51
|
Selot R, Kumar V, Shukla S, Chandrakuntal K, Brahmaraju M, Dandin SB, Laloraya M, Kumar PG. Identification of a Soluble NADPH Oxidoreductase (BmNOX) with Antiviral Activites in the Gut Juice ofBombyx mori. Biosci Biotechnol Biochem 2014; 71:200-5. [PMID: 17213661 DOI: 10.1271/bbb.60450] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Silkworms show high variability in silk quality and disease resistance. Attempts are on to combine the disease tolerance of multivoltine races and the silk quality of bivoltine races to generate new races with desirable phenotypic traits. We report the identification of a 26.5-kDa protein that is overexpressed in the gut juice of disease-resistant multivoltine races and that has anti-BmNPV activity. We have characterized this protein as a soluble NADH-oxidoreductase-like protein (BmNOX). Treatment of live BmNPV particles with BmNOX inhibited the capability of the viral particles to infect BmN cells in vitro.
Collapse
Affiliation(s)
- Ruchita Selot
- Central Sericultural Research and Training Institute, Mysore, India
| | | | | | | | | | | | | | | |
Collapse
|
52
|
Yi HY, Chowdhury M, Huang YD, Yu XQ. Insect antimicrobial peptides and their applications. Appl Microbiol Biotechnol 2014; 98:5807-22. [PMID: 24811407 DOI: 10.1007/s00253-014-5792-6] [Citation(s) in RCA: 346] [Impact Index Per Article: 34.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 04/21/2014] [Accepted: 04/23/2014] [Indexed: 10/25/2022]
Abstract
Insects are one of the major sources of antimicrobial peptides/proteins (AMPs). Since observation of antimicrobial activity in the hemolymph of pupae from the giant silk moths Samia Cynthia and Hyalophora cecropia in 1974 and purification of first insect AMP (cecropin) from H. cecropia pupae in 1980, over 150 insect AMPs have been purified or identified. Most insect AMPs are small and cationic, and they show activities against bacteria and/or fungi, as well as some parasites and viruses. Insect AMPs can be classified into four families based on their structures or unique sequences: the α-helical peptides (cecropin and moricin), cysteine-rich peptides (insect defensin and drosomycin), proline-rich peptides (apidaecin, drosocin, and lebocin), and glycine-rich peptides/proteins (attacin and gloverin). Among insect AMPs, defensins, cecropins, proline-rich peptides, and attacins are common, while gloverins and moricins have been identified only in Lepidoptera. Most active AMPs are small peptides of 20-50 residues, which are generated from larger inactive precursor proteins or pro-proteins, but gloverins (~14 kDa) and attacins (~20 kDa) are large antimicrobial proteins. In this mini-review, we will discuss current knowledge and recent progress in several classes of insect AMPs, including insect defensins, cecropins, attacins, lebocins and other proline-rich peptides, gloverins, and moricins, with a focus on structural-functional relationships and their potential applications.
Collapse
Affiliation(s)
- Hui-Yu Yi
- College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
| | | | | | | |
Collapse
|
53
|
Xia Q, Li S, Feng Q. Advances in silkworm studies accelerated by the genome sequencing of Bombyx mori. ANNUAL REVIEW OF ENTOMOLOGY 2013; 59:513-536. [PMID: 24160415 DOI: 10.1146/annurev-ento-011613-161940] [Citation(s) in RCA: 193] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Significant progress has been achieved in silkworm (Bombyx mori) research since the last review on this insect was published in this journal in 2005. In this article, we review the new and exciting progress and discoveries that have been made in B. mori during the past 10 years, which include the construction of a fine genome sequence and a genetic variation map, the evolution of genomes, the advent of functional genomics, the genetic basis of silk production, metamorphic development, immune response, and the advances in genetic manipulation. These advances, which were accelerated by the genome sequencing project, have promoted B. mori as a model organism not only for lepidopterans but also for general biology.
Collapse
Affiliation(s)
- Qingyou Xia
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400715, China;
| | | | | |
Collapse
|
54
|
Zhang M, Zhou F, Chu Y, Zhao Z, An C. Identification and expression profile analysis of antimicrobial peptide/protein in Asian corn borer, Ostrinia furnacalis (Guenée). Int J Biol Sci 2013; 9:1004-12. [PMID: 24155672 PMCID: PMC3805904 DOI: 10.7150/ijbs.6813] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2013] [Accepted: 07/21/2013] [Indexed: 12/20/2022] Open
Abstract
Antimicrobial peptides/proteins (AMPs) are a group of immune proteins that exhibit strong antibiotic properties against numerous infectious bacterial strains. They are evolutionarily conserved and present in every kingdom and phylum, ranging from prokaryotes to humans. We analyzed the transciptome from the larvae of Asian corn borer, Ostrinia furnacalis (Guenée), and identified several putative AMP transcripts, OfgLys5, OfgLys6, OfgLys10, OfgAtt, and OfgIID. OfgLys5, OfgLys6, and OfgLys10 are all highly homologous with c-type lysozymes, and OfgAtt shows significant identities with Lepidoptera attacin. The amino acid sequence of OfgLys5 and OfgLys6 possessed all conserved features critical for fundamental structure and function of c-type lysozyme, including the two catalytic sites, Glu32 and Asp50. OfgAtt is a typical glycine-rich protein. The antimicrobial activity of O. furnacalis hemolymph increased significantly after injection with Escherichia coli, Micrococcus luteus, or Beauveria bassiana. OfgAtt, IDD, and Lys6 are expressed at low level prior to the challenge, but strongly induced against Gram-positive and negative bacteria, and fungi. Under the same inducement conditions, the transcripts of these three genes elevated most when fifth instar larvae were injected. Therefore, O. furnacalis larvae are induced to produce antimicrobial materials in the hemolymph after the infection, and increase of lysozyme and attacin may contribute to the antimicrobial activity.
Collapse
Affiliation(s)
- Mingming Zhang
- Department of Entomology, China Agricultural University, Beijing 100193, P. R. China
| | | | | | | | | |
Collapse
|
55
|
Identification of immune response-related genes in the Chinese oak silkworm, Antheraea pernyi by suppression subtractive hybridization. J Invertebr Pathol 2013; 114:313-23. [PMID: 24076149 DOI: 10.1016/j.jip.2013.09.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Revised: 08/26/2013] [Accepted: 09/05/2013] [Indexed: 12/21/2022]
Abstract
Insects possess an innate immune system that responds to invading microorganisms. In this study, a subtractive cDNA library was constructed to screen for immune response-related genes in the fat bodies of Antheraea pernyi (Lepidoptera: Saturniidae) pupa challenged with Escherichia coli. Four hundred putative EST clones were identified by suppression subtractive hybridization (SSH), including 50 immune response-related genes, three cytoskeleton genes, eight cell cycle and apoptosis genes, five respiration and energy metabolism genes, five transport genes, 40 metabolism genes, ten stress response genes, four transcription and translation regulation genes and 77 unknown genes. To verify the reliability of the SSH data, the transcription of a set of randomly selected immune response-related genes were confirmed by semi-quantitative reverse transcription-PCR (RT-PCR) and real-time quantitative reverse transcription-PCR (qRT-PCR). These identified immune response-related genes provide insight into understanding the innate immunity in A. pernyi.
Collapse
|
56
|
Yi HY, Deng XJ, Yang WY, Zhou CZ, Cao Y, Yu XQ. Gloverins of the silkworm Bombyx mori: structural and binding properties and activities. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2013; 43:612-25. [PMID: 23567591 PMCID: PMC3760519 DOI: 10.1016/j.ibmb.2013.03.013] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 03/21/2013] [Accepted: 03/26/2013] [Indexed: 05/12/2023]
Abstract
Gloverins are basic, glycine-rich and heat-stable antibacterial proteins (∼14- kDa) in lepidopteran insects with activity against Escherichia coli, Gram-positive bacteria, fungi and a virus. Hyalophora gloveri gloverin adopts a random coil structure in aqueous solution but has α-helical structure in membrane-like environment, and it may interact with the lipid A moiety of lipopolysaccharide (LPS). Manduca sexta gloverin binds to the O-specific antigen and outer core carbohydrate of LPS. In the silkworm Bombyx mori, there are four gloverins with slightly acidic to neutral isoelectric points. In this study, we investigate structural and binding properties and activities of B. mori gloverins (BmGlvs), as well as correlations between structure, binding property and activity. Recombinant BmGlv1-4 were expressed in bacteria and purified. Circular dichroism (CD) spectra showed that all four BmGlvs mainly adopted random coli structure (>50%) in aqueous solution in regardless of pH, but contained α-helical structure in the presence of 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP), smooth and rough mutants (Ra, Rc and Re) of LPS and lipid A. Plate ELISA assay showed that BmGlvs at pH 5.0 bound to rough mutants of LPS and lipid A but not to smooth LPS. Antibacterial activity assay showed that positively charged BmGlvs (at pH 5.0) were active against E. coli mutant strains containing rough LPS but inactive against E. coli with smooth LPS. Our results suggest that binding to rough LPS is the prerequisite for the activity of BmGlvs against E. coli.
