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Guo P, Wang Z, Shi J, Zheng H, Liu J, Hu L, Zhao P. Structural Characterization and Physiological Role of Bombyx mori Fibroinase in the Silk Gland Development. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024. [PMID: 38619539 DOI: 10.1021/acs.jafc.3c09405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
Silkworm is a highly valuable insect that produces silk through secretion by a silk gland. Within this gland, a type of cathepsin L protease called Fibroinase was identified as an enzyme for hydrolyzing the primary components of silk, including fibroin and sericin. Here, we determined the crystal structure of Fibroinase fromBombyx mori at a resolution of 1.56 Å. Comparative structural analysis revealed that Fibroinase adopted a similar structural pattern with papain-type cathepsin, consisting of an N-terminal domain and a C-terminal domain. The interface between the domains forms a substrate-binding cleft, where the E64 inhibitor noncovalently binds in a novel manner. Additionally, computational simulations combined with biochemical analysis allowed us to define the binding mode and inhibition mechanism of physiological inhibitor Bombyx cysteine protease inhibitor (BCPI) with Fibroinase. Moreover, the expression profiles and RNA interference of Fibroinase indicated its critical role in removing silk proteins in the silk gland lumen and the destruction of silk gland tissue during the larval-pupal metamorphosis. These findings enhance our understanding of the structural and biochemical features of Fibroinase and its inhibitors, while also providing evidence for the physiological role of Fibroinase in silk gland development.
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Affiliation(s)
- Pengchao Guo
- Integrative Science Center of Germplasm Creation in Western China (CHONGQING) Science City, 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 400715, China
| | - Zhan Wang
- Integrative Science Center of Germplasm Creation in Western China (CHONGQING) Science City, Biological Science Research Center, Southwest University, Chongqing 400716, China
| | - Jiaxuan Shi
- Integrative Science Center of Germplasm Creation in Western China (CHONGQING) Science City, 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 400715, China
| | - Haogang Zheng
- Integrative Science Center of Germplasm Creation in Western China (CHONGQING) Science City, 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 400715, China
| | - Jie Liu
- Integrative Science Center of Germplasm Creation in Western China (CHONGQING) Science City, 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 400715, China
| | - Lan Hu
- Integrative Science Center of Germplasm Creation in Western China (CHONGQING) Science City, 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 400715, China
| | - Ping Zhao
- Integrative Science Center of Germplasm Creation in Western China (CHONGQING) Science City, 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 400715, China
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Chen J, Guo P, Li Y, He W, Chen W, Shen Z, Zhang M, Mao J, Zhang L. Cathepsin L Contributes to Reproductive Diapause by Regulating Lipid Storage and Survival of Coccinella septempunctata (Linnaeus). Int J Mol Sci 2022; 24:ijms24010611. [PMID: 36614060 PMCID: PMC9820742 DOI: 10.3390/ijms24010611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 12/19/2022] [Accepted: 12/19/2022] [Indexed: 12/31/2022] Open
Abstract
Cathepsin L protease, which belongs to the papain-like cysteine proteases family, is an important player in many physiological and pathological processes. However, little was known about the role of cathepsin L in ladybird beetles (Coccinella septempuctata Linnaeus) during diapause. Here, we analyzed the characteristics of cathepsin L (CsCatL) in the females of C. septempunctata and its role during the diapause of the ladybeetle. CsCatL was cloned and identified from beetle specimens by rapid amplification of cDNA-ends (RACE). The cDNA sequence of CsCatL was 971 bp in length, including an 843 bp open reading frame encoding a protein of 280 amino acids. It was identified as the cathepsin L group by phylogenetic analysis. Knockdown of CsCatL by RNA interference led to decreased expression levels of fatty acid synthase 2 (fas 2) genes and suppressed lipid accumulation. Furthermore, silencing the CsCatL gene distinctly reduced diapause-related features and the survival of female C. spetempunctata under diapause-inducing conditions. The results suggested that the CsCatL gene was involved in fatty acid biosynthesis and played a crucial role in the survival of adult C. septempunctata during the diapause preparation stage.
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Qin S, Sun L, Zhang S, Sun X, Li M. BmAbl1 Regulates Silk Protein Synthesis via Glutathione Metabolism in Bombyx mori. INSECTS 2022; 13:967. [PMID: 36354792 PMCID: PMC9696079 DOI: 10.3390/insects13110967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 10/19/2022] [Accepted: 10/19/2022] [Indexed: 06/16/2023]
Abstract
Bombyx mori, domesticated from wild silkworms, is an economic insect that feeds on mulberry leaves and produces silk. In the current study, we demonstrated the contribution of BmAbl1 in silk protein synthesis. The inhibition and knockout of BmAbl1 can reduce the larva weight and CSW. The effect on CSW of BmAbl1 is not on the transcriptional level, but on the translational level. RNA-sequencing data suggested that amino acid synthesis and the metabolism process had a great difference between the BmAbl1- and Control strain, particularly glutathione metabolism. An abnormality in glutathione metabolism led to the reduction of free glycine and serine content, which are the main components of fibroin protein. Finally, fibroin protein synthesis has been reduced, including fibroin-heavy chain, fibroin-light chain, and p25 protein. This finding brought to light the role of BmAbl1 in the silk protein synthesis process.
