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Holt JR, Cavichiolli de Oliveira N, Medina RF, Malacrinò A, Lindsey ARI. Insect-microbe interactions and their influence on organisms and ecosystems. Ecol Evol 2024; 14:e11699. [PMID: 39041011 PMCID: PMC11260886 DOI: 10.1002/ece3.11699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 06/14/2024] [Accepted: 06/21/2024] [Indexed: 07/24/2024] Open
Abstract
Microorganisms are important associates of insect and arthropod species. Insect-associated microbes, including bacteria, fungi, and viruses, can drastically impact host physiology, ecology, and fitness, while many microbes still have no known role. Over the past decade, we have increased our knowledge of the taxonomic composition and functional roles of insect-associated microbiomes and viromes. There has been a more recent shift toward examining the complexity of microbial communities, including how they vary in response to different factors (e.g., host genome, microbial strain, environment, and time), and the consequences of this variation for the host and the wider ecological community. We provide an overview of insect-microbe interactions, the variety of associated microbial functions, and the evolutionary ecology of these relationships. We explore the influence of the environment and the interactive effects of insects and their microbiomes across trophic levels. Additionally, we discuss the potential for subsequent synergistic and reciprocal impacts on the associated microbiomes, ecological interactions, and communities. Lastly, we discuss some potential avenues for the future of insect-microbe interactions that include the modification of existing microbial symbionts as well as the construction of synthetic microbial communities.
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Affiliation(s)
| | | | - Raul F. Medina
- Department of EntomologyTexas A&M University, Minnie Bell Heep CenterCollege StationTexasUSA
| | - Antonino Malacrinò
- Department of AgricultureUniversità Degli Studi Mediterranea di Reggio CalabriaReggio CalabriaItaly
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2
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Yashima R, Terata Y, Sakamoto K, Watanabe M, Takeshita K. Paraburkholderia largidicola sp. nov., a gut symbiont of the bordered plant bug Physopelta gutta. Int J Syst Evol Microbiol 2024; 74. [PMID: 38832864 DOI: 10.1099/ijsem.0.006411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2024] Open
Abstract
Gram-negative, aerobic, rod-shaped, non-spore-forming, motile bacteria, designated strains F2T and PGU16, were isolated from the midgut crypts of the bordered plant bug Physopelta gutta, collected in Okinawa prefecture, Japan. Although these strains were derived from different host individuals collected at different times, their 16S rRNA gene sequences were identical and showed the highest similarity to Paraburkholderia caribensis MWAP64T (99.3 %). The genome of strain F2T consisted of two chromosomes and two plasmids, and its size and G+C content were 9.28 Mb and 62.4 mol% respectively; on the other hand, that of strain PGU16 consisted of two chromosomes and three plasmids, and its size and G+C content were 9.47 Mb and 62.4 mol%, respectively. Phylogenetic analyses revealed that these two strains are members of the genus Paraburkholderia. The digital DNA-DNA hybridization value between these two strains was 92.4 %; on the other hand, the values between strain F2T and P. caribensis MWAP64T or phylogenetically closely related Paraburkholderia species were 44.3 % or below 49.1 %. The predominant fatty acids of both strains were C16 : 0, C17 : 0 cyclo, summed feature 8 (C18 : 1 ω7c/C18 : 1 ω6c), and C19 : 0 cyclo ω8c, and their respiratory quinone was ubiquinone 8. Based on the above genotypic and phenotypic characteristics, strains F2T and PGU16 represent a novel species of the genus Paraburkholderia for which the name Paraburkholderia largidicola sp. nov. is proposed. The type strain is F2T (=NBRC 115765T=LMG 32765T).
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Affiliation(s)
- Reona Yashima
- Faculty of Bioresource Sciences, Akita Prefectural University, 010-0195 Akita City, Japan
| | - Yuan Terata
- Faculty of Bioresource Sciences, Akita Prefectural University, 010-0195 Akita City, Japan
| | - Kaoru Sakamoto
- Faculty of Bioresource Sciences, Akita Prefectural University, 010-0195 Akita City, Japan
| | - Miho Watanabe
- Faculty of Bioresource Sciences, Akita Prefectural University, 010-0195 Akita City, Japan
| | - Kazutaka Takeshita
- Faculty of Bioresource Sciences, Akita Prefectural University, 010-0195 Akita City, Japan
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3
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Fu S, Chen X, Wang K, Chen J, Zhou J, Yi W, Lyu M, Ye Z, Bu W. Shared phylogeographic patterns and environmental responses of co-distributed soybean pests: Insights from comparative phylogeographic studies of Riptortus pedestris and Riptortus linearis in the subtropics of East Asia. Mol Phylogenet Evol 2024; 195:108055. [PMID: 38485106 DOI: 10.1016/j.ympev.2024.108055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 01/31/2024] [Accepted: 03/07/2024] [Indexed: 03/19/2024]
Abstract
Comparative phylogeographic studies of closely related species sharing co-distribution areas can elucidate the role of shared historical factors and environmental changes in shaping their phylogeographic pattern. The bean bugs, Riptortus pedestris and Riptortus linearis, which both inhabit subtropical regions in East Asia, are recognized as highly destructive soybean pests. Many previous studies have investigated the biological characteristics, pheromones, chemicals and control mechanisms of these two pests, but few studies have explored their phylogeographic patterns and underlying factors. In this study, we generated a double-digest restriction site-associated DNA sequencing (ddRAD-seq) dataset to investigate phylogeographic patterns and construct ecological niche models (ENM) for both Riptortus species. Our findings revealed similar niche occupancies and population genetic structures between the two species, with each comprising two phylogeographic lineages (i.e., the mainland China and the Indochina Peninsula clades) that diverged approximately 0.1 and 0.3 million years ago, respectively. This divergence likely resulted from the combined effects of temperatures variation and geographical barriers in the mountainous regions of Southwest China. Further demographic history and ENM analyses suggested that both pests underwent rapid expansion prior to the Last Glacial Maximum (LGM). Furthermore, ENM predicts a northward shift of both pests into new soybean-producing regions due to global warming. Our study indicated that co-distribution soybean pests with overlapping ecological niches and similar life histories in subtropical regions of East Asia exhibit congruent phylogeographic and demographic patterns in response to shared historical biogeographic drivers.
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Affiliation(s)
- Siying Fu
- College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Xin Chen
- College of Life Sciences, Cangzhou Normal University, Cangzhou, China(2)
| | - Kaibin Wang
- College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Juhong Chen
- College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Jiayue Zhou
- College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Wenbo Yi
- Department of Biology, Xinzhou Normal University, Xinzhou, Shanxi, China(2)
| | - Minhua Lyu
- Nanchang University, Affiliated Hospital 1, Jiangxi, China(2)
| | - Zhen Ye
- College of Life Sciences, Nankai University, Tianjin 300071, China.
| | - Wenjun Bu
- College of Life Sciences, Nankai University, Tianjin 300071, China.
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4
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Ren Y, Fu S, Dong W, Chen J, Xue H, Bu W. The ncRNA-mediated regulatory networks of defensins and lysozymes in Riptortus pedestris: involvement in response to gut bacterial disturbances. Front Microbiol 2024; 15:1386345. [PMID: 38827147 PMCID: PMC11140134 DOI: 10.3389/fmicb.2024.1386345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Accepted: 04/23/2024] [Indexed: 06/04/2024] Open
Abstract
Insects depend on humoral immunity against intruders through the secretion of antimicrobial peptides (AMPs) and immune effectors via NF-κB transcription factors, and their fitness is improved by gut bacterial microbiota. Although there are growing numbers of reports on noncoding RNAs (ncRNAs) involving in immune responses against pathogens, comprehensive studies of ncRNA-AMP regulatory networks in Riptortus pedestris, which is one of the widely distributed pests in East Asia, are still not well understood under feeding environmental changes. The objective of this study employed the whole-transcriptome sequencing (WTS) to systematically identify the lncRNAs (long noncoding RNA) and circRNAs (circular RNA) and to obtain their differential expression from the R. pedestris gut under different feeding conditions. Functional annotation indicated that they were mainly enriched in various biological processes with the GO and KEGG databases, especially in immune signaling pathways. Five defensin (four novel members) and eleven lysozyme (nine novel members) family genes were identified and characterized from WTS data, and meanwhile, phylogenetic analysis confirmed their classification. Subsequently, the miRNA-mRNA interaction network of above two AMPs and lncRNA-involved ceRNA (competing endogenous RNA) regulatory network of one lysozyme were predicted and built based on bioinformatic prediction and calculation, and the expression patterns of differentially expressed (DE) defensins, and DE lysozymes and related DE ncRNAs were estimated and selected among all the comparison groups. Finally, to integrate the analyses of WTS and previous 16S rRNA amplicon sequencing, we conducted the Pearson correlation analysis to reveal the significantly positive or negative correlation between above DE AMPs and ncRNAs, as well as most changes in the gut bacterial microbiota at the genus level of R. pedestris. Taken together, the present observations provide great insights into the ncRNA regulatory networks of AMPs in response to rearing environmental changes in insects and uncover new potential strategies for pest control in the future.
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Affiliation(s)
- Yipeng Ren
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, China
| | - Siying Fu
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, China
| | - Wenhao Dong
- Tianjin Key Laboratory of Food and Biotechnology, School of Biotechnology and Food Science, Tianjin University of Commerce, Tianjin, China
| | - Juhong Chen
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, China
| | - Huaijun Xue
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, China
| | - Wenjun Bu
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, China
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Ludington WB. The importance of host physical niches for the stability of gut microbiome composition. Philos Trans R Soc Lond B Biol Sci 2024; 379:20230066. [PMID: 38497267 PMCID: PMC10945397 DOI: 10.1098/rstb.2023.0066] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 12/04/2023] [Indexed: 03/19/2024] Open
Abstract
Gut bacteria are prevalent throughout the Metazoa and form complex microbial communities associated with food breakdown, nutrient provision and disease prevention. How hosts acquire and maintain a consistent bacterial flora remains mysterious even in the best-studied animals, including humans, mice, fishes, squid, bugs, worms and flies. This essay visits the evidence that hosts have co-evolved relationships with specific bacteria and that some of these relationships are supported by specialized physical niches that select, sequester and maintain microbial symbionts. Genetics approaches could uncover the mechanisms for recruiting and maintaining the stable and consistent members of the microbiome. This article is part of the theme issue 'Sculpting the microbiome: how host factors determine and respond to microbial colonization'.
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Affiliation(s)
- William B. Ludington
- Department of Biosphere Sciences and Engineering, Carnegie Institution for Science, Baltimore, MD 21218, USA
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
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Jang S, Ishigami K, Mergaert P, Kikuchi Y. Ingested soil bacteria breach gut epithelia and prime systemic immunity in an insect. Proc Natl Acad Sci U S A 2024; 121:e2315540121. [PMID: 38437561 PMCID: PMC10945853 DOI: 10.1073/pnas.2315540121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 01/11/2024] [Indexed: 03/06/2024] Open
Abstract
Insects lack acquired immunity and were thought to have no immune memory, but recent studies reported a phenomenon called immune priming, wherein sublethal dose of pathogens or nonpathogenic microbes stimulates immunity and prevents subsequential pathogen infection. Although the evidence for insect immune priming is accumulating, the underlying mechanisms are still unclear. The bean bug Riptortus pedestris acquires its gut microbiota from ambient soil and spatially structures them into a multispecies and variable community in the anterior midgut and a specific, monospecies Caballeronia symbiont population in the posterior region. We demonstrate that a particular Burkholderia strain colonizing the anterior midgut stimulates systemic immunity by penetrating gut epithelia and migrating into the hemolymph. The activated immunity, consisting of a humoral and a cellular response, had no negative effect on the host fitness, but on the contrary protected the insect from subsequent infection by pathogenic bacteria. Interruption of contact between the Burkholderia strain and epithelia of the gut weakened the host immunity back to preinfection levels and made the insects more vulnerable to microbial infection, demonstrating that persistent acquisition of environmental bacteria is important to maintain an efficient immunity.
