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Mori BA, Coutu C, Erlandson MA, Hegedus DD. Exploring the contribution of the salivary gland and midgut to digestion in the swede midge (Contarinia nasturtii) through a genomics-guided approach. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2024; 116:e22135. [PMID: 39038196 DOI: 10.1002/arch.22135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Revised: 06/28/2024] [Accepted: 07/05/2024] [Indexed: 07/24/2024]
Abstract
The larvae of Contarinia nasturtii (Kieffer) (Diptera: Cecidomyiidae), the swede midge, targets the meristem of brassica crops where they induce the formation of galls and disrupt seed and vegetable production. Previously, we examined the salivary gland transcriptome of newly-hatched first instar larvae as they penetrated the host and initiated gall formation. Here we examine the salivary gland and midgut transcriptome of third instar larvae and provide evidence for cooperative nutrient acquisition beginning with secretion of enzymes and feeding facilitators followed by gastrointestinal digestion. Sucrose, presumably obtained from the phloem, appeared to be a major nutrient source as several α-glucosidases (sucrases, maltases) and β-fructofuranosidases (invertases) were identified. Genes encoding β-fructofuranosidases/invertases were among the most highly expressed in both tissues and represented two distinct gene families that may have originated via horizontal gene transfer from bacteria. The importance of the phloem as a nutrient source is underscored by the expression of genes encoding regucalcin and ARMET (arginine-rich mutated in early stages of tumor) which interfere with calcium signalling and prevent sieve tube occlusion. Lipids, proteins, and starch appear to serve as a secondary nutrient sources. Genes encoding enzymes involved in the detoxification of glucosinolates (myrosinases, arylsulfatases, and glutathione-S-transferases) were expressed indicative of Brassicaceae host specialization. The midgut expressed simple peritrophins and mucins typical of those found in Type II peritrophic matrices, the first such description for a gall midge.
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Affiliation(s)
- Boyd A Mori
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
| | - Cathy Coutu
- Agriculture and Agri-Food Canada, Saskatoon Research and Development Centre, Saskatoon, Saskatchewan, Canada
| | - Martin A Erlandson
- Agriculture and Agri-Food Canada, Saskatoon Research and Development Centre, Saskatoon, Saskatchewan, Canada
| | - Dwayne D Hegedus
- Agriculture and Agri-Food Canada, Saskatoon Research and Development Centre, Saskatoon, Saskatchewan, Canada
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Liang Y, Xu W, Zhou Y, Gao Y, Tian H, Wu X, Xu Y, Wang H. Midgut membrane protein BmSUH facilitates Bombyx mori nucleopolyhedrovirus oral infection. PLoS Pathog 2022; 18:e1010938. [PMID: 36383572 PMCID: PMC9668127 DOI: 10.1371/journal.ppat.1010938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 10/19/2022] [Indexed: 11/17/2022] Open
Abstract
Baculoviruses are virulent pathogens that infect a wide range of insects. They initiate infections via specific interactions between the structural proteins on the envelopes of occlusion-derived virions (ODVs) and the midgut cell surface receptors in hosts. However, host factors that are hijacked by baculoviruses for efficient infection remain largely unknown. In this study, we identified a membrane-associated protein sucrose hydrolase (BmSUH) as an ODV binding factor during Bombyx mori nucleopolyhedrovirus (BmNPV) primary infection. BmSUH was specifically expressed in the midgut microvilli where the ODV-midgut fusion happened. Knockout of BmSUH by CRISPR/Cas9 resulted in a significantly higher survival rate after BmNPV orally infection. Liquid chromatography-tandem mass spectrometry analysis and co-immunoprecipitation analysis demonstrated that PIF protein complex required for ODV binding could interact with BmSUH. Furthermore, fluorescence dequenching assay showed that the amount of ODV binding and fusion to the midgut decreased in BmSUH mutants compared to wild-type silkworm, suggesting the role of BmSUH as an ODV binding factor that mediates the ODV entry process. Based on a multilevel survey, the data showed that BmSUH acted as a host factor that facilitates BmNPV oral infection. More generally, this study indicated that disrupting essential protein-protein interactions required for baculovirus efficient entry may be broadly applicable to against viral infection. Baculoviridae is a large family of pathogens that infect insects and frequently cause fatal diseases. Bombyx mori nucleopolyhedrovirus (BmNPV) is a major threat to the sericulture industry. Although we have learned a lot about baculoviruses over the past several decades, the detailed interaction patterns between host proteins and viral proteins that lead to infection remain underexplored. Here, we determined that BmSUH, a midgut microvilli protein, was required for the efficient oral infection of BmNPV. Our research suggests that BmSUH mediates the entry of occlusion-derived virions into the midgut epithelia by interacting with per os infectivity factors. According to the findings, inhibition of viral binding to host cells is an attractive strategy to prevent infection. This study provides an approach for preventing BmNPV infection through developing genetic resistance to viruses by using CRISPR/Cas9 system to abolish the host factors that are essential for viral entry.
