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Perera OP, Shelby KS, Popham HJR, Gould F, Adang MJ, Jurat-Fuentes JL. Generation of a Transcriptome in a Model Lepidopteran Pest, Heliothis virescens, Using Multiple Sequencing Strategies for Profiling Midgut Gene Expression. PLoS One 2015; 10:e0128563. [PMID: 26047101 PMCID: PMC4457788 DOI: 10.1371/journal.pone.0128563] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 04/29/2015] [Indexed: 02/04/2023] Open
Abstract
Heliothine pests such as the tobacco budworm, Heliothis virescens (F.), pose a significant threat to production of a variety of crops and ornamental plants and are models for developmental and physiological studies. The efforts to develop new control measures for H. virescens, as well as its use as a relevant biological model, are hampered by a lack of molecular resources. The present work demonstrates the utility of next-generation sequencing technologies for rapid molecular resource generation from this species for which lacks a sequenced genome. In order to amass a de novo transcriptome for this moth, transcript sequences generated from Illumina, Roche 454, and Sanger sequencing platforms were merged into a single de novo transcriptome assembly. This pooling strategy allowed a thorough sampling of transcripts produced under diverse environmental conditions, developmental stages, tissues, and infections with entomopathogens used for biological control, to provide the most complete transcriptome to date for this species. Over 138 million reads from the three platforms were assembled into the final set of 63,648 contigs. Of these, 29,978 had significant BLAST scores indicating orthologous relationships to transcripts of other insect species, with the top-hit species being the monarch butterfly (Danaus plexippus) and silkworm (Bombyx mori). Among identified H. virescens orthologs were immune effectors, signal transduction pathways, olfactory receptors, hormone biosynthetic pathways, peptide hormones and their receptors, digestive enzymes, and insecticide resistance enzymes. As an example, we demonstrate the utility of this transcriptomic resource to study gene expression profiling of larval midguts and detect transcripts of putative Bacillus thuringiensis (Bt) Cry toxin receptors. The substantial molecular resources described in this study will facilitate development of H. virescens as a relevant biological model for functional genomics and for new biological experimentation needed to develop efficient control efforts for this and related Noctuid pest moths.
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Affiliation(s)
- Omaththage P. Perera
- Southern Insect Management Research Unit, USDA, Agricultural Research Service, Stoneville, MS, 38776, United States of America
| | - Kent S. Shelby
- Biological Control of Insects Research Laboratory, USDA, Agricultural Research Service, Columbia, Missouri, 65203, United States of America
| | - Holly J. R. Popham
- Biological Control of Insects Research Laboratory, USDA, Agricultural Research Service, Columbia, Missouri, 65203, United States of America
| | - Fred Gould
- Dept. Entomology, North Carolina State University, Raleigh, NC, 27607, United States of America
| | - Michael J. Adang
- Dept. Entomology, University of Georgia, Athens, GA, 30602, United States of America
| | - Juan Luis Jurat-Fuentes
- Dept. Entomology and Plant Pathology, University of Tennessee, Knoxville, TN, 37996, United States of America
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152
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Chu Y, Zhou F, Liu Y, Hong F, Wang G, An C. Ostrinia furnacalis serpin-3 regulates melanization cascade by inhibiting a prophenoloxidase-activating protease. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2015; 61:53-61. [PMID: 25818483 DOI: 10.1016/j.ibmb.2015.03.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Revised: 03/01/2015] [Accepted: 03/16/2015] [Indexed: 06/04/2023]
Abstract
Serine protease cascade-mediated prophenolxidase activation is a prominent innate immune response in insect defense against the invading pathogens. Serpins regulate this reaction to avoid excessive activation. However, the function of serpins in most insect species, especially in some non-model agriculture insect pests, is largely unknown. We here cloned a full-length cDNA for a serpin, named as serpin-3, from Asian corn borer, Ostrinia furnacalis (Guenée). The open reading frame of serpin-3 encodes 462-amino acid residue protein with a 19-residue signal peptide. It contains a reactive center loop strikingly similar to the proteolytic activation site in prophenoloxidase. Sequence comparison indicates that O. furnacalis serpin-3 is an apparent ortholog of Manduca sexta serpin-3, a defined negative regulator of melanization reaction. Serpin-3 mRNA and protein levels significantly increase after a bacterial or fungal injection. Recombinant serpin-3 efficiently blocks prophenoloxidase activation in larval plasma in a concentration-dependent manner. It forms SDS-stable complexes with serine protease 13 (SP13), and prevents SP13 from cleaving prophenoloxidase. Injection of recombinant serpin-3 into larvae results in decreased fungi-induced melanin synthesis and reduced the expression of attacin, cecropin, gloverin, and peptidoglycan recognition protein-1 genes in the fat body. Altogether, serpin-3 plays important roles in the regulation of prophenoloxidase activation and antimicrobial peptide production in O. furnacalis larvae.
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Affiliation(s)
- Yuan Chu
- Department of Entomology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, 100193, China
| | - Fan Zhou
- Department of Entomology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, 100193, China
| | - Yang Liu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Fang Hong
- Department of Entomology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, 100193, China
| | - Guirong Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Chunju An
- Department of Entomology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, 100193, China.
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153
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Elmogy M, Bassal TTM, Yousef HA, Dorrah MA, Mohamed AA, Duvic B. Isolation, characterization, kinetics, and enzymatic and nonenzymatic microbicidal activities of a novel c-type lysozyme from plasma of Schistocerca gregaria (Orthoptera: Acrididae). JOURNAL OF INSECT SCIENCE (ONLINE) 2015; 15:iev038. [PMID: 25972507 PMCID: PMC4535491 DOI: 10.1093/jisesa/iev038] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Accepted: 04/15/2015] [Indexed: 05/24/2023]
Abstract
A protein, designated as Sgl, showing a muramidase lytic activity to the cell wall of the Gram-positive bacterium Micrococcus lysodeikticus was isolated for the first time from plasma of Escherichia coli-immunized fifth instar Schistocerca gregaria. The isolated Sgl was detected as a single protein band, on both native- and SDS-PAGE, has a molecular weight of ∼15.7 kDa and an isoelectric point (pI) of ca 9.3 and its antiserum has specifically recognized its isolated form. Fifty-nine percentage of Sgl lytic activity was recovered in the isolated fractions and yielded ca 126-fold increase in specific activity than that of the crude. The partial N-terminal amino acid sequence of the Sgl has 55 and 40% maximum identity with Bombyx mori and Gallus gallus c-type lysozymes, respectively. The antibacterial activity against the Gram-positive and the Gram-negative bacteria were comparatively stronger than that of the hen egg white lysozyme (HEWL). The detected Sgl poration to the inner membrane that reach a maximum ability after 3 h was suggested to operate as a nonenzymatic mechanism for Gram-negative bacterial cell lysis, as tested in a permease-deficient E. coli, ML-35 strain. Sgl showed a maximal muramidase activity at pH 6.2, 30-50°C, and 0.05 M Ca(2+) or Mg(2+); and has a Km of 0.5 μg/ml and a Vmax of 0.518 with M. lysodeikticus as a substrate. The Sgl displayed a chitinase activity against chitin with a Km of 0.93 mg/ml and a Vmax of 1.63.
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Affiliation(s)
- Mohamed Elmogy
- Department of Entomology, Faculty of Science, Cairo University, P. O. Box 12613, Giza, Egypt Department of Biology, Faculty of Applied Science, Umm AlQura University, P.O. Box 673, Makkah, KSA
| | - Taha T M Bassal
- Department of Entomology, Faculty of Science, Cairo University, P. O. Box 12613, Giza, Egypt
| | - Hesham A Yousef
- Department of Entomology, Faculty of Science, Cairo University, P. O. Box 12613, Giza, Egypt
| | - Moataza A Dorrah
- Department of Entomology, Faculty of Science, Cairo University, P. O. Box 12613, Giza, Egypt
| | - Amr A Mohamed
- Department of Entomology, Faculty of Science, Cairo University, P. O. Box 12613, Giza, Egypt
| | - Bernard Duvic
- Institut National de la Recherche Agronomique (INRA), UMR Diversité, Génomes et Interactions Microorganismes-Insectes (DGIMI), 34095 Montpellier Cedex 05, France Université Montpellier 2, UMR Diversité, Génomes et Interactions Microorganismes-Insectes (DGIMI), 34095 Montpellier Cedex 05, France
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154
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Hillyer JF. Integrated Immune and Cardiovascular Function in Pancrustacea: Lessons from the Insects. Integr Comp Biol 2015; 55:843-55. [DOI: 10.1093/icb/icv021] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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155
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Chu Y, Liu Y, Shen D, Hong F, Wang G, An C. Serine proteases SP1 and SP13 mediate the melanization response of Asian corn borer, Ostrinia furnacalis, against entomopathogenic fungus Beauveria bassiana. J Invertebr Pathol 2015; 128:64-72. [PMID: 25900291 DOI: 10.1016/j.jip.2015.02.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Revised: 02/12/2015] [Accepted: 02/26/2015] [Indexed: 01/01/2023]
Abstract
Exposure to entomopathogenic fungi is one approach for insect pest control. Little is known about the immune interactions between fungus and its insect host. Melanization is a prominent immune response in insects in defending against pathogens such as bacteria and fungi. Clip domain serine proteases in insect plasma have been implicated in the activation of prophenoloxidase, a key enzyme in the melanization. The relationship between host melanization and the infection by a fungus needs to be established. We report here that the injection of entomopathogenic fungus Beauveria bassiana induced both melanin synthesis and phenoloxidase activity in its host insect, the Asian corn borer, Ostrinia furnacalis (Guenée). qRT-PCR analysis showed several distinct patterns of expression of 13 clip-domain serine proteases in response to the challenge of fungi, with seven increased, two decreased, and four unchanged. Of special interest among these clip-domain serine protease genes are SP1 and SP13, the orthologs of Manduca sexta HP6 and PAP1 which are involved in the prophenoloxidase activation pathway. Recombinant O. furnacalis SP1 was found to activate proSP13 and induce the phenoloxidase activity in corn borer plasma. Additionally, SP13 was determined to directly cleave prophenoloxidase and therefore act as the prophenoloxidase activating protease. Our work thus reveals a biochemical mechanism in the melanization in corn borer associated with the challenge by B. bassiana injection. These insights could provide valuable information for better understanding the immune responses of Asian corn borer against B. bassiana.