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Affiliation(s)
- Sheng Qin
- Jiangsu Key Laboratory of Sericultural Biology and Biotechnology, School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang 212100, China
- Key Laboratory of Silkworm and Mulberry Genetic Improvement, Ministry of Agriculture and Rural Affairs, Sericultural Research Institute, Chinese Academy of Agricultural Science, Zhenjiang 212100, China
| | - Lingling Sun
- Jiangsu Key Laboratory of Sericultural Biology and Biotechnology, School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang 212100, China
| | - Shu Zhang
- Jiangsu Key Laboratory of Sericultural Biology and Biotechnology, School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang 212100, China
| | - Xia Sun
- Jiangsu Key Laboratory of Sericultural Biology and Biotechnology, School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang 212100, China
- Key Laboratory of Silkworm and Mulberry Genetic Improvement, Ministry of Agriculture and Rural Affairs, Sericultural Research Institute, Chinese Academy of Agricultural Science, Zhenjiang 212100, China
| | - Muwang Li
- Jiangsu Key Laboratory of Sericultural Biology and Biotechnology, School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang 212100, China
- Key Laboratory of Silkworm and Mulberry Genetic Improvement, Ministry of Agriculture and Rural Affairs, Sericultural Research Institute, Chinese Academy of Agricultural Science, Zhenjiang 212100, China
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Molecular Characterization of the Functional Genes Associated with Silk Assembly, Transport, and Protection in the Silk Glands of Popular Multivoltine Breeds of Silkworm Bombyx mori. L. Appl Biochem Biotechnol 2022; 195:2371-2394. [PMID: 36149583 DOI: 10.1007/s12010-022-04158-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/28/2022] [Indexed: 11/02/2022]
Abstract
Bombyx mori is an agriculturally important insect used extensively for silk production. India, especially the eastern regions, is mostly dependent on the multivoltine breeds of silkworm Bombyx mori and their hybrids/crossbreeds. The multivoltine breeds are indigenous and superior in survival and hardiness but are relatively inferior in terms of qualitative traits, typically the silk quality. Therefore, it is highly relevant to understand the mechanism of silk production in the multivoltine breeds to decipher the reasons for the inferior quality of silk produced by the multivoltine breeds and thus gain leads to improve the quality of silk production in multivoltine breeds. With this background, study was carried to identify differential expression of the major genes associated with silk proteins in the silk gland region of the popular multivoltine breeds. Our results indicated that although fib-L, fib-H, Sericins, and P25 are the major genes associated with silk filament, a few other genes associated with silk assembly, transport, and protection in the silk glands are the ones that largely contribute towards efficient silk production. The differential expression of these genes had a major effect on the movement of silk proteins within the silk gland and the efficiency of silk production as well. The Pearson correlation revealed a positive correlation amongst the genes dealt with in this study, indicating that the concurrent increase in expression of both the types of genes in the silk glands, significantly improves the silk production.
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Ye X, Tang X, Zhao S, Ruan J, Wu M, Wang X, Li H, Zhong B. Mechanism of the growth and development of the posterior silk gland and silk secretion revealed by mutation of the fibroin light chain in silkworm. Int J Biol Macromol 2021; 188:375-384. [PMID: 34371049 DOI: 10.1016/j.ijbiomac.2021.08.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 07/12/2021] [Accepted: 08/02/2021] [Indexed: 10/20/2022]
Abstract
Silkworm, as a model organism, has very high economic value due to its silk secretion ability. Although a large number of studies have attempted to elucidate the mechanism of silk secretion, it remains unclear. In this study, the fibroin light chain (Fib-L) gene of silkworm was subjected to CRISPR/Cas9 editing, which yielded premature termination of translation at 135 aa. Compared with those of the wild type, the posterior silk glands (PSGs) of the homozygous mutants on the third day of the fifth instar showed obvious premature degeneration. Comparative transcriptome and proteomic analyses of the PSGs of wild-type individuals, heterozygous mutants and homozygous mutants were performed on the fourth day of the fifth instar. A GO enrichment analysis showed that the differentially expressed genes (DEGs) between homozygous mutants and wild-type individuals were enriched in cytoskeleton-related terms, and a KEGG enrichment analysis showed that the upregulated DEGs between homozygous mutants and wild-type individuals were enriched in the phagosome and apoptosis pathways. These results indicated that apoptosis was activated prematurely in the PSGs of homozygous mutants. Furthermore, autophagy and heat shock response were activated in the PSGs of homozygous mutants, as demonstrated by an analysis of the DEGs related to autophagy and heat shock. A comparative proteomic analysis further confirmed that autophagy, apoptosis and the heat shock response were activated in the PSGs of homozygous mutants, which led to premature degradation of the PSGs. These results provide insights for obtaining a more in-depth understanding of the mechanism of silk secretion in silkworms.