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Affiliation(s)
- Yanting Liang
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Weifan Xu
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Yanyan Zhou
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Yun Gao
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Huan Tian
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Xiaofeng Wu
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Yusong Xu
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Huabing Wang
- College of Animal Sciences, Zhejiang University, Hangzhou, China
- * E-mail:
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Dai X, Kiuchi T, Zhou Y, Jia S, Xu Y, Katsuma S, Shimada T, Wang H. Horizontal Gene Transfer and Gene Duplication of β-Fructofuranosidase Confer Lepidopteran Insects Metabolic Benefits. Mol Biol Evol 2021; 38:2897-2914. [PMID: 33739418 PMCID: PMC8233494 DOI: 10.1093/molbev/msab080] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Horizontal gene transfer (HGT) is a potentially critical source of material for ecological adaptation and the evolution of novel genetic traits. However, reports on posttransfer duplication in organism genomes are lacking, and the evolutionary advantages conferred on the recipient are generally poorly understood. Sucrase plays an important role in insect physiological growth and development. Here, we performed a comprehensive analysis of the evolution of insect β-fructofuranosidase transferred from bacteria via HGT. We found that posttransfer duplications of β-fructofuranosidase were widespread in Lepidoptera and sporadic occurrences of β-fructofuranosidase were found in Coleoptera and Hymenoptera. β-fructofuranosidase genes often undergo modifications, such as gene duplication, differential gene loss, and changes in mutation rates. Lepidopteran β-fructofuranosidase gene (SUC) clusters showed marked divergence in gene expression patterns and enzymatic properties in Bombyx mori (moth) and Papilio xuthus (butterfly). We generated SUC1 mutations in B. mori using CRISPR/Cas9 to thoroughly examine the physiological function of SUC. BmSUC1 mutant larvae were viable but displayed delayed growth and reduced sucrase activities that included susceptibility to the sugar mimic alkaloid found in high concentrations in mulberry. BmSUC1 served as a critical sucrase and supported metabolic homeostasis in the larval midgut and silk gland, suggesting that gene transfer of β-fructofuranosidase enhanced the digestive and metabolic adaptation of lepidopteran insects. These findings highlight not only the universal function of β-fructofuranosidase with a link to the maintenance of carbohydrate metabolism but also an underexplored function in the silk gland. This study expands our knowledge of posttransfer duplication and subsequent functional diversification in the adaptive evolution and lineage-specific adaptation of organisms.
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Affiliation(s)
- Xiangping Dai
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Takashi Kiuchi
- Laboratory of Insect Genetics and Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Yanyan Zhou
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Shunze Jia
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Yusong Xu
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Susumu Katsuma
- Laboratory of Insect Genetics and Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Toru Shimada
- Laboratory of Insect Genetics and Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan.,Department of Life Science, Faculty of Science, Gakushuin University, Tokyo, Japan
| | - Huabing Wang
- College of Animal Sciences, Zhejiang University, Hangzhou, China
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Miyazaki T, Oba N, Park EY. Structural insight into the substrate specificity of Bombyx mori β-fructofuranosidase belonging to the glycoside hydrolase family 32. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2020; 127:103494. [PMID: 33132139 DOI: 10.1016/j.ibmb.2020.103494] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 10/20/2020] [Accepted: 10/20/2020] [Indexed: 06/11/2023]
Abstract
Sucrose-hydrolyzing enzymes are largely divided into β-fructofuranosidase and sucrose α-glucosidase. The domestic silkworm Bombyx mori possesses both enzymes, BmSUC1 and BmSUH, belonging to the glycoside hydrolase family 32 (GH32) and GH13, respectively. BmSUC1 was presumed to be acquired by horizontal gene transfer from bacteria based on phylogenetic analysis and related to tolerance to sugar-mimic alkaloids contained in mulberry latex. Here we investigated the substrate specificity of recombinant BmSUC1 that can hydrolyze not only sucrose but also fructooligosaccharides and fructans, and revealed that the enzyme was competitively inhibited by 1,4-dideoxy-1,4-imino-D-arabinitol, one of the alkaloids. Moreover, the crystal structures of BmSUC1 in apo form and complex with sucrose were determined, and the active site pocket was shallow and suitable for shorter substrates but was related to more relaxed substrate specificity than the strict sucrose α-glucosidase BmSUH. Considering together with the distribution of BmSUC1-orthologous genes in many lepidopterans, our results suggest that BmSUC1 contributes to the digestion of fructooligosaccharides and fructans derived from feed plants.
