk gland renewal. These findings provide insights into the molecular mechanisms of silk gland development and silk protein genes transcriptional regulation during the molt to intermolt transition process.
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Affiliation(s)
- Wenbo Hu
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716, China
| | - Chun Liu
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716, China; Chongqing Engineering and Technology Research Center for Novel Silk Materials, Chongqing 400716, China
| | - Tingcai Cheng
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716, China
| | - Wei Li
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716, China
| | - Niannian Wang
- 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; Chongqing Engineering and Technology Research Center for Novel Silk Materials, Chongqing 400716, China.
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Takiya S, Tsubota T, Kimoto M. Regulation of Silk Genes by Hox and Homeodomain Proteins in the Terminal Differentiated Silk Gland of the Silkworm Bombyx mori. J Dev Biol 2016; 4:E19. [PMID: 29615585 PMCID: PMC5831788 DOI: 10.3390/jdb4020019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 05/08/2016] [Accepted: 05/17/2016] [Indexed: 12/15/2022] Open
Abstract
The silk gland of the silkworm Bombyx mori is a long tubular organ that is divided into several subparts along its anteroposterior (AP) axis. As a trait of terminal differentiation of the silk gland, several silk protein genes are expressed with unique regional specificities. Most of the Hox and some of the homeobox genes are also expressed in the differentiated silk gland with regional specificities. The expression patterns of Hox genes in the silk gland roughly correspond to those in embryogenesis showing "colinearity". The central Hox class protein Antennapedia (Antp) directly regulates the expression of several middle silk gland-specific silk genes, whereas the Lin-1/Isl-1/Mec3 (LIM)-homeodomain transcriptional factor Arrowhead (Awh) regulates the expression of posterior silk gland-specific genes for silk fiber proteins. We summarize our results and discuss the usefulness of the silk gland of Bombyx mori for analyzing the function of Hox genes. Further analyses of the regulatory mechanisms underlying the region-specific expression of silk genes will provide novel insights into the molecular bases for target-gene selection and regulation by Hox and homeodomain proteins.
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Affiliation(s)
- Shigeharu Takiya
- Shigeharu Takiya, Division of Biological Sciences and Center for Genome Dynamics, Faculty of Science, Hokkaido University, North 10, West 8, Kita-ku, Sapporo, Hokkaido 060-0810, Japan.
- Graduate School of Life Science, Hokkaido University, North 10, West 8, Kita-ku, Sapporo 060-0810, Japan.
| | - Takuya Tsubota
- Transgenic Silkworm Research Unit, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, 1-2 Owashi, Tsukuba, Ibaraki 305-8634, Japan.
| | - Mai Kimoto
- Graduate School of Life Science, Hokkaido University, North 10, West 8, Kita-ku, Sapporo 060-0810, Japan.
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