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Affiliation(s)
- Seonghan Jang
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Hokkaido Center, 062-8517Sapporo, Japan
| | - Kota Ishigami
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Hokkaido Center, 062-8517Sapporo, Japan
| | - Peter Mergaert
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell, 91198Gif-sur-Yvette, France
| | - Yoshitomo Kikuchi
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Hokkaido Center, 062-8517Sapporo, Japan
- Unit of Applied Biological Chemistry, Graduate School of Agriculture, Hokkaido University, 060-8589Sapporo, Japan
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Huang HJ, Li LL, Ye ZX, Lu JB, Lou YH, Wei ZY, Sun ZT, Chen JP, Li JM, Zhang CX. Salivary proteins potentially derived from horizontal gene transfer are critical for salivary sheath formation and other feeding processes. Commun Biol 2024; 7:257. [PMID: 38431762 PMCID: PMC10908841 DOI: 10.1038/s42003-024-05961-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 02/22/2024] [Indexed: 03/05/2024] Open
Abstract
Herbivorous insects employ an array of salivary proteins to aid feeding. However, the mechanisms behind the recruitment and evolution of these genes to mediate plant-insect interactions remain poorly understood. Here, we report a potential horizontal gene transfer (HGT) event from bacteria to an ancestral bug of Eutrichophora. The acquired genes subsequently underwent duplications and evolved through co-option. We annotated them as horizontal-transferred, Eutrichophora-specific salivary protein (HESPs) according to their origin and function. In Riptortus pedestris (Coreoidea), all nine HESPs are secreted into plants during feeding. The RpHESP4 to RpHESP8 are recently duplicated and found to be indispensable for salivary sheath formation. Silencing of RpHESP4-8 increases the difficulty of R. pedestris in probing the soybean, and the treated insects display a decreased survivability. Although silencing the other RpHESPs does not affect the salivary sheath formation, negative effects are also observed. In Pyrrhocoris apterus (Pyrrhocoroidea), five out of six PaHESPs are secretory salivary proteins, with PaHESP3 being critical for insect survival. The PaHESP5, while important for insects, no longer functions as a salivary protein. Our results provide insight into the potential origin of insect saliva and shed light on the evolution of salivary proteins.
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Affiliation(s)
- Hai-Jian Huang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Key Laboratory of Biotechnology in Plant Protection of Ministry of Agriculture and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, 315211, China.
| | - Li-Li Li
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Key Laboratory of Biotechnology in Plant Protection of Ministry of Agriculture and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, 315211, China
| | - Zhuang-Xin Ye
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Key Laboratory of Biotechnology in Plant Protection of Ministry of Agriculture and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, 315211, China
| | - Jia-Bao Lu
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Key Laboratory of Biotechnology in Plant Protection of Ministry of Agriculture and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, 315211, China
| | - Yi-Han Lou
- Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, 310051, China
| | - Zhong-Yan Wei
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Key Laboratory of Biotechnology in Plant Protection of Ministry of Agriculture and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, 315211, China
| | - Zong-Tao Sun
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Key Laboratory of Biotechnology in Plant Protection of Ministry of Agriculture and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, 315211, China
| | - Jian-Ping Chen
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Key Laboratory of Biotechnology in Plant Protection of Ministry of Agriculture and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, 315211, China
| | - Jun-Min Li
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Key Laboratory of Biotechnology in Plant Protection of Ministry of Agriculture and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, 315211, China
| | - Chuan-Xi Zhang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Key Laboratory of Biotechnology in Plant Protection of Ministry of Agriculture and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, 315211, China.
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Michalik A, Bauer E, Szklarzewicz T, Kaltenpoth M. Nutrient supplementation by genome-eroded Burkholderia symbionts of scale insects. THE ISME JOURNAL 2023; 17:2221-2231. [PMID: 37833524 PMCID: PMC10689751 DOI: 10.1038/s41396-023-01528-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Revised: 09/25/2023] [Accepted: 09/28/2023] [Indexed: 10/15/2023]
Abstract
Hemipterans are known as hosts to bacterial or fungal symbionts that supplement their unbalanced diet with essential nutrients. Among them, scale insects (Coccomorpha) are characterized by a particularly large diversity of symbiotic systems. Here, using microscopic and genomic approaches, we functionally characterized the symbionts of two scale insects belonging to the Eriococcidae family, Acanthococcus aceris and Gossyparia spuria. These species host Burkholderia bacteria that are localized in the cytoplasm of the fat body cells. Metagenome sequencing revealed very similar and highly reduced genomes (<900KBp) with a low GC content (~38%), making them the smallest and most AT-biased Burkholderia genomes yet sequenced. In their eroded genomes, both symbionts retain biosynthetic pathways for the essential amino acids leucine, isoleucine, valine, threonine, lysine, arginine, histidine, phenylalanine, and precursors for the semi-essential amino acid tyrosine, as well as the cobalamin-dependent methionine synthase MetH. A tryptophan biosynthesis pathway is conserved in the symbiont of G. spuria, but appeared pseudogenized in A. aceris, suggesting differential availability of tryptophan in the two host species' diets. In addition to the pathways for essential amino acid biosynthesis, both symbionts maintain biosynthetic pathways for multiple cofactors, including riboflavin, cobalamin, thiamine, and folate. The localization of Burkholderia symbionts and their genome traits indicate that the symbiosis between Burkholderia and eriococcids is younger than other hemipteran symbioses, but is functionally convergent. Our results add to the emerging picture of dynamic symbiont replacements in sap-sucking Hemiptera and highlight Burkholderia as widespread and versatile intra- and extracellular symbionts of animals, plants, and fungi.
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Affiliation(s)
- Anna Michalik
- Department of Developmental Biology and Morphology of Invertebrates, Institute of Zoology and Biomedical Research, Faculty of Biology, Jagiellonian University, Krakow, Poland.
| | - Eugen Bauer
- Department for Evolutionary Ecology, Institute for Organismic and Molecular Evolution, Johannes Gutenberg University Mainz, Mainz, Germany
| | - Teresa Szklarzewicz
- Department of Developmental Biology and Morphology of Invertebrates, Institute of Zoology and Biomedical Research, Faculty of Biology, Jagiellonian University, Krakow, Poland
| | - Martin Kaltenpoth
- Department for Evolutionary Ecology, Institute for Organismic and Molecular Evolution, Johannes Gutenberg University Mainz, Mainz, Germany.
- Department of Insect Symbiosis, Max Planck Institute for Chemical Ecology, Jena, Germany.
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Yang ZW, Luo JY, Men Y, Liu ZH, Zheng ZK, Wang YH, Xie Q. Different roles of host and habitat in determining the microbial communities of plant-feeding true bugs. MICROBIOME 2023; 11:244. [PMID: 37932839 PMCID: PMC10629178 DOI: 10.1186/s40168-023-01702-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 10/17/2023] [Indexed: 11/08/2023]
Abstract
BACKGROUND The true bugs (Heteroptera) occupy nearly all of the known ecological niches of insects. Among them, as a group containing more than 30,000 species, the phytophagous true bugs are making increasing impacts on agricultural and forestry ecosystems. Previous studies proved that symbiotic bacteria play important roles in these insects in fitting various habitats. However, it is still obscure about the evolutionary and ecological patterns of the microorganisms of phytophagous true bugs as a whole with comprehensive taxon sampling. RESULTS Here, in order to explore the symbiotic patterns between plant-feeding true bugs and their symbiotic microorganisms, 209 species belonging to 32 families of 9 superfamilies had been sampled, which covered all the major phytophagous families of true bugs. The symbiotic microbial communities were surveyed by full-length 16S rRNA gene and ITS amplicons respectively for bacteria and fungi using the PacBio platform. We revealed that hosts mainly affect the dominant bacteria of symbiotic microbial communities, while habitats generally influence the subordinate ones. Thereafter, we carried out the ancestral state reconstruction of the dominant bacteria and found that dramatic replacements of dominant bacteria occurred in the early Cretaceous and formed newly stable symbiotic relationships accompanying the radiation of insect families. In contrast, the symbiotic fungi were revealed to be horizontally transmitted, which makes fungal communities distinctive in different habitats but not significantly related to hosts. CONCLUSIONS Host and habitat determine microbial communities of plant-feeding true bugs in different roles. The symbiotic bacterial communities are both shaped by host and habitat but in different ways. Nevertheless, the symbiotic fungal communities are mainly influenced by habitat but not host. These findings shed light on a general framework for future microbiome research of phytophagous insects. Video Abstract.
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Affiliation(s)
- Zi-Wen Yang
- School of Life Sciences, State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, 510275, Guangdong, China
| | - Jiu-Yang Luo
- School of Life Sciences, State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, 510275, Guangdong, China
| | - Yu Men
- School of Life Sciences, Zhaoqing University, Zhaoqing, 526061, China
| | - Zhi-Hui Liu
- School of Life Sciences, State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, 510275, Guangdong, China
| | - Zi-Kai Zheng
- School of Life Sciences, State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, 510275, Guangdong, China
| | - Yan-Hui Wang
- School of Life Sciences, State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, 510275, Guangdong, China
| | - Qiang Xie
- School of Life Sciences, State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, 510275, Guangdong, China.
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Gook DH, Jung M, Kim S, Lee DH. Species diversity of environmentally-transmitted bacteria colonizing Riptortus pedestris (Hemiptera: Alydidae) and symbiotic effects of the most dominant bacteria. Sci Rep 2023; 13:15166. [PMID: 37704685 PMCID: PMC10499786 DOI: 10.1038/s41598-023-42419-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 09/10/2023] [Indexed: 09/15/2023] Open
Abstract
Riptortus pedestris (Hemiptera: Alydidae) establish endosymbiosis with specific bacteria from extremely diverse microbiota in soil. To better understand ecology and evolution of the symbiosis, it is important to characterize bacterial species diversity colonizing R. pedestris and evaluate their symbiotic effects. Nonetheless, previous research was limited to a few bacteria strains such as Caballeronia insecticola. In this study, second-instar nymphs were provided with field soils and reared to adult. Then, bacteria colonizing the midgut M4 region of R. pedestris were analyzed for bacterial species identification based on the 16S rRNA gene. First, a total of 15 bacterial species were detected belonging to Burkholderiaceae. Most of R. pedestris were found to harbor single bacterial species, whereas several insects harbored at most two bacterial species simultaneously. Among the total insects harboring single bacterial species, 91.2% harbored genus Caballeronia. The most dominant species was C. jiangsuensis, not previously documented for symbiotic associations with R. pedestris. Second, in laboratory conditions, C. jiangsuensis significantly enhanced the development, body size, and reproductive potentials of R. pedestris, compared to individuals with no symbiotic bacteria. These results add novel information to better understand symbiotic bacteria community establishing in R. pedestris and symbiotic effects on the host insects.
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Affiliation(s)
- Do-Hun Gook
- Department of Life Sciences, Gachon University, Seongnam-daero 1342, Seongnam-si, Gyeonggi-do, South Korea
| | - Minhyung Jung
- Department of Life Sciences, Gachon University, Seongnam-daero 1342, Seongnam-si, Gyeonggi-do, South Korea
| | - Soowan Kim
- Department of Life Sciences, Gachon University, Seongnam-daero 1342, Seongnam-si, Gyeonggi-do, South Korea
| | - Doo-Hyung Lee
- Department of Life Sciences, Gachon University, Seongnam-daero 1342, Seongnam-si, Gyeonggi-do, South Korea.
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Jang S, Matsuura Y, Ishigami K, Mergaert P, Kikuchi Y. Symbiont coordinates stem cell proliferation, apoptosis, and morphogenesis of gut symbiotic organ in the stinkbug- Caballeronia symbiosis. Front Physiol 2023; 13:1071987. [PMID: 36685208 PMCID: PMC9846216 DOI: 10.3389/fphys.2022.1071987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 12/16/2022] [Indexed: 01/05/2023] Open
Abstract
The bean bug Riptortus pedestris obtains a specific bacterial symbiont, Caballeronia insecticola (Burkholderia insecticola), from the environmental soil and harbors it in the posterior midgut region that is composed of hundreds of crypts. While newly hatched aposymbiotic insects possess primordial midgut crypts with little or no lumen, colonization of C. insecticola triggers swift development of the symbiotic organ, forming enlarged and opened crypts, and the symbiont subsequently fills the luminal cavities of those mature crypts. The cellular processes of crypt development triggered by C. insecticola colonization are poorly understood. Here we identified a fundamental mechanism of the symbiont-mediated midgut development by investigating cell cycles of intestinal epithelial cells. Intestinal stem cells of the bean bug are located and proliferate at the crypt base. Differentiated enterocytes migrate upward along the epithelial cell layer of the crypt as the midgut develops, induction of apoptosis in enterocytes primarily occurred on the tip side of the crypts, and apoptotic cells then eventually were shed from the crypts into the hemolymph. The proliferation rate of the stem cells at the base of the crypts was low while a high apoptotic rate was observed at the crypt tip in aposymbiotic insects, resulting in undeveloped short crypts. On the contrary, the gut-colonizing C. insecticola promoted the proliferation of the stem cells at the base of crypts and simultaneously inhibited apoptosis at the tip of crypts, resulting in a net growth of the crypts and the generation of a crypt lumen that becomes colonized by the bacterial symbiont. These results demonstrated that the Caballeronia symbiont colonization induces the development of the midgut crypts via finely regulating the enterocyte cell cycles, enabling it to stably and abundantly colonize the generated spacious crypts of the bean bug host.