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Affiliation(s)
- Xiaogang Ye
- College of Animal Sciences, Zhejiang University, Hangzhou, PR China
| | - Xiaoli Tang
- College of Animal Sciences, Zhejiang University, Hangzhou, PR China
| | - Shuo Zhao
- College of Animal Sciences, Zhejiang University, Hangzhou, PR China
| | - Jinghua Ruan
- College of Animal Sciences, Zhejiang University, Hangzhou, PR China
| | - Meiyu Wu
- College of Animal Sciences, Zhejiang University, Hangzhou, PR China
| | - Xiaoxiao Wang
- College of Animal Sciences, Zhejiang University, Hangzhou, PR China
| | - Huiping Li
- College of Animal Sciences, Zhejiang University, Hangzhou, PR China
| | - Boxiong Zhong
- College of Animal Sciences, Zhejiang University, Hangzhou, PR China.
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Yang H, Zhang R, Zhang Y, Liu Q, Li Y, Gong J, Hou Y. Cathepsin-L is involved in degradation of fat body and programmed cell death in Bombyx mori. Gene 2020; 760:144998. [DOI: 10.1016/j.gene.2020.144998] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 07/16/2020] [Accepted: 07/21/2020] [Indexed: 12/25/2022]
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Guo P, Wang Z, Wang Q, Liu H, Zhang Y, Xu H, Zhao P. Fibroinase and its physiological inhibitors involved in the regulation of silk gland development in the silkworm, Bombyx mori. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2019; 106:19-27. [PMID: 30639702 DOI: 10.1016/j.ibmb.2019.01.003] [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: 10/16/2018] [Revised: 12/22/2018] [Accepted: 01/09/2019] [Indexed: 06/09/2023]
Abstract
Fibroinase, a cathepsin L-like cysteine protease, was previously identified in the silk gland of the silkworm, Bombyx mori. It shows high degradation activity during the pre-pupa period, when the silk gland undergoes apoptosis and remodeling. Here, we recombinantly expressed pro-fibroinase and activated it in vitro. Fibroinase showed optimal hydrolytic activity at pH 4.0 and its optimum temperature was about 42 °C. One physiological inhibitor, B. mori cysteine protease inhibitor (BCPI) was found, which showed strong inhibitory activity against fibroinase. The inhibitory reaction was caused by the formation of a non-covalent complex; this is in contrast to a previously reported mode of fibroinase inhibition by Serpin18. Expression profiles and immunolocalization analysis demonstrated that fibroinase was involved in silk gland development by degrading silk proteins and apoptosis/remodeling of silk glands at specific points. Furthermore, the comparison of the temporal expression of fibroinase and its inhibitors, BCPI and Serpin18, indicated that these inhibitors were involved in the silk gland development by regulating the activity of fibroinase from the fifth instar until the early spinning stage. These findings improve our understanding of the mechanism of protease regulation and its inhibitors in silk gland development.
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Affiliation(s)
- Pengchao Guo
- 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
| | - Zhan Wang
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400715, China
| | - Qian Wang
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400715, China
| | - Huawei Liu
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400715, China
| | - Yunshi Zhang
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400715, China
| | - Haiyang Xu
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400715, China
| | - Ping Zhao
- 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.
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Guo SY, Wu WM, Li SY, Liu Y, Ruan ZF, Ye MQ, Xiao Y, Zhong YJ, Cao Y, Li K, Tian L. 20-Hydroxyecdysone-upregulated proteases involved in Bombyx larval fat body destruction. INSECT MOLECULAR BIOLOGY 2018; 27:724-738. [PMID: 29888823 DOI: 10.1111/imb.12511] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
During insect larval-pupal metamorphosis, the obsolete larval organs and tissues undergo histolysis and programmed cell death to recycle cellular materials. It has been demonstrated that some cathepsins are essential for histolysis in larval tissues, but the process of tissue destruction is not well documented. Fat body, the homologous organ to mammalian liver and adipose tissue, goes through a distinct destruction process during larval-pupal transition. Herein, we found that most of the Bombyx proteases - including Bombyx cathepsin B (BmCatB) (BmCatLL-2), Bombyx cathepsin D (BmCatD), Bombyx cathepsin L like-1 (BmCatLL-1) and -2(BmCatLL-2), Bombyx fibroinase (BmBcp), Bombyx matrix metalloprotease (BmMmp), Bombyx A disintegrin and metalloproteinase with thrombospondin motifs 1 (BmAdamTS-1), Bombyx A disintegrin and metalloproteinase with thrombospondin motifs like (BmAdamTS L) and Bombyx cysteine protease inhibitor (Bmbcpi)- were expressed highly in fat body during feeding and metamorphosis, with a peak occurring during the nonfeeding moulting or prepupal stage, as well as being responsive to 20-hydroxyecdysone (20E). The aforementioned protease genes expression was upregulated by injection of 20E into the feeding larvae, while blocking 20E signalling transduction led to downregulation. Western blotting and immunofluorescent staining of BmCatB and BmBcp confirmed the coincident variation of their messenger RNA (mRNA) and protein level during the development and after the treatments. Moreover, BmCatB, BmBcp, BmMmp and BmAdamTS-1 RNA interference all led to blockage of larval fat body destruction. Taken together, we conclude that 20E regulates larval fat body destruction by upregulating related protease gene expression and protein levels during larval-pupal transition.