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Affiliation(s)
- Takatsugu Miyazaki
- Green Chemistry Research Division, Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan; Department of Applied Life Sciences, Faculty of Agriculture, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan.
| | - Nozomi Oba
- Department of Applied Life Sciences, Faculty of Agriculture, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan
| | - Enoch Y Park
- Green Chemistry Research Division, Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan; Department of Applied Life Sciences, Faculty of Agriculture, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan
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5
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Structure-function analysis of silkworm sucrose hydrolase uncovers the mechanism of substrate specificity in GH13 subfamily 17 exo-α-glucosidases. J Biol Chem 2020; 295:8784-8797. [PMID: 32381508 PMCID: PMC7324511 DOI: 10.1074/jbc.ra120.013595] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 05/05/2020] [Indexed: 01/07/2023] Open
Abstract
The domestic silkworm Bombyx mori expresses two sucrose-hydrolyzing enzymes, BmSUH and BmSUC1, belonging to glycoside hydrolase family 13 subfamily 17 (GH13_17) and GH32, respectively. BmSUH has little activity on maltooligosaccharides, whereas other insect GH13_17 α-glucosidases are active on sucrose and maltooligosaccharides. Little is currently known about the structural mechanisms and substrate specificity of GH13_17 enzymes. In this study, we examined the crystal structures of BmSUH without ligands; in complexes with substrates, products, and inhibitors; and complexed with its covalent intermediate at 1.60-1.85 Å resolutions. These structures revealed that the conformations of amino acid residues around subsite -1 are notably different at each step of the hydrolytic reaction. Such changes have not been previously reported among GH13 enzymes, including exo- and endo-acting hydrolases, such as α-glucosidases and α-amylases. Amino acid residues at subsite +1 are not conserved in BmSUH and other GH13_17 α-glucosidases, but subsite -1 residues are absolutely conserved. Substitutions in three subsite +1 residues, Gln191, Tyr251, and Glu440, decreased sucrose hydrolysis and increased maltase activity of BmSUH, indicating that these residues are key for determining its substrate specificity. These results provide detailed insights into structure-function relationships in GH13 enzymes and into the molecular evolution of insect GH13_17 α-glucosidases.
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6
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Dai X, Li R, Li X, Liang Y, Gao Y, Xu Y, Shi L, Zhou Y, Wang H. Gene duplication and subsequent functional diversification of sucrose hydrolase in Papilio xuthus. INSECT MOLECULAR BIOLOGY 2019; 28:862-872. [PMID: 31155808 DOI: 10.1111/imb.12603] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 04/12/2019] [Accepted: 05/23/2019] [Indexed: 06/09/2023]
Abstract
Sucrose is the main product of photosynthesis in plants, providing a rich carbon and energy source for the physiological growth and development of insects. In a previous study, we identified a novel sucrose hydrolase (SUH) in the larval midgut of moths. Intriguingly, there are two copies of Suh, namely Suh1 and Suh2, in several species of butterflies. However, the biochemical characteristics of SUHs in butterflies remain unclear. In this study, we found that this duplication and subsequent diversification produced two Suh genes in Papilio xuthus. These two PxSuh genes were significantly divergent in terms of their expression pattern and enzyme properties. PxSuh messenger RNA expression was highest during the larval stage, reduced in the prepupal and pupal stages and, for PxSuh1, slightly increased again in the adult. The observed levels of PxSuh2 were overall below those of PxSuh1 amongst the development stages examined. Compared with PxSUH2, which has maintained the original gene function of maltose hydrolysis, PxSUH1 exhibits substrate specificity for sucrose with an optimum enzyme activity occurring at an alkaline pH. The data show that PxSuh1 is evolutionarily adapted for effective functioning in an alkaline digestive system. Furthermore, we find that functional diversification of Suh facilitates P. xuthus to digestive carbohydrate of host plants. Thus, our findings offer new insights into the ecological and evolutionary adaptation of digestive enzymes in butterflies.