Collapse
Affiliation(s)
- Hui-Yu Yi
- Laboratory of Insect Molecular Biology and Biotechnology, Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou 510642, China
- Division of Cell Biology and Biophysics, School of Biological Sciences, University of Missouri-Kansas City, 5007 Rockhill Road, Kansas City, MO 64110, USA
| | - Xiao-Juan Deng
- Laboratory of Insect Molecular Biology and Biotechnology, Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou 510642, China
| | - Wan-Ying Yang
- Laboratory of Insect Molecular Biology and Biotechnology, Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou 510642, China
| | - Cong-Zhao Zhou
- School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Yang Cao
- Laboratory of Insect Molecular Biology and Biotechnology, Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou 510642, China
- Corresponding author. (Y. Cao),
| | - Xiao-Qiang Yu
- Division of Cell Biology and Biophysics, School of Biological Sciences, University of Missouri-Kansas City, 5007 Rockhill Road, Kansas City, MO 64110, USA
- Corresponding author. Tel.: +1 816 235 6379; fax: +1 816 235 1503. (X.-Q. Yu)
| |
Collapse
|
57
|
Park SI, An HS, Chang BS, Yoe SM. Expression, cDNA cloning, and characterization of the antibacterial peptide cecropin D fromAgrius convolvuli. Anim Cells Syst (Seoul) 2013. [DOI: 10.1080/19768354.2013.769465] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
|
58
|
Navarro-Cerrillo G, Hernández-Martínez P, Vogel H, Ferré J, Herrero S. A new gene superfamily of pathogen-response (repat) genes in Lepidoptera: Classification and expression analysis. Comp Biochem Physiol B Biochem Mol Biol 2013; 164:10-7. [DOI: 10.1016/j.cbpb.2012.09.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Revised: 09/21/2012] [Accepted: 09/25/2012] [Indexed: 01/17/2023]
|
59
|
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.
Collapse
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
| |
Collapse
|
60
|
Pascual L, Jakubowska AK, Blanca JM, Cañizares J, Ferré J, Gloeckner G, Vogel H, Herrero S. The transcriptome of Spodoptera exigua larvae exposed to different types of microbes. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2012; 42:557-570. [PMID: 22564783 DOI: 10.1016/j.ibmb.2012.04.003] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Revised: 04/04/2012] [Accepted: 04/07/2012] [Indexed: 05/31/2023]
Abstract
We have obtained and characterized the transcriptome of Spodoptera exigua larvae with special emphasis on pathogen-induced genes. In order to obtain a highly representative transcriptome, we have pooled RNA from diverse insect colonies, conditions and tissues. Sequenced cDNA included samples from 3 geographically different colonies. Enrichment of RNA from pathogen-related genes was accomplished by exposing larvae to different pathogenic and non-pathogenic microbial agents such as the bacteria Bacillus thuringiensis, Micrococcus luteus, and Escherichia coli, the yeast Saccharomyces cerevisiae, and the S. exigua nucleopolyhedrovirus (SeMNPV). In addition, to avoid the loss of tissue-specific genes we included cDNA from the midgut, fat body, hemocytes and integument derived from pathogen exposed insects. RNA obtained from the different types of samples was pooled, normalized and sequenced. Analysis of the sequences obtained using the Roche 454 FLX and Sanger methods has allowed the generation of the largest public set of ESTs from S. exigua, including a large group of immune genes, and the identification of an important number of SSR (simple sequence repeats) and SNVs (single nucleotide variants: SNPs and INDELs) with potential use as genetic markers. Moreover, data mining has allowed the discovery of novel RNA viruses with potential influence in the insect population dynamics and the larval interactions with the microbial pesticides that are currently in use for the biological control of this pest.
Collapse
Affiliation(s)
- Laura Pascual
- Instituto de Conservación y Mejora de la Agrodiversidad Valenciana (COMAV), Universidad Politécnica de Valencia, Camino de Vera s/n, Valencia, Spain
| | | | | | | | | | | | | | | |
Collapse
|
61
|
Navarro-Cerrillo G, Ferré J, de Maagd RA, Herrero S. Functional interactions between members of the REPAT family of insect pathogen-induced proteins. INSECT MOLECULAR BIOLOGY 2012; 21:335-342. [PMID: 22404489 DOI: 10.1111/j.1365-2583.2012.01139.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Studies on the transcriptional response to pathogens in the insect larval gut have shown the regulation of several genes after the infection. Repat (REsponse to PAThogens) genes were first identified in Spodoptera exigua midgut as being up-regulated in response to the exposure to Bacillus thuringiensis toxins and baculovirus. Recently, new members of the REPAT family showed a constitutive up-regulation in a B. thuringiensis-resistant population. Based on a yeast two-hybrid screening, we have detected the interaction of REPAT1 with other members of the REPAT family, leading to the discovery of a new member: REPAT8. The functional role of this interaction was shown by following the changes of the subcellular localization of REPAT1 in the presence of REPAT8. REPAT1 alone was localized exclusively in the cytoplasm, while the presence of REPAT8 led to the migration of REPAT1 to the nucleus. Finally, analysis of the expression pattern of eight REPAT members has shown that B. thuringiensis-related treatments (Cry1Ca toxin, Xentari™ product and an acrystalliferous strain) induced a general up-regulation of repat genes, especially of repat2. In contrast, no significant effect was detected after treatment with Escherichia coli or Enterococcus sp., or by the presence of microbiota in the midgut. The results suggest that the different repat genes play different roles in response to pathogens.
Collapse
|
62
|
Duvic B, Jouan V, Essa N, Girard PA, Pagès S, Abi Khattar Z, Volkoff NA, Givaudan A, Destoumieux-Garzon D, Escoubas JM. Cecropins as a marker of Spodoptera frugiperda immunosuppression during entomopathogenic bacterial challenge. JOURNAL OF INSECT PHYSIOLOGY 2012; 58:881-888. [PMID: 22487443 DOI: 10.1016/j.jinsphys.2012.04.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Revised: 03/30/2012] [Accepted: 04/02/2012] [Indexed: 05/31/2023]
Abstract
An antimicrobial peptide (AMP) of the cecropin family was isolated by HPLC from plasma of the insect pest, Spodoptera frugiperda. Its molecular mass is 3910.9 Da as determined by mass spectrometry. Thanks to the EST database Spodobase, we were able to describe 13 cDNAs encoding six different cecropins which belong to the sub-families CecA, CecB, CecC and CecD. The purified peptide identified as CecB1 was chemically synthesized (syCecB1). It was shown to be active against Gram-positive and Gram-negative bacteria as well as fungi. Two closely related entomopathogenic bacteria, Xenorhabdus nematophila F1 and Xenorhabdus mauleonii VC01(T) showed different susceptibility to syCecB1. Indeed, X. nematophila was sensitive to syCecB1 whereas X. mauleonii had a minimal inhibitory concentration (MIC) eight times higher. Interestingly, injection of live X. nematophila into insects did not induce the expression of AMPs in hemolymph. This effect was not observed when this bacterium was heat-killed before injection. On the opposite, both live and heat-killed X. mauleonii induced the expression of AMPs in the hemolymph of S. frugiperda. The same phenomenon was observed for another immune-related protein lacking antimicrobial activity. Altogether, our data suggest that Xenorhabdus strains have developed different strategies to supplant the humoral defense mechanisms of S. frugiperda, either by increasing their resistance to AMPs or by preventing their expression during such host-pathogen interaction.