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Affiliation(s)
- S-Y Guo
- Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding/Guangdong Provincial Sericulture and Mulberry Engineering Research Center, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - W-M Wu
- Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding/Guangdong Provincial Sericulture and Mulberry Engineering Research Center, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - S-Y Li
- Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding/Guangdong Provincial Sericulture and Mulberry Engineering Research Center, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Y Liu
- Shanghai Generay Biotech Co. Ltd, Shanghai, China
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Z F Ruan
- Guangzhou Key Laboratory of Insect Development Regulation and Application Research, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, China
| | - M-Q Ye
- The Sericultural and Agri-Food Research Institute of the Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Y Xiao
- Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding/Guangdong Provincial Sericulture and Mulberry Engineering Research Center, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Y-J Zhong
- Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding/Guangdong Provincial Sericulture and Mulberry Engineering Research Center, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Y Cao
- Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding/Guangdong Provincial Sericulture and Mulberry Engineering Research Center, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - K Li
- Guangzhou Key Laboratory of Insect Development Regulation and Application Research, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, China
| | - L Tian
- Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding/Guangdong Provincial Sericulture and Mulberry Engineering Research Center, College of Animal Science, South China Agricultural University, Guangzhou, China
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Yang H, Li J, Liu Q, Zhang Z, Gong J, Hou Y. Purification and characterization of two cysteine proteinase inhibitors from silkworm, Bombyx mori. Biochem Biophys Res Commun 2018; 503:3108-3113. [PMID: 30144976 DOI: 10.1016/j.bbrc.2018.08.100] [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: 08/06/2018] [Accepted: 08/14/2018] [Indexed: 10/28/2022]
Abstract
Cysteine proteinase inhibitors from silkworm are selective inhibitors with low molecular weight and regulate cathepsin L-like cysteine proteinase activity, thus, affecting silkworm metamorphosis. In a previous study, two cysteine proteinase inhibitors, BCPI and BmCPI, were identified in the silkworm genome. To characterize these inhibitors, we expressed and purified them in an Escherichia coli system and analyzed their structure and inhibitory activity in vitro. Both inhibitors showed strong tolerance to high temperature. Their CD spectra revealed that their secondary structures could be recovered by a gradual decrease in temperature. Compared to BCPI, BmCPI exhibited weak inhibitory activity toward cathepsin L. BCPI activity was significantly decreased when its C-terminus was truncated, whereas BmCPI activity increased considerably when the C-terminus tail of BCPI was attached to BmCPI. Additionally, the inhibitory activity of BCPI was strongly reduced if R31 was mutated to A31. In summary, two cysteine proteinase inhibitors from silkworm were characterized in the present study, which facilitates an understanding of the interaction mechanism between cysteine proteinase and its inhibitors in the silkworm.
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Affiliation(s)
- Huan Yang
- State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University, Chongqing, Beibei, Chongqing 400715, China
| | - Jianwei Li
- State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University, Chongqing, Beibei, Chongqing 400715, China
| | - Qing Liu
- State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University, Chongqing, Beibei, Chongqing 400715, China
| | - Ziyu Zhang
- State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University, Chongqing, Beibei, Chongqing 400715, China
| | - Jing Gong
- State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University, Chongqing, Beibei, Chongqing 400715, China
| | - Yong Hou
- State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University, Chongqing, Beibei, Chongqing 400715, China; Chongqing Key Laboratory for Sericultural Science, Southwest University, Beibei, Chongqing 400715, China.
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Tian S, Zhang Z, Zhang R, Liu Q, Xu S, Gong J, Hou Y. Analysis of cysteine protease inhibitor gene (BmCPI) promoter activity in silkworms using bac-to-bac baculovirus systems. Biosci Biotechnol Biochem 2018; 82:1488-1496. [DOI: 10.1080/09168451.2018.1485478] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
ABSTRACT
A cysteine protease inhibitor of Bombyx mori (BmCPI) plays an important role in pupation, molting, and dissociation of tissues. The present study identified and analyzed the BmCPI promoter region to better understand its functional regulatory mechanisms. Eight promoter fragments of different lengths were analyzed using an improved Bac-to-Bac expression system. Luciferase activities were investigated both in BmE cells and larval organisms after infection with the Bac-to-Bac system, and similar changes in activity were observed in both models. Strong activity was detected in the longest promoter (2005 bp, −1969 to +36), and activity changed significantly with truncation of promoter length. An electrophoretic mobility shift assay showed that the promoter region from −32 to +6 bp played a critical role in activating the downstream gene promoter element, where some potential elements were also predicted by informatics tools. The findings offer a basic reference for the mechanism of transcriptional regulation of BmCPI.