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Affiliation(s)
- X Dai
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - R Li
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - X Li
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Y Liang
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Y Gao
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Y Xu
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - L Shi
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Y Zhou
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - H Wang
- College of Animal Sciences, Zhejiang University, Hangzhou, China
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7
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Zhou Y, Li X, Katsuma S, Xu Y, Shi L, Shimada T, Wang H. Duplication and diversification of trehalase confers evolutionary advantages on lepidopteran insects. Mol Ecol 2019; 28:5282-5298. [PMID: 31674075 DOI: 10.1111/mec.15291] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 10/23/2019] [Indexed: 01/06/2023]
Abstract
Gene duplication provides a major source of new genes for evolutionary novelty and ecological adaptation. However, the maintenance of duplicated genes and their relevance to adaptive evolution has long been debated. Insect trehalase (Treh) plays key roles in energy metabolism, growth, and stress recovery. Here, we show that the duplication of Treh in Lepidoptera (butterflies and moths) is linked with their adaptation to various environmental stresses. Generally, two Treh genes are present in insects: Treh1 and Treh2. We report three distinct forms of Treh in lepidopteran insects, where Treh1 was duplicated into two gene clusters (Treh1a and Treh1b). These gene clusters differ in gene expression patterns, enzymatic properties, and subcellular localizations, suggesting that the enzymes probably underwent sub- and/or neofunctionalization in the lepidopteran insects. Interestingly, selective pressure analysis provided significant evidence of positive selection on duplicate Treh1b gene in lepidopteran insect lineages. Most positively selected sites were located in the alpha-helical region, and several sites were close to the trehalose binding and catalytic sites. Subcellular adaptation of duplicate Treh1b driven by positive selection appears to have occurred as a result of selected changes in specific sequences, allowing for rapid reprogramming of duplicated Treh during evolution. Our results suggest that gene duplication of Treh and subsequent functional diversification could increase the survival rate of lepidopteran insects through various regulations of intracellular trehalose levels, facilitating their adaptation to diverse habitats. This study provides evidence regarding the mechanism by which gene family expansion can contribute to species adaptation through gene duplication and subsequent functional diversification.
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Affiliation(s)
- Yanyan Zhou
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Xiaotong Li
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Susumu Katsuma
- Laboratory of Insect Genetics and Bioscience, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo, Japan
| | - Yusong Xu
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Liangen Shi
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Toru Shimada
- Laboratory of Insect Genetics and Bioscience, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo, Japan
| | - Huabing Wang
- College of Animal Sciences, Zhejiang University, Hangzhou, China
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Li X, Shi L, Dai X, Chen Y, Xie H, Feng M, Chen Y, Wang H. Expression plasticity and evolutionary changes extensively shape the sugar-mimic alkaloid adaptation of nondigestive glucosidase in lepidopteran mulberry-specialist insects. Mol Ecol 2018; 27:2858-2870. [PMID: 29752760 DOI: 10.1111/mec.14720] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 04/10/2018] [Accepted: 04/17/2018] [Indexed: 01/28/2023]
Abstract
During the co-evolutionary arms race between plants and herbivores, insects evolved systematic adaptive plasticity to minimize the chemical defence effects of their host plants. Previous studies mainly focused on the expressional plasticity of enzymes in detoxification and digestion. However, the expressional response and adaptive evolution of other fundamental regulators against host phytochemicals are largely unknown. Glucosidase II (GII), which is composed of a catalytic GIIα subunit and a regulatory GIIβ subunit, is an evolutionarily conserved enzyme that regulates glycoprotein folding. In this study, we found that GIIα expression of the mulberry-specialist insect was significantly induced by mulberry leaf extract, 1-deoxynojirimycin (1-DNJ), whereas GIIβ transcripts were not significantly changed. Moreover, positive selection was detected in GIIα when the mulberry-specialist insects diverged from the lepidopteran order, whereas GIIβ was mainly subjected to purifying selection, thus indicating an asymmetrically selective pressure of GII subunits. In addition, positively selected sites were enriched in the GIIα of mulberry-specialist insects and located around the 1-DNJ-binding sites and in the C-terminal region, which could result in conformational changes that affect catalytic activity and substrate-binding efficiency. These results show that expression plasticity and evolutionary changes extensively shape sugar-mimic alkaloids adaptation of nondigestive glucosidase in lepidopteran mulberry-specialist insects. Our study provides novel insights into a deep understanding of the sequestration and adaptation of phytophagous specialists to host defensive compounds.