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Affiliation(s)
- Yuan Chu
- Department of Entomology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, China
| | - Yang Liu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Dongxu Shen
- Department of Entomology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, China
| | - Fang Hong
- Department of Entomology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, China
| | - Guirong Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Chunju An
- Department of Entomology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, China.
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156
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Taszłow P, Wojda I. Changes in the hemolymph protein profiles in Galleria mellonella infected with Bacillus thuringiensis involve apolipophorin III. The effect of heat shock. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2015; 88:123-143. [PMID: 25308190 DOI: 10.1002/arch.21208] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
This report concerns the effect of heat shock on host-pathogen interaction in Galleria mellonella infected with Bacillus thuringiensis. We show enhanced activity against Gram-positive bacteria in the hemolymph of larvae pre-exposed to heat shock before infection with B. thuringiensis. Heat shock influenced the protein pattern in the hemolymph of infected larvae: more peptides with a molecular weight below 10 kDa were detected in comparison with nonshocked animals. Additionally, we noticed that the amount of apolipophorin III (apoLp-III) in the hemolymph decreased transiently following infection, which was considerably higher in larvae pre-exposed to heat shock. On the other hand, its expression in the fat body showed a consequent infection-induced decline, observed equally in shocked and nonshocked animals. This suggests that the amount of apoLp-III in the hemolymph of G. mellonella larvae is regulated at multiple levels. We also report that this protein is more resistant to degradation in the hemolymph of larvae pre-exposed to heat shock in comparison to nonshocked larvae. Two-dimensional analysis revealed the presence of three isoforms of apoLp-III, all susceptible to proteolytic degradation. However, one of them was the most abundant, both in the protease-treated and untreated hemolymph. Taking into consideration that, in general, apoLp-III has a stimulative effect on different immune-related hemolymph proteins and peptides, the reported findings bring us closer to understanding the effect of heat shock on the resistance of G. mellonella to infection.
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Affiliation(s)
- Paulina Taszłow
- Department of Immunobiology, Faculty of Biology and Biotechnology, Institute of Biology and Biochemistry, Maria Curie-Sklodowska University, Lublin, Poland
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157
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Booth K, Cambron L, Fisher N, Greenlee KJ. Immune Defense Varies within an Instar in the Tobacco Hornworm, Manduca sexta. Physiol Biochem Zool 2015; 88:226-36. [PMID: 25730277 DOI: 10.1086/680054] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Research on how insect immunity changes with age as insects develop within an instar, or larval developmental stage, is limited and contradictory. Insects within an instar are preparing for the next developmental stage, which may involve changes in morphology or habitat. Immunity may also vary accordingly. To determine how immunity varies in the fifth instar, we tested humoral immune responses, antimicrobial peptide activity, and phenoloxidase activity using the tobacco hornworm, Manduca sexta. We determined that while M. sexta have more robust antimicrobial peptide and phenoloxidase responses at the beginning of their fifth instar, this did not translate into better survival of bacterial infection or lower bacterial load in the hemolymph. We also determined that M. sexta injected with bacteria early in the fifth instar experience lower growth rates and longer development times than caterpillars of the same age injected with sham. This could indicate a shift in energy allocation from growth and development to metabolically costly immune responses. Because of the importance of insects as pests and pollinators, understanding how immunity varies throughout development is critical.
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Affiliation(s)
- Kimberly Booth
- Department of Biological Sciences, North Dakota State University, Fargo, North Dakota 58102; 2Department of Arts and Sciences, Aurora University, Aurora, Illinois 60506; 3Department of Veterinary and Microbiological Sciences, North Dakota State University, Fargo, North Dakota 58102
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158
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Ardisson-Araujo DMP, Rohrmann GF, Ribeiro BM, Clem RJ. Functional characterization of hesp018, a baculovirus-encoded serpin gene. J Gen Virol 2015; 96:1150-1160. [PMID: 25573886 DOI: 10.1099/vir.0.000041] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 01/05/2015] [Indexed: 12/21/2022] Open
Abstract
The serpin family of serine proteinase inhibitors plays key roles in a variety of biochemical pathways. In insects, one of the important functions carried out by serpins is regulation of the phenoloxidase (PO) cascade - a pathway that produces melanin and other compounds that are important in insect humoral immunity. Recent sequencing of the baculovirus Hemileuca sp. nucleopolyhedrovirus (HespNPV) genome revealed the presence of a gene, hesp018, with homology to insect serpins. To our knowledge, hesp018 is the first viral serpin homologue to be characterized outside of the chordopoxviruses. The Hesp018 protein was found to be a functional serpin with inhibitory activity against a subset of serine proteinases. Hesp018 also inhibited PO activation when mixed with lepidopteran haemolymph. The Hesp018 protein was secreted when expressed in lepidopteran cells and a baculovirus expressing Hesp018 exhibited accelerated production of viral progeny during in vitro infection. Expression of Hesp018 also reduced caspase activity induced by baculovirus infection, but caused increased cathepsin activity. In infected insect larvae, expression of Hesp018 resulted in faster larval melanization, consistent with increased activity of viral cathepsin. Finally, expression of Hesp018 increased the virulence of a prototype baculovirus by fourfold in orally infected neonate Trichoplusia ni larvae. Based on our observations, we hypothesize that hesp018 may have been retained in HespNPV due to its ability to inhibit the activity of select host proteinases, possibly including proteinases involved in the PO response, during infection of host insects.
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Affiliation(s)
- Daniel M P Ardisson-Araujo
- Department of Cell Biology, University of Brasilia, Brasilia, DF, Brazil.,Division of Biology, Kansas State University, Manhattan, KS, USA
| | - George F Rohrmann
- Department of Microbiology, Oregon State University, Corvallis, OR, USA
| | - Bergmann M Ribeiro
- Department of Cell Biology, University of Brasilia, Brasilia, DF, Brazil
| | - Rollie J Clem
- Division of Biology, Kansas State University, Manhattan, KS, USA
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159
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Zhang K, Tan J, Xu M, Su J, Hu R, Chen Y, Xuan F, Yang R, Cui H. A novel granulocyte-specific α integrin is essential for cellular immunity in the silkworm Bombyx mori. JOURNAL OF INSECT PHYSIOLOGY 2014; 71:61-67. [PMID: 25450560 DOI: 10.1016/j.jinsphys.2014.10.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 10/10/2014] [Accepted: 10/13/2014] [Indexed: 06/04/2023]
Abstract
Haemocytes play crucial roles in immune responses and survival in insects. Specific cell markers have proven effective in clarifying the function and haematopoiesis of haemocytes. The silkworm Bombyx mori is a good model for studying insect haemocytes; however, little is known about haemocyte-specific markers or their functions in silkworm. In this study, we identified the α subunit of integrin, BmintegrinαPS3, as being specifically and highly expressed in silkworm haemocytes. Immunofluorescence analysis validated the specificity of BmintegrinαPS3 in larval granulocytes. Further analyses indicated that haemocytes dispersed from haematopoietic organs (HPOs) into the circulating haemolymph could differentiate into granulocytes. In addition, the processes of encapsulation and phagocytosis were controlled by larval granulocytes. Our work demonstrated that BmintegrinαPS3 could be used as a specific marker for granulocytes and could be applied to future molecular cell biology studies.
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Affiliation(s)
- Kui Zhang
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716, China
| | - Juan Tan
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716, China
| | - Man Xu
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716, China
| | - Jingjing Su
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716, China
| | - Renjian Hu
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716, China
| | - Yibiao Chen
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716, China
| | - Fan Xuan
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716, China
| | - Rui Yang
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716, China
| | - Hongjuan Cui
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716, China.
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160
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Fors L, Markus R, Theopold U, Hambäck PA. Differences in cellular immune competence explain parasitoid resistance for two coleopteran species. PLoS One 2014; 9:e108795. [PMID: 25259576 PMCID: PMC4178244 DOI: 10.1371/journal.pone.0108795] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Accepted: 09/03/2014] [Indexed: 11/18/2022] Open
Abstract
The immune defence of an organism is evolving continuously, causing counteradaptations in interacting species, which in turn affect other ecological and evolutionary processes. Until recently comparative studies of species interactions and immunity, combining information from both ecological and immunological fields, have been rare. The cellular immune defense in insects, mainly mediated by circulating hemocytes, has been studied primarily in Lepidoptera and Diptera, whereas corresponding information about coleopteran species is still scarce. In the study presented here, we used two closely related chrysomelids, Galerucella pusilla and G. calmariensis (Coleoptera), both attacked by the same parasitoid, Asecodes parviclava (Hymenoptera). In order to investigate the structure of the immune system in Galerucella and to detect possible differences between the two species, we combined ecological studies with controlled parasitism experiments, followed by an investigation of the cell composition in the larval hemolymph. We found a striking difference in parasitism rate between the species, as well as in the level of successful immune response (i.e. encapsulation and melanisation of parasitoid eggs), with G. pusilla showing a much more potent immune defense than G. calmariensis. These differences were linked to differences in the larval cell composition, where hemocyte subsets in both naïve and parasitised individuals differed significantly between the species. In particular, the hemocytes shown to be active in the encapsulation process; phagocytes, lamellocytes and granulocytes, differ between the species, indicating that the cell composition reflects the ability to defend against the parasitoid.