Collapse
Affiliation(s)
- B Duvic
- INRA, UMR1333, Laboratoire Diversité, Génomes et Interactions Microorganismes Insectes, Montpellier, France.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
63
|
Zhao C, Zhang T, Zhang X, Hu S, Xiang J. Sequencing and analysis of four BAC clones containing innate immune genes from the Zhikong scallop (Chlamys farreri). Gene 2012; 502:9-15. [PMID: 22542508 DOI: 10.1016/j.gene.2012.04.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Revised: 02/29/2012] [Accepted: 04/05/2012] [Indexed: 11/17/2022]
Abstract
The sequencing of BAC clones (~100 kb) can reveal some characteristics of a genome that are challenging to obtain based on short sequences. Additionally, although the immune genes of the Zhikong scallop (Chlamys farreri) have been studied widely, few analyses have been conducted at the DNA level. In this study, four C. farreri BAC clones containing innate immune genes, including hsp70, l gbp (lipopolysaccharide and beta-1,3-glucan binding protein), serine protease and a gene with an immunoglobulin-like domain, were sequenced and analyzed both to explore the genomic characteristics of C. farreri based on long DNA sequences and to promote the study of C. farreri immune genes at the DNA level. The total length of the four BACs was 389.98 kb. A total of 34 genes were predicted in these sequences, and several features of protein-coding regions in the C. farreri genome were inferred based on this information. Two LGBP genes were located close together in a 22-kb region in one BAC clone, indicating the physical linkage of some immune genes in C. farreri. A cluster of membrane transport genes was also observed; these genes might play important roles in eliminating toxins in C. farreri, which lives as a filter feeder. Further analysis showed 15.43% of the BAC sequence was repetitive. Tandem repeats were the most abundant repeat type, followed by transposable elements. A total of 31 SSRs were predicted in the four BACs. An IS10 family transposon was identified, and a suspected regulatory non-coding RNA gene for this transposon (RNA-OUT) was observed to overlap with it complementarily. This work will promote future studies on the genomics, immune system and non-coding regions of C. farreri.
Collapse
Affiliation(s)
- Cui Zhao
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, Shandong, China
| | | | | | | | | |
Collapse
|
64
|
Chieda Y, Iiyama K, Lee JM, Kusakabe T, Yasunaga-Aoki C, Shimizu S. Virulence of an exotoxin A-deficient strain of Pseudomonas aeruginosa toward the silkworm, Bombyx mori. Microb Pathog 2011; 51:407-14. [PMID: 21945328 DOI: 10.1016/j.micpath.2011.09.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2010] [Revised: 08/31/2011] [Accepted: 09/06/2011] [Indexed: 01/01/2023]
Abstract
We studied the contribution of exotoxin A to the virulence of Pseudomonas aeruginosa against the silkworm, Bombyx mori. First, an exotoxin A-deficient mutant strain (PAO1toxA) was created, and its virulence compared with that of the parental PAO1 strain. In a short-term mortality assay, the mutant harboring pBBR1MCS2 did not kill B. mori until 120 h after inoculation and complementation of the corresponding gene in trans restored the strain's virulence. Next, to ascertain whether or not it lost all virulence, PAO1toxA (pBBR1MCS2, pGFP) was used in a long-term mortality assay. B. mori inoculated with the mutant strain did not die until early in the 5th instar (240 h after inoculation). However, 50% of the inoculated B. mori died late in the 5th instar or in the early pupal stage (408 h after inoculation). All had died by the pupal stage (600 h after inoculation). The mutant strain was isolated from dead larvae and cocoons. The bacterial population of PAO1toxA in hemolymph reached 4.77 × 10(7) cfu/ml. These results indicated that exotoxin A acts as a virulence factor in B. mori and that other virulence factor(s) are involved during the late stages of infection.
Collapse
Affiliation(s)
- Yuuka Chieda
- Laboratory of Insect Pathology and Microbial Control, Institute of Biological Control, Graduate School, Kyushu University, Hakozaki 6-10-1, Higashi-ku, Fukuoka 812-8581, Japan
| | | | | | | | | | | |
Collapse
|
65
|
Rao XJ, Xu XX, Yu XQ. Manduca sexta moricin promoter elements can increase promoter activities of Drosophila melanogaster antimicrobial peptide genes. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2011; 41:982-92. [PMID: 22005212 PMCID: PMC3210862 DOI: 10.1016/j.ibmb.2011.09.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Revised: 09/19/2011] [Accepted: 09/30/2011] [Indexed: 05/13/2023]
Abstract
Insects produce a variety of antimicrobial peptides (AMPs). Induction of insect AMP genes is regulated by the Toll and IMD (immune deficiency) pathways via NF-κB and GATA factors. Little is known about species-specific regulation of AMP genes. In this report, we showed that activities of most Manduca sexta and Drosophila melanogaster AMP gene promoters were regulated in a species-specific manner in Drosophila (Dipteran) S2 cells and Spodoptera frugiperda (Lepidopteran) Sf9 cells. A κB-GATA element (22 bp) from M. sexta moricin (MsMoricin) promoter could significantly increase activities of Drosophila AMP gene promoters in S2 cells, and an MsMoricin promoter activating element (MPAE) (140 bp) could increase activity of drosomycin promoter specifically in Sf9 cells. However, κB and GATA factors alone were not sufficient for MsMoricin gene activation, suggesting that other co-regulators may be required to fully activate AMP genes. Our results suggest that induction of insect AMP genes may require a transcription complex composed of common nuclear factors (such as NF-κB and GATA factors) and species-related co-regulators, and it is the co-regulators that may confer species-specific regulation of AMP genes. In addition, we showed that activity of Drosophila drosomycin promoter could be activated cooperatively by the inserted exogenous κB-GATA element and the endogenous κB element. These findings revealed an approach of engineering AMP genes with enhanced activities, which may lead to broad applications.
Collapse
Affiliation(s)
| | | | - Xiao-Qiang Yu
- Send correspondence to: Xiao-Qiang Yu, PhD, Division of Cell Biology and Biophysics, School of Biological Sciences, University of Missouri-Kansas City, 5007 Rockhill Road, Kansas City, MO 64110, Telephone: (816)-235-6379, Fax: (816)-235-1503,
| |
Collapse
|
66
|
Seufi AM, Hafez EE, Galal FH. Identification, phylogenetic analysis and expression profile of an anionic insect defensin gene, with antibacterial activity, from bacterial-challenged cotton leafworm, Spodoptera littoralis. BMC Mol Biol 2011; 12:47. [PMID: 22067477 PMCID: PMC3234185 DOI: 10.1186/1471-2199-12-47] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Accepted: 11/09/2011] [Indexed: 11/15/2022] Open
Abstract
Background Defensins are a well known family of cationic antibacterial peptides (AMPs) isolated from fungi, plants, insects, mussels, birds, and various mammals. They are predominantly active against gram (+) bacteria, and a few of them are also active against gram (-) bacteria and fungi. All insect defensins belonging to the invertebrate class have a consensus motif, C-X5-16-C-X3-C-X9-10-C-X4-7-CX1-C. Only seven AMPs have already been found in different lepidopteran species. No report was published on the isolation of defensin from the Egyptian cotton leafworm, Spodoptera littoralis. Results An anionic defensin, termed SpliDef, was isolated from the haemolymph of the cotton leafworm, S. littoralis, after bacterial challenge using differential display technique. Based on sequence analyses of the data, specific primers for full length and mature peptide of defensin were designed and successfully amplified 471 and 150 bp amplicons. The integration of the results revealed that the 471 bp-PCR product has one open reading frame (orf) of 303 bp long, including both start codon (AUG) and stop codon (UGA). The deduced peptide consists of a 23-residues signal peptide, a 27-residues propeptide and a 50-residues mature peptide with the conserved six-cysteine motif of insect defensins. Both haemolymph and expressed protein exhibited antibacterial activities comparable to positive control. The RT-qPCR indicated that it was more than 41-folds up-regulated at 48 h p.i. Conclusion Our results highlight an important immune role of the defensin gene in Spodoptera littoralis by cooperating with other AMPs to control bacterial infection.