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Affiliation(s)
- Xiaotong Li
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Liangen Shi
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Xiangping Dai
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Yajie Chen
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Hongqing Xie
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Min Feng
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Yuyin Chen
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Huabing Wang
- College of Animal Sciences, Zhejiang University, Hangzhou, China
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Gan Q, Zhang X, Zhang D, Shi L, Zhou Y, Sun T, Jiang S, Gao J, Meng Y. BmSUC1 is essential for glycometabolism modulation in the silkworm, Bombyx mori. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2018; 1861:543-553. [PMID: 29660529 DOI: 10.1016/j.bbagrm.2018.04.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 04/10/2018] [Accepted: 04/10/2018] [Indexed: 01/07/2023]
Abstract
Sucrose is the most commonly transported sugar in plants and is easily assimilated by insects to fulfill the requirement of physiological metabolism. BmSuc1 is a novel animal β-fructofuranosidase (β-FFase, EC 3.2.1.26)-encoding gene that was firstly cloned and identified in silkworm, Bombyx mori. BmSUC1 was presumed to play an important role in the silkworm-mulberry enzymatic adaptation system by effectively hydrolyzing sucrose absorbed from mulberry leaves. However, this has not been proved with direct evidence thus far. In this study, we investigated sucrose hydrolysis activity in the larval midgut of B. mori by inhibition tests and found that sucrase activity mainly stemmed from β-FFase, not α-glucosidase. Next, we performed shRNA-mediated transgenic RNAi to analyze the growth characteristics of silkworm larvae and variations in glycometabolism in vivo in transgenic silkworms. The results showed that in the RNAi-BmSuc1 transgenic line, larval development was delayed, and their body size was markedly reduced. Finally, the activity of several disaccharidases alone in the midgut and the sugar distribution, total sugar and glycogen in the midgut, hemolymph and fat body were then determined and compared. Our results demonstrated that silencing BmSuc1 significantly reduced glucose and apparently activated maltase and trehalase in the midgut. Together with a clear decrease in both glycogen and trehalose in the fat body, we conclude that BmSUC1 acts as an essential sucrase by directly modulating the degree of sucrose hydrolysis in the silkworm larval midgut, and insufficient sugar storage in the fat body may be responsible for larval malnutrition and abnormal petite phenotypes.
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Affiliation(s)
- Quan Gan
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, Anhui, China; Anhui International Joint Research and Development Center of Sericulture Resources Utilization, Hefei 230036, Anhui, China
| | - Xinwei Zhang
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, Anhui, China; Anhui International Joint Research and Development Center of Sericulture Resources Utilization, Hefei 230036, Anhui, China
| | - Daobo Zhang
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, Anhui, China
| | - Liang Shi
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, Anhui, China
| | - Yue Zhou
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, Anhui, China
| | - Tongtong Sun
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, Anhui, China
| | - Song Jiang
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, Anhui, China
| | - Junshan Gao
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, Anhui, China; Anhui International Joint Research and Development Center of Sericulture Resources Utilization, Hefei 230036, Anhui, China.
| | - Yan Meng
- School of Life Sciences, Anhui Agricultural University, Hefei 230036, Anhui, China; Anhui International Joint Research and Development Center of Sericulture Resources Utilization, Hefei 230036, Anhui, China.