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Affiliation(s)
- Seonghan Jang
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology, Hokkaido Center, Sapporo, Japan,Division of Life Sciences, Korea Polar Research Institute, Incheon, South Korea,*Correspondence: Seonghan Jang, ; Yoshitomo Kikuchi,
| | - Yu Matsuura
- Tropical Biosphere Research Center, University of the Ryukyus, Nishihara, Okinawa, Japan
| | - Kota Ishigami
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology, Hokkaido Center, Sapporo, Japan,Graduate School of Agriculture, Hokkaido University, Sapporo, Japan
| | - Peter Mergaert
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Yoshitomo Kikuchi
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology, Hokkaido Center, Sapporo, Japan,Graduate School of Agriculture, Hokkaido University, Sapporo, Japan,*Correspondence: Seonghan Jang, ; Yoshitomo Kikuchi,
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12
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Alarcón ME, Polo PG, Akyüz SN, Rafiqi AM. Evolution and ontogeny of bacteriocytes in insects. Front Physiol 2022; 13:1034066. [PMID: 36505058 PMCID: PMC9732443 DOI: 10.3389/fphys.2022.1034066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 11/11/2022] [Indexed: 11/26/2022] Open
Abstract
The ontogenetic origins of the bacteriocytes, which are cells that harbour bacterial intracellular endosymbionts in multicellular animals, are unknown. During embryonic development, a series of morphological and transcriptional changes determine the fate of distinct cell types. The ontogeny of bacteriocytes is intimately linked with the evolutionary transition of endosymbionts from an extracellular to an intracellular environment, which in turn is linked to the diet of the host insect. Here we review the evolution and development of bacteriocytes in insects. We first classify the endosymbiotic occupants of bacteriocytes, highlighting the complex challenges they pose to the host. Then, we recall the historical account of the discovery of bacteriocytes. We then summarize the molecular interactions between the endosymbiont and the host. In addition, we illustrate the genetic contexts in which the bacteriocytes develop, with examples of the genetic changes in the hosts and endosymbionts, during specific endosymbiotic associations. We finally address the evolutionary origin as well as the putative ontogenetic or developmental source of bacteriocytes in insects.
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13
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Kakizawa S, Hosokawa T, Oguchi K, Miyakoshi K, Fukatsu T. Spiroplasma as facultative bacterial symbionts of stinkbugs. Front Microbiol 2022; 13:1044771. [PMID: 36353457 PMCID: PMC9638005 DOI: 10.3389/fmicb.2022.1044771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 10/07/2022] [Indexed: 12/05/2022] Open
Abstract
Many insects are associated with facultative symbiotic bacteria, and their infection prevalence provides an important clue to understand the biological impact of such microbial associates. Here we surveyed diverse stinkbugs representing 13 families, 69 genera, 97 species and 468 individuals for Spiroplasma infection. Diagnostic PCR detection revealed that 4 families (30.8%), 7 genera (10.1%), 11 species (11.3%) and 21 individuals (4.5%) were Spiroplasma positive. All the 21 stinkbug samples with Spiroplasma infection were subjected to PCR amplification and sequencing of Spiroplasma’s 16S rRNA gene. Molecular phylogenetic analysis uncovered that the stinkbug-associated Spiroplasma symbionts were placed in three distinct clades in the Spiroplasmataceae, highlighting multiple evolutionary origins of the stinkbug-Spiroplasma associations. The Spiroplasma phylogeny did not reflect the host stinkbug phylogeny, indicating the absence of host-symbiont co-speciation. On the other hand, the Spiroplasma symbionts associated with the same stinkbug family tended to be related to each other, suggesting the possibility of certain levels of host-symbiont specificity and/or ecological symbiont sharing. Amplicon sequencing analysis targeting bacterial 16S rRNA gene, FISH visualization of the symbiotic bacteria, and rearing experiments of the host stinkbugs uncovered that the Spiroplasma symbionts are generally much less abundant in comparison with the primary gut symbiotic bacteria, localized to various tissues and organs at relatively low densities, and vertically transmitted to the offspring. On the basis of these results, we conclude that the Spiroplasma symbionts are, in general, facultative bacterial associates of low infection prevalence that are not essential but rather commensalistic for the host stinkbugs, like the Spiroplasma symbionts of fruit flies and aphids, although their impact on the host phenotypes should be evaluated in future studies.
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Affiliation(s)
- Shigeyuki Kakizawa
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
- *Correspondence: Shigeyuki Kakizawa, ; Takema Fukatsu,
| | - Takahiro Hosokawa
- Department of Biology, Faculty of Science, Kyushu University, Fukuoka, Japan
| | - Kohei Oguchi
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
- Misaki Marine Biological Station (MMBS), School of Science, The University of Tokyo, Miura, Japan
| | - Kaori Miyakoshi
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | - Takema Fukatsu
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
- Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
- *Correspondence: Shigeyuki Kakizawa, ; Takema Fukatsu,
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14
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Ishigami K, Jang S, Itoh H, Kikuchi Y. Obligate Gut Symbiotic Association with Caballeronia in the Mulberry Seed Bug Paradieuches dissimilis (Lygaeoidea: Rhyparochromidae). MICROBIAL ECOLOGY 2022:10.1007/s00248-022-02117-2. [PMID: 36178538 DOI: 10.1007/s00248-022-02117-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 09/22/2022] [Indexed: 06/16/2023]
Abstract
Many insects possess symbiotic bacteria in their bodies, and microbial symbionts play pivotal metabolic roles for their hosts. Members of the heteropteran superfamilies Coreoidea and Lygaeoidea stinkbugs harbor symbionts of the genus Caballeronia in their intestinal tracts. Compared with symbiotic associations in Coreoidea, those in Lygaeoidea insects are still less understood. Here, we investigated a symbiotic relationship involving the mulberry seed bug Paradieuches dissimilis (Lygaeoidea: Rhyparochromidae) using histological observations, cultivation of the symbiont, 16S rRNA gene amplicon sequencing, and infection testing of cultured symbionts. Histological observations and cultivation revealed that P. dissimilis harbors Caballeronia symbionts in the crypts of its posterior midgut. 16S rRNA gene amplicon sequencing of field-collected P. dissimilis confirmed that the genus Caballeronia is dominant in the midgut of natural populations of P. dissimilis. In addition, PCR diagnostics showed that the eggs were free of symbiotic bacteria, and hatchlings horizontally acquired the symbionts from ambient soil. Infection and rearing experiments revealed that symbiont-free aposymbiotic individuals had abnormal body color, small body size, and, strikingly, a low survival rate, wherein no individuals reached adulthood, indicating an obligate cooperative mutualism between the mulberry seed bug and Caballeronia symbionts.
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Affiliation(s)
- Kota Ishigami
- Graduate School of Agriculture, Hokkaido University, Sapporo, 060-8589, Japan
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Hokkaido Center, Sapporo, 062-8517, Japan
| | - Seonghan Jang
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Hokkaido Center, Sapporo, 062-8517, Japan.
- Division of Life Sciences, Korea Polar Research Institute, Incheon, 21990, Republic of Korea.
| | - Hideomi Itoh
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Hokkaido Center, Sapporo, 062-8517, Japan
| | - Yoshitomo Kikuchi
- Graduate School of Agriculture, Hokkaido University, Sapporo, 060-8589, Japan
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Hokkaido Center, Sapporo, 062-8517, Japan
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15
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Heras J, Martin CH. Minimal overall divergence of the gut microbiome in an adaptive radiation of Cyprinodon pupfishes despite potential adaptive enrichment for scale-eating. PLoS One 2022; 17:e0273177. [PMID: 36112615 PMCID: PMC9481044 DOI: 10.1371/journal.pone.0273177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 08/03/2022] [Indexed: 11/18/2022] Open
Abstract
Adaptive radiations offer an excellent opportunity to understand the eco-evolutionary dynamics of gut microbiota and host niche specialization. In a laboratory common garden, we compared the gut microbiota of two novel derived trophic specialist pupfishes, a scale-eater and a molluscivore, to closely related and distant outgroup generalist populations, spanning both rapid trophic evolution within 10 kya and stable generalist diets persisting over 11 Mya. We predicted an adaptive and highly divergent microbiome composition in the trophic specialists reflecting their rapid rates of craniofacial and behavioral diversification. We sequenced 16S rRNA amplicons of gut microbiomes from lab-reared adult pupfishes raised under identical conditions and fed the same high protein diet. In contrast to our predictions, gut microbiota largely reflected phylogenetic distance among species, rather than generalist or specialist life history, in support of phylosymbiosis. However, we did find significant enrichment of Burkholderiaceae bacteria in replicated lab-reared scale-eater populations. These bacteria sometimes digest collagen, the major component of fish scales, supporting an adaptive shift. We also found some enrichment of Rhodobacteraceae and Planctomycetia in lab-reared molluscivore populations, but these bacteria target cellulose. Overall phylogenetic conservation of microbiome composition contrasts with predictions of adaptive radiation theory and observations of rapid diversification in all other trophic traits in these hosts, including craniofacial morphology, foraging behavior, aggression, and gene expression, suggesting that the functional role of these minor shifts in microbiota will be important for understanding the role of the microbiome in trophic diversification.
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Affiliation(s)
- Joseph Heras
- Department of Integrative Biology, University of California, Berkeley, Berkeley, CA, United States of America
- Museum of Vertebrate Zoology, University of California, Berkeley, Berkeley, CA, United States of America
- * E-mail:
| | - Christopher H. Martin
- Department of Integrative Biology, University of California, Berkeley, Berkeley, CA, United States of America
- Museum of Vertebrate Zoology, University of California, Berkeley, Berkeley, CA, United States of America
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16
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Ohbayashi T, Cossard R, Lextrait G, Hosokawa T, Lesieur V, Takeshita K, Tago K, Mergaert P, Kikuchi Y. Intercontinental Diversity of Caballeronia Gut Symbionts in the Conifer Pest Bug Leptoglossus occidentalis. Microbes Environ 2022; 37. [PMID: 35965097 PMCID: PMC9530724 DOI: 10.1264/jsme2.me22042] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Many stinkbugs in the superfamily Coreoidea (Hemiptera: Heteroptera) develop crypts in the posterior midgut, harboring Caballeronia (Burkholderia) symbionts. These symbionts form a monophyletic group in Burkholderia sensu lato, called the “stinkbug-associated beneficial and environmental (SBE)” group, recently reclassified as the new genus Caballeronia. SBE symbionts are separated into the subclades SBE-α and SBE-β. Previous studies suggested a regional effect on the symbiont infection pattern; Japanese and American bug species are more likely to be associated with SBE-α, while European bug species are almost exclusively associated with SBE-β. However, since only a few insect species have been investigated, it remains unclear whether region-specific infection is general. We herein investigated Caballeronia gut symbionts in diverse Japanese, European, and North American populations of a cosmopolitan species, the Western conifer seed bug Leptoglossus occidentalis (Coreoidea: Coreidae). A molecular phylogenetic analysis of the 16S rRNA gene demonstrated that SBE-β was the most dominant in all populations. Notably, SBE-α was rarely detected in any region, while a third clade, the “Coreoidea clade” occupied one fourth of the tested populations. Although aposymbiotic bugs showed high mortality, SBE-α- and SBE-β-inoculated insects both showed high survival rates; however, a competition assay demonstrated that SBE-β outcompeted SBE-α in the midgut crypts of L. occidentalis. These results strongly suggest that symbiont specificity in the Leptoglossus-Caballeronia symbiotic association is influenced by the host rather than geography, while the geographic distribution of symbionts may be more important in other bugs.