Collapse
Affiliation(s)
- Alaaeddeen M Seufi
- Department of Entomology, Faculty of Science, Cairo university, 9 Gamaa St. Giza, 12613, Egypt.
| | | | | |
Collapse
|
67
|
Hwang J, Kim Y. RNA interference of an antimicrobial peptide, gloverin, of the beet armyworm, Spodoptera exigua, enhances susceptibility to Bacillus thuringiensis. J Invertebr Pathol 2011; 108:194-200. [DOI: 10.1016/j.jip.2011.09.003] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Revised: 08/31/2011] [Accepted: 09/02/2011] [Indexed: 11/24/2022]
|
68
|
Vogel H, Altincicek B, Glöckner G, Vilcinskas A. A comprehensive transcriptome and immune-gene repertoire of the lepidopteran model host Galleria mellonella. BMC Genomics 2011; 12:308. [PMID: 21663692 PMCID: PMC3224240 DOI: 10.1186/1471-2164-12-308] [Citation(s) in RCA: 181] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Accepted: 06/11/2011] [Indexed: 01/20/2023] Open
Abstract
Background The larvae of the greater wax moth Galleria mellonella are increasingly used (i) as mini-hosts to study pathogenesis and virulence factors of prominent bacterial and fungal human pathogens, (ii) as a whole-animal high throughput infection system for testing pathogen mutant libraries, and (iii) as a reliable host model to evaluate the efficacy of antibiotics against human pathogens. In order to compensate for the lack of genomic information in Galleria, we subjected the transcriptome of different developmental stages and immune-challenged larvae to next generation sequencing. Results We performed a Galleria transcriptome characterization on the Roche 454-FLX platform combined with traditional Sanger sequencing to obtain a comprehensive transcriptome. To maximize sequence diversity, we pooled RNA extracted from different developmental stages, larval tissues including hemocytes, and from immune-challenged larvae and normalized the cDNA pool. We generated a total of 789,105 pyrosequencing and 12,032 high-quality Sanger EST sequences which clustered into 18,690 contigs with an average length of 1,132 bases. Approximately 40% of the ESTs were significantly similar (E ≤ e-03) to proteins of other insects, of which 45% have a reported function. We identified a large number of genes encoding proteins with established functions in immunity related sensing of microbial signatures and signaling, as well as effector molecules such as antimicrobial peptides and inhibitors of microbial proteinases. In addition, we found genes known as mediators of melanization or contributing to stress responses. Using the transcriptomic data, we identified hemolymph peptides and proteins induced upon immune challenge by 2D-gelelectrophoresis combined with mass spectrometric analysis. Conclusion Here, we have developed extensive transcriptomic resources for Galleria. The data obtained is rich in gene transcripts related to immunity, expanding remarkably our knowledge about immune and stress-inducible genes in Galleria and providing the complete sequences of genes whose primary structure have only partially been characterized using proteomic methods. The generated data provide for the first time access to the genetic architecture of immunity in this model host, allowing us to elucidate the molecular mechanisms underlying pathogen and parasite response and detailed analyses of both its immune responses against human pathogens, and its coevolution with entomopathogens.
Collapse
Affiliation(s)
- Heiko Vogel
- Institute of Phytopathology and Applied Zoology, University of Giessen, Heinrich-Buff-Ring 26-32, 35392 Giessen, Germany
| | | | | | | |
Collapse
|
69
|
Yang W, Cheng T, Ye M, Deng X, Yi H, Huang Y, Tan X, Han D, Wang B, Xiang Z, Cao Y, Xia Q. Functional divergence among silkworm antimicrobial peptide paralogs by the activities of recombinant proteins and the induced expression profiles. PLoS One 2011; 6:e18109. [PMID: 21479226 PMCID: PMC3066212 DOI: 10.1371/journal.pone.0018109] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Accepted: 02/25/2011] [Indexed: 11/21/2022] Open
Abstract
Antimicrobial peptides are small-molecule proteins that are usually encoded by multiple-gene families. They play crucial roles in the innate immune response, but reports on the functional divergence of antimicrobial peptide gene families are rare. In this study, 14 paralogs of antimicrobial peptides belonging to cecropin, moricin and gloverin families were recombinantly expressed in pET expression systems. By antimicrobial activity tests, peptides representing paralogs in the same family of cecropin and moricin families, displayed remarkable differences against 10 tested bacteria. The evolutionary rates were relatively fast in the two families, which presented obvious functional divergence among paralogs of each family. Four peptides of gloverin family had similar antimicrobial spectrum and activity against tested bacteria. The gloverin family showed similar antimicrobial function and slow evolutionary rates. By induced transcriptional activity, genes encoding active antimicrobial peptides were upregulated at obviously different levels when silkworm pupae were infected by three types of microbes. Association analysis of antimicrobial activities and induced transcriptional activities indicated that the antimicrobial activities might be positively correlated with induced transcriptional activities in the cecropin and moricin families. These results suggest that representative BmcecB6, BmcecD and Bmmor as the major effector genes have broad antimicrobial spectrum, strong antimicrobial activity and high microbe-induced expression among each family and maybe play crucial roles in eliminating microbial infection.
Collapse
Affiliation(s)
- Wanying Yang
- Laboratory of Insect Molecular Biology and Biotechnology, Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Tingcai Cheng
- Institute of Agriculture and Life Science, Chongqing University, Chongqing, China
| | - Mingqiang Ye
- Laboratory of Insect Molecular Biology and Biotechnology, Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, China
- The Sericulture & Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Xiaojuan Deng
- Laboratory of Insect Molecular Biology and Biotechnology, Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Huiyu Yi
- Laboratory of Insect Molecular Biology and Biotechnology, Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Yadong Huang
- Biopharmaceutical Research and Development Center, Jinan University, Guangzhou, China
| | - Xiang Tan
- Institute of Sericulture and Systems Biology, Southwest University, Chongqing, China
| | - Dong Han
- Laboratory of Insect Molecular Biology and Biotechnology, Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Bo Wang
- Institute of Sericulture and Systems Biology, Southwest University, Chongqing, China
| | - Zhonghuai Xiang
- Institute of Sericulture and Systems Biology, Southwest University, Chongqing, China
| | - Yang Cao
- Laboratory of Insect Molecular Biology and Biotechnology, Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, China
- * E-mail: (YC); (QX)
| | - Qingyou Xia
- Institute of Agriculture and Life Science, Chongqing University, Chongqing, China
- Institute of Sericulture and Systems Biology, Southwest University, Chongqing, China
- * E-mail: (YC); (QX)
| |
Collapse
|
70
|
Hernández-Martínez P, Naseri B, Navarro-Cerrillo G, Escriche B, Ferré J, Herrero S. Increase in midgut microbiota load induces an apparent immune priming and increases tolerance to Bacillus thuringiensis. Environ Microbiol 2011; 12:2730-7. [PMID: 20482744 DOI: 10.1111/j.1462-2920.2010.02241.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The insect immune system is comprised of both humoral and cellular components that are mobilized in response to parasitic or pathogenic infections. Activation of the immune response implies a considerable expenditure of energy and that is why insects rely on inducible pathways that are activated after coming into contact with the pathogenic agent. Known as immune priming, insects can prolong the activation of the immune response and transmit their immune status to the next generation. Starting from a laboratory colony of the lepidopteran Spodoptera exigua and using the lytic zone assay as a measure of the immune status, we selected for a sub-colony with high levels of immune activity in the absence of external challenging with bacteria. Immune-activated insect showed characteristics that are typical reported for immune primed insects, such as increased tolerance to pathogens (Bacillus thuringiensis in our case), fitness-cost associated to the immune status, and maternal transmission of the immune status. However, additional analysis revealed that the selection for the immune-activated insects was based on the selection of insects carrying a higher bacterial load in the midgut. Our results suggest that activation of the immune system in S. exigua may not only occur as consequence of the immune priming but also from an increase in midgut microbiota load.
Collapse
|
71
|
Rao XJ, Yu XQ. Lipoteichoic acid and lipopolysaccharide can activate antimicrobial peptide expression in the tobacco hornworm Manduca sexta. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2010; 34:1119-28. [PMID: 20600279 PMCID: PMC2914183 DOI: 10.1016/j.dci.2010.06.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2010] [Revised: 06/09/2010] [Accepted: 06/09/2010] [Indexed: 05/03/2023]
Abstract
Activation of prophenoloxidase and synthesis of antimicrobial peptides (AMPs) are two important innate immune mechanisms in insects. In the current study, we investigated immune responses activated by three major bacterial components, lipopolysaccharide (LPS) (including rough mutants of LPS), lipoteichoic acid (LTA), and peptidoglycan (PG), in the larvae of a lepidopteran insect, Manduca sexta. We found that two DAP (diaminopimelic acid)-type PGs from Escherichia coli and Bacillus subtilis were much more potent than LPS and LTA from the respective bacteria as well as a Lysine-type PG in activation of prophenoloxidase in M. sexta larval plasma in vitro. Transcription levels of AMP genes, such as Attacin, Lebocin and Moricin genes, in the hemocytes and fat body of larvae were significantly induced by smooth LPS (TLR4grade) and rough mutants of LPS (TLRgrade), synthetic lipid A, LTA, and PG. LPS from E. coli and LTA from B. subtilis activated AMP expression to significantly higher levels than PGs from the respective bacterial strains, and smooth LPS were more potent than lipid A and rough mutants of LPS in activation of AMP expression. Our results demonstrated for the first time that LTA can activate AMP expression, and different moieties of LPS may synergistically activate AMP expression in M. sexta.