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Liu Y, Su H, Li R, Li X, Xu Y, Dai X, Zhou Y, Wang H. Comparative transcriptome analysis of Glyphodes pyloalis Walker (Lepidoptera: Pyralidae) reveals novel insights into heat stress tolerance in insects. BMC Genomics 2017; 18:974. [PMID: 29258441 PMCID: PMC5735938 DOI: 10.1186/s12864-017-4355-5] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 11/28/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Heat tolerance is a key parameter that affects insect distribution and abundance. Glyphodes pyloalis Walker (Lepidoptera: Pyralidae) is a devastating pest of mulberry in the main mulberry-growing regions and can cause tremendous losses to sericulture by directly feeding on mulberry leaves and transmitting viruses to Bombyx mori. Moreover, G. pyloalis shows a prominent capacity for adaptation to daily and seasonal temperature fluctuations and can survive several hours under high temperature. To date, the molecular mechanism underlying the outstanding adaptability of this pest to high temperature remains unclear. RESULTS In this study, we performed comparative transcriptome analyses on G. pyloalis exposed to 25 and 40 °C for 4 h. We obtained 34,034 unigenes and identified 1275 and 1222 genes significantly upregulated or downregulated, respectively, by heat stress. Data from the transcriptome analyses indicated that some processes involved in heat tolerance are conserved, such as high expression of heat shock protein (HSP) genes and partial repression of metabolism progress. In addition, vitamin digestion and absorption pathways and detoxification pathways identified here provided new insights for the investigation of the molecular mechanisms of heat stress tolerance. Furthermore, transcriptome analysis indicated that immune and phosphatidylinositol signaling system have a close relationship with heat tolerance. In addition, the expression patterns of ten randomly selected genes, such as HSP and cytochrome P450, were consistent with the transcriptome results obtained through quantitative real-time PCR. CONCLUSIONS Comparisons among transcriptome results revealed the upregulation of HSPs and genes involved in redox homeostasis, detoxication, and immune progress. However, many metabolism progresses, such as glycolysis/gluconeogenesis and fatty acid biosynthesis, were partially repressed. The results reflected that the heat tolerance of G. pyloalis is a fairly complicated process and related to a broad range of physiological regulations. Our study can improve understanding on the mechanisms of insect thermal tolerance.
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Affiliation(s)
- Yuncai Liu
- College of Animal Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Hang Su
- College of Animal Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Rongqiao Li
- College of Animal Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Xiaotong Li
- College of Animal Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Yusong Xu
- College of Animal Sciences, Zhejiang University, Hangzhou, 310058, China.
| | - Xiangping Dai
- College of Animal Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Yanyan Zhou
- College of Animal Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Huabing Wang
- College of Animal Sciences, Zhejiang University, Hangzhou, 310058, China.
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Whon TW, Shin NR, Jung MJ, Hyun DW, Kim HS, Kim PS, Bae JW. Conditionally Pathogenic Gut Microbes Promote Larval Growth by Increasing Redox-Dependent Fat Storage in High-Sugar Diet-Fed Drosophila. Antioxid Redox Signal 2017; 27:1361-1380. [PMID: 28462587 DOI: 10.1089/ars.2016.6790] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
AIMS Changes in the composition of the gut microbiota contribute to the development of obesity and subsequent complications that are associated with metabolic syndrome. However, the role of increased numbers of certain bacterial species during the progress of obesity and factor(s) controlling the community structure of gut microbiota remain unclear. Here, we demonstrate the inter-relationship between Drosophila melanogaster and their resident gut microbiota under chronic high-sugar diet (HSD) conditions. RESULTS Chronic feeding of an HSD to Drosophila resulted in a predominance of resident uracil-secreting bacteria in the gut. Axenic insects mono-associated with uracil-secreting bacteria or supplemented with uracil under HSD conditions promoted larval development. Redox signaling induced by bacterial uracil promoted larval growth by regulating sugar and lipid metabolism via activation of p38a mitogen-activated protein kinase. INNOVATION The present study identified a new redox-dependent mechanism by which uracil-secreting bacteria (previously regarded as opportunistic pathobionts) protect the host from metabolic perturbation under chronic HSD conditions. CONCLUSION These results illustrate how Drosophila and gut microbes form a symbiotic relationship under stress conditions, and changes in the gut microbiota play an important role in alleviating deleterious diet-derived effects such as hyperglycemia. Antioxid. Redox Signal. 27, 1361-1380.