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Affiliation(s)
- Tsubasa Ohbayashi
- Institute for Agro-Environmental Sciences, National Agriculture and Food Research Organization (NARO).,Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC)
| | - Raynald Cossard
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC)
| | - Gaëlle Lextrait
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC)
| | | | | | | | - Kanako Tago
- Institute for Agro-Environmental Sciences, National Agriculture and Food Research Organization (NARO)
| | - Peter Mergaert
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC)
| | - Yoshitomo Kikuchi
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Hokkaido Center.,Graduate School of Agriculture, Hokkaido University
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17
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Shell WA, Rehan SM. Comparative metagenomics reveals expanded insights into intra- and interspecific variation among wild bee microbiomes. Commun Biol 2022; 5:603. [PMID: 35715496 PMCID: PMC9205906 DOI: 10.1038/s42003-022-03535-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 05/26/2022] [Indexed: 11/17/2022] Open
Abstract
The holobiont approach proposes that species are most fully understood within the context of their associated microbiomes, and that both host and microbial community are locked in a mutual circuit of co-evolutionary selection. Bees are an ideal group for this approach, as they comprise a critical group of pollinators that contribute to both ecological and agricultural health worldwide. Metagenomic analyses offer comprehensive insights into an organism’s microbiome, diet, and viral load, but remain largely unapplied to wild bees. Here, we present metagenomic data from three species of carpenter bees sampled from around the globe, representative of the first ever carpenter bee core microbiome. Machine learning, co-occurrence, and network analyses reveal that wild bee metagenomes are unique to host species. Further, we find that microbiomes are likely strongly affected by features of their local environment, and feature evidence of plant pathogens previously known only in honey bees. Performing the most comprehensive comparative analysis of bee microbiomes to date we discover that microbiome diversity is inversely proportional to host species social complexity. Our study helps to establish some of the first wild bee hologenomic data while offering powerful empirical insights into the biology and health of vital pollinators. Global wild bee metagenomes provide insights into microbiome, sociality and pollinator health.
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Affiliation(s)
- Wyatt A Shell
- Department of Biology, York University, Toronto, ON, Canada
| | - Sandra M Rehan
- Department of Biology, York University, Toronto, ON, Canada.
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18
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Abstract
A huge number of bacterial species are motile by flagella, which allow them to actively move toward favorable environments and away from hazardous areas and to conquer new habitats. The general perception of flagellum-mediated movement and chemotaxis is dominated by the Escherichia coli paradigm, with its peritrichous flagellation and its famous run-and-tumble navigation pattern, which has shaped the view on how bacteria swim and navigate in chemical gradients. However, a significant amount-more likely the majority-of bacterial species exhibit a (bi)polar flagellar localization pattern instead of lateral flagella. Accordingly, these species have evolved very different mechanisms for navigation and chemotaxis. Here, we review the earlier and recent findings on the various modes of motility mediated by polar flagella. Expected final online publication date for the Annual Review of Microbiology, Volume 76 is September 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Kai M Thormann
- Institute of Microbiology and Molecular Biology, Justus Liebig University Gießen, Gießen, Germany;
| | - Carsten Beta
- Institute of Physics and Astronomy, University of Potsdam, Potsdam, Germany;
| | - Marco J Kühn
- Institute of Bioengineering and Global Health Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland;
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19
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Han Y, Zhang X, Liu P, Xu S, Chen D, Liu JN, Xie W. Microplastics exposure causes oxidative stress and microbiota dysbiosis in planarian Dugesia japonica. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:28973-28983. [PMID: 34994935 DOI: 10.1007/s11356-022-18547-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 01/03/2022] [Indexed: 05/10/2023]
Abstract
Planarians are widely used as water quality indicator species to provide early warning of harmful pollution in aquatic ecosystems. However, the impact of microplastics on freshwater planarians remains poorly investigated. Here we simulated waterborne microplastic exposure in the natural environments to examine the effect on the antioxidant defense system and microbiota in Dugesia japonica. The results showed that exposure to microplastics significantly changed the levels of antioxidant enzymes, including superoxide dismutase, catalase, and glutathione S-transferase, indicating that microplastic exposure induces oxidative stress in planarians. High-throughput 16S rRNA gene sequencing results revealed that exposure to microplastics altered the diversity, abundance, and composition of planarian microbiota community. At phylum level, the relative abundance of the dominant phyla Proteobacteria and Bacteroidetes changed significantly after microplastic exposure. At genus level, the abundance of dominant genera also changed significantly, including Curvibacter and unclassified Chitinophagales. Predictive functional analysis showed that the microbiota of microplastic-exposed planarians exhibited an enrichment in genes related to fatty acid metabolism. Overall, these results showed that microplastics can cause oxidative stress and microbiota dysbiosis in planarians, indicating that planarians can serve as an indicator species for microplastic pollution in freshwater systems.
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Affiliation(s)
- Yapeng Han
- College of Life Sciences, Longdong University, Qingyang745000, Gansu, China.
- Gansu Key Laboratory of Conservation and Utilization of Biological Resources and Ecological Restoration in Longdong Area, Qingyang 745000, Gansu, China.
| | - Xiaoxia Zhang
- Central Blood Station of Qingyang, Qingyang 745000, Gansu, China
| | - Pengfei Liu
- College of Life Sciences, Longdong University, Qingyang745000, Gansu, China
- Gansu Key Laboratory of Conservation and Utilization of Biological Resources and Ecological Restoration in Longdong Area, Qingyang 745000, Gansu, China
| | - Shujuan Xu
- College of Life Sciences, Longdong University, Qingyang745000, Gansu, China
- Gansu Key Laboratory of Conservation and Utilization of Biological Resources and Ecological Restoration in Longdong Area, Qingyang 745000, Gansu, China
| | - Delai Chen
- College of Life Sciences, Longdong University, Qingyang745000, Gansu, China
- Gansu Key Laboratory of Conservation and Utilization of Biological Resources and Ecological Restoration in Longdong Area, Qingyang 745000, Gansu, China
| | - Jian Ning Liu
- College of Forestry, Shandong Agricultural University, Tai'an 271018, Shandong, China.
| | - Wenguang Xie
- Sanya Institute, Hainan Academy of Agricultural Sciences, Sanya 572024, Hainan, China
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20
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Unzueta-Martínez A, Welch H, Bowen JL. Determining the Composition of Resident and Transient Members of the Oyster Microbiome. Front Microbiol 2022; 12:828692. [PMID: 35185836 PMCID: PMC8847785 DOI: 10.3389/fmicb.2021.828692] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 12/27/2021] [Indexed: 01/04/2023] Open
Abstract
To better understand how complex microbial communities become assembled on eukaryotic hosts, it is essential to disentangle the balance between stochastic and deterministic processes that drive their assembly. Deterministic processes can create consistent patterns of microbiome membership that result in persistent resident communities, while stochastic processes can result in random fluctuation of microbiome members that are transient with regard to their association to the host. We sampled oyster reefs from six different populations across the east coast of the United States. At each site we collected gill tissues for microbial community analysis and additionally collected and shipped live oysters to Northeastern University where they were held in a common garden experiment. We then examined the microbiome shifts in gill tissues weekly for 6 weeks using 16S rRNA gene amplicon sequencing. We found a strong population-specific signal in the microbial community composition of field-sampled oysters. Surprisingly, the oysters sampled during the common garden experiment maintained compositionally distinct gill-associated microbial communities that reflected their wild population of origin, even after rearing them in a common garden for several weeks. This indicates that oyster gill-associated microbiota are predominantly composed of resident microbes specific to host population, rather than being a reflection of their immediate biotic and abiotic surroundings. However, certain bacterial taxa tended to appear more frequently on individuals from different populations than on individuals from the same population, indicating that there is a small portion of the gill microbiome that is transient and is readily exchanged with the environmental pool of microbes. Regardless, the majority of gill-associated microbes were resident members that were specific to each oyster population, suggesting that there are strong deterministic factors that govern a large portion of the gill microbiome. A small portion of the microbial communities, however, was transient and moved among oyster populations, indicating that stochastic assembly also contributes to the oyster gill microbiome. Our results are relevant to the oyster aquaculture industry and oyster conservation efforts because resident members of the oyster microbiome may represent microbes that are important to oyster health and some of these key members vary depending on oyster population.
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Affiliation(s)
- Andrea Unzueta-Martínez
- Department of Marine and Environmental Sciences, Northeastern University, Nahant, MA, United States
| | - Heather Welch
- Department of Marine and Environmental Sciences, Northeastern University, Nahant, MA, United States
| | - Jennifer L Bowen
- Department of Marine and Environmental Sciences, Northeastern University, Nahant, MA, United States
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21
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Pons I, Scieur N, Dhondt L, Renard ME, Renoz F, Hance T. Pervasiveness of the symbiont Serratia symbiotica in the aphid natural environment: distribution, diversity and evolution at a multitrophic level. FEMS Microbiol Ecol 2022; 98:6526308. [PMID: 35142841 DOI: 10.1093/femsec/fiac012] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 01/05/2022] [Accepted: 02/08/2022] [Indexed: 11/12/2022] Open
Abstract
Symbioses are significant drivers of insect evolutionary ecology. Despite recent findings that these associations can emerge from environmentally derived bacterial precursors, there is still little information on how these potential progenitors of insect symbionts circulate in trophic systems. Serratia symbiotica represents a valuable model for deciphering evolutionary scenarios of bacterial acquisition by insects, as its diversity includes gut-associated strains that retained the ability to live independently of their hosts, representing a potential reservoir for symbioses emergence. Here, we conducted a field study to examine the distribution and diversity of S. symbiotica found in aphid populations, and in different compartments of their surrounding environment. Twenty % of aphids colonies were infected with S. symbiotica, including a wide diversity of strains with varied tissue tropism corresponding to different lifestyle. We also showed that the prevalence of S. symbiotica is influenced by seasonal temperatures. We found that S. symbiotica was present in non-aphid species and in host plants, and that its prevalence in these samples was higher when associated aphid colonies were infected. Furthermore, phylogenetic analyses suggest the existence of horizontal transfers between the different trophic levels. These results provide a new picture of the pervasiveness of an insect symbiont in nature.
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Affiliation(s)
- Inès Pons
- Earth and Life Institute, Biodiversity Research Centre, Université catholique de Louvain, 1348, Louvain-la-Neuve, Belgium
| | - Nora Scieur
- Earth and Life Institute, Biodiversity Research Centre, Université catholique de Louvain, 1348, Louvain-la-Neuve, Belgium
| | - Linda Dhondt
- Earth and Life Institute, Biodiversity Research Centre, Université catholique de Louvain, 1348, Louvain-la-Neuve, Belgium
| | - Marie-Eve Renard
- Earth and Life Institute, Biodiversity Research Centre, Université catholique de Louvain, 1348, Louvain-la-Neuve, Belgium
| | - François Renoz
- Earth and Life Institute, Biodiversity Research Centre, Université catholique de Louvain, 1348, Louvain-la-Neuve, Belgium
| | - Thierry Hance
- Earth and Life Institute, Biodiversity Research Centre, Université catholique de Louvain, 1348, Louvain-la-Neuve, Belgium
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22
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Sato Y, Jang S, Takeshita K, Itoh H, Koike H, Tago K, Hayatsu M, Hori T, Kikuchi Y. Insecticide resistance by a host-symbiont reciprocal detoxification. Nat Commun 2021; 12:6432. [PMID: 34741016 PMCID: PMC8571283 DOI: 10.1038/s41467-021-26649-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 10/13/2021] [Indexed: 02/03/2023] Open
Abstract
Insecticide resistance is one of the most serious problems in contemporary agriculture and public health. Although recent studies revealed that insect gut symbionts contribute to resistance, the symbiont-mediated detoxification process remains unclear. Here we report the in vivo detoxification process of an organophosphorus insecticide, fenitrothion, in the bean bug Riptortus pedestris. Using transcriptomics and reverse genetics, we reveal that gut symbiotic bacteria degrade this insecticide through a horizontally acquired insecticide-degrading enzyme into the non-insecticidal but bactericidal compound 3-methyl-4-nitrophenol, which is subsequently excreted by the host insect. This integrated "host-symbiont reciprocal detoxification relay" enables the simultaneous maintenance of symbiosis and efficient insecticide degradation. We also find that the symbiont-mediated detoxification process is analogous to the insect genome-encoded fenitrothion detoxification system present in other insects. Our findings highlight the capacity of symbiosis, combined with horizontal gene transfer in the environment, as a powerful strategy for an insect to instantly eliminate a toxic chemical compound, which could play a critical role in the human-pest arms race.