Collapse
Affiliation(s)
| | - Xiao-Qiang Yu
- Send correspondence to: Xiao-Qiang Yu, Ph.D., Division of Cell Biology and Biophysics, School of Biological Sciences, University of Missouri-Kansas City, 5007 Rockhill Road, Kansas City, MO 64110, Telephone: (816)-235-6379, Fax: (816)-235-1503,
| |
Collapse
|
72
|
Ponnuvel KM, Subhasri N, Sirigineedi S, Murthy GN, Vijayaprakash NB. Molecular evolution of the cecropin multigene family in silkworm Bombyx mori. Bioinformation 2010; 5:97-103. [PMID: 21364788 PMCID: PMC3040484 DOI: 10.6026/97320630005097] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Accepted: 08/26/2010] [Indexed: 11/23/2022] Open
Abstract
Cecropins constitute one of the largest and most potent immune protein families found in insect species with diversified numbers and features. In view of the large number of cecropin proteins existing with much sequence variations among them, an overview of the multigene cecropin family in silkworm Bombyx mori was attempted in this study. Cecropin encodes an inducible 64 residue anti-bacterial peptide and was clustered into two groups; first group viz. A and second group including B, D, E and Enbocin. Cecropin A consisted of two sub-groups located on chromosome number 6 of B.mori genome. Cecropin B consisted of six sub-groups, cecropin D and E of one each and Enbocin of two. The second sub-group formed in tandem array of multigene family locus over a length of 78.62 kb on chromosome number 26 in B.mori genome and was organized in positive as well as opposite orientation. The results indicated that cecropin B genes were organized in a close cluster with the intergenic sequence ranging from 1366 bp to 23526 bp. Interestingly a distantly related cecropin E was also located within the cecropin B multigene locus. Similarly distant members like cecropin D and Enbocin were also located in the 3' region of cecropin B locus. The maximum intergenic region of 23526 bp observed between Cecropin D and Enbocin indicates that the two genes were distantly evolved. The phylogenetic analysis clearly indicates a positive correlation between the clusters and physical location on the chromosome, as the length of the intergenic region plays a major role to create newer cecropin families. EST database analysis suggests that most of the cecropin A members were expressed in the microbial fat body while, the cecropin B was equally expressed in fat body and other target tissues. The signal peptides were conserved in all the twelve paralogous gene sequences.
Collapse
Affiliation(s)
- Kangayam M Ponnuvel
- Seribiotech Research Laboratory, Carmelaram‐ Post, Sarjapura Road, Kodathi, Bangalore‐ 560 035, INDIA
| | - Natarajan Subhasri
- Seribiotech Research Laboratory, Carmelaram‐ Post, Sarjapura Road, Kodathi, Bangalore‐ 560 035, INDIA
| | - Sasibhushan Sirigineedi
- Seribiotech Research Laboratory, Carmelaram‐ Post, Sarjapura Road, Kodathi, Bangalore‐ 560 035, INDIA
| | - Geetha N Murthy
- Seribiotech Research Laboratory, Carmelaram‐ Post, Sarjapura Road, Kodathi, Bangalore‐ 560 035, INDIA
| | - Nanjappa B Vijayaprakash
- Seribiotech Research Laboratory, Carmelaram‐ Post, Sarjapura Road, Kodathi, Bangalore‐ 560 035, INDIA
| |
Collapse
|
73
|
Rayaprolu S, Wang Y, Kanost MR, Hartson S, Jiang H. Functional analysis of four processing products from multiple precursors encoded by a lebocin-related gene from Manduca sexta. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2010; 34:638-47. [PMID: 20096726 PMCID: PMC2841005 DOI: 10.1016/j.dci.2010.01.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2009] [Revised: 01/07/2010] [Accepted: 01/12/2010] [Indexed: 05/10/2023]
Abstract
Antimicrobial peptides (AMPs) are a crucial component of the natural immune system in insects. Five types of AMPs have been identified in the tobacco hornworm Manduca sexta, including attacin, cecropin, moricin, gloverin, and lebocin. Here we report the isolation of lebocin-related cDNA clones and antibacterial activity of their processed protein products. The 17 cDNA sequences are composed of a constant 5' end and a variable 3' region containing 3-16 copies of an 81-nucleotide repeat. The sequence of the corresponding gene isolated from a M. sexta genomic library and Southern blotting results indicated that the gene lacks introns and exists as a single copy in the genome. The genomic sequence contained 13 complete and one partial copy of the 81-nucleotide repeat. Northern blot analysis revealed multiple transcripts with major size differences. The mRNA level of M. sexta lebocin increased substantially in fat body after larvae had been injected with bacteria. The RXXR motifs in the protein sequences led us to postulate that the precursors are processed by an intracellular convertase to form four bioactive peptides. To test this hypothesis, we chemically synthesized the peptides and examined their antibacterial activity. Peptide 1 killed Gram-positive and Gram-negative bacteria. Peptide 2, similar in sequence to a Galleria mellonella AMP, did not affect the bacterial growth. Peptide 3 was inactive but peptide 3 with an extra Arg at the carboxyl terminus was active against Escherichia coli at a high minimum inhibitory concentration. Peptide 4, encoded by the 81-bp repeat, was inactive in the antibacterial tests. The hypothesis that posttranslational processing of the precursor proteins produces multiple bioactive peptides for defense purposes was validated by identification of peptides 1, 2, and 3 from larval hemolymph via liquid chromatography and tandem mass spectrometry. Comparison with the orthologs from other lepidopteran insects indicates that the same mechanism may be used to generate several functional products from a single precursor.
Collapse
Affiliation(s)
- Subrahmanyam Rayaprolu
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Yang Wang
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Michael R. Kanost
- Department of Biochemistry, Kansas State University, Manhattan, KS 66506, USA
| | - Steven 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
| |
Collapse
|
74
|
Shen X, Ye G, Cheng X, Yu C, Altosaar I, Hu C. Characterization of an abaecin-like antimicrobial peptide identified from a Pteromalus puparum cDNA clone. J Invertebr Pathol 2010; 105:24-9. [PMID: 20466006 DOI: 10.1016/j.jip.2010.05.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2009] [Revised: 04/16/2010] [Accepted: 05/07/2010] [Indexed: 11/29/2022]
Abstract
Abaecin is a major antimicrobial peptide, initially identified from the honeybee. In our effort to discover new antimicrobial peptides from the endoparasitoid wasp Pteromalus puparum, we identified an antibacterial cDNA clone that codes a fragment with high amino acid sequence similarity to abaecin. The proline-rich peptide (YVPPVQKPHPNGPKFPTFP, named PP30) was chemically synthesized and characterized in this study. Antimicrobial assays indicated that the cationic peptide was active against both Gram-negative and positive bacteria, but not active against fungi tested. No hemolytic activity was observed against human erythrocytes after 1h incubation at concentration of 125 microM or below. The antibacterial activity of PP30 against Escherichia coli was attenuated in the presence of increasing concentrations of NaCl. Transmission electron microscopic (TEM) examination of PP30-treated E. coli cells showed morphological changes in the cells and extensive damage to the cell membranes. The circular dichroism (CD) spectroscopy studies indicated that PP30 formed random coil structures in phosphate buffer (pH 7.4), 50% TFE and 25 mM SDS solution. Expression analysis of the gene coding for the peptide indicated that its expression was upregulated upon bacterial infection, indicating that the gene may play a role in preventing potential infection by microorganisms during parasitization in Pieris rapae.
Collapse
Affiliation(s)
- Xiaojing Shen
- State Key Laboratory of Rice Biology, Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | | | | | | | | | | |
Collapse
|
75
|
Brown SE, Howard A, Kasprzak AB, Gordon KH, East PD. A peptidomics study reveals the impressive antimicrobial peptide arsenal of the wax moth Galleria mellonella. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2009; 39:792-800. [PMID: 19786100 DOI: 10.1016/j.ibmb.2009.09.004] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2009] [Revised: 09/07/2009] [Accepted: 09/21/2009] [Indexed: 05/28/2023]
Abstract
The complete antimicrobial peptide repertoire of Galleria mellonella was investigated for the first time by LC/MS. Combining data from separate trypsin, Glu-C and Asp-N digests of immune hemolymph allowed detection of 18 known or putative G. mellonella antimicrobial peptides or proteins, namely lysozyme, moricin-like peptides (5), cecropins (2), gloverin, Gm proline-rich peptide 1, Gm proline-rich peptide 2, Gm anionic peptide 1 (P1-like), Gm anionic peptide 2, galiomicin, gallerimycin, inducible serine protease inhibitor 2, 6tox and heliocin-like peptide. Six of these were previously known only as nucleotide sequences, so this study provides the first evidence for expression of these genes. LC/MS data also provided insight into the expression and processing of the antimicrobial Gm proline-rich peptide 1. The gene for this peptide was isolated and shown to be unique to moths and to have an unusually long precursor region (495 bp). The precursor region contained other proline-rich peptides and LC/MS data suggested that these were being specifically processed and were present in hemolymph at very high levels. This study shows that G. mellonella can concurrently release an impressive array of at least 18 known or putative antimicrobial peptides from 10 families to defend itself against invading microbes.