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Affiliation(s)
- Lisa Fors
- Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm, Sweden
- * E-mail:
| | - Robert Markus
- Department of Neurosciences, Stockholm University, Stockholm, Sweden
| | - Ulrich Theopold
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Peter A. Hambäck
- Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm, Sweden
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161
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Rao XJ, Zhong X, Lin XY, Huang XH, Yu XQ. Characterization of a novel Manduca sexta beta-1, 3-glucan recognition protein (βGRP3) with multiple functions. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2014; 52:13-22. [PMID: 24952171 PMCID: PMC4143429 DOI: 10.1016/j.ibmb.2014.06.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 06/09/2014] [Accepted: 06/11/2014] [Indexed: 05/30/2023]
Abstract
Recognition of pathogens by insect pattern recognition receptors is critical to mount effective immune responses. In this study, we reported a new member (βGRP3) of the β-1, 3-glucan recognition protein (βGRP) family from the tobacco hornworm Manduca sexta. Unlike other members of the M. sexta βGRP family proteins, which contain an N-terminal small glucan binding domain and a C-terminal large glucanase-like domain, βGRP3 is 40-45 residues shorter at the N-terminus and lacks the small glucan binding domain. The glucanase-like domain of βGRP3 is most similar to that of M. sexta microbe binding protein (MBP) with 78% identity. βGRP3 transcript was mainly expressed in the fat body, and both its mRNA and protein levels were not induced by microorganisms in larvae. Recombinant βGRP3 purified from Drosophila S2 cells could bind to several Gram-negative and Gram-positive bacteria and yeast, as well as to laminarin (β-1, 3-glucan), mannan, lipopolysaccharide (LPS), lipoteichoic acid (LTA), and meso-diaminopimelic acid (DAP)-type peptidoglycan (PG), but did not bind to Lysine-type PG. Binding of βGRP3 to laminarin could be competed well by free laminarin, mannan, LPS and LTA, but almost not competed by free PGs. Recombinant βGRP3 could agglutinate Bacillus cereus and Escherichia coli in a calcium-dependent manner and showed antibacterial (bacteriostatic) activity against B. cereus, novel functions that have not been reported for the βGRP family proteins before. M. sexta βGRP3 may serve as an immune surveillance receptor with multiple functions.
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Affiliation(s)
- Xiang-Jun Rao
- School of Plant Protection, Anhui Agricultural University, Hefei, Anhui 230036, China; Division of Molecular Biology and Biochemistry, School of Biological Sciences, University of Missouri-Kansas City, 5007 Rockhill Road, Kansas City, MO 64110, USA
| | - Xue Zhong
- Division of Molecular Biology and Biochemistry, School of Biological Sciences, University of Missouri-Kansas City, 5007 Rockhill Road, Kansas City, MO 64110, USA
| | - Xin-Yu Lin
- Division of Molecular Biology and Biochemistry, School of Biological Sciences, University of Missouri-Kansas City, 5007 Rockhill Road, Kansas City, MO 64110, USA; College of Animal Sciences, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Xiao-Hong Huang
- Division of Molecular Biology and Biochemistry, School of Biological Sciences, University of Missouri-Kansas City, 5007 Rockhill Road, Kansas City, MO 64110, USA; College of Animal Sciences, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Xiao-Qiang Yu
- Division of Molecular Biology and Biochemistry, School of Biological Sciences, University of Missouri-Kansas City, 5007 Rockhill Road, Kansas City, MO 64110, USA.
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162
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Tang T, Li X, Yang X, Yu X, Wang J, Liu F, Huang D. Transcriptional response of Musca domestica larvae to bacterial infection. PLoS One 2014; 9:e104867. [PMID: 25137050 PMCID: PMC4138075 DOI: 10.1371/journal.pone.0104867] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Accepted: 07/18/2014] [Indexed: 11/18/2022] Open
Abstract
The house fly Musca domestica, a cosmopolitan dipteran insect, is a significant vector for human and animal bacterial pathogens, but little is known about its immune response to these pathogens. To address this issue, we inoculated the larvae with a mixture of Escherichia coli and Staphylococcus aureus and profiled the transcriptome 6, 24, and 48 h thereafter. Many genes known to controlling innate immunity in insects were induced following infection, including genes encoding pattern recognition proteins (PGRPs), various components of the Toll and IMD signaling pathways and of the proPO-activating and redox systems, and multiple antimicrobial peptides. Interestingly, we also uncovered a large set of novel immune response genes including two broad-spectrum antimicrobial peptides (muscin and domesticin), which might have evolved to adapt to house-fly's unique ecological environments. Finally, genes mediating oxidative phosphorylation were repressed at 48 h post-infection, suggesting disruption of energy homeostasis and mitochondrial function at the late stages of infection. Collectively, our data reveal dynamic changes in gene expression following bacterial infection in the house fly, paving the way for future in-depth analysis of M. domestica's immune system.
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Affiliation(s)
- Ting Tang
- College of Life Sciences, Hebei University, Baoding, China
| | - Xiang Li
- College of Life Sciences, Hebei University, Baoding, China
| | - Xue Yang
- College of Life Sciences, Hebei University, Baoding, China
| | - Xue Yu
- College of Life Sciences, Hebei University, Baoding, China
| | - Jianhui Wang
- Department of Pathology, Yale University, New Haven, Connecticut, United States of America
| | - Fengsong Liu
- College of Life Sciences, Hebei University, Baoding, China
- * E-mail: (FSL); (DWH)
| | - Dawei Huang
- College of Life Sciences, Hebei University, Baoding, China
- Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- * E-mail: (FSL); (DWH)
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163
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Williams M, Baxter R. The structure and function of thioester-containing proteins in arthropods. Biophys Rev 2014; 6:261-272. [PMID: 28510031 DOI: 10.1007/s12551-014-0142-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Accepted: 06/19/2014] [Indexed: 10/25/2022] Open
Abstract
Thioester-containing proteins (TEPs) form an ancient and diverse family of secreted proteins that play central roles in the innate immune response. Two families of TEPs, complement factors and α2-macroglobulins, have been known and studied in vertebrates for many years, but only in the last decade have crystal structures become available. In the same period, the presence of two additional classes of TEPs has been revealed in arthropods. In this review, we discuss the common structural features TEPs and how this knowledge can be applied to the many arthropod TEPs of unknown function. TEPs perform a wide variety of functions that are driven by different quaternary structures and protein-protein interactions between a common set of folded domains. A common theme is regulated conformational change triggered by proteolysis. Structure-function analysis of the diverse arthropod TEPs may identify not just new mechanisms in innate immunity but also interfaces between immunity, development and cell death.
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Affiliation(s)
- Marni Williams
- Department. of Chemistry, Yale University, New Haven, CT, USA
| | - Richard Baxter
- Department. of Chemistry, Yale University, New Haven, CT, USA.
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164
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Wang Y, Lu Z, Jiang H. Manduca sexta proprophenoloxidase activating proteinase-3 (PAP3) stimulates melanization by activating proPAP3, proSPHs, and proPOs. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2014; 50:82-91. [PMID: 24768974 PMCID: PMC4064829 DOI: 10.1016/j.ibmb.2014.04.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Revised: 04/09/2014] [Accepted: 04/10/2014] [Indexed: 05/22/2023]
Abstract
Melanization participates in various insect physiological processes including antimicrobial immune responses. Phenoloxidase (PO), a critical component of the enzyme system catalyzing melanin formation, is produced as an inactive precursor prophenoloxidase (proPO) and becomes active via specific proteolytic cleavage by proPO activating proteinase (PAP). In Manduca sexta, three PAPs can activate proPOs in the presence of two serine proteinase homologs (SPH1 and SPH2). While the hemolymph proteinases (HPs) that generate the active PAPs are known, it is unclear how the proSPHs (especially proSPH1) are activated. In this study, we isolated from plasma of bar-stage M. sexta larvae an Ile-Glu-Ala-Arg-p-nitroanilide hydrolyzing enzyme that cleaved the proSPHs. This proteinase, PAP3, generated active SPH1 and SPH2, which function as cofactors for PAP3 in proPO activation. Cleavage of the purified recombinant proSPHs by PAP3 yielded 38 kDa bands similar in mobility to the SPHs formed in vivo. Surprisingly, PAP3 also can activate proPAP3 to stimulate melanization in a direct positive feedback loop. The enhanced proPO activation concurred with the cleavage activation of proHP6, proHP8, proPAP1, proPAP3, proSPH1, proSPH2, proPOs, but not proHP14 or proHP21. These results indicate that PAP3, like PAP1, is a key factor of the self-reinforcing mechanism in the proPO activation system, which is linked to other immune responses in M. sexta.
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Affiliation(s)
- Yang Wang
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Zhiqiang Lu
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Haobo Jiang
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK 74078, USA.
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165
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Zhang X, Zheng Y, Jagadeeswaran G, Ren R, Sunkar R, Jiang H. Identification of conserved and novel microRNAs in Manduca sexta and their possible roles in the expression regulation of immunity-related genes. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2014; 47:12-22. [PMID: 24508515 PMCID: PMC3992939 DOI: 10.1016/j.ibmb.2014.01.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2013] [Revised: 01/22/2014] [Accepted: 01/26/2014] [Indexed: 05/11/2023]
Abstract
The tobacco hornworm Manduca sexta has served as a model for insect biochemical and physiological research for decades. However, knowledge of the posttranscriptional regulation of gene expression by microRNAs is still rudimentary in this species. Our previous study (Zhang et al., 2012) identified 163 conserved and 13 novel microRNAs in M. sexta, most of which were present at low levels in pupae. To identify additional M. sexta microRNAs and more importantly to examine their possible roles in the expression regulation of immunity-related genes, we constructed four small RNA libraries using fat body and hemocytes from naïve or bacteria-injected larvae and obtained 32.9 million reads of 18-31 nucleotides by Illumina sequencing. Mse-miR-929 and mse-miR-1b (antisense microRNA of mse-miR-1) were predicted in the previous study and now found to be conserved microRNAs in the tissue samples. We also found four novel microRNAs, two of which result from a gene cluster. Mse-miR-281-star, mse-miR-965-star, mse-miR-31-star, and mse-miR-9b-star were present at higher levels than their respective mature strands. Abundance changes of microRNAs were observed after the immune challenge. Based on the quantitative data of mRNA levels in control and induced fat body and hemocytes as well as the results of microRNA target site prediction, we suggest that certain microRNAs and microRNA*s regulate gene expression for pattern recognition, prophenoloxidase activation, cellular responses, antimicrobial peptide synthesis, and conserved intracellular signal transduction (Toll, IMD, JAK-STAT, MAPK-JNK-p38, and small interfering RNA pathways). In summary, this study has enriched our knowledge on M. sexta microRNAs and how some of them may participate in the expression regulation of immunity-related genes.
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Affiliation(s)
- Xiufeng Zhang
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK 74078, USA.
| | - Yun Zheng
- School of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan 650500, China.
| | - Guru Jagadeeswaran
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078, USA.
| | - Ren Ren
- School of Life Sciences, Fudan University, Shanghai 200433, China.
| | - Ramanjulu Sunkar
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078, USA.
| | - Haobo Jiang
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK 74078, USA.