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Affiliation(s)
- Yuya Sato
- Environmental Management Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Center, 305-8569, Tsukuba, Japan
| | - Seonghan Jang
- Graduate School of Agriculture, Hokkaido University, 060-8589, Sapporo, Japan
| | - Kazutaka Takeshita
- Faculty of Bioresource Sciences, Akita Prefectural University, 010-0195, Akita, Japan
| | - Hideomi Itoh
- Bioproduction Research Institute, AIST, Hokkaido Center, 062-8517, Sapporo, Japan
| | - Hideaki Koike
- Bioproduction Research Institute, AIST, Tsukuba Center, 305-8566, Tsukuba, Japan
| | - Kanako Tago
- Institute for Agro-Environmental Sciences, National Agriculture and Food Research Organization (NARO), 305-8604, Tsukuba, Japan
| | - Masahito Hayatsu
- Institute for Agro-Environmental Sciences, National Agriculture and Food Research Organization (NARO), 305-8604, Tsukuba, Japan
| | - Tomoyuki Hori
- Environmental Management Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Center, 305-8569, Tsukuba, Japan
| | - Yoshitomo Kikuchi
- Graduate School of Agriculture, Hokkaido University, 060-8589, Sapporo, Japan. .,Bioproduction Research Institute, AIST, Hokkaido Center, 062-8517, Sapporo, Japan.
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23
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Fu W, Liu X, Rao C, Ji R, Bing X, Li J, Wang Y, Xu H. Screening Candidate Effectors of the Bean Bug Riptortus pedestris by Proteomic and Transcriptomic Analyses. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.760368] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The damage of Riptortus pedestris is exceptional by leading soybean plants to keep green in late autumn. Identification of the salivary proteins is essential to understand how the pest-plant interaction occurs. Here, we have tried to identify them by a combination of proteomic and transcriptomic analyses. The transcriptomes of salivary glands from R. pedestris males, females and nymphs showed about 28,000 unigenes, in which about 40% had open reading frames (ORFs). Therefore, the predicted proteins in the transcriptomes with secretion signals were obtained. Many of the top 1,000 expressed transcripts were involved in protein biosynthesis and transport, suggesting that the salivary glands produce a rich repertoire of proteins. In addition, saliva of R. pedestris males, females and nymphs was collected and proteins inside were identified. In total, 155, 20, and 11 proteins were, respectively, found in their saliva. We have tested the tissue-specific expression of 68 genes that are likely to be effectors, either because they are homologs of reported effectors of other sap-feeding arthropods, or because they are within the top 1,000 expressed genes or found in the salivary proteomes. Their potential functions in regulating plant defenses were discussed. The datasets reported here represent the first step in identifying effectors of R. pedestris.
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24
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Dual oxidase enables insect gut symbiosis by mediating respiratory network formation. Proc Natl Acad Sci U S A 2021; 118:2020922118. [PMID: 33649233 DOI: 10.1073/pnas.2020922118] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Most animals harbor a gut microbiota that consists of potentially pathogenic, commensal, and mutualistic microorganisms. Dual oxidase (Duox) is a well described enzyme involved in gut mucosal immunity by the production of reactive oxygen species (ROS) that antagonizes pathogenic bacteria and maintains gut homeostasis in insects. However, despite its nonspecific harmful activity on microorganisms, little is known about the role of Duox in the maintenance of mutualistic gut symbionts. Here we show that, in the bean bug Riptortus pedestris, Duox-dependent ROS did not directly contribute to epithelial immunity in the midgut in response to its mutualistic gut symbiont, Burkholderia insecticola Instead, we found that the expression of Duox is tracheae-specific and its down-regulation by RNAi results in the loss of dityrosine cross-links in the tracheal protein matrix and a collapse of the respiratory system. We further demonstrated that the establishment of symbiosis is a strong oxygen sink triggering the formation of an extensive network of tracheae enveloping the midgut symbiotic organ as well as other organs, and that tracheal breakdown by Duox RNAi provokes a disruption of the gut symbiosis. Down-regulation of the hypoxia-responsive transcription factor Sima or the regulators of tracheae formation Trachealess and Branchless produces similar phenotypes. Thus, in addition to known roles in immunity and in the formation of dityrosine networks in diverse extracellular matrices, Duox is also a crucial enzyme for tracheal integrity, which is crucial to sustain mutualistic symbionts and gut homeostasis. We expect that this is a conserved function in insects.
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25
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Huang HJ, Ye YX, Ye ZX, Yan XT, Wang X, Wei ZY, Chen JP, Li JM, Sun ZT, Zhang CX. Chromosome-level genome assembly of the bean bug Riptortus pedestris. Mol Ecol Resour 2021; 21:2423-2436. [PMID: 34038033 DOI: 10.1111/1755-0998.13434] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 05/16/2021] [Accepted: 05/20/2021] [Indexed: 12/21/2022]
Abstract
The bean bug (Riptortus pedestris) causes great economic losses of soybeans by piercing and sucking pods and seeds. Although R. pedestris has become the focus of numerous studies associated with insect-microbe interactions, plant-insect interactions, and pesticide resistance, a lack of genomic resources has limited deeper insights. Here, we report the first R. pedestris genome at the chromosomal level using PacBio, Illumina, and Hi-C technologies. The assembled genome was 1.080 Gb in size with a contig N50 of 2.882 Mb. More than 96.3% of the total genome bases were successfully anchored to six unique chromosomes. Genome resequencing of male and female individuals and chromosomic staining demonstrated that the sex chromosome system of R. pedestris is XO, and the shortest chromosome is the X chromosome. In total, 19,026 protein-coding genes were predicted, 18,745 of which were validated as being expressed. Temporospatial expression of R. pedestris genes in six tissues and 37 development stages revealed 4,657 and 7,793 genes mainly expressed in gonads and egg periods, respectively. Evolutionary analysis demonstrated that R. pedestris and Oncopeltus fasciatus formed a sister group and split ∼80 million years ago (Mya). Additionally, a 5.04 Mb complete genome of symbiotic Serratia marcescens Rip1 was assembled, and the virulence factors that account for successful colonization in the host midgut were identified. The high-quality R. pedestris genome provides a valuable resource for further research, as well as for the pest management of bug pests.
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Affiliation(s)
- Hai-Jian Huang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Key Laboratory of Biotechnology in Plant Protection of MOA of China and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, China
| | - Yu-Xuan Ye
- Institute of Insect Science, Zhejiang University, Hangzhou, China
| | - Zhuang-Xin Ye
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Key Laboratory of Biotechnology in Plant Protection of MOA of China and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, China
| | - Xiao-Tian Yan
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Key Laboratory of Biotechnology in Plant Protection of MOA of China and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, China
| | - Xin Wang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Key Laboratory of Biotechnology in Plant Protection of MOA of China and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, China
| | - Zhong-Yan Wei
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Key Laboratory of Biotechnology in Plant Protection of MOA of China and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, China
| | - Jian-Ping Chen
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Key Laboratory of Biotechnology in Plant Protection of MOA of China and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, China
| | - Jun-Min Li
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Key Laboratory of Biotechnology in Plant Protection of MOA of China and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, China
| | - Zong-Tao Sun
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Key Laboratory of Biotechnology in Plant Protection of MOA of China and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, China
| | - Chuan-Xi Zhang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Key Laboratory of Biotechnology in Plant Protection of MOA of China and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, China
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26
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Zilber-Rosenberg I, Rosenberg E. Microbial driven genetic variation in holobionts. FEMS Microbiol Rev 2021; 45:6261188. [PMID: 33930136 DOI: 10.1093/femsre/fuab022] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 04/11/2021] [Indexed: 12/11/2022] Open
Abstract
Genetic variation in holobionts, (host and microbiome), occurring by changes in both host and microbiome genomes, can be observed from two perspectives: observable variations and the processes that bring about the variation. The observable includes the enormous genetic diversity of prokaryotes, which gave rise to eukaryotic organisms. Holobionts then evolved a rich microbiome with a stable core containing essential genes, less so common taxa, and a more diverse non-core enabling considerable genetic variation. The result being that, the human gut microbiome, for example, contains 1,000 times more unique genes than are present in the human genome. Microbial driven genetic variation processes in holobionts include: (1) Acquisition of novel microbes from the environment, which bring in multiple genes in one step, (2) amplification/reduction of certain microbes in the microbiome, that contribute to holobiont` s adaptation to changing conditions, (3) horizontal gene transfer between microbes and between microbes and host, (4) mutation, which plays an important role in optimizing interactions between different microbiota and between microbiota and host. We suggest that invertebrates and plants, where microbes can live intracellularly, have a greater chance of genetic exchange between microbiota and host, thus a greater chance of vertical transmission and a greater effect of microbiome on evolution of host than vertebrates. However, even in vertebrates the microbiome can aid in environmental fluctuations by amplification/reduction and by acquisition of novel microorganisms.
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Affiliation(s)
- Ilana Zilber-Rosenberg
- Department of Molecular Microbiology and Biotechnology, Tel Aviv University, Ramat Aviv Israel
| | - Eugene Rosenberg
- Department of Molecular Microbiology and Biotechnology, Tel Aviv University, Ramat Aviv Israel
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27
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Ishigami K, Jang S, Itoh H, Kikuchi Y. Insecticide resistance governed by gut symbiosis in a rice pest, Cletus punctiger, under laboratory conditions. Biol Lett 2021; 17:20200780. [PMID: 33653096 DOI: 10.1098/rsbl.2020.0780] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Resistance to toxins in insects is generally thought of as their own genetic trait, but recent studies have revealed that gut microorganisms could mediate resistance by detoxifying phytotoxins and man-made insecticides. By laboratory experiments, we here discovered a striking example of gut symbiont-mediated insecticide resistance in a serious rice pest, Cletus punctiger. The rice bug horizontally acquired fenitrothion-degrading Burkholderia through oral infection and housed it in midgut crypts. Fenitrothion-degradation test revealed that the gut-colonizing Burkholderia retains a high degrading activity of the organophosphate compound in the insect gut. This gut symbiosis remarkably increased resistance against fenitrothion treatment in the host rice bug. Considering that many stinkbug pests are associated with soil-derived Burkholderia, our finding strongly supports that a number of stinkbug species could gain resistance against insecticide simply by acquiring insecticide-degrading gut bacteria.
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Affiliation(s)
- Kota Ishigami
- Graduate School of Agriculture, Hokkaido University, 060-8589 Sapporo, Japan.,Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Hokkaido Center, 062-8517 Sapporo, Japan
| | - Seonghan Jang
- Graduate School of Agriculture, Hokkaido University, 060-8589 Sapporo, Japan.,Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Hokkaido Center, 062-8517 Sapporo, Japan
| | - Hideomi Itoh
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Hokkaido Center, 062-8517 Sapporo, Japan
| | - Yoshitomo Kikuchi
- Graduate School of Agriculture, Hokkaido University, 060-8589 Sapporo, Japan.,Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Hokkaido Center, 062-8517 Sapporo, Japan
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28
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The Gut Microbiota of the Insect Infraorder Pentatomomorpha (Hemiptera: Heteroptera) for the Light of Ecology and Evolution. Microorganisms 2021; 9:microorganisms9020464. [PMID: 33672230 PMCID: PMC7926433 DOI: 10.3390/microorganisms9020464] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 02/18/2021] [Accepted: 02/19/2021] [Indexed: 01/05/2023] Open
Abstract
The stinkbugs of the infraorder Pentatomomorpha are a group of important plant sap-feeding insects, which host diverse microorganisms. Some are located in their complex morphological midgut compartments, while some within the specialized bacteriomes of insect hosts. This perpetuation of symbioses through host generations is reinforced via the diverse routes of vertical transmission or environmental acquisition of the symbionts. These symbiotic partners, reside either through the extracellular associations in midgut or intracellular associations in specialized cells, not only have contributed nutritional benefits to the insect hosts but also shaped their ecological and evolutionary basis. The stinkbugs and gut microbe symbioses present a valuable model that provides insights into symbiotic interactions between agricultural insects and microorganisms and may become potential agents for insect pest management.
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29
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Bosch TCG, McFall-Ngai M. Animal development in the microbial world: Re-thinking the conceptual framework. Curr Top Dev Biol 2021; 141:399-427. [PMID: 33602495 PMCID: PMC8214508 DOI: 10.1016/bs.ctdb.2020.11.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Animals have evolved within the framework of the microbes and are constantly exposed to diverse microbiota. This dominance of the microbial world is forcing all fields of biology to question some of their most basic premises, with developmental biology being no exception. While animals under laboratory conditions can develop and live without microbes, they are far from normal, and would not survive under natural conditions, where their fitness would be strongly compromised. Since much of the undescribed biodiversity on Earth is microbial, any consideration of animal development in the absence of the recognition of microbes will be incomplete. Here, we show that animal development may never have been autonomous, rather it requires transient or persistent interactions with the microbial world. We propose that to formulate a comprehensive understanding of embryogenesis and post-embryonic development, we must recognize that symbiotic microbes provide important developmental signals and contribute in significant ways to phenotype production. This offers limitless opportunities for the field of developmental biology to expand.