Collapse
|
76
|
Liu F, Ling E, Wu S. Gene expression profiling during early response to injury and microbial challenges in the silkworm, Bombyx mori. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2009; 72:16-33. [PMID: 19557735 DOI: 10.1002/arch.20320] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
To identify Bombyx mori genes involved in the early response to injury and microbial challenge, we performed genome-wide gene expression-profiling experiments using oligonucleotide DNA microarrays. Of approximately 23,000 genes examined, 465 displayed changes in mRNA expression levels. Of these, 306 were induced and 159 were repressed in response to injury (injection with phosphate buffer saline) or challenges by Gram-negative (Serratia marcescens), Gram-positive bacteria (Staphylococcus aureus), or fungus (Beauveria bassiana). Many of these differentially expressed genes can be assigned to specific functional groups of the innate immune response, including recognition, signaling, melanization and coagulation, and antimicrobial peptides. Seventeen percent of differentially expressed genes encode proteins with no obvious similarity to known functional domains. Of particular interest is a member of the juvenile hormone-binding protein family, which was highly induced by both injury and microbial challenges. The possible role of juvenile hormone in innate immunity is discussed.
Collapse
Affiliation(s)
- Fei Liu
- Research Center for Insect Science, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences Graduate School, Shanghai, People's Republic of China
| | | | | |
Collapse
|
77
|
Hernández-Rodríguez CS, Ferré J, Herrero S. Genomic structure and promoter analysis of pathogen-induced repat genes from Spodoptera exigua. INSECT MOLECULAR BIOLOGY 2009; 18:77-85. [PMID: 19076251 DOI: 10.1111/j.1365-2583.2008.00850.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The repat gene family encodes midgut proteins overexpressed in response to pathogen infection in the lepidopteran Spodoptera exigua. Up-regulation of repat genes has been observed after challenging the larvae with both Bacillus thuringiensis toxins and after infection with the baculovirus Autographa californica multiple nucleopolyhedrovirus. In our study, PCR amplification of the genomic region and genome walking were used to obtain the genomic structure and the sequence of the 5'-upstream region of repat1 and repat2, two of the most phylogenetically distant members of the repat family. A similar gene structure between repat1 and repat2 has been found, with conserved exon-intron positions and junction sequences, suggesting a common origin for these genes. Recombinant baculoviruses carrying the firefly luciferase gene under the control of different 5'-upstream regions of the repat1 gene were constructed to elucidate the influence of these regions in gene expression. Infection of Helicoverpa zea gut-derived cells with the recombinant baculoviruses revealed the upstream regions of the repat1 gene which are involved in gene transcription and demonstrated the role of an intron located in the 5'-untranslated region in the enhancement of gene expression.
Collapse
|
78
|
Dai H, Rayaprolu S, Gong Y, Huang R, Prakash O, Jiang H. Solution structure, antibacterial activity, and expression profile of Manduca sexta moricin. J Pept Sci 2008; 14:855-63. [PMID: 18265434 DOI: 10.1002/psc.1016] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
In response to wounding or infection, insects produce a battery of antimicrobial peptides (AMPs) and other defense molecules to kill the invading pathogens. To study their structures, functions, and transcriptional regulation, we synthesized Manduca sexta moricin, a 42-residue peptide (GKIPVKAIKQAGKVIGKGLRAINIAGTTHDVVSFFRPKKKKH, 4539 Da). The compound exhibited potent antimicrobial activities against a broad spectrum of Gram-positive and Gram-negative bacteria with a minimum inhibitory concentration of 1.4 microM. The mRNA levels of M. sexta moricin increased substantially in fat body and hemocytes after the larvae were challenged with bacterial cells. We determined the solution structure of this AMP by two-dimensional 1H-1H -nuclear magnetic resonance spectroscopy. The tertiary structure is composed of an eight-turn alpha-helix spanning almost the entire peptide. Insights of relationships between the structure and function are also presented.
Collapse
Affiliation(s)
- Huaien Dai
- Department of Biochemistry, Kansas State University, USA
| | | | | | | | | | | |
Collapse
|
79
|
Ahmed A, Al-Olayan E, Amoudy M. Enhancing the Humoral and Melanization Responses of Aedes aegypti Mosquito: A Step Towards the Utilization of Immune System Against Dengue Fever. ACTA ACUST UNITED AC 2008. [DOI: 10.3923/je.2008.305.321] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
80
|
Wang J, Hu C, Wu Y, Stuart A, Amemiya C, Berriman M, Toyoda A, Hattori M, Aksoy S. Characterization of the antimicrobial peptide attacin loci from Glossina morsitans. INSECT MOLECULAR BIOLOGY 2008; 17:293-302. [PMID: 18477243 PMCID: PMC2656931 DOI: 10.1111/j.1365-2583.2008.00805.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The antimicrobial peptide Attacin is an immune effector molecule that can inhibit the growth of gram-negative bacteria. In Glossina morsitans morsitans, which serves as the sole vectors of African trypanosomes, Attacins also play a role in trypanosome resistance, and in maintaining parasite numbers at homeostatic levels in infected individuals. We characterized the attacin encoding loci from a Bacterial Artificial Chromosome (BAC) library. The attacin genes are organized into three clusters. Cluster 1 contains two attacin (attA) genes located in head-to-head orientation, cluster 2 contains two closely related genes (attA and attB) located in a similar transcriptional orientation, and cluster 3 contains a single attacin gene (attD). Coding and transcription regulatory sequences of attA and attB are nearly identical, but differ significantly from attD. Putative AttA and AttB have signal peptide sequences, but lack the pro domain typically present in insect Attacins. Putative AttD lacks both domains. Analysis of attacin cDNA sequences shows polymorphisms that could arise either from allelic variations or from the presence of additional attacin genomic loci. Real time-PCR analysis reveals that attA and attB expression is induced in the fat body of flies per os challenged with Escherichia coli and parasitized with trypanosomes. In the midgut, expression of these attacins is similarly induced following microbial challenge, but reduced in response to parasite infections. Transcription of AttD is significantly less relative to the other two genes, and is preferentially induced in the fat body of parasitized flies. These results indicate that the different attacin genes may be differentially regulated.
Collapse
Affiliation(s)
- J Wang
- Yale University School of Medicine, Department of Epidemiology and Public Health, 60 College Street, New Haven, CT 06510, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
81
|
Wen H, Lan X, Cheng T, He N, Shiomi K, Kajiura Z, Zhou Z, Xia Q, Xiang Z, Nakagaki M. Sequence structure and expression pattern of a novel anionic defensin-like gene from silkworm (Bombyx mori). Mol Biol Rep 2008; 36:711-6. [PMID: 18360778 DOI: 10.1007/s11033-008-9233-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2007] [Accepted: 03/10/2008] [Indexed: 11/26/2022]
Abstract
A defensin-like gene, BmdefA, was rediscovered in the silkworm genome and expressed sequence tags databases. The open reading frame of BmdefA encodes a prepropeptide consisting of a 22-residue signal peptide, a 34-residue propeptide, and a 36-residue mature peptide with a molecular mass of 4.0 kDa. The mature peptide possesses the characteristic six-cysteine motif of insect defensins, and its predicted isoelectric point is 4.12, indicating it is a novel anionic defensin. An intron is present in BmdefA and several cis-regulatory elements are in the regulating region. It is transcribed constitutively at a high level in the hemocyte, silk gland, head, and ovary of the silkworm larvae, and in the fat body of early-stage pupae and moth. BmdefA is also strongly induced by immune challenge. These results suggest that BmdefA plays an important role in both immunity and metamorphosis.