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Affiliation(s)
- Sha Tian
- State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University, Beibei, Chongqing China
| | - Ziyu Zhang
- State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University, Beibei, Chongqing China
| | - Renze Zhang
- State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University, Beibei, Chongqing China
| | - Qing Liu
- State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University, Beibei, Chongqing China
| | - Shuping Xu
- State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University, Beibei, Chongqing China
| | - Jing Gong
- State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University, Beibei, Chongqing China
| | - Yong Hou
- State Key Laboratory of Silkworm Genome Biology, College of Biotechnology, Southwest University, Beibei, Chongqing China
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Ma L, Li K, Guo Y, Sun X, Deng H, Li K, Feng Q, Li S. Ras-Raf-MAPK signaling promotes nuclear localization of FOXA transcription factor SGF1 via Ser91 phosphorylation. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2018; 1865:560-571. [PMID: 29355586 DOI: 10.1016/j.bbamcr.2018.01.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 01/11/2018] [Accepted: 01/14/2018] [Indexed: 01/27/2023]
Abstract
Ras-Raf-MAPK signaling promotes cell proliferation and cell survival. We previously reported that Ras1CA overexpression, specifically in the posterior silk glands (PSGs) of the silkworm Bombyx mori, increased fibroin synthesis and cell size, resulting in improved silk yields. In this study, we compared the iTRAQ-based phosphoproteomic profiles of PSGs from wild-type and Ras1CA-overexpressing silkworms. Silk gland factor 1 (SGF1), a FOXA transcription factor that plays a critical role in activating fibroin gene expression, was identified as a phosphoprotein harboring Ser91 as a potential MAPK phosphorylation site. Ser91 phosphorylation of SGF1 was enhanced by Ras1CA overexpression, and this finding was verified by selected reaction monitoring. Consistently, MAPK activity is well correlated with Ser91 phosphorylation of SGF1 and its nuclear localization in PSG cells during silkworm development. Ras1CA overexpression and treatment with inhibitors of Ras signaling promoted or inhibited SGF1 nuclear localization, respectively; mutation of Ser91 to Ala91 eliminated SGF1 nuclear localization. Moreover, MAPK binds to SGF1 and directly phosphorylates Ser91, demonstrating Ser91 as a MAPK phosphorylation site in SGF1. In conclusion, Ras-Raf-MAPK signaling promotes SGF1 nuclear localization for transactivation via Ser91 phosphorylation in silkworms, showing that FOXA transcription factors are regulated via MAPK phosphorylation in animals.
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Affiliation(s)
- Li Ma
- Guangzhou Key Laboratory of Insect Development Regulation and Application Research, Institute of Insect Science and Technology & School of Life Sciences, South China Normal University, Guangzhou 510631, China; Department of Neonatology, Shanghai Children's Hospital, Shanghai Jiao Tong University, Shanghai 200062, 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
| | - Kang Li
- Guangzhou Key Laboratory of Insect Development Regulation and Application Research, Institute of Insect Science and Technology & School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Yaxin Guo
- 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; School of Life Science, East China Normal University, Shanghai 200241, China
| | - Xiang Sun
- Guangzhou Key Laboratory of Insect Development Regulation and Application Research, Institute of Insect Science and Technology & School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Huimin Deng
- Guangzhou Key Laboratory of Insect Development Regulation and Application Research, Institute of Insect Science and Technology & School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Kai Li
- School of Life Science, East China Normal University, Shanghai 200241, China
| | - Qili Feng
- Guangzhou Key Laboratory of Insect Development Regulation and Application Research, Institute of Insect Science and Technology & School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Sheng Li
- Guangzhou Key Laboratory of Insect Development Regulation and Application Research, Institute of Insect Science and Technology & School of Life Sciences, South China Normal University, Guangzhou 510631, 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.
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Zhang P, Liu S, Song HS, Zhang G, Jia Q, Li S. Yorkie CA overexpression in the posterior silk gland improves silk yield in Bombyx mori. JOURNAL OF INSECT PHYSIOLOGY 2017; 100:93-99. [PMID: 28583832 DOI: 10.1016/j.jinsphys.2017.06.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 06/01/2017] [Accepted: 06/01/2017] [Indexed: 06/07/2023]
Abstract
The traditional hybrid breeding techniques can no longer meet the increasing demands for silk production by the silkworm, Bombyx mori, and further improvement of the silk yield will depend on modern molecular breeding techniques. Here, we report improved silk yield in transgenic silkworms overexpressing the oncogene YorkieCA specifically in the posterior silk gland (PSG). The YorkieCA cDNA was ligated downstream of the hr3 enhancer and the fibroin L-chain (Fil) promoter, then inserted into a piggyBac vector for transgene. Overexpression of YorkieCA in the PSG significantly increased the weight of the PSG, and also increased the weight of the cocoon, larval body, and pupal body to decreasing degrees. Overexpression of YorkieCA up-regulated the Yorkie target genes resulting in increased cell size, endomitosis, the number of protein synthesis organelles, the expression of fibroin genes in the PSG, and eventually silk yield. Additionally, as we reported previously using the binary GAL4/UAS system, transgenic silkworms overexpressing Ras1CA with the hr3 enhancer and the Fil promoter also showed improved silk yield. Unfortunately, the hybrid progeny of YorkieCA-overexpressing silkworms and Ras1CA-overexpressing silkworms did not show overlapping improved silk yield due to the failure to increase expression of both Yorkie and Ras1.