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Affiliation(s)
- Thomas C G Bosch
- Zoological Institute, Christian-Albrechts-University Kiel, Kiel, Germany.
| | - Margaret McFall-Ngai
- Pacific Biosciences Research Center, Kewalo Marine Laboratory, University of Hawai'i at Mānoa, Honolulu, HI, United States
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30
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Bijnens K, Thijs S, Leynen N, Stevens V, McAmmond B, Van Hamme J, Vangronsveld J, Artois T, Smeets K. Differential effect of silver nanoparticles on the microbiome of adult and developing planaria. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2021; 230:105672. [PMID: 33227667 DOI: 10.1016/j.aquatox.2020.105672] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 10/04/2020] [Accepted: 10/27/2020] [Indexed: 05/23/2023]
Abstract
Silver nanoparticles (AgNPs) are widely incorporated in household, consumer and medical products. Their unintentional release via wastewaters raises concerns on their environmental impact, particularly for aquatic organisms and their associated bacterial communities. It is known that the microbiome plays an important role in its host's health and physiology, e.g. by producing essential nutrients and providing protection against pathogens. A thorough understanding of the effects of AgNPs on bacterial communities and on their interactions with the host is crucial to fully assess AgNP toxicity on aquatic organisms. Our results indicate that the microbiome of the invertebrate Schmidtea mediterranea, a freshwater planarian, is affected by AgNP exposure at the tested 10 μg/ml concentration. Using targeted amplification of the bacterial 16S rRNA gene V3-V4 region, two independent experiments on the microbiomes of adult worms revealed a consistent decrease in Betaproteobacteriales after AgNP exposure, mainly attributed to a decrease in Curvibacter and Undibacterium. Although developing tissues and organisms are known to be more sensitive to toxic compounds, three independent experiments in regenerating worms showed a less pronounced effect of AgNP exposure on the microbiome, possibly because underlying bacterial community changes during development mask the AgNP induced effect. The presence of a polyvinyl-pyrrolidone (PVP) coating did not significantly alter the outcome of the experiments compared to those with uncoated particles. The observed variation between the different experiments underlines the highly variable nature of microbiomes and emphasises the need to repeat microbiome experiments, within and between physiological states of the animal.
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Affiliation(s)
- Karolien Bijnens
- Centre for Environmental Sciences, Zoology, Biodiversity and Toxicology, Hasselt University, Hasselt, Belgium
| | - Sofie Thijs
- Centre for Environmental Sciences, Environmental Biology, Hasselt University, Hasselt, Belgium
| | - Nathalie Leynen
- Centre for Environmental Sciences, Zoology, Biodiversity and Toxicology, Hasselt University, Hasselt, Belgium
| | - Vincent Stevens
- Centre for Environmental Sciences, Environmental Biology, Hasselt University, Hasselt, Belgium
| | - Breanne McAmmond
- Department of Biological Sciences, Thompson Rivers University, Kamloops, British Columbia, Canada
| | - Jonathan Van Hamme
- Department of Biological Sciences, Thompson Rivers University, Kamloops, British Columbia, Canada
| | - Jaco Vangronsveld
- Centre for Environmental Sciences, Environmental Biology, Hasselt University, Hasselt, Belgium; Department of Plant Physiology, Faculty of Biology and Biotechnology, Maria Skłodowska-Curie University, Lublin, Poland
| | - Tom Artois
- Centre for Environmental Sciences, Zoology, Biodiversity and Toxicology, Hasselt University, Hasselt, Belgium
| | - Karen Smeets
- Centre for Environmental Sciences, Zoology, Biodiversity and Toxicology, Hasselt University, Hasselt, Belgium.
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31
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Multiple origins of obligate nematode and insect symbionts by a clade of bacteria closely related to plant pathogens. Proc Natl Acad Sci U S A 2020; 117:31979-31986. [PMID: 33257562 DOI: 10.1073/pnas.2000860117] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Obligate symbioses involving intracellular bacteria have transformed eukaryotic life, from providing aerobic respiration and photosynthesis to enabling colonization of previously inaccessible niches, such as feeding on xylem and phloem, and surviving in deep-sea hydrothermal vents. A major challenge in the study of obligate symbioses is to understand how they arise. Because the best studied obligate symbioses are ancient, it is especially challenging to identify early or intermediate stages. Here we report the discovery of a nascent obligate symbiosis in Howardula aoronymphium, a well-studied nematode parasite of Drosophila flies. We have found that H aoronymphium and its sister species harbor a maternally inherited intracellular bacterial symbiont. We never find the symbiont in nematode-free flies, and virtually all nematodes in the field and the laboratory are infected. Treating nematodes with antibiotics causes a severe reduction in fly infection success. The association is recent, as more distantly related insect-parasitic tylenchid nematodes do not host these endosymbionts. We also report that the Howardula nematode symbiont is a member of a widespread monophyletic group of invertebrate host-associated microbes that has independently given rise to at least four obligate symbioses, one in nematodes and three in insects, and that is sister to Pectobacterium, a lineage of plant pathogenic bacteria. Comparative genomic analysis of this group, which we name Candidatus Symbiopectobacterium, shows signatures of genome erosion characteristic of early stages of symbiosis, with the Howardula symbiont's genome containing over a thousand predicted pseudogenes, comprising a third of its genome.
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32
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McFall-Ngai M, Bosch TCG. Animal development in the microbial world: The power of experimental model systems. Curr Top Dev Biol 2020; 141:371-397. [PMID: 33602493 PMCID: PMC8211120 DOI: 10.1016/bs.ctdb.2020.10.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The development of powerful model systems has been a critical strategy for understanding the mechanisms underlying the progression of an animal through its ontogeny. Here we provide two examples that allow deep and mechanistic insight into the development of specific animal systems. Species of the cnidarian genus Hydra have provided excellent models for studying host-microbe interactions and how metaorganisms function in vivo. Studies of the Hawaiian bobtail squid Euprymna scolopes and its luminous bacterial partner Vibrio fischeri have been used for over 30 years to understand the impact of a broad array of levels, from ecology to genomics, on the development and persistence of symbiosis. These examples provide an integrated perspective of how developmental processes work and evolve within the context of a microbial world, a new view that opens vast horizons for developmental biology research. The Hydra and the squid systems also lend an example of how profound insights can be discovered by taking advantage of the "experiments" that evolution had done in shaping conserved developmental processes.
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Affiliation(s)
- Margaret McFall-Ngai
- Pacific Biosciences Research Center, Kewalo Marine Laboratory, University of Hawai'i at Mānoa, Honolulu, HI, United States.
| | - Thomas C G Bosch
- Zoological Institute, Christian-Albrechts-University Kiel, Kiel, Germany
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33
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Goto S, Ohbayashi T, Takeshita K, Sone T, Matsuura Y, Mergaert P, Kikuchi Y. A Peptidoglycan Amidase Mutant of Burkholderia insecticola Adapts an L-form-like Shape in the Gut Symbiotic Organ of the Bean Bug Riptortus pedestris. Microbes Environ 2020; 35. [PMID: 33177277 PMCID: PMC7734397 DOI: 10.1264/jsme2.me20107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Bacterial cell shapes may be altered by the cell cycle, nutrient availability, environmental stress, and interactions with other organisms. The bean bug Riptortus pedestris possesses a symbiotic bacterium, Burkholderia insecticola, in its midgut crypts. This symbiont is a typical rod-shaped bacterium under in vitro culture conditions, but changes to a spherical shape inside the gut symbiotic organ of the host insect, suggesting the induction of morphological alterations in B. insecticola by host factors. The present study revealed that a deletion mutant of a peptidoglycan amidase gene (amiC), showing a filamentous chain form in vitro, adapted a swollen L-form-like cell shape in midgut crypts. Spatiotemporal observations of the ΔamiC mutant in midgut crypts revealed the induction of swollen cells, particularly prior to the molting of insects. To elucidate the mechanisms underlying in vivo-specific morphological alterations, the symbiont was cultured under 13 different conditions and its cell shape was examined. Swollen cells, similar to symbiont cells in midgut crypts, were induced when the mutant was treated with fosfomycin, an inhibitor of peptidoglycan precursor biosynthesis. Collectively, these results strongly suggest that the Burkholderia symbiont in midgut crypts is under the control of the host insect via a cell wall-attacking agent.
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Affiliation(s)
- Shiori Goto
- Graduate School of Agriculture, Hokkaido University
| | - Tsubasa Ohbayashi
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC).,Institute for Agro-Environmental Sciences, National Agriculture and Food Research Organization (NARO)
| | | | - Teruo Sone
- Research Faculty of Agriculture, Hokkaido University
| | - Yu Matsuura
- Tropical Biosphere Research Center, University of the Ryukyus
| | - Peter Mergaert
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC)
| | - Yoshitomo Kikuchi
- Graduate School of Agriculture, Hokkaido University.,Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Hokkaido Center
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34
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Arévalo-Cortés A, Mejia-Jaramillo AM, Granada Y, Coatsworth H, Lowenberger C, Triana-Chavez O. The Midgut Microbiota of Colombian Aedes aegypti Populations with Different Levels of Resistance to the Insecticide Lambda-cyhalothrin. INSECTS 2020; 11:insects11090584. [PMID: 32882829 PMCID: PMC7565445 DOI: 10.3390/insects11090584] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 08/11/2020] [Accepted: 08/24/2020] [Indexed: 12/12/2022]
Abstract
Insecticide resistance in Aedes aegypti populations is a problem that hinders vector control and dengue prevention programs. In this study, we determined the susceptibility of Ae. aegypti populations from six Colombian regions to the pyrethroid lambda-cyhalothrin and evaluated the presence of the V1016I mutation in the sodium channel gene, which has been broadly involved in the resistance to this insecticide. The diversity of the gut microbiota of these mosquito populations was also analyzed. Only mosquitoes from Bello were susceptible to lambda-cyhalothrin and presented a lower allelic frequency of the V1016I mutation. Remarkably, there was not an important change in allelic frequencies among populations with different resistance ratios, indicating that other factors or mechanisms contributed to the resistant phenotype. Treatment of mosquitoes with antibiotics led us to hypothesize that the intestinal microbiota could contribute to the resistance to lambda-cyhalothrin. Beta diversity analysis showed significant differences in the species of bacteria present between susceptible and resistant populations. We identified 14 OTUs of bacteria that were unique in resistant mosquitoes. We propose that kdr mutations are important in the development of resistance to lambda-cyhalothrin at low insecticide concentrations but insect symbionts could play an essential role in the metabolization of pyrethroid insecticides at higher concentrations, contributing to the resistant phenotype in Ae. aegypti.
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Affiliation(s)
- Andrea Arévalo-Cortés
- Group Biología y Control de Enfermedades Infecciosas, Universidad de Antioquia, Calle 70 No. 52-21, Medellín 050010, Colombia; (A.A.-C.); (A.M.M.-J.); (Y.G.)
| | - Ana M. Mejia-Jaramillo
- Group Biología y Control de Enfermedades Infecciosas, Universidad de Antioquia, Calle 70 No. 52-21, Medellín 050010, Colombia; (A.A.-C.); (A.M.M.-J.); (Y.G.)
| | - Yurany Granada
- Group Biología y Control de Enfermedades Infecciosas, Universidad de Antioquia, Calle 70 No. 52-21, Medellín 050010, Colombia; (A.A.-C.); (A.M.M.-J.); (Y.G.)
| | - Heather Coatsworth
- Centre for Cell Biology, Development, and Disease, Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada; (H.C.); (C.L.)
| | - Carl Lowenberger
- Centre for Cell Biology, Development, and Disease, Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada; (H.C.); (C.L.)
| | - Omar Triana-Chavez
- Group Biología y Control de Enfermedades Infecciosas, Universidad de Antioquia, Calle 70 No. 52-21, Medellín 050010, Colombia; (A.A.-C.); (A.M.M.-J.); (Y.G.)