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166
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Zhang S, Cao X, He Y, Hartson S, Jiang H. Semi-quantitative analysis of changes in the plasma peptidome of Manduca sexta larvae and their correlation with the transcriptome variations upon immune challenge. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2014; 47:46-54. [PMID: 24565606 PMCID: PMC3992937 DOI: 10.1016/j.ibmb.2014.02.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2013] [Revised: 02/04/2014] [Accepted: 02/05/2014] [Indexed: 05/23/2023]
Abstract
The tobacco hornworm, Manduca sexta, has been used as a biochemical model for studying insect physiological processes. While the transcriptomes of its fat body, hemocytes, midgut, and antennae have been examined in several studies, limited information is available for proteins in tissues, cells, or body fluids of this insect. In keeping pace with the M. sexta genome project, we launched a pilot study to identify differences in the peptidome of cell-free hemolymph samples from larvae injected with buffer or a mixture of bacteria. At 24 h after injection, plasma was collected and treated with 50% acetonitrile to precipitate large proteins. The supernatants, containing peptides (<25 kDa) and other stable proteins (>25 kDa), were digested with trypsin and analyzed by nano-liquid chromatography and nano-electrospray tandem mass spectrometry (nanoLC-MS/MS) on an LTQ Orbitrap XL mass spectrometer. Known M. sexta cDNA sequences and gene transcripts from the draft genome were translated in silico to generate a database of polypeptides (i.e. peptides and proteins) in this species. By searching the database, we identified 268 hemolymph polypeptides, 50 of which showed 1.67-200 fold abundance increases after the immune challenge, as judged by significant changes in normalized spectral counts between the control and induced plasma. These included a total of 33 antimicrobial peptides (attacins, cecropins, defensins, diapausins, gallerimycin, gloverin, lebocins, lysozymes), pattern recognition receptors, and proteinase inhibitors. Although there was no strong parallel (correlation coefficients: -0.13, 0.11, 0.39 and 0.62) between plasma peptide levels and their transcript levels in control or induced hemocytes or fat body, we observed the mRNA level changes in hemocytes and fat body concurred with their peptide level changes with correlation coefficients of 0.67 and 0.76, respectively. These data suggest that fat body contributed a significant portion of the plasma polypeptides involved in various aspects of innate immunity after the bacterial injection.
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Affiliation(s)
- Shuguang Zhang
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Xiaolong Cao
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Yan He
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Steve Hartson
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Haobo Jiang
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK 74078, USA.
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167
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Freitak D, Schmidtberg H, Dickel F, Lochnit G, Vogel H, Vilcinskas A. The maternal transfer of bacteria can mediate trans-generational immune priming in insects. Virulence 2014; 5:547-54. [PMID: 24603099 DOI: 10.4161/viru.28367] [Citation(s) in RCA: 113] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Parents invest in their offspring by preparing them for defense against pathogens and parasites that only the parents have encountered, a phenomenon known as trans-generational immune priming. We investigated the underlying mechanism using the established lepidopteran model host Galleria mellonella. When larvae were fed with non-pathogenic bacteria, or the entomopathogenic species Pseudomonas entomophila and Serratia entomophila, the activity of lysozyme and phenoloxidase increased in the hemolymph, and immunity-related genes encoding antibacterial proteins such as gloverin were induced. Remarkably, the ingestion of bacteria by female larvae resulted in the differential expression of immunity-related genes in the eggs subsequently laid by the same females, providing evidence for trans-generational immune priming in G. mellonella. To determine the fate of these ingested microbes, the larval diet was supplemented with bacteria carrying a fluorescent label. We observed these bacteria crossing the midgut epithelium, their entrapment within nodules in the hemocoel, their accumulation within the ovary, and ultimately their deposition in the eggs. Therefore, we propose that trans-generational immune priming in Lepidoptera can be mediated by the maternal transfer of bacteria or bacterial fragments to the developing eggs.
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Affiliation(s)
- Dalial Freitak
- Department of Applied Entomology; Institute for Phytopathology and Applied Entomology; Justus Liebig University; Giessen, Germany
| | - Henrike Schmidtberg
- Department of Applied Entomology; Institute for Phytopathology and Applied Entomology; Justus Liebig University; Giessen, Germany
| | - Franziska Dickel
- Department of Applied Entomology; Institute for Phytopathology and Applied Entomology; Justus Liebig University; Giessen, Germany
| | - Günther Lochnit
- Institute of Biochemistry; Justus Liebig University; Giessen, Germany
| | - Heiko Vogel
- Department of Entomology; Max Planck Institute for Chemical Ecology; Jena, Germany
| | - Andreas Vilcinskas
- Department of Applied Entomology; Institute for Phytopathology and Applied Entomology; Justus Liebig University; Giessen, Germany
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168
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Vogel H, Badapanda C, Knorr E, Vilcinskas A. RNA-sequencing analysis reveals abundant developmental stage-specific and immunity-related genes in the pollen beetle Meligethes aeneus. INSECT MOLECULAR BIOLOGY 2014; 23:98-112. [PMID: 24252113 DOI: 10.1111/imb.12067] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The pollen beetle (Meligethes aeneus) is a major pest of oilseed rape (Brassica napus) and other cruciferous crops in Europe. Pesticide-resistant pollen beetle populations are emerging, increasing the economic impact of this species. We isolated total RNA from the larval and adult stages, the latter either naïve or immunized by injection with bacteria and yeast. High-throughput RNA sequencing (RNA-Seq) was carried out to establish a comprehensive transcriptome catalogue and to screen for developmental stage-specific and immunity-related transcripts. We assembled the transcriptome de novo by combining sequence tags from all developmental stages and treatments. Gene expression data based on normalized read counts revealed several functional gene categories that were differentially expressed between larvae and adults, particularly genes associated with digestion and detoxification that were induced in larvae, and genes associated with reproduction and environmental signalling that were induced in adults. We also identified many genes associated with microbe recognition, immunity-related signalling and defence effectors, such as antimicrobial peptides (AMPs) and lysozymes. Digital gene expression analysis revealed significant differences in the profile of AMPs expressed in larvae, naïve adults and immune-challenged adults, providing insight into the steady-state differences between developmental stages and the complex transcriptional remodelling that occurs following the induction of immunity. Our data provide insight into the adaptive mechanisms used by phytophagous insects and could lead to the development of more effective control strategies for insect pests.
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Affiliation(s)
- H Vogel
- Department of Entomology, Max Planck Institute for Chemical Ecology, Jena, Germany
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169
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Liu Y, Shen D, Zhou F, Wang G, An C. Identification of immunity-related genes in Ostrinia furnacalis against entomopathogenic fungi by RNA-seq analysis. PLoS One 2014; 9:e86436. [PMID: 24466095 PMCID: PMC3895045 DOI: 10.1371/journal.pone.0086436] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2013] [Accepted: 12/10/2013] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND The Asian corn borer (Ostrinia furnacalis (Guenée)) is one of the most serious corn pests in Asia. Control of this pest with entomopathogenic fungus Beauveria bassiana has been proposed. However, the molecular mechanisms involved in the interactions between O. furnacalis and B. bassiana are unclear, especially under the conditions that the genomic information of O. furnacalis is currently unavailable. So we sequenced and characterized the transcriptome of O. furnacalis larvae infected by B. bassiana with special emphasis on immunity-related genes. METHODOLOGY/PRINCIPAL FINDINGS Illumina Hiseq2000 was used to sequence 4.64 and 4.72 Gb of the transcriptome from water-injected and B. bassiana-injected O. furnacalis larvae, respectively. De novo assembly generated 62,382 unigenes with mean length of 729 nt. All unigenes were searched against Nt, Nr, Swiss-Prot, COG, and KEGG databases for annotations using BLASTN or BLASTX algorithm with an E-value cut-off of 10(-5). A total of 35,700 (57.2%) unigenes were annotated to at least one database. Pairwise comparisons resulted in 13,890 differentially expressed genes, with 5,843 up-regulated and 8,047 down-regulated. Based on sequence similarity to homologs known to participate in immune responses, we totally identified 190 potential immunity-related unigenes. They encode 45 pattern recognition proteins, 33 modulation proteins involved in the prophenoloxidase activation cascade, 46 signal transduction molecules, and 66 immune responsive effectors, respectively. The obtained transcriptome contains putative orthologs for nearly all components of the Toll, Imd, and JAK/STAT pathways. We randomly selected 24 immunity-related unigenes and investigated their expression profiles using quantitative RT-PCR assay. The results revealed variant expression patterns in response to the infection of B. bassiana. CONCLUSIONS/SIGNIFICANCE This study provides the comprehensive sequence resource and expression profiles of the immunity-related genes of O. furnacalis. The obtained data gives an insight into better understanding the molecular mechanisms of innate immune processes in O. furnacalis larvae against B. bassiana.
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Affiliation(s)
- Yang Liu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Dongxu Shen
- Department of Entomology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, China
| | - Fan Zhou
- Department of Entomology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, China
| | - Guirong Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Chunju An
- Department of Entomology, College of Agriculture and Biotechnology, China Agricultural University, Beijing, China
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170
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Shi M, Chen XY, Zhu N, Chen XX. Molecular identification of two prophenoloxidase-activating proteases from the hemocytes of Plutella xylostella (Lepidoptera: Plutellidae) and their transcript abundance changes in response to microbial challenges. JOURNAL OF INSECT SCIENCE (ONLINE) 2014; 14:179. [PMID: 25399433 PMCID: PMC5633980 DOI: 10.1093/jisesa/ieu041] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Accepted: 05/08/2013] [Indexed: 06/01/2023]
Abstract
The phenoloxidase (PO) activation system plays an important role in insect innate immunity, particularly in wound healing and pathogen defense. A key member of this system is prophenoloxidase-activating protease (PAP), which is the direct activator of prophenoloxidase (proPO). Despite their importance in the insect PO activation system, content of studies is limited. In this article, we identify two complementary DNAs (cDNAs), PxPAPa and PxPAPb, encoding possible PAPs, from immunized larval hemocytes of the diamondback moth, Plutella xylostella (L.), by RACE method. PxPAPa is 1,149-bp long and encodes a 382-residue open reading frame (ORF) with a predicted 17-residue signal peptide, a clip domain, and a Tryp_Spc domain. PxPAPb is 1,650-bp long and encodes a 440-residue ORF with a predicted 20-residue signal peptide, two clip domains, and a Tryp_Spc domain. PxPAPa and PxPAPb have a high sequence similarity to Manduca sexta (L.) PAP1 and PAP3, respectively. We also examined the transcript patterns of PxPAPa, PxPAPb, and pxPAP3, another clip-domain serine protease gene, response to different microbial challenges by using real-time quantitative polymerase chain reaction. The results show that the transcript abundance of PxPAPa is significantly increased by Micrococcus luteus and Escherichia coli but not Candida albicans. PxPAPb is induced only by Mi. luteus, whereas pxPAP3 could be induced by all the microbes in the test, but the transcript patterns of Mi. luteus, E. coli, and C. albicans are completely different. This study provides new insights into the molecular events that occur during the immune response, particularly melanization cascade that is involved in encapsulation and nodulation of pathogen or parasite invaders via hemocytes in host insects.