Collapse
Affiliation(s)
- Hongxiu Wen
- Department of Applied Biology, Faculty of Textile Science and Technology, Shinshu University, Ueda, Nagano 386-8567, Japan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
82
|
Brown SE, Howard A, Kasprzak AB, Gordon KH, East PD. The discovery and analysis of a diverged family of novel antifungal moricin-like peptides in the wax moth Galleria mellonella. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2008; 38:201-212. [PMID: 18207081 DOI: 10.1016/j.ibmb.2007.10.009] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2007] [Revised: 10/18/2007] [Accepted: 10/30/2007] [Indexed: 05/25/2023]
Abstract
Screening for components with antifungal activity in the hemolymph of immune-stimulated Galleria mellonella larvae led to the identification of four novel moricin-like peptides (A, B, C3 and D). Subsequently, eight moricin-like peptide genes (A, B, C1-5 and D) were isolated and shown to code for seven unique peptides (mature C4 and C5 are identical). These genes contained single introns which varied from 180 to 1090bp. The moricin-like peptides were particularly active against filamentous fungi, preventing the growth of Fusarium graminearum at 3 microg/ml, and were also active against yeasts, gram positive bacteria and gram negative bacteria. Searches of the databases identified 30 moricin-like peptide genes which code for 23 unique mature peptides, all belonging to the Lepidoptera (moths and butterflies). The first comprehensive phylogenetic analysis of the moricin-like peptides suggested that they fall into two basic classes which diverged a long time ago. The peptides have since diversified extensively through a high level of gene duplication within species, as seen in G. mellonella and Bombyx mori. The restriction of moricin-like peptides to the Lepidoptera combined with their potent antifungal activity suggests that this diverse peptide family may play a role in the defence response of moths and butterflies.
Collapse
Affiliation(s)
- Susan E Brown
- CSIRO Entomology, GPO Box 1700, Acton, ACT 2601, Australia.
| | | | | | | | | |
Collapse
|
83
|
Kawaoka S, Katsuma S, Daimon T, Isono R, Omuro N, Mita K, Shimada T. Functional analysis of four Gloverin-like genes in the silkworm, Bombyx mori. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2008; 67:87-96. [PMID: 18076111 DOI: 10.1002/arch.20223] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
To identify genes involved in the innate immunity of the silkworm Bombyx mori, we constructed a cDNA library from the fat body of Escherichia coli-challenged B. mori larvae. Based on the expressed sequence tag (EST) data and whole genome shotgun sequence analysis, we found four Gloverin-like genes, BmGlov1-4, in the Bombyx genome. Northern blot and RT-PCR analysis showed that BmGlov1-4 were induced in the larval fat body after an immune challenge by the injection of E. coli; however, less induction was observed after the injection of a yeast Candida albicans. In silico sequence analysis revealed the presence of a motif homologous to NF-kappaB binding site in the upstream region of each BmGlov gene. Moreover, we expressed recombinant BmGlov1-4 proteins using the baculovirus expression system, and found that all the recombinant BmGlov1-4 significantly inhibited the growth of E. coli.
Collapse
Affiliation(s)
- Shinpei Kawaoka
- Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo, Japan
| | | | | | | | | | | | | |
Collapse
|
84
|
Cheng TC, Zhang YL, Liu C, Xu PZ, Gao ZH, Xia QY, Xiang ZH. Identification and analysis of Toll-related genes in the domesticated silkworm, Bombyx mori. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2008; 32:464-75. [PMID: 17499357 DOI: 10.1016/j.dci.2007.03.010] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2007] [Revised: 03/15/2007] [Accepted: 03/19/2007] [Indexed: 05/15/2023]
Abstract
Silkworm (Bombyx mori), a model system for Lepidoptera, has contributed enormously to the study of insect immunology especially in humoral immunity. But little is known about the molecular mechanism of immune response in the silkworm. Toll receptors are a group of evolutionarily ancient proteins, which play a crucial role in the innate immunity of both insects and vertebrates. In human, Toll-like receptors (TLRs) are the typical pattern recognition receptors for different kinds of pathogen molecules. Toll-related receptors in Drosophila, however, were thought to function as cytokine receptors in immune response and embryogenesis. We have identified 11 putative Toll-related receptors and two Toll analogs in the silkworm genome. Phylogenetic analysis of insect Toll family and human TLRs showed that BmTolls is grouped with Drosophila Tolls and Anopheles Tolls. These putative proteins are typical transmembrane receptors flanked by the extracellular leucine-rich repeat (LRR) domain and the cytoplasmic TIR domain. Structural prediction of the TIR domain alignment found five stranded sheets and five helices, which are alternatingly joined. Microarray data indicated that BmToll and BmToll-2 were expressed with remarkable enrichment in the ovary, suggesting that they might play a role in the embryogenesis. However, the enriched expression of BmToll-2 and -4 in the midgut suggested that the proteins they encode may be involved in immune defense. Testis-specific expression of BmToll-10 and -11 and BmToLK-2 implies that these may be involved in sex-specific biological functions. The RT-PCR results indicated that 10 genes were induced or suppressed with different degrees after their immune system was challenged by different invaders. Expression profiles of BmTolls and BmToLKs reported here provide insight into their role in innate immunity and development.
Collapse
Affiliation(s)
- Ting-Cai Cheng
- College of Life Science, Southwest University, Chongqing 400716, China
| | | | | | | | | | | | | |
Collapse
|
85
|
Meng Y, Omuro N, Funaguma S, Daimon T, Kawaoka S, Katsuma S, Shimada T. Prominent down-regulation of storage protein genes after bacterial challenge in eri-silkworm, Samia cynthia ricini. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2008; 67:9-19. [PMID: 18064702 DOI: 10.1002/arch.20214] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We constructed two independent cDNA libraries from the fat body of Escherichia coli- or Candida albicans-challenged eri-silkworm Samia cynthia ricini larvae. We performed comparative expressed sequence tag (EST) analysis of the two cDNA libraries and found that two putative storage protein genes, ScSP1 and ScSP2, were markedly repressed by E. coli injection as compared with C. albicans injection. By quantitative real-time RT-PCR analysis, we showed that ScSP1 mRNA significantly reduced to 1/32-1/3 in the fat body of the female larvae, and ScSP2 mRNA reduced to 1/7-1/3 and 1/22-1/5 in the females and males, respectively, 12-36 h after E. coli injection as compared with PBS injection. In addition, SDS-PAGE analysis revealed that the accumulation of both the ScSP proteins in the larval hemolymph apparently decreased up to 36 h after E. coli injection. However, the amounts of the two ScSP proteins returned to the same level as those in the larvae injected with PBS by 48 h after injection, showing that the reduction in ScSPs caused by the bacterial challenge was transient. Moreover, potential binding sites for the Drosophila Rel/NF-kappaB protein Dorsal were found in the 5' upstream regulatory regions of ScSP1 and ScSP2, suggesting the participation of the Rel/NF-kappaB proteins in controlling the bacterial suppression of the ScSP genes. These results suggested the hypothesis that S. c. ricini has a genetic program to shut down temporarily dispensable gene expression in order to induce an acute and efficient expression of immune-related genes. These findings may provide new insight into the innate immune system in lepidopteran insects.
Collapse
Affiliation(s)
- Yan Meng
- Laboratory of Insect Genetics and Bioscience, Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Science, The University of Tokyo, Tokyo, Japan
| | | | | | | | | | | | | |
Collapse
|
86
|
Gandhe AS, John SH, Nagaraju J. Noduler, A Novel Immune Up-Regulated Protein Mediates Nodulation Response in Insects. THE JOURNAL OF IMMUNOLOGY 2007; 179:6943-51. [DOI: 10.4049/jimmunol.179.10.6943] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
87
|
Herrero S, Ansems M, Van Oers MM, Vlak JM, Bakker PL, de Maagd RA. REPAT, a new family of proteins induced by bacterial toxins and baculovirus infection in Spodoptera exigua. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2007; 37:1109-1118. [PMID: 17916497 DOI: 10.1016/j.ibmb.2007.06.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2007] [Revised: 06/11/2007] [Accepted: 06/12/2007] [Indexed: 05/25/2023]
Abstract
Insect larvae spend most of their time eating and the digestive tract is the most crucial barrier for the entrance of many pathogens. In our study, suppression subtractive hybridization (SSH) was used to compare Spodoptera exigua midgut gene expression between larvae exposed to the Bacillus thuringiensis Cry1Ca toxin and non-exposed insects. Based on the SSH results, full cDNA sequences coding for four homologous proteins were obtained. Quantitative and semi-quantitative RT-PCR showed the increased expression of the genes coding for these proteins after exposure to different B. thuringiensis toxins as well as after infection with baculovirus. The proteins were named REPAT after their increased expression in Response to Pathogen. REPAT1, a member of this family, was recombinantly expressed using the baculovirus expression system, revealing the glycosylated nature of the protein. Recombinant baculoviruses expressing REPAT1 were used to infect larvae from S. exigua, showing that expression of REPAT1 was reducing the virulence of baculovirus to the infected larvae. Together, these results suggest a role for REPAT1 in mitigating pathological effects.