- Correspondence: ; Tel.: +57-4-219-6520
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Douglas AE. Housing microbial symbionts: evolutionary origins and diversification of symbiotic organs in animals. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190603. [PMID: 32772661 DOI: 10.1098/rstb.2019.0603] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
In many animal hosts, microbial symbionts are housed within specialized structures known as symbiotic organs, but the evolutionary origins of these structures have rarely been investigated. Here, I adopt an evolutionary developmental (evo-devo) approach, specifically to apply knowledge of the development of symbiotic organs to gain insights into their evolutionary origins and diversification. In particular, host genetic changes associated with evolution of symbiotic organs can be inferred from studies to identify the host genes that orchestrate the development of symbiotic organs, recognizing that microbial products may also play a key role in triggering the developmental programme in some associations. These studies may also reveal whether higher animal taxonomic groups (order, class, phylum, etc.) possess a common genetic regulatory network for symbiosis that is latent in taxa lacking symbiotic organs, and activated at the origination of symbiosis in different host lineages. In this way, apparent instances of convergent evolution of symbiotic organs may be homologous in terms of a common genetic blueprint for symbiosis. Advances in genetic technologies, including reverse genetic tools and genome editing, will facilitate the application of evo-devo approaches to investigate the evolution of symbiotic organs in animals. This article is part of the theme issue 'The role of the microbiome in host evolution'.
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Affiliation(s)
- Angela E Douglas
- Department of Entomology and Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
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Ravenscraft A, Thairu MW, Hansen AK, Hunter MS. Continent-Scale Sampling Reveals Fine-Scale Turnover in a Beneficial Bug Symbiont. Front Microbiol 2020; 11:1276. [PMID: 32636818 PMCID: PMC7316890 DOI: 10.3389/fmicb.2020.01276] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 05/19/2020] [Indexed: 12/05/2022] Open
Abstract
Many members of animal-associated microbial communities, including the gut flora, are acquired from their host’s environment. While many of these communities are species rich, some true bugs (Hemiptera) in the superfamilies Lygaeoidea and Coreidae allow only ingested Burkholderia to colonize and reproduce in a large portion of the midgut. We studied the spatial structuring of Burkholderia associated with a widespread omnivorous bug genus, Jalysus (Berytidae). We sampled Wickham’s stilt bug, Jalysus wickhami, across the United States and performed limited sampling of its sister species, the spined stilt bug Jalysus spinosus. We asked: (1) What Burkholderia strains are hosted by Jalysus at different locations? (2) Does host insect species, host plant species, or location influence the strain these insects acquire? (3) How does Burkholderia affect the development and reproductive fitness of J. wickhami? We found: (1) Sixty-one Burkholderia strains were present across a sample of 352 individuals, but one strain dominated, accounting for almost half of all symbiont reads. Most strains were closely related to other hemipteran Burkholderia symbionts. (2) Many individuals hosted more than one strain of Burkholderia. (3) J. wickhami and J. spinosus did not differ in the strains they hosted. (4) Insects that fed on different plant species tended to host different Burkholderia, but this accounted for only 4% of the variation in strains hosted. In contrast, the location at which an insect was collected explained 27% of the variation in symbiont strains. (5) Burkholderia confers important fitness benefits to J. wickhami. In laboratory experiments, aposymbiotic (Burkholderia-free) insects developed more slowly and laid fewer eggs than symbiotic (Burkholderia-colonized) insects. (6) In the lab, nymphs sometimes acquired Burkholderia via indirect exposure to adults, indicating that horizontal symbiont transmission can occur via adult insect-mediated enrichment of Burkholderia in the local environment – a phenomenon not previously reported in bug-Burkholderia relationships. Taken together, the results suggest that for these bugs, critical nutritional requirements are outsourced to a highly diverse and spatially structured collection of Burkholderia strains acquired from the environment and, occasionally, from conspecific adults.
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Affiliation(s)
- Alison Ravenscraft
- Center for Insect Science, University of Arizona, Tucson, AZ, United States
| | - Margaret W Thairu
- Department of Entomology, University of California, Riverside, Riverside, CA, United States
| | - Allison K Hansen
- Department of Entomology, University of California, Riverside, Riverside, CA, United States
| | - Martha S Hunter
- Department of Entomology, University of Arizona, Tucson, AZ, United States
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Genomic Comparison of Insect Gut Symbionts from Divergent Burkholderia Subclades. Genes (Basel) 2020; 11:genes11070744. [PMID: 32635398 PMCID: PMC7397029 DOI: 10.3390/genes11070744] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 06/29/2020] [Accepted: 07/01/2020] [Indexed: 01/01/2023] Open
Abstract
Stink bugs of the superfamilies Coreoidea and Lygaeoidea establish gut symbioses with environmentally acquired bacteria of the genus Burkholderia sensu lato. In the genus Burkholderia, the stink bug-associated strains form a monophyletic clade, named stink bug-associated beneficial and environmental (SBE) clade (or Caballeronia). Recently, we revealed that members of the family Largidae of the superfamily Pyrrhocoroidea are associated with Burkholderia but not specifically with the SBE Burkholderia; largid bugs harbor symbionts that belong to a clade of plant-associated group of Burkholderia, called plant-associated beneficial and environmental (PBE) clade (or Paraburkholderia). To understand the genomic features of Burkholderia symbionts of stink bugs, we isolated two symbiotic Burkholderia strains from a bordered plant bug Physopellta gutta (Pyrrhocoroidea: Largidae) and determined their complete genomes. The genome sizes of the insect-associated PBE (iPBE) are 9.5 Mb and 11.2 Mb, both of which are larger than the genomes of the SBE Burkholderia symbionts. A whole-genome comparison between two iPBE symbionts and three SBE symbionts highlighted that all previously reported symbiosis factors are shared and that 282 genes are specifically conserved in the five stink bug symbionts, over one-third of which have unknown function. Among the symbiont-specific genes, about 40 genes formed a cluster in all five symbionts; this suggests a "symbiotic island" in the genome of stink bug-associated Burkholderia.
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Burkholderia insecticola triggers midgut closure in the bean bug Riptortus pedestris to prevent secondary bacterial infections of midgut crypts. ISME JOURNAL 2020; 14:1627-1638. [PMID: 32203122 DOI: 10.1038/s41396-020-0633-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2019] [Revised: 03/03/2020] [Accepted: 03/10/2020] [Indexed: 02/06/2023]
Abstract
In addition to abiotic triggers, biotic factors such as microbial symbionts can alter development of multicellular organisms. Symbiont-mediated morphogenesis is well-investigated in plants and marine invertebrates but rarely in insects despite the enormous diversity of insect-microbe symbioses. The bean bug Riptortus pedestris is associated with Burkholderia insecticola which are acquired from the environmental soil and housed in midgut crypts. To sort symbionts from soil microbiota, the bean bug develops a specific organ called the "constricted region" (CR), a narrow and symbiont-selective channel, located in the midgut immediately upstream of the crypt-bearing region. In this study, inoculation of fluorescent protein-labeled symbionts followed by spatiotemporal microscopic observations revealed that after the initial passage of symbionts through the CR, it closes within 12-18 h, blocking any potential subsequent infection events. The "midgut closure" developmental response was irreversible, even after symbiont removal from the crypts by antibiotics. It never occurred in aposymbiotic insects, nor in insects infected with nonsymbiotic bacteria or B. insecticola mutants unable to cross the CR. However, species of the genus Burkholderia and its outgroup Pandoraea that can pass the CR and partially colonize the midgut crypts induce the morphological alteration, suggesting that the molecular trigger signaling the midgut closure is conserved in this bacterial lineage. We propose that this drastic and quick alteration of the midgut morphology in response to symbiont infection is a mechanism for stabilizing the insect-microbe gut symbiosis and contributes to host-symbiont specificity in a symbiosis without vertical transmission.
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Complete Genome Sequence of Burkholderia sp. Strain THE68, a Bacterial Symbiont Isolated from Midgut Crypts of the Seed Bug Togo hemipterus. Microbiol Resour Announc 2020; 9:9/10/e00041-20. [PMID: 32139565 PMCID: PMC7171205 DOI: 10.1128/mra.00041-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Burkholderia sp. strain THE68 is a bacterial symbiont isolated from the midgut crypts of a phytophagous stink bug, Togo hemipterus Here, we report the complete 7.98-Mb genome of this symbiont, which consists of six circular replicons containing 7,238 protein coding genes.
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Kaltenpoth M, Flórez LV. Versatile and Dynamic Symbioses Between Insects and Burkholderia Bacteria. ANNUAL REVIEW OF ENTOMOLOGY 2020; 65:145-170. [PMID: 31594411 DOI: 10.1146/annurev-ento-011019-025025] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Symbiotic associations with microorganisms represent major sources of ecological and evolutionary innovations in insects. Multiple insect taxa engage in symbioses with bacteria of the genus Burkholderia, a diverse group that is widespread across different environments and whose members can be mutualistic or pathogenic to plants, fungi, and animals. Burkholderia symbionts provide nutritional benefits and resistance against insecticides to stinkbugs, defend Lagria beetle eggs against pathogenic fungi, and may be involved in nitrogen metabolism in ants. In contrast to many other insect symbioses, the known associations with Burkholderia are characterized by environmental symbiont acquisition or mixed-mode transmission, resulting in interesting ecological and evolutionary dynamics of symbiont strain composition. Insect-Burkholderia symbioses present valuable model systems from which to derive insights into general principles governing symbiotic interactions because they are often experimentally and genetically tractable and span a large fraction of the diversity of functions, localizations, and transmission routes represented in insect symbioses.
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Affiliation(s)
- Martin Kaltenpoth
- Institute of Organismic and Molecular Evolution, Evolutionary Ecology, Johannes Gutenberg University Mainz, 55128 Mainz, Germany; ,
| | - Laura V Flórez
- Institute of Organismic and Molecular Evolution, Evolutionary Ecology, Johannes Gutenberg University Mainz, 55128 Mainz, Germany; ,
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Haselkorn TS, DiSalvo S, Miller JW, Bashir U, Brock DA, Queller DC, Strassmann JE. The specificity of Burkholderia symbionts in the social amoeba farming symbiosis: Prevalence, species, genetic and phenotypic diversity. Mol Ecol 2019; 28:847-862. [PMID: 30575161 DOI: 10.1111/mec.14982] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 10/13/2018] [Accepted: 10/25/2018] [Indexed: 01/10/2023]
Abstract
The establishment of symbioses between eukaryotic hosts and bacterial symbionts in nature is a dynamic process. The formation of such relationships depends on the life history of both partners. Bacterial symbionts of amoebae may have unique evolutionary trajectories to the symbiont lifestyle, because bacteria are typically ingested as prey. To persist after ingestion, bacteria must first survive phagocytosis. In the social amoeba Dictyostelium discoideum, certain strains of Burkholderia bacteria are able to resist amoebal digestion and maintain a persistent relationship that includes carriage throughout the amoeba's social cycle that culminates in spore formation. Some Burkholderia strains allow their host to carry other bacteria, as food. This carried food is released in new environments in a trait called farming. To better understand the diversity and prevalence of Burkholderia symbionts and the traits they impart to their amoebae hosts, we first screened 700 natural isolates of D. discoideum and found 25% infected with Burkholderia. We next used a multilocus phylogenetic analysis and identified two independent transitions by Burkholderia to the symbiotic lifestyle. Finally, we tested the ability of 38 strains of Burkholderia from D. discoideum, as well as strains isolated from other sources, for traits relevant to symbiosis in D. discoideum. Only D. discoideum native isolates belonging to the Burkholderia agricolaris, B. hayleyella, and B. bonniea species were able to form persistent symbiotic associations with D. discoideum. The Burkholderia-Dictyostelium relationship provides a promising arena for further studies of the pathway to symbiosis in a unique system.