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Affiliation(s)
- Tae Woong Whon
- Department of Life and Nanopharmaceutical Sciences and Department of Biology, Kyung Hee University , Seoul, Republic of Korea
| | - Na-Ri Shin
- Department of Life and Nanopharmaceutical Sciences and Department of Biology, Kyung Hee University , Seoul, Republic of Korea
| | - Mi-Ja Jung
- Department of Life and Nanopharmaceutical Sciences and Department of Biology, Kyung Hee University , Seoul, Republic of Korea
| | - Dong-Wook Hyun
- Department of Life and Nanopharmaceutical Sciences and Department of Biology, Kyung Hee University , Seoul, Republic of Korea
| | - Hyun Sik Kim
- Department of Life and Nanopharmaceutical Sciences and Department of Biology, Kyung Hee University , Seoul, Republic of Korea
| | - Pil Soo Kim
- Department of Life and Nanopharmaceutical Sciences and Department of Biology, Kyung Hee University , Seoul, Republic of Korea
| | - Jin-Woo Bae
- Department of Life and Nanopharmaceutical Sciences and Department of Biology, Kyung Hee University , Seoul, Republic of Korea
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12
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Zhou Y, Wang L, Li R, Liu M, Li X, Su H, Xu Y, Wang H. Secreted glycoprotein BmApoD1 plays a critical role in anti-oxidation and anti-apoptosis in Bombyx mori. Biochem Biophys Res Commun 2017; 495:839-845. [PMID: 29128356 DOI: 10.1016/j.bbrc.2017.11.044] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 11/07/2017] [Indexed: 12/29/2022]
Abstract
Recent studies highlighted that apolipoprotein D (ApoD) and its homologs exert neuroprotective and antioxidant functions in mammals and Drosophila. Unlike mammals and Drosophila, lepidopteran insects possess three distinct ApoD homologs. However, few information on their functions in lepidopteran insects are available. In this study, we investigated the protective potential of a novel ApoD homolog, BmApoD1, in Bombyx mori. Quantitative PCR analyses demonstrated that BmApoD1 is extensively expressed at low levels during the larval stage but abundantly expressed in the testis during the pupal and adult stages. Tryptophan fluorescence titration demonstrated that recombinant BmApoD1 protein can bind retinoic acid and ergosterol. In addition, we provided evidence that N-linked glycans of BmApoD1 are essential to BmApoD1 secretion, and three residues, namely, Asp69, Asp104, and Asp196, are the glycosylation sites of BmApoD1. Furthermore, we showed that BmApoD1 is significantly up-regulated in the larvae after oxidant or starvation treatment. The recombinant BmApoD1 protein can protect cells from oxidative stress induced by H2O2 and reduce actinomycin D-induced cell apoptosis. These observations, together with the transcriptional up-regulation of BmApoD1 in several tissues upon oxidative insult, identify BmApoD1 as a potent antioxidant. Our results demonstrate that BmApoD1 is critical for metabolic adaptation of B. mori to environmental challenges.
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Affiliation(s)
- Yanyan Zhou
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Li Wang
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Rongqiao Li
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Minmin Liu
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Xiaotong Li
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Hang Su
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yusong Xu
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Huabing Wang
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China.
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13
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Li X, Shi L, Zhou Y, Xie H, Dai X, Li R, Chen Y, Wang H. Molecular evolutionary mechanisms driving functional diversification of α-glucosidase in Lepidoptera. Sci Rep 2017; 7:45787. [PMID: 28401928 PMCID: PMC5388851 DOI: 10.1038/srep45787] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 03/01/2017] [Indexed: 01/28/2023] Open
Abstract
The digestive tract of lepidopteran insects is unique given its highly alkaline pH. The adaptive plasticity of digestive enzymes in this environment is crucial to the highly-efficient nutritional absorption in Lepidoptera. However, little is known about the molecular adaptation of digestive enzymes to this environment. Here, we show that lepidopteran α-glucosidase, a pivotal digestive enzyme, diverged into sucrose hydrolase (SUH) and other maltase subfamilies. SUH, which is specific for sucrose, was only detected in Lepidoptera. It suggests that lepidopteran insects have evolved an enhanced ability to hydrolyse sucrose, their major energy source. Gene duplications and exon-shuffling produced multiple copies of α-glucosidase in different microsyntenic regions. Furthermore, SUH showed significant functional divergence (FD) compared with maltase, which was affected by positive selection at specific lineages and codons. Nine sites, which were involved in both FD and positive selection, were located around the ligand-binding groove of SUH. These sites could be responsible for the ligand-binding preference and hydrolytic specificity of SUH for sucrose, and contribute to its conformational stability. Overall, our study demonstrated that positive selection is an important evolutionary force for the adaptive diversification of α-glucosidase, and for the exclusive presence of membrane-associated SUHs in the unique lepidopteran digestive tract.
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Affiliation(s)
- Xiaotong Li
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Liangen Shi
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yanyan Zhou
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Hongqing Xie
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Xiangping Dai
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Rongqiao Li
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yuyin Chen
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Huabing Wang
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
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