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Affiliation(s)
- Panli Zhang
- College of Life Sciences, Shanghai University, Shanghai 200444, China
| | - Shumin Liu
- 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
| | - Hong-Sheng Song
- College of Life Sciences, Shanghai University, Shanghai 200444, China
| | - Guozheng Zhang
- College of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212018, China
| | - Qiangqiang Jia
- Guangzhou Key Laboratory of Insect Development Regulation and Application Research, Institute of Insect Sciences and School of Life Sciences, South China Normal University, Guangzhou 510631, China.
| | - Sheng Li
- Guangzhou Key Laboratory of Insect Development Regulation and Application Research, Institute of Insect Sciences and School of Life Sciences, South China Normal University, Guangzhou 510631, China.
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13
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Liu S, Zhang P, Song HS, Qi HS, Wei ZJ, Zhang G, Zhan S, Liu Z, Li S. Yorkie Facilitates Organ Growth and Metamorphosis in Bombyx. Int J Biol Sci 2016; 12:917-30. [PMID: 27489496 PMCID: PMC4971731 DOI: 10.7150/ijbs.14872] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2016] [Accepted: 05/06/2016] [Indexed: 01/15/2023] Open
Abstract
The Hippo pathway, which was identified from genetic screens in the fruit fly, Drosophila melanogaster, has a major size-control function in animals. All key components of the Hippo pathway, including the transcriptional coactivator Yorkie that is the most critical substrate and downstream effector of the Hippo kinase cassette, are found in the silkworm, Bombyx mori. As revealed by microarray and quantitative real-time PCR, expression of Hippo pathway genes is particularly enriched in several mitotic tissues, including the ovary, testis, and wing disc. Developmental profiles of Hippo pathway genes are generally similar (with the exception of Yorkie) within each organ, but vary greatly in different tissues showing nearly opposing expression patterns in the wing disc and the posterior silk gland (PSG) on day 2 of the prepupal stage. Importantly, the reduction of Yorkie expression by RNAi downregulated Yorkie target genes in the ovary, decreased egg number, and delayed larval-pupal-adult metamorphosis. In contrast, baculovirus-mediated Yorkie(CA) overexpression upregulated Yorkie target genes in the PSG, increased PSG size, and accelerated larval-pupal metamorphosis. Together the results show that Yorkie potentially facilitates organ growth and metamorphosis, and suggest that the evolutionarily conserved Hippo pathway is critical for size control, particularly for PSG growth, in the silkworm.
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Affiliation(s)
- Shumin Liu
- 1. 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
| | - Panli Zhang
- 1. 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; 2. College of Life Sciences, Shanghai University, Shanghai 200444, China
| | - Hong-Sheng Song
- 2. College of Life Sciences, Shanghai University, Shanghai 200444, China
| | - Hai-Sheng Qi
- 3. School of Biotechnology and Food Engineering, Hefei University of Technology, Hefei 230009, China
| | - Zhao-Jun Wei
- 3. School of Biotechnology and Food Engineering, Hefei University of Technology, Hefei 230009, China
| | - Guozheng Zhang
- 4. College of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang Jiangsu 212018, China
| | - Shuai Zhan
- 1. 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
| | - Zhihong Liu
- 5. Epartment of Urology, Shanghai General Hospital, Medical School of Shanghai Jiao Tong University, Shanghai 200080, China
| | - Sheng Li
- 1. 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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14
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Zhang W, Wang J, Zhang C, Fang Q, Shu J, Li S, Jin J, Wang D, Nie Z, Lv Z, Zhang Y. Synergetic Protein Factors That Improve rhGM-CSF Absorption via an Oral Route Exist in Silkworm Pupae. Mol Pharm 2015; 12:1347-55. [PMID: 25775407 DOI: 10.1021/mp500371g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Recent studies have demonstrated that recombinant human granulocyte macrophage colony-stimulating factor (rhGM-CSF) produced by the silkworm pupae bioreactor is absorbed into blood through oral administration and functions as an active cytokine. The aim of this study was to further examine and identify synergetic protein factors in silkworm pupae that improve rhGM-CSF absorption via an oral route. The concentrations of rhGM-CSF in serum were evaluated in mice after oral administration of rhGM-CSF using different chemical compositions of silkworm pupae as pharmaceutical excipients. The experimental data revealed that the supernatant lyophilized powder (SLP) of a homogenized slurry of silkworm pupae caused a significant increase in the rhGM-CSF level in blood when rhGM-CSF was orally administered with SLP, suggesting that synergetic protein factors that improve the oral absorption of rhGM-CSF primarily exist in SLP. As shown by scanning electron microscopy, microspheres were formed when rhGM-CSF was coated with SLP. Animal experimental data showed that the absorption of orally administered rhGM-CSF through the gastrointestinal (GI) tract primarily resulted from protein factors present in the SLP retentate obtained after 10 kDa ultrafiltration. Surface plasmon resonance spectroscopy analysis demonstrated that several protein factors present in the SLP retentate obtained after 10 kDa ultrafiltration were bound to rhGM-CSF. Proteins bound to rhGM-CSF by liquid chromatography-mass spectrometry were identified as chymotrypsin inhibitor SCI-II precursor, cationic peptide CP8 precursor, Kazal-type proteinase inhibitor, and chymotrypsin inhibitor SCI-I. These findings indicate that these proteinase inhibitors play an important role in improving rhGM-CSF absorption in the GI tract.