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Affiliation(s)
- Min Shi
- Ministry of Agriculture Key Lab of Agricultural Entomology, Institute of Insect Sciences, Zhejiang University, 866 Yuhangtang Rd., Hangzhou 310058, China
| | - Xiao-Yu Chen
- Ministry of Agriculture Key Lab of Agricultural Entomology, Institute of Insect Sciences, Zhejiang University, 866 Yuhangtang Rd., Hangzhou 310058, China
| | - Ni Zhu
- Ministry of Agriculture Key Lab of Agricultural Entomology, Institute of Insect Sciences, Zhejiang University, 866 Yuhangtang Rd., Hangzhou 310058, China
| | - Xue-Xin Chen
- Ministry of Agriculture Key Lab of Agricultural Entomology, Institute of Insect Sciences, Zhejiang University, 866 Yuhangtang Rd., Hangzhou 310058, China
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171
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Ghani IA, Dieng H, Abu Hassan ZA, Ramli N, Kermani N, Satho T, Ahmad H, Abang FB, Fukumitsu Y, Ahmad AH. Pathogenicity of a microsporidium isolate from the diamondback moth against Noctuid moths: characterization and implications for microbiological pest management. PLoS One 2013; 8:e81642. [PMID: 24349104 PMCID: PMC3859509 DOI: 10.1371/journal.pone.0081642] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2013] [Accepted: 10/15/2013] [Indexed: 12/31/2022] Open
Abstract
Background Due to problems with chemical control, there is increasing interest in the use of microsporidia for control of lepidopteran pests. However, there have been few studies to evaluate the susceptibility of exotic species to microsporidia from indigenous Lepidoptera. Methodology/Principal Findings We investigated some biological characteristics of the microsporidian parasite isolated from wild Plutella xylostella (PX) and evaluated its pathogenicity on the laboratory responses of sympatric invasive and resident noctuid moths. There were significant differences in spore size and morphology between PX and Spodoptera litura (SL) isolates. Spores of PX isolate were ovocylindrical, while those of SL were oval. PX spores were 1.05 times longer than those of SL, which in turn were 1.49 times wider than those of the PX. The timing of infection peaks was much shorter in SL and resulted in earlier larval death. There were no noticeable differences in amplicon size (two DNA fragments were each about 1200 base pairs in length). Phylogenetic analysis revealed that the small subunit (SSU) rRNA gene sequences of the two isolates shared a clade with Nosema/Vairimorpha sequences. The absence of octospores in infected spodopteran tissues suggested that PX and SL spores are closely related to Nosema plutellae and N. bombycis, respectively. Both SL and S. exigua (SE) exhibited susceptibility to the PX isolate infection, but showed different infection patterns. Tissular infection was more diverse in the former and resulted in much greater spore production and larval mortality. Microsporidium-infected larvae pupated among both infected and control larvae, but adult emergence occurred only in the second group. Conclusion/Significance The PX isolate infection prevented completion of development of most leafworm and beet armyworm larvae. The ability of the microsporidian isolate to severely infect and kill larvae of both native and introduced spodopterans makes it a valuable candidate for biocontrol against lepidopteran pests.
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Affiliation(s)
- Idris Abd Ghani
- Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Malaysia
| | - Hamady Dieng
- School of Biological Sciences, Universiti Sains Malaysia, Penang, Malaysia
- * E-mail:
| | | | - Norazsida Ramli
- Department of Biomedical Science, Islamic University of Malaysia, Pahang, Malaysia
| | - Nadia Kermani
- Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Malaysia
| | - Tomomitsu Satho
- Faculty of Pharmaceutical Sciences, Fukuoka University, Japan
| | - Hamdan Ahmad
- School of Biological Sciences, Universiti Sains Malaysia, Penang, Malaysia
| | - Fatimah Bt Abang
- Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, Kuching, Malaysia
| | - Yuki Fukumitsu
- Faculty of Pharmaceutical Sciences, Fukuoka University, Japan
| | - Abu Hassan Ahmad
- School of Biological Sciences, Universiti Sains Malaysia, Penang, Malaysia
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172
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Wetsaphan N, Rimphanitchayakit V, Tassanakajon A, Somboonwiwat K. PmSERPIN3 from black tiger shrimp Penaeus monodon is capable of controlling the proPO system. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2013; 41:110-119. [PMID: 23660411 DOI: 10.1016/j.dci.2013.04.022] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Revised: 04/26/2013] [Accepted: 04/27/2013] [Indexed: 06/02/2023]
Abstract
Serpin or serine proteinase inhibitor is a family of protease inhibitors that are involved in controlling the proteolytic cascade in various biological processes. In shrimp, several serpins have been identified but only a few have been characterized. Herein, the PmSERPIN3 gene identified from Penaeus monodon EST database was studied. By using the 5'- and 3'-Rapid Amplification of cDNA Ends (RACE) techniques, the full-length of PmSERPIN3 cDNA was obtained. The cDNA contained an open reading frame of 1233 bp encoding for 410 amino acid residue protein. Genome sequence analysis revealed that the PmSERPIN3 was an intronless gene. RT-PCR analysis revealed that it was constitutively expressed in all developmental stages, all shrimp tissues tested, and upon pathogen infections. The recombinant mature PmSERPIN3 protein (rPmSERPIN3) produced in Escherichia coli exhibited inhibitory activity against subtilisin. The rPmSERPIN3 also inhibited the shrimp prophenoloxidase system activation in vitro. Injecting the rPmSERPIN3 along with Vibrio harveyi into the shrimp decreased the clearance rate of bacteria in the hemolymph. Potentially, the PmSERPIN3 functions as a regulator of the proPO activating system.
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Affiliation(s)
- Natthiya Wetsaphan
- Center of Excellence for Molecular Biology and Genomics of Shrimp, Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
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173
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Hemocyte density increases with developmental stage in an immune-challenged forest caterpillar. PLoS One 2013; 8:e70978. [PMID: 23940679 PMCID: PMC3735507 DOI: 10.1371/journal.pone.0070978] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 06/25/2013] [Indexed: 01/11/2023] Open
Abstract
The cellular arm of the insect immune response is mediated by the activity of hemocytes. While hemocytes have been well-characterized morphologically and functionally in model insects, few studies have characterized the hemocytes of non-model insects. Further, the role of ontogeny in mediating immune response is not well understood in non-model invertebrate systems. The goals of the current study were to (1) determine the effects of caterpillar size (and age) on hemocyte density in naïve caterpillars and caterpillars challenged with non-pathogenic bacteria, and (2) characterize the hemocyte activity and diversity of cell types present in two forest caterpillars: Euclea delphinii and Lithacodes fasciola (Limacodidae). We found that although early and late instar (small and large size, respectively) naïve caterpillars had similar constitutive hemocyte densities in both species, late instar Lithacodes caterpillars injected with non-pathogenic E. coli produced more than a twofold greater density of hemocytes than those in early instars. We also found that both caterpillar species contained plasmatocytes, granulocytes and oenocytoids, all of which are found in other lepidopteran species, but lacked spherulocytes. Granulocytes and plasmatocytes were found to be strongly phagocytic in both species, but granulocytes exhibited a higher phagocytic activity than plasmatocytes. Our results strongly suggest that for at least one measure of immunological response, the production of hemocytes in response to infection, response magnitudes can increase over ontogeny. While the underlying raison d’ être for this improvement remains unclear, these findings may be useful in explaining natural patterns of stage-dependent parasitism and pathogen infection.
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174
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Increase in gut microbiota after immune suppression in baculovirus-infected larvae. PLoS Pathog 2013; 9:e1003379. [PMID: 23717206 PMCID: PMC3662647 DOI: 10.1371/journal.ppat.1003379] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Accepted: 04/05/2013] [Indexed: 02/04/2023] Open
Abstract
Spodoptera exigua microarray was used to determine genes differentially expressed in S. exigua cells challenged with the species-specific baculovirus SeMNPV as well as with a generalist baculovirus, AcMNPV. Microarray results revealed that, in contrast to the host transcriptional shut-off that is expected during baculovirus infection, S. exigua cells showed a balanced number of up- and down-regulated genes during the first 36 hours following the infection. Many immune-related genes, including pattern recognition proteins, genes involved in signalling and immune pathways as well as immune effectors and genes coding for proteins involved in the melanization cascade were found to be down-regulated after baculovirus infection. The down-regulation of immune-related genes was confirmed in the larval gut. The expression of immune-related genes in the gut is known to affect the status of gut microorganisms, many of which are responsible for growth and development functions. We therefore asked whether the down-regulation that occurs after baculovirus infection affects the amount of gut microbiota. An increase in the gut bacterial load was observed and we hypothesize this to be as a consequence of viral infection. Subsequent experiments on virus performance in the presence and absence of gut microbiota revealed that gut bacteria enhanced baculovirus virulence, pathogenicity and dispersion. We discuss the host immune response processes and pathways affected by baculoviruses, as well as the role of gut microbiota in viral infection. Baculoviruses are large DNA viruses that infect invertebrates, mainly insects from the order Lepidoptera. They were first discovered to cause insects' epizootics and are now used worldwide as biocontrol agents. Extensive studies on baculovirus biology led to the discovery that they can serve as expression vectors in insect cells; recently they have also been considered as vectors for gene therapy. Baculovirus infection, like many other oral infections, starts with the invasion of the gut by viruses; the gut is a compartment colonized by a community of resident microbiota. In this study, we observed that baculovirus infection leads to the decreased expression of immune-related genes in a Spodoptera exigua cell culture as well as in the larval gut. Gut microbial loads were found to increase after baculovirus infection. A series of bioassays showed that the baculovirus performs better in the presence of microbiota in the gut. Our study shows that baculovirus infection leads to increase of microbiota loads in the gut and that the gut microbiota play a significant role in insect immunity and susceptibility to viral infections. These findings suggest that gut microbiota can be manipulated to improve biocontrol strategies that employ baculoviruses.