Collapse
Affiliation(s)
- Salvador Herrero
- Business Unit Bioscience, Plant Research International B.V., Wageningen University and Research Centre, Wageningen, The Netherlands.
| | | | | | | | | | | |
Collapse
|
88
|
Girard PA, Boublik Y, Wheat CW, Volkoff AN, Cousserans F, Brehélin M, Escoubas JM. X-tox: an atypical defensin derived family of immune-related proteins specific to Lepidoptera. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2007; 32:575-584. [PMID: 17988734 DOI: 10.1016/j.dci.2007.09.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2007] [Revised: 08/28/2007] [Accepted: 09/27/2007] [Indexed: 05/25/2023]
Abstract
We report here the isolation in Spodoptera frugiperda (Lepidoptera) of an immune-related protein (hereafter named Spod-11-tox), characterized by imperfectly conserved tandem repeats of 11 cysteine-stabilized alpha beta motifs (CS-alphabeta), the structural scaffold characteristic of invertebrate defensins and scorpion toxins. Spod-11-tox orthologs were only found in Lepidopteran species, suggesting that this new protein family (named X-tox) is specific to this insect order. Moreover, phylogenetic analysis suggests that X-tox proteins represent a new class of proteins restricted to Lepidoptera and likely derived from Lepidopteran defensins. In S. frugiperda, analysis of gene expression revealed that spod-11-tox is rapidly induced by infection. However, and conversely to what is known for most insect antimicrobial peptides (AMP), spod-11-tox is mainly expressed in blood cells. Moreover, recombinant Spod-11-tox produced in the Sf9 cell line does not show any antimicrobial activity. Altogether, these results suggest that although X-tox proteins are derived from defensins, they may play a different and still unknown role in Lepidoptera immune response.
Collapse
Affiliation(s)
- Pierre-Alain Girard
- Ecologie Microbienne des Insectes et Interactions Hôte-Pathogène, Université de Montpellier II, 34095 Montpellier, France
| | | | | | | | | | | | | |
Collapse
|
89
|
Eum JH, Seo YR, Yoe SM, Kang SW, Han SS. Analysis of the immune-inducible genes of Plutella xylostella using expressed sequence tags and cDNA microarray. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2007; 31:1107-20. [PMID: 17379306 DOI: 10.1016/j.dci.2007.02.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2005] [Revised: 01/29/2007] [Accepted: 02/07/2007] [Indexed: 05/14/2023]
Abstract
In the present study, the complex gene expression responses of Plutella xylostella to microbial challenges and injury were surveyed using a newly constructed expressed sequence tag (EST) clone collection and cDNA microarray analysis. A total of 1132 P. xylostella ESTs were cloned, annotated and categorized by their putative functions; these included proteases, protease inhibitors, recognition molecules and anti-microbial peptides. GeneOntology revealed that 4% of the P. xylostella ESTs corresponded to immunity-related genes potentially involved in innate immunity. We then used microarray analysis to identify 44 genes that were differentially expressed with at least a two-fold expression difference in P. xylostella before and after pathogen challenge. Together, our EST categorization and microarray profiling analyses allowed us to identify 70 genes that should be considered candidate immune response genes, providing important new insights into the molecular events that occur during the innate immune response in P. xylostella.
Collapse
Affiliation(s)
- Jai Hoon Eum
- Cell Engineering and 3-D Structure Laboratory, School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Republic of Korea
| | | | | | | | | |
Collapse
|
90
|
Wang Y, Cheng T, Rayaprolu S, Zou Z, Xia Q, Xiang Z, Jiang H. Proteolytic activation of pro-spätzle is required for the induced transcription of antimicrobial peptide genes in lepidopteran insects. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2007; 31:1002-12. [PMID: 17337053 PMCID: PMC2020823 DOI: 10.1016/j.dci.2007.01.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2006] [Revised: 01/07/2007] [Accepted: 01/12/2007] [Indexed: 05/13/2023]
Abstract
Microbial infection leads to proteolytic activation of Drosophila spätzle, which binds to the toll receptor and induces the synthesis of immune proteins. To test whether or not this mechanism exists in lepidopteran insects, we cloned the cDNA of Bombyx mori spätzle-1 and overexpressed the full-length and truncated BmSpz1 cDNA in Escherichia coli. The insoluble fusion proteins were affinity-purified under denaturing condition. After the silkworm larvae were injected with renatured BmSpz1, mRNA levels of antimicrobial peptide genes greatly increased. Similar transcriptional up-regulation was also found in Manduca sexta. Injection of pro-BmSpz1 had no such effect. When pro-BmSpz1 and Micrococcus luteus were incubated with the plasma from M. sexta larvae, we detected proteolytic processing of pro-BmSpz1. These results suggest that active spätzle is required for the induced production of antimicrobial peptides in B. mori and M. sexta.
Collapse
Affiliation(s)
- Yang Wang
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK 74078, USA
| | | | | | | | | | | | | |
Collapse
|
91
|
Kerry S, TeKippe M, Gaddis NC, Aballay A. GATA transcription factor required for immunity to bacterial and fungal pathogens. PLoS One 2006; 1:e77. [PMID: 17183709 PMCID: PMC1762309 DOI: 10.1371/journal.pone.0000077] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2006] [Accepted: 11/12/2006] [Indexed: 12/20/2022] Open
Abstract
In the past decade, Caenorhabditis elegans has been used to dissect several genetic pathways involved in immunity; however, little is known about transcription factors that regulate the expression of immune effectors. C. elegans does not appear to have a functional homolog of the key immune transcription factor NF-κB. Here we show that that the intestinal GATA transcription factor ELT-2 is required for both immunity to Salmonella enterica and expression of a C-type lectin gene, clec-67, which is expressed in the intestinal cells and is a good marker of S. enterica infection. We also found that ELT-2 is required for immunity to Pseudomonas aeruginosa, Enterococcus faecalis, and Cryptococcus neoformans. Lack of immune inhibition by DAF-2, which negatively regulates the FOXO transcription factor DAF-16, rescues the hypersusceptibility to pathogens phenotype of elt-2(RNAi) animals. Our results indicate that ELT-2 is part of a multi-pathogen defense pathway that regulates innate immunity independently of the DAF-2/DAF-16 signaling pathway.
Collapse
|
92
|
Gandhe AS, Arunkumar KP, John SH, Nagaraju J. Analysis of bacteria-challenged wild silkmoth, Antheraea mylitta (lepidoptera) transcriptome reveals potential immune genes. BMC Genomics 2006; 7:184. [PMID: 16857061 PMCID: PMC1559613 DOI: 10.1186/1471-2164-7-184] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2006] [Accepted: 07/21/2006] [Indexed: 12/20/2022] Open
Abstract
Background In the recent years a strong resemblance has been observed between the insect immune system and the mammalian innate immune mechanisms suggesting their common origin. Among the insects, only the dipterans (Drosophila and various mosquito species) have been widely investigated for their immune responses towards diverse pathogens. In the present study we constructed and analysed the immune transcriptome of the lepidopteran Antheraea mylitta, an economically important Indian tasar silkmoth with a view to unravel the potential immune-related genes and pathways. Results An expressed sequence tag (EST) library was constructed from mRNA obtained from fat bodies of A. mylitta larvae that had been challenged by infection with Escherichia coli cells. We identified 719 unique ESTs from a total of 1412 sequences so generated. A third of the transcriptome showed similarity with previously characterized immune-related genes that included both the known and putative immune genes. Of the four putative novel defence proteins (DFPs) annotated by PSI-BLAST three showed similarity to extracellular matrix proteins from vertebrates implicated in innate immunity, while the fourth was similar to, yet distinct from, the anti-microbial protein cecropin. Finally, we analysed the expression profiles of 15 potential immune-related genes, and the majority of them were induced more prominently with E. coli compared to Micrococcus luteus. We also identified several unknown proteins, some of which could have probable immune-related functions based on the results of the ProDom analysis. Conclusion The present study has identified many potential immune-related genes in A. mylitta some of which are vertebrate homologues and others are hitherto unreported putative defence proteins. Several genes were present as members of gene families, as has also been observed in other insect species.
Collapse
Affiliation(s)
- Archana S Gandhe
- Laboratory of Molecular Genetics, Centre for DNA Fingerprinting and Diagnostics, ECIL Road, Nacharam, Hyderabad 500076, India
| | - KP Arunkumar
- Laboratory of Molecular Genetics, Centre for DNA Fingerprinting and Diagnostics, ECIL Road, Nacharam, Hyderabad 500076, India
| | - Serene H John
- Laboratory of Molecular Genetics, Centre for DNA Fingerprinting and Diagnostics, ECIL Road, Nacharam, Hyderabad 500076, India
| | - J Nagaraju
- Laboratory of Molecular Genetics, Centre for DNA Fingerprinting and Diagnostics, ECIL Road, Nacharam, Hyderabad 500076, India
| |
Collapse
|