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Affiliation(s)
- Wenping Zhang
- Institute of Biochemistry, College of Life Science, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Jian Wang
- Institute of Biochemistry, College of Life Science, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Chen Zhang
- Institute of Biochemistry, College of Life Science, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Qiang Fang
- Institute of Biochemistry, College of Life Science, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Jianhong Shu
- Institute of Biochemistry, College of Life Science, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Si Li
- Institute of Biochemistry, College of Life Science, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Jia Jin
- Institute of Biochemistry, College of Life Science, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Dan Wang
- Institute of Biochemistry, College of Life Science, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Zuoming Nie
- Institute of Biochemistry, College of Life Science, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Zhengbing Lv
- Institute of Biochemistry, College of Life Science, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Yaozhou Zhang
- Institute of Biochemistry, College of Life Science, Zhejiang Sci-Tech University, Hangzhou 310018, China
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Fang SM, Hu BL, Zhou QZ, Yu QY, Zhang Z. Comparative analysis of the silk gland transcriptomes between the domestic and wild silkworms. BMC Genomics 2015; 16:60. [PMID: 25887670 PMCID: PMC4328555 DOI: 10.1186/s12864-015-1287-9] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 01/26/2015] [Indexed: 12/21/2022] Open
Abstract
Background Bombyx mori was domesticated from the Chinese wild silkworm, Bombyx mandarina. Wild and domestic silkworms are good models in which to investigate genes related to silk protein synthesis that may be differentially expressed in silk glands, because their silk productions are very different. Here we used the mRNA deep sequencing (RNA-seq) approach to identify the differentially expressed genes (DEGs) in the transcriptomes of the median/posterior silk glands of two domestic and two wild silkworms. Results The results indicated that about 58% of the total genes were expressed (reads per kilo bases per million reads (RPKM) ≥ 1) in each silkworm. Comparisons of the domestic and wild silkworm transcriptomes revealed 32 DEGs, of which 16 were up-regulated in the domestic silkworms compared with in the wild silkworms, and the other 16 were up-regulated in the wild silkworms compared with in the domestic silkworms. Quantitative real-time polymerase chain reaction (qPCR) was performed for 15 randomly selected DEGs in domestic versus wild silkworms. The qPCR results were mostly consistent with the expression levels determined from the RNA-seq data. Based on a Gene Ontology (GO) enrichment analysis and manual annotation, five of the up-regulated DEGs in the wild silkworms were predicted to be involved in immune response, and seven of the up-regulated DEGs were related to the GO term “oxidoreductase activity”, which is associated with antioxidant systems. In the domestic silkworms, the up-regulated DEGs were related mainly to tissue development, secretion of proteins and metabolism. Conclusions The up-regulated DEGs in the two domestic silkworms may be involved mainly in the highly efficient biosynthesis and secretion of silk proteins, while the up-regulated DEGs in the two wild silkworms may play more important roles in tolerance to pathogens and environment adaptation. Our results provide a foundation for understanding the molecular mechanisms of the silk production difference between domestic and wild silkworms. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-1287-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Shou-Min Fang
- School of Life Sciences, Chongqing University, Chongqing, 400044, China. .,College of Life Science, China West Normal University, Nanchong, 637002, China.
| | - Bi-Li Hu
- Key Sericultural Laboratory of Shaanxi, Ankang University, Ankang, 725000, China.
| | - Qiu-Zhong Zhou
- School of Life Sciences, Chongqing University, Chongqing, 400044, China.
| | - Quan-You Yu
- School of Life Sciences, Chongqing University, Chongqing, 400044, China.
| | - Ze Zhang
- School of Life Sciences, Chongqing University, Chongqing, 400044, China.