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175
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Gunaratna RT, Jiang H. A comprehensive analysis of the Manduca sexta immunotranscriptome. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2013; 39. [PMID: 23178408 PMCID: PMC3595354 DOI: 10.1016/j.dci.2012.10.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
As a biochemical model, Manduca sexta has substantially contributed to our knowledge on insect innate immunity. The RNA-Seq approach was implemented in three studies to examine tissue immunotranscriptomes of this species. With the latest and largest focusing on highly regulated process- and tissue-specific genes, we further analyzed the same set of data using BLAST2GO to explore functional aspects of the larval fat body (F) and hemocyte (H) transcriptomes with (I) or without (C) immune challenge. Using immunity-related sequences from other insects, we found 383 homologous contigs and compared them with those discovered based on relative abundance changes. The major overlap of the two lists validated our previous research designed for gene discovery and transcript profiling in organisms lacking sequenced genomes. By concatenating the contigs, we established a repertoire of 232 immunity-related genes encoding proteins for pathogen recognition (16%), signal transduction (53%), microbe killing (13%) and others (18%). We examined their transcript levels along with attribute classifications and detected prominent differences in nine of the 30 level 2 gene ontology (GO) categories. The increase in extracellular proteins (155%) was consistent with the highly induced synthesis of defense molecules (e.g., antimicrobial peptides) in fat body after the immune challenge. We identified most members of the putative Toll, IMD, MAPK-JNK-p38 and JAK-STAT pathways and small changes in their mRNA levels. Together, these findings set the stage for on-going analysis of the M. sexta immunogenome.
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Affiliation(s)
- Ramesh T Gunaratna
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK 74078, USA
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176
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Grigorian M, Hartenstein V. Hematopoiesis and hematopoietic organs in arthropods. Dev Genes Evol 2013; 223:103-15. [PMID: 23319182 PMCID: PMC3873168 DOI: 10.1007/s00427-012-0428-2] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2012] [Accepted: 10/22/2012] [Indexed: 01/04/2023]
Abstract
Hemocytes (blood cells) are motile cells that move throughout the extracellular space and that exist in all clades of the animal kingdom. Hemocytes play an important role in shaping the extracellular environment and in the immune response. Developmentally, hemocytes are closely related to the epithelial cells lining the vascular system (endothelia) and the body cavity (mesothelia). In vertebrates and insects, common progenitors, called hemangioblasts, give rise to the endothelia and blood cells. In the adult animal, many differentiated hemocytes seem to retain the ability to proliferate; however, in most cases investigated closely, the bulk of hemocyte proliferation takes place in specialized hematopoietic organs. Hematopoietic organs provide an environment where undifferentiated blood stem cells are able to self-renew, and at the same time generate offspring that differentiate into different blood cell types. Hematopoiesis in vertebrates, taking place in the bone marrow, has been subject to intensive research by immunologists and stem cell biologists. Much less is known about blood cell formation in invertebrate animals. In this review, we will survey structural and functional properties of invertebrate hematopoietic organs, with a main focus on insects and other arthropod taxa. We will then discuss similarities, at the molecular and structural level, that are apparent when comparing the development of blood cells in hematopoietic organs of vertebrates and arthropods. Our comparative review is intended to elucidate aspects of the biology of blood stem cells that are more easily missed when focusing on one or a few model species.
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Affiliation(s)
- Melina Grigorian
- Department of Molecular Cell and Developmental Biology, University of California Los Angeles, Los Angeles, CA 90095, USA
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177
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Mukherjee K, Hain T, Fischer R, Chakraborty T, Vilcinskas A. Brain infection and activation of neuronal repair mechanisms by the human pathogen Listeria monocytogenes in the lepidopteran model host Galleria mellonella. Virulence 2013; 4:324-32. [PMID: 23348912 PMCID: PMC3710335 DOI: 10.4161/viru.23629] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Listeria monocytogenes the causative agent of the foodborne disease listeriosis in humans often involves fatal brainstem infections leading to meningitis and meningoencephalitis. We recently established the larvae of the greater wax moth (Galleria mellonella) as a model host for the investigation of L. monocytogenes pathogenesis and as a source of peptides exhibiting anti-Listeria-activity. Here we show that G. mellonella can be used to study brain infection and its impact on larval development as well as the activation of stress responses and neuronal repair mechanisms. The infection of G. mellonella larvae with L. monocytogenes elicits a cellular immune response involving the formation of melanized cellular aggregates (nodules) containing entrapped bacteria. These form under the integument and in the brain, resembling the symptoms found in human patients. We screened the G. mellonella transcriptome with marker genes representing stress responses and neuronal repair, and identified several modulated genes including those encoding heat shock proteins, growth factors, and regulators of neuronal stress. Remarkably, we discovered that L. monocytogenes infection leads to developmental shift in larvae and also modulates the expression of genes involved in the regulation of endocrine functions. We demonstrated that L. monocytogenes pathogenesis can be prevented by treating G. mellonella larvae with signaling inhibitors such as diclofenac, arachidonic acid, and rapamycin. Our data extend the utility of G. mellonella larvae as an ideal model for the high-throughput in vivo testing of potential compounds against listeriosis.
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Affiliation(s)
- Krishnendu Mukherjee
- Institute of Phytopathology and Applied Zoology, Justus-Liebig-University of Giessen, Giessen, Germany
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178
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Ligoxygakis P. Genetics of Immune Recognition and Response in Drosophila host defense. ADVANCES IN GENETICS 2013; 83:71-97. [DOI: 10.1016/b978-0-12-407675-4.00002-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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179
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Zhou Y, Wu S, Wang H, Hayakawa Y, Bird GS, Shears SB. Activation of PLC by an endogenous cytokine (GBP) in Drosophila S3 cells and its application as a model for studying inositol phosphate signalling through ITPK1. Biochem J 2012; 448:273-83. [PMID: 22928859 PMCID: PMC3925326 DOI: 10.1042/bj20120730] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Using immortalized [3H]inositol-labelled S3 cells, we demonstrated in the present study that various elements of the inositol phosphate signalling cascade are recruited by a Drosophila homologue from a cytokine family of so-called GBPs (growth-blocking peptides). HPLC analysis revealed that dGBP (Drosophila GBP) elevated Ins(1,4,5)P3 levels 9-fold. By using fluorescent Ca2+ probes, we determined that dGBP initially mobilized Ca2+ from intracellular pools; the ensuing depletion of intracellular Ca2+ stores by dGBP subsequently activated a Ca2+ entry pathway. The addition of dsRNA (double-stranded RNA) to knock down expression of the Drosophila Ins(1,4,5)P3 receptor almost completely eliminated mobilization of intracellular Ca2+ stores by dGBP. Taken together, the results of the present study describe a classical activation of PLC (phospholipase C) by dGBP. The peptide also promoted increases in the levels of other inositol phosphates with signalling credentials: Ins(1,3,4,5)P4, Ins(1,4,5,6)P4 and Ins(1,3,4,5,6)P5. These results greatly expand the regulatory repertoire of the dGBP family, and also characterize S3 cells as a model for studying the regulation of inositol phosphate metabolism and signalling by endogenous cell-surface receptors. We therefore created a cell-line (S3ITPK1) in which heterologous expression of human ITPK (inositol tetrakisphosphate kinase) was controlled by an inducible metallothionein promoter. We found that dGBP-stimulated S3ITPK1 cells did not synthesize Ins(3,4,5,6)P4, contradicting a hypothesis that the PLC-coupled phosphotransferase activity of ITPK1 [Ins(1,3,4,5,6)P5+Ins(1,3,4)P3→Ins(3,4,5,6)P4+Ins(1,3,4,6)P4] is driven solely by the laws of mass action [Chamberlain, Qian, Stiles, Cho, Jones, Lesley, Grabau, Shears and Spraggon (2007) J. Biol. Chem. 282, 28117-28125]. This conclusion represents a fundamental breach in our understanding of ITPK1 signalling.
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Affiliation(s)
- Yixing Zhou
- Inositol Signaling Section, Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC 27709, U.S.A
| | - Shilan Wu
- Calcium Regulation Section, Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC 27709, U.S.A
| | - Huanchen Wang
- Inositol Signaling Section, Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC 27709, U.S.A
| | - Yoichi Hayakawa
- Department of Applied Biological Sciences, Saga University, Honjo-1, Saga 840-8502, Japan
| | - Gary S. Bird
- Calcium Regulation Section, Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC 27709, U.S.A
| | - Stephen B. Shears
- Inositol Signaling Section, Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC 27709, U.S.A
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180
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Stoepler TM, Castillo JC, Lill JT, Eleftherianos I. A simple protocol for extracting hemocytes from wild caterpillars. J Vis Exp 2012. [PMID: 23183567 DOI: 10.3791/4173] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Insect hemocytes (equivalent to mammalian white blood cells) play an important role in several physiological processes throughout an insect's life cycle. In larval stages of insects belonging to the orders of Lepidoptera (moths and butterflies) and Diptera (true flies), hemocytes are formed from the lymph gland (a specialized hematopoietic organ) or embryonic cells and can be carried through to the adult stage. Embryonic hemocytes are involved in cell migration during development and chemotaxis regulation during inflammation. They also take part in cell apoptosis and are essential for embryogenesis. Hemocytes mediate the cellular arm of the insect innate immune response that includes several functions, such as cell spreading, cell aggregation, formation of nodules, phagocytosis and encapsulation of foreign invaders. They are also responsible for orchestrating specific insect humoral defenses during infection, such as the production of antimicrobial peptides and other effector molecules. Hemocyte morphology and function have mainly been studied in genetic or physiological insect models, including the fruit fly, Drosophila melanogaster, the mosquitoes Aedes aegypti and Anopheles gambiae and the tobacco hornworm, Manduca sexta. However, little information currently exists about the diversity, classification, morphology and function of hemocytes in non-model insect species, especially those collected from the wild. Here we describe a simple and efficient protocol for extracting hemocytes from wild caterpillars. We use penultimate instar Lithacodes fasciola (yellow-shouldered slug moth) (Figure 1) and Euclea delphinii (spiny oak slug) caterpillars (Lepidoptera: Limacodidae) and show that sufficient volumes of hemolymph (insect blood) can be isolated and hemocyte numbers counted from individual larvae. This method can be used to efficiently study hemocyte types in these species as well as in other related lepidopteran caterpillars harvested from the field, or it can be readily combined with immunological assays designed to investigate hemocyte function following infection with microbial or parasitic organisms.
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181
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Li F, Terenius O, Li Y, Fang S, Li W. cDNA Cloning and Expression Analysis of Pattern Recognition Proteins from the Chinese Oak Silkmoth, Antheraea pernyi. INSECTS 2012; 3:1093-104. [PMID: 26466728 PMCID: PMC4553565 DOI: 10.3390/insects3041093] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2012] [Revised: 10/12/2012] [Accepted: 10/15/2012] [Indexed: 12/02/2022]
Abstract
Pattern recognition receptors play an important role in insect immune defense. We cloned the β-1,3-glucan recognition protein, lectin-5 and C-type lectin 1 genes of Antheraea pernyi and examined the expression profiles of immune-stimulated pupae. After infection with Bacillus subtilis, Escherichia coli, Antheraea pernyi nuclear polyhedrosis virus (ApNPV) and Saccharomyces cerevisiae, respectively, the pupae showed different gene expression levels in the different tissues examined (midgut, fatbody, epidermis, testis, and hemocytes). ApβGRP and Aplectin-5 was induced by all the microorganisms, and mainly in epidermis and hemocytes, but not in testis; Aplectin-5 was also expressed in fatbody. Ap C-type lectin 1 was, on the contrary, highly expressed in testis and also in fatbody, but not in hemocytes. Unlike ApβGRP and Aplectin-5, Ap C-type lectin 1 was not induced by Gram-positive bacteria. The results suggest that the cloned lectins may have different functions in different tissues of A. pernyi.
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Affiliation(s)
- Fengjuan Li
- School of Life science and Biotechnology, Dalian University of Technology, Dalian, 116023 Liaoning, China.
| | - Olle Terenius
- Department of Ecology, Swedish University of Agricultural Sciences (SLU), 750 07 Uppsala, Sweden.
| | - Yuan Li
- School of Life science and Biotechnology, Dalian University of Technology, Dalian, 116023 Liaoning, China.
| | - Suyun Fang
- School of Life science and Biotechnology, Dalian University of Technology, Dalian, 116023 Liaoning, China.
| | - Wenli Li
- School of Life science and Biotechnology, Dalian University of Technology, Dalian, 116023 Liaoning, China.
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182
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Choi YJ, Fuchs JF, Mayhew GF, Yu HE, Christensen BM. Tissue-enriched expression profiles in Aedes aegypti identify hemocyte-specific transcriptome responses to infection. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2012; 42:729-38. [PMID: 22796331 PMCID: PMC3438353 DOI: 10.1016/j.ibmb.2012.06.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2012] [Revised: 06/18/2012] [Accepted: 06/23/2012] [Indexed: 05/16/2023]
Abstract
Hemocytes are integral components of mosquito immune mechanisms such as phagocytosis, melanization, and production of antimicrobial peptides. However, our understanding of hemocyte-specific molecular processes and their contribution to shaping the host immune response remains limited. To better understand the immunophysiological features distinctive of hemocytes, we conducted genome-wide analysis of hemocyte-enriched transcripts, and examined how tissue-enriched expression patterns change with the immune status of the host. Our microarray data indicate that the hemocyte-enriched trascriptome is dynamic and context-dependent. Analysis of transcripts enriched after bacterial challenge in circulating hemocytes with respect to carcass added a dimension to evaluating infection-responsive genes and immune-related gene families. We resolved patterns of transcriptional change unique to hemocytes from those that are likely shared by other immune responsive tissues, and identified clusters of genes preferentially induced in hemocytes, likely reflecting their involvement in cell type specific functions. In addition, the study revealed conserved hemocyte-enriched molecular repertoires, which might be implicated in core hemocyte function by cross-species meta-analysis of microarray expression data from Anopheles gambiae and Drosophila melanogaster.
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Affiliation(s)
| | | | | | | | - Bruce M. Christensen
- Corresponding author. Bruce M. Christensen, Department of Pathobiological Sciences, University of Wisconsin-Madison, 1656 Linden Drive, Madison, WI 53706, USA, Tel: + 1 608 262 3850, Fax: +1 608 262 7420,
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183
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Xu XX, Zhong X, Yi HY, Yu XQ. Manduca sexta gloverin binds microbial components and is active against bacteria and fungi. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2012; 38:275-84. [PMID: 22858411 PMCID: PMC3443299 DOI: 10.1016/j.dci.2012.06.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Revised: 06/11/2012] [Accepted: 06/15/2012] [Indexed: 05/03/2023]
Abstract
Hyalophora gloveri gloverin is a glycine-rich and heat stable antimicrobial protein with activity mainly against Escherichia coli. However, Spodoptera exigua gloverin is active against a Gram-positive bacterium but inactive against E. coli. In this study, we investigated expression profile, binding ability and antimicrobial activity of Manduca sexta gloverin (MsGlv). Msglv transcript was detected in several tissues of naïve larvae with higher levels in the midgut and testis. Expression of Msglv mRNA in larvae was up-regulated by active Spätzle-C108 and peptidoglycans (PGs) of E. coli and Staphylococcus aureus, and the activation was blocked by pre-injection of antibody to M. sexta Toll, suggesting that Msglv expression is regulated by the Toll-Spätzle pathway. Recombinant MsGlv bound to the O-specific antigen and outer core carbohydrate of lipopolysaccharide (LPS), Gram-positive lipoteichoic acid (LTA) and PG, and laminarin, but not to E. coli PG or mannan. MsGlv was active against Bacillus cereus, Saccharomyces cerevisiae and Cryptococcus neoformans, but was almost inactive against E. coli and S. aureus. Our results suggest that gloverins are active against some bacteria and fungi.
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Affiliation(s)
- Xiao-Xia Xu
- Division of Cell Biology and Biophysics, School of Biological Sciences, University of Missouri-Kansas City, Kansas City, MO 64110, USA
- College of Natural Resources and Environments, South China Agricultural University, 483 Wushan Road, Guangzhou 510642, China
| | - Xue Zhong
- Division of Cell Biology and Biophysics, School of Biological Sciences, University of Missouri-Kansas City, Kansas City, MO 64110, USA
| | - Hui-Yu Yi
- Division of Cell Biology and Biophysics, School of Biological Sciences, University of Missouri-Kansas City, Kansas City, MO 64110, USA
- College of Animal Science, South China Agricultural University, 483 Wushan Road, Guangzhou 510642, China
| | - Xiao-Qiang Yu
- Division of Cell Biology and Biophysics, School of Biological Sciences, University of Missouri-Kansas City, Kansas City, MO 64110, USA
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184
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Zhai X, Zhao XF. Participation of haemocytes in fat body degradation via cathepsin L expression. INSECT MOLECULAR BIOLOGY 2012; 21:521-534. [PMID: 22882178 DOI: 10.1111/j.1365-2583.2012.01157.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Insect haemocytes are known to participate in innate immunity via the phagocytosis of pathogens. However, the function of haemocytes in tissue remodelling is less understood. We report here that haemocytes play roles in fat body degradation by expressing a cysteine proteinase cathepsin L in the lepidopteran Helicoverpa armigera. During metamorphosis, haemocytes undergo morphological changes by increasing their cell size and transforming their granulocytes into macrogranulocytes. The population of haemocytes also changes with increased number of granulocytes and decreased plasmatocytes. The expression level of cathepsin L in haemocytes, mainly in granulocytes and plasmatocytes, increases. The steroid hormone 20-hydroxyecdysone is able to promote the transformation of granulocytes into macrogranulocytes, and up-regulate the expression level of cathepsin L. The knock-down of the cathepsin L gene by RNA interference in haemocytes in vitro results in deficient granulocytes transforming into macrogranulocytes. Haemocytes are able to enter the decomposed fat body during metamorphosis. The over-expression of the proteinase domain C1A of cathepsin L results in cell apoptosis. Haemocytes, especially macrogranulocytes, undergo apoptosis and cathepsin L is released into haemolymph and the fat body during metamorphosis for fat body decomposition and degradation. These results suggest that cathepsin L is related to the transformation of granulocytes to macrogranulocytes to enter the fat body, and induce haemocyte apoptosis for further tissue degradation.
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Affiliation(s)
- X Zhai
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Jinan, China
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185
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Somnuk S, Tassanakajon A, Rimphanitchayakit V. Gene expression and characterization of a serine proteinase inhibitor PmSERPIN8 from the black tiger shrimp Penaeus monodon. FISH & SHELLFISH IMMUNOLOGY 2012; 33:332-341. [PMID: 22738762 DOI: 10.1016/j.fsi.2012.05.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2012] [Revised: 04/16/2012] [Accepted: 05/07/2012] [Indexed: 06/01/2023]
Abstract
The ubiquitous SERPINs or serine proteinase inhibitors are essential for controlling proteinases in several biological processes in various organisms. A PmSERPIN8, one of eight SERPINs identified from the Penaeus monodon database, is studied and reported herein. The open reading frame of PmSERPIN8 gene derived from a genomic gene contains 5 exons of 320, 139, 244, 239 and 312 bp separated by 4 introns of 447, 657, 326 and 479 bp. The PmSERPIN8 gene is highly expressed at nauplius stage and gradually subsided as the shrimp grow through zoea, mysis and postlarva stages. At sub-adult stage, the PmSERPIN8 gene is expressed mainly in the hemocyte and epipodite. The expression in response to Vibrio harveyi and YHV injection is up-regulated, respectively, at 24 and 48 h post-injection. The number of PmSERPIN8-producing hemocytes, however, is observed highest at 48 h post V. harveyi injection. All three hemocyte cell types: hyaline, semigranular and granular hemocytes are able to produce PmSERPIN8. The recombinant mature PmSERPIN8 (rPmSERPIN8) with a predicted size of 45.5 kDa was over-produced in an Escherichia coli system, solubilized from the inclusion bodies, purified and tested for its activity. We have found that the rPmSERPIN8 is able to inhibit the growth of Gram-positive bacterium, Bacillus subtilis, but not Gram-negative bacterium, V. harveyi 639, and inhibit the shrimp prophenoloxidase system. The PmSERPIN8 is, thus, involved in the shrimp innate immunity.