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16
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Jin S, Cheng T, Jiang L, Lin P, Yang Q, Xiao Y, Kusakabe T, Xia Q. Identification of a new Sprouty protein responsible for the inhibition of the Bombyx mori nucleopolyhedrovirus reproduction. PLoS One 2014; 9:e99200. [PMID: 24915434 PMCID: PMC4051654 DOI: 10.1371/journal.pone.0099200] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2014] [Accepted: 05/12/2014] [Indexed: 11/18/2022] Open
Abstract
The rat sarcoma-extracellular signal regulated kinase mitogen-activated protein kinases pathway, one of the most ancient signaling pathways, is crucial for the defense against Bombyx mori nucleopolyhedrovirus (BmNPV) infection. Sprouty (Spry) proteins can inhibit the activity of this pathway by receptor tyrosine kinases. We cloned and identified a new B. mori gene with a Spry domain similar to the Spry proteins of other organisms, such as fruitfly, mouse, human, chicken, Xenopus and zebrafish, and named it BmSpry. The gene expression analysis showed that BmSpry was transcribed in all of the examined tissues and in all developmental stages from embryo to adult. BmSpry also induced expression of BmNPV in the cells. Our results indicated: (1) the knock-down of BmSpry led to increased BmNPV replication and silkworm larvae mortality; (2) over-expression of BmSpry led to reduced BmNPV replication; and (3) BmSpry regulated the activation of ERK and inhibited BmNPV replication. These results showed that BmSpry plays a crucial role in the antiviral defense of the silkworm both in vitro and in vivo.
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Affiliation(s)
- Shengkai Jin
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Tingcai Cheng
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Liang Jiang
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Ping Lin
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Qiong Yang
- Sericulture and Farm Product Processing Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Yang Xiao
- Sericulture and Farm Product Processing Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Takahiro Kusakabe
- Laboratory of Silkworm Science, Kyushu University Graduate School of Bioresource and Bioenvironmental Sciences, Fukuoka, Japan
| | - Qingyou Xia
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
- * E-mail:
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17
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Ma L, Ma Q, Li X, Cheng L, Li K, Li S. Transcriptomic analysis of differentially expressed genes in the Ras1(CA)-overexpressed and wildtype posterior silk glands. BMC Genomics 2014; 15:182. [PMID: 24606580 PMCID: PMC4029079 DOI: 10.1186/1471-2164-15-182] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Accepted: 02/27/2014] [Indexed: 11/24/2022] Open
Abstract
Background Using the piggyBac-mediated GAL4/UAS transgenic system established in the silkworm, Bombyx mori, we have previously reported that overexpression of the Ras1CA oncogene specifically in the posterior silk gland (PSG) improved cell growth, fibroin synthesis, and thus silk yield. However, the detailed molecular mechanism remains to be fully elucidated. To achieve this goal, Illumina sequencing was used in the present study to compare the transcriptomes of the Ras1CA-overexpressed and wildtype PSGs. Results The transcriptomic sequencing results in 56 million reads following filtering steps. Most of the reads (~70%) are successfully mapped to the Bombyx genome. The mapped reads are situated within at least 9,133 predicted genes, covering 62.46% genes of the Bombyx genome. GO annotation shows that 2512 of the 2,636 differentially expressed genes (DEGs) are mostly distributed in metabolic process, cell and cell part, and binding, and KEGG annotation shows that 1,941 DEGs are mapped into 277 pathways. Importantly, Ras1CA overexpression in the PSG upregulated many DEGs distributed in “pathways in cancer”, “insulin signaling pathway”, and “MAPK signaling pathway” as well as “purine metabolism” and “pyrimidine metabolism”. Transcriptional regulation of these DEGs was verified by quantitative real-time PCR. Moreover, injection of small-molecule chemical inhibitors of the Ras1 downstream effectors into the Ras1CA-overexpressed silkworms revealed that both Raf-MAPK and PI3K-TORC1 pathways are required for the Ras1-induced DEG expression. Conclusion The transcriptomic analysis illustrates that, apart from phosphorylational regulation, Ras1 activates its downstream Raf-MAPK and PI3K-TORC1 pathways at the transcriptional level. Meanwhile, Ras1 increases DNA content and induces endoreplication, at least in part, by upregulating genes in “nucleotide metabolism” and “cell cycle”. This study provides further insights into the molecular mechanism of how Ras1CA overexpression in the PSG improves silk yield. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-182) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | - Leilei Cheng
- Key Laboratory of 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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Xia Q, Li S, Feng Q. Advances in silkworm studies accelerated by the genome sequencing of Bombyx mori. ANNUAL REVIEW OF ENTOMOLOGY 2013; 59:513-536. [PMID: 24160415 DOI: 10.1146/annurev-ento-011613-161940] [Citation(s) in RCA: 193] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Significant progress has been achieved in silkworm (Bombyx mori) research since the last review on this insect was published in this journal in 2005. In this article, we review the new and exciting progress and discoveries that have been made in B. mori during the past 10 years, which include the construction of a fine genome sequence and a genetic variation map, the evolution of genomes, the advent of functional genomics, the genetic basis of silk production, metamorphic development, immune response, and the advances in genetic manipulation. These advances, which were accelerated by the genome sequencing project, have promoted B. mori as a model organism not only for lepidopterans but also for general biology.
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Affiliation(s)
- Qingyou Xia
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400715, China;
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