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Affiliation(s)
- Suphaphon Somnuk
- Center of Excellence for Molecular Biology and Genomics of Shrimp, Department of Biochemistry, Faculty of Science, Chulalongkorn University, Pathumwan, Bangkok, Thailand
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186
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Zhang X, Zheng Y, Jagadeeswaran G, Ren R, Sunkar R, Jiang H. Identification and developmental profiling of conserved and novel microRNAs in Manduca sexta. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2012; 42:381-95. [PMID: 22406339 PMCID: PMC3340478 DOI: 10.1016/j.ibmb.2012.01.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Revised: 01/08/2012] [Accepted: 01/26/2012] [Indexed: 05/09/2023]
Abstract
MicroRNAs (miRNAs) are a group of small RNAs involved in translation inhibition or mRNA degradation. Due to its large size, Manduca sexta has long been used as a model to study insect physiology and biochemistry. While transcriptome studies have greatly enriched our knowledge on M. sexta structural genes, little is known about posttranscriptional regulation by miRNAs in this lepidopteran species. We constructed four small RNA libraries from embryos, 4th instar feeding larvae, pupae, and adults, obtained 21 million reads of 18-31 nucleotides by Illumina sequencing, and found 163 conserved and 13 novel miRNAs. By searching the M. sexta genome assembly, we identified precursors of 82 conserved miRNAs, 76 of which had mapped reads in one or more of these libraries. After normalization, we compared numbers of miRNA and miRNA-star reads in these libraries and observed abundance changes during development. Interestingly, mse-miR-281-star, mse-miR-31-star, mse-miR-965-star, mse-miR-9a-star, mse-miR-9b-star, mse-miR-2a-star, mse-miR-92b-star and mse-miR-279c-star are either more abundant or maintained at similar levels compared to respective mature miRNA strand. Expression profiling of the first set of miRNAs provided insights to their possible involvement in developmental regulation. This study will aid in the annotation of miRNA genes in the genome.
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Affiliation(s)
- Xiufeng Zhang
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK 74078, USA.
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187
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Nielsen-LeRoux C, Gaudriault S, Ramarao N, Lereclus D, Givaudan A. How the insect pathogen bacteria Bacillus thuringiensis and Xenorhabdus/Photorhabdus occupy their hosts. Curr Opin Microbiol 2012; 15:220-31. [PMID: 22633889 DOI: 10.1016/j.mib.2012.04.006] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Revised: 04/26/2012] [Accepted: 04/27/2012] [Indexed: 10/28/2022]
Abstract
Insects are the largest group of animals on earth. Like mammals, virus, fungi, bacteria and parasites infect them. Several tissue barriers and defense mechanisms are common for vertebrates and invertebrates. Therefore some insects, notably the fly Drosophila and the caterpillar Galleria mellonella, have been used as models to study host-pathogen interactions for several insect and mammal pathogens. They are excellent tools to identify pathogen determinants and host tissue cell responses. We focus here on the comparison of effectors used by two different groups of bacterial insect pathogens to accomplish the infection process in their lepidopteran larval host: Bacillus thuringiensis and the nematode-associated bacteria, Photorhabdus and Xenorhabdus. The comparison reveals similarities in function and expression profiles for some genes, which suggest that such factors are conserved during evolution in order to attack the tissue encountered during the infection process.
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Affiliation(s)
- Christina Nielsen-LeRoux
- INRA, UMR1319, Micalis, Génétique microbienne et Environnement, La Minière, F-78280 Guyancourt, France.
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188
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Davies SA, Overend G, Sebastian S, Cundall M, Cabrero P, Dow JAT, Terhzaz S. Immune and stress response 'cross-talk' in the Drosophila Malpighian tubule. JOURNAL OF INSECT PHYSIOLOGY 2012; 58:488-497. [PMID: 22306292 DOI: 10.1016/j.jinsphys.2012.01.008] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2011] [Revised: 01/10/2012] [Accepted: 01/12/2012] [Indexed: 05/31/2023]
Abstract
The success of insects is in large part due to their ability to survive environmental stress, including heat, cold, and dehydration. Insects are also exposed to infection, osmotic or oxidative stress, and to xenobiotics or toxins. The molecular mechanisms of stress sensing and response have been widely investigated in mammalian cell lines, and the area of stress research is now so vast to be beyond the scope of a single review article. However, the mechanisms by which stress inputs to the organism are sensed and integrated at the tissue and cellular level are less well understood. Increasingly, common molecular events between immune and other stress responses are observed in vivo; and much of this work stems of efforts in insect molecular science and physiology. We describe here the current knowledge in the area of immune and stress signalling and response at the level of the organism, tissue and cell, focussing on a key epithelial tissue in insects, the Malpighian tubule, and drawing together the known pathways that modulate responses to different stress insults. The tubules are critical for insect survival and are increasingly implicated in responses to multiple and distinct stress inputs. Importantly, as tubule function is central to survival, they are potentially key targets for insect control, which will be facilitated by increased understanding of the complexities of stress signalling in the organism.
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Affiliation(s)
- Shireen-Anne Davies
- Institute of Molecular Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK.
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189
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Liu F, Chen Y, Yang B, Wang J, Peng Q, Shao Q, Li X, Beerntsen BT, Xu Y, Li J, Yu XQ, Ling E. Drosophila melanogaster prophenoloxidases respond inconsistently to Cu2+ and have different activity in vitro. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2012; 36:619-628. [PMID: 22178920 DOI: 10.1016/j.dci.2011.12.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2011] [Revised: 11/27/2011] [Accepted: 12/01/2011] [Indexed: 05/31/2023]
Abstract
Dipteran insects, like mosquitoes, possess more than two prophenoloxidase (PPO) genes, but it is unclear whether their gene products differ in biochemical properties and physiological functions. Here, we used three Drosophila melanogaster PPOs as models to study their properties through expression in S2 cells. Our data revealed that the PPOs were expressed in the ethanol-activatable conformation: rPPO1 and rPPO2 needed additional Cu(2+) in the medium, but rPPO3 did not. rPPO1 bound Cu(2+) within minutes; rPPO2 did that in hours when Cu(2+) were present at a higher concentration. Thus, rPPO1 and rPPO2 were expressed as apo-rPPO and became holo-PPO upon Cu(2+) binding; rPPO3 was holo-PPO immediately after expression. Surprisingly, in the absence of ethanol, the apparently intact rPPO3 catalyzed dopamine oxidation and melanization. The successful method for rPPO expression in S2 cells described in this paper will provide us with an opportunity to study the properties of a specific PPO gene in a small insect like mosquitoes in the future.
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Affiliation(s)
- Fei 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
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190
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Moreno-Habel DA, Biglang-awa IM, Dulce A, Luu DD, Garcia P, Weers PMM, Haas-Stapleton EJ. Inactivation of the budded virus of Autographa californica M nucleopolyhedrovirus by gloverin. J Invertebr Pathol 2012; 110:92-101. [PMID: 22401766 DOI: 10.1016/j.jip.2012.02.007] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Revised: 02/09/2012] [Accepted: 02/10/2012] [Indexed: 01/15/2023]
Abstract
Antimicrobial peptides are generated in insects exposed to pathogens for combating infection. Gloverin is a small cationic antibacterial protein whose expression is induced in the hemocytes and fat body cells of Trichoplusia ni larvae exposed to bacteria. The purpose of this study was to determine the role of gloverin during baculovirus infection. We found that gloverin expression is induced in T. ni systemically infected with the baculovirus Autographa californica M nucleopolyhedrovirus (AcMNPV). Two gloverin genes were cloned using RNA isolated from the hemocytes of T. ni larvae that were systemically infected with AcMNPV budded virus (BV) and C-terminal 6x-His and V5 epitope tags were incorporated to facilitate gloverin isolation, detection and functional studies. The supernatants of Sf9 cells stably transfected with the two gloverin expression plasmids and affinity purified gloverin proteins reduced the quantity of infectious AcMNPV BV as measured in vitro by plaque assay with untransfected Sf9 cells. Nanomolar concentrations of affinity column purified gloverin protein caused calcein to be rapidly released from unilamellar vesicles comprised of phosphatidylglycerol, but not from vesicles made up of phosphatidylcholine, suggesting that gloverin interaction with membranes is rapid and affected by membrane charge. Both the BV inactivation and calcein release activities of gloverin increased with higher concentrations of gloverin. These results demonstrate that gloverin is an antiviral protein that interacts with vesicle membranes to cause the contents to be released.
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Affiliation(s)
- Daniela A Moreno-Habel
- Department of Biological Sciences, California State University Long Beach, Long Beach, CA 90840, USA.
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191
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Easom CA, Clarke DJ. HdfR is a regulator in Photorhabdus luminescens that modulates metabolism and symbiosis with the nematode Heterorhabditis. Environ Microbiol 2011; 14:953-66. [DOI: 10.1111/j.1462-2920.2011.02669.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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192
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Vogel H, Badapanda C, Vilcinskas A. Identification of immunity-related genes in the burying beetle Nicrophorus vespilloides by suppression subtractive hybridization. INSECT MOLECULAR BIOLOGY 2011; 20:787-800. [PMID: 21929718 DOI: 10.1111/j.1365-2583.2011.01109.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Burying beetles reproduce on small vertebrate cadavers which they bury in the soil after localization through volatiles emitted from the carcass. They then chemically preserve the carcass and prepare it as a diet for the adults and their offspring. It is predicted that exposure to high loads of soil and/or carrion-associated microbes necessitates an effective immune system. In the present paper, we report experimental screening for immunity-related genes in the burying beetle Nicrophorus vespilloides using the suppression subtractive hybridization approach. A total of 1179 putative gene objects were identified in the Nicrophorus cDNA library, which was enriched for transcripts differentially expressed upon challenge with heat-inactivated bacteria. In addition to genes known to be involved in immunity-related recognition and signalling, we found transcripts encoding for antimicrobial peptides and for an array of enzymes that can be linked to immunity or to stress-induced pathways. We also determined proteins that may contribute to detoxification of toxins produced by microbial competitors. In addition, factors involved in mRNA stability determination and central components of the RNA interference machinery were identified, implying transcriptional reprogramming and potential stress-induced retrotransposon elimination. The identified candidate immune effector and stress-related genes may provide important information about the unusual ecology and evolution of the burying beetles.
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Affiliation(s)
- H Vogel
- Max Planck Institute for Chemical Ecology, Department of Entomology, Jena, Germany
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