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Affiliation(s)
| | - Susanne DiSalvo
- Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, Illinois
| | - Jacob W Miller
- Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, Illinois
| | - Usman Bashir
- Department of Biology, Washington University in St. Louis, Missouri
| | - Debra A Brock
- Department of Biology, Washington University in St. Louis, Missouri
| | - David C Queller
- Department of Biology, Washington University in St. Louis, Missouri
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Host-symbiont specificity determined by microbe-microbe competition in an insect gut. Proc Natl Acad Sci U S A 2019; 116:22673-22682. [PMID: 31636183 DOI: 10.1073/pnas.1912397116] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Despite the omnipresence of specific host-symbiont associations with acquisition of the microbial symbiont from the environment, little is known about how the specificity of the interaction evolved and is maintained. The bean bug Riptortus pedestris acquires a specific bacterial symbiont of the genus Burkholderia from environmental soil and harbors it in midgut crypts. The genus Burkholderia consists of over 100 species, showing ecologically diverse lifestyles, and including serious human pathogens, plant pathogens, and nodule-forming plant mutualists, as well as insect mutualists. Through infection tests of 34 Burkholderia species and 18 taxonomically diverse bacterial species, we demonstrate here that nonsymbiotic Burkholderia and even its outgroup Pandoraea could stably colonize the gut symbiotic organ and provide beneficial effects to the bean bug when inoculated on aposymbiotic hosts. However, coinoculation revealed that the native symbiont always outcompeted the nonnative bacteria inside the gut symbiotic organ, explaining the predominance of the native Burkholderia symbiont in natural bean bug populations. Hence, the abilities for colonization and cooperation, usually thought of as specific traits of mutualists, are not unique to the native Burkholderia symbiont but, to the contrary, competitiveness inside the gut is a derived trait of the native symbiont lineage only and was thus critical in the evolution of the insect gut symbiont.
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Kuechler SM, Fukatsu T, Matsuura Y. Repeated evolution of bacteriocytes in lygaeoid stinkbugs. Environ Microbiol 2019; 21:4378-4394. [PMID: 31573127 DOI: 10.1111/1462-2920.14804] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Accepted: 09/13/2019] [Indexed: 02/06/2023]
Abstract
Host-microbe symbioses often evolved highly complex developmental processes and colonization mechanisms for establishment of stable associations. It has long been recognized that many insects harbour beneficial bacteria inside specific symbiotic cells (bacteriocytes) or organs (bacteriomes). However, the evolutionary origin and mechanisms underlying bacterial colonization in bacteriocyte/bacteriome formation have been poorly understood. In order to uncover the origin of such evolutionary novelties, we studied the development of symbiotic organs in five stinkbug species representing the superfamily Lygaeoidea in which diverse bacteriocyte/bacteriome systems have evolved. We tracked the symbiont movement within the eggs during the embryonic development and determined crucial stages at which symbiont infection and bacteriocyte formation occur, using whole-mount fluorescence in situ hybridization. In summary, three distinct developmental patterns were observed: two different modes of symbiont transfer from initial symbiont cluster (symbiont ball) to presumptive bacteriocytes in the embryonic abdomen, and direct incorporation of the symbiont ball without translocation of bacterial cells. Across the host taxa, only closely related species seemed to have evolved relatively conserved types of bacteriome development, suggesting repeated evolution of host symbiotic cells and organs from multiple independent origins.
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Affiliation(s)
- Stefan Martin Kuechler
- Department of Animal Ecology II, University of Bayreuth, Bayreuth, Germany.,Tropical Biosphere Research Center, University of the Ryukyus, Okinawa, Japan
| | - Takema Fukatsu
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | - Yu Matsuura
- Tropical Biosphere Research Center, University of the Ryukyus, Okinawa, Japan
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Lee J, Kim CH, Jang HA, Kim JK, Kotaki T, Shinoda T, Shinada T, Yoo JW, Lee BL. Burkholderia gut symbiont modulates titer of specific juvenile hormone in the bean bug Riptortus pedestris. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2019; 99:103399. [PMID: 31195052 DOI: 10.1016/j.dci.2019.103399] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 05/17/2019] [Accepted: 05/17/2019] [Indexed: 06/09/2023]
Abstract
Recent studies have provided molecular evidence that gut symbiotic bacteria modulate host insect development, fitness and reproduction. However, the molecular mechanisms through which gut symbionts regulate these aspects of host physiology remain elusive. To address these questions, we prepared two different Riptortus-Burkholderia insect models, Burkholderia gut symbiont-colonized (Sym) Riptortus pedestris insects and gut symbiont-noncolonized (Apo) insects. Upon LC-MS analyses, juvenile hormone III skipped bisepoxide (JHSB3) was newly identified from Riptortus Apo- and Sym-female and male adults' insect hemolymph and JHSB3 titer in the Apo- and Sym-female insects were measured because JH is important for regulating reproduction in adult insects. The JHSB3 titer in the Sym-females were consistently higher compared to those of Apo-females. Since previous studies reported that Riptortus hexamerin-α and vitellogenin proteins were upregulated by the topical abdominal application of a JH-analog, chemically synthesized JHSB3 was administered to Apo-females. As expected, the hexamerin-α and vitellogenin proteins were dramatically increased in the hemolymph of JHSB3-treated Apo-females, resulting in increased egg production compared to that in Sym-females. Taken together, these results demonstrate that colonization of Burkholderia gut symbiont in the host insect stimulates biosynthesis of the heteroptera-specific JHSB3, leading to larger number of eggs produced and enhanced fitness in Riptortus host insects.
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Affiliation(s)
- Junbeom Lee
- Global Research Laboratory, College of Pharmacy, Pusan National University, Busan, 46241, South Korea
| | - Chan-Hee Kim
- Global Research Laboratory, College of Pharmacy, Pusan National University, Busan, 46241, South Korea
| | - Ho Am Jang
- Global Research Laboratory, College of Pharmacy, Pusan National University, Busan, 46241, South Korea
| | - Jiyeun Kate Kim
- Department of Microbiology, College of Medicine, Kosin University, Busan, 49267, South Korea
| | - Toyomi Kotaki
- National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, 305-8634, Japan
| | - Tetsuro Shinoda
- Faculty of Food and Agricultural Sciences Fukushima University, 1 Kanayagawa, Fukushima, 960-1248, Japan
| | - Tetsuro Shinada
- (e)Graduate School of Science, Osaka City University, Osaka, 558-8585, Japan
| | - Jin-Wook Yoo
- Global Research Laboratory, College of Pharmacy, Pusan National University, Busan, 46241, South Korea
| | - Bok Luel Lee
- Global Research Laboratory, College of Pharmacy, Pusan National University, Busan, 46241, South Korea.
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45
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Garcia JR, Larsen TJ, Queller DC, Strassmann JE. Fitness costs and benefits vary for two facultative Burkholderia symbionts of the social amoeba, Dictyostelium discoideum. Ecol Evol 2019; 9:9878-9890. [PMID: 31534701 PMCID: PMC6745654 DOI: 10.1002/ece3.5529] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 06/19/2019] [Accepted: 07/02/2019] [Indexed: 12/18/2022] Open
Abstract
Hosts and their associated microbes can enter into different relationships, which can range from mutualism, where both partners benefit, to exploitation, where one partner benefits at the expense of the other. Many host-microbe relationships have been presumed to be mutualistic, but frequently only benefits to the host, and not the microbial symbiont, have been considered. Here, we address this issue by looking at the effect of host association on the fitness of two facultative members of the Dictyostelium discoideum microbiome (Burkholderia agricolaris and Burkholderia hayleyella). Using two indicators of bacterial fitness, growth rate and abundance, we determined the effect of D. discoideum on Burkholderia fitness. In liquid culture, we found that D. discoideum amoebas lowered the growth rate of both Burkholderia species. In soil microcosms, we tracked the abundance of Burkholderia grown with and without D. discoideum over a month and found that B. hayleyella had larger populations when associating with D. discoideum while B. agricolaris was not significantly affected. Overall, we find that both B. agricolaris and B. hayleyella pay a cost to associate with D. discoideum, but B. hayleyella can also benefit under some conditions. Understanding how fitness varies in facultative symbionts will help us understand the persistence of host-symbiont relationships. OPEN RESEARCH BADGES This article has earned an Open Data Badge for making publicly available the digitally-shareable data necessary to reproduce the reported results. The data is available at https://openscholarship.wustl.edu/data/15/.
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Affiliation(s)
- Justine R. Garcia
- Department of BiologyWashington University in St. LouisSt. LouisMOUSA
- Present address:
Department of BiologyNew Mexico Highlands UniversityLas VegasNMUSA
| | - Tyler J. Larsen
- Department of BiologyWashington University in St. LouisSt. LouisMOUSA
| | - David C. Queller
- Department of BiologyWashington University in St. LouisSt. LouisMOUSA
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Koch EJ, McFall-Ngai M. Model systems for the study of how symbiotic associations between animals and extracellular bacterial partners are established and maintained. DRUG DISCOVERY TODAY. DISEASE MODELS 2019; 28:3-12. [PMID: 32855643 PMCID: PMC7449258 DOI: 10.1016/j.ddmod.2019.08.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
This contribution describes the current state of experimental model development and use as a strategy for gaining insight into the form and function of certain types of host-microbe associations. Development of quality models for the study of symbiotic systems will be critical not only to facilitate an understanding of mechanisms underlying symbiosis, but also for providing insights into how drug development can promote healthy animal-microbe interactions as well as the treatment of pathogenic infections. Because of the growing awareness over the last decade of the importance of symbiosis in biology, a number of model systems has emerged to examine how these partnerships are maintained within and across generations of the host. The focus here will be upon host-bacterial symbiotic systems that, as in humans, (i) are acquired from the environment each generation, or horizontally transmitted, and (ii) are defined by interactions at the interface of their cellular boundaries, i.e., extracellular symbiotic associations. As with the use of models in other fields of biology where complexity is daunting (e.g., developmental biology or brain circuitry), each model has its strengths and weaknesses, i.e., no one model system will provide easy access to all the questions defining what is conserved in cell-cell interactions in symbiosis and what creates diversity within such partnerships. Rather, as discussed here, the more models explored, the richer our understanding of these associations is likely to be.
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Affiliation(s)
- Eric J. Koch
- Kewalo Marine Laboratory, University of Hawaiʻi at Mānoa, 41 Ahui Street, Honolulu, Hawaii 96813 USA
| | - Margaret McFall-Ngai
- Kewalo Marine Laboratory, University of Hawaiʻi at Mānoa, 41 Ahui Street, Honolulu, Hawaii 96813 USA
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47
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Moran NA, Ochman H, Hammer TJ. Evolutionary and ecological consequences of gut microbial communities. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2019; 50:451-475. [PMID: 32733173 DOI: 10.1146/annurev-ecolsys-110617-062453] [Citation(s) in RCA: 121] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Animals are distinguished by having guts: organs that must extract nutrients from food while barring invasion by pathogens. Most guts are colonized by non-pathogenic microorganisms, but the functions of these microbes, or even the reasons why they occur in the gut, vary widely among animals. Sometimes these microorganisms have co-diversified with hosts; sometimes they live mostly elsewhere in the environment. Either way, gut microorganisms often benefit hosts. Benefits may reflect evolutionary "addiction" whereby hosts incorporate gut microorganisms into normal developmental processes. But benefits often include novel ecological capabilities; for example, many metazoan clades exist by virtue of gut communities enabling new dietary niches. Animals vary immensely in their dependence on gut microorganisms, from lacking them entirely, to using them as food, to obligate dependence for development, nutrition, or protection. Many consequences of gut microorganisms for hosts can be ascribed to microbial community processes and the host's ability to shape these processes.
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Affiliation(s)
- Nancy A Moran
- Department of Integrative Biology, University of Texas at Austin, Austin, TX 78703 USA
| | - Howard Ochman
- Department of Integrative Biology, University of Texas at Austin, Austin, TX 78703 USA
| | - Tobin J Hammer
- Department of Integrative Biology, University of Texas at Austin, Austin, TX 78703 USA
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48
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Gilbert SF. Developmental symbiosis facilitates the multiple origins of herbivory. Evol Dev 2019; 22:154-164. [PMID: 31332951 DOI: 10.1111/ede.12291] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 02/22/2019] [Accepted: 02/28/2019] [Indexed: 01/05/2023]
Abstract
Developmental bias toward particular evolutionary trajectories can be facilitated through symbiosis. Organisms are holobionts, consisting of zygote-derived cells and a consortia of microbes, and the development, physiology, and immunity of animals are properties of complex interactions between the zygote-derived cells and microbial symbionts. Such symbionts can be agents of developmental plasticity, allowing an organism to develop in particular directions. This plasticity can lead to genetic assimilation either through the incorporation of microbial genes into host genomes or through the direct maternal transmission of the microbes. Such plasticity can lead to niche construction, enabling the microbes to remodel host anatomy and/or physiology. In this article, I will focus on the ability of symbionts to bias development toward the evolution of herbivory. I will posit that the behavioral and morphological manifestations of herbivorous phenotypes must be preceded by the successful establishment of a community of symbiotic microbes that can digest cell walls and detoxify plant poisons. The ability of holobionts to digest plant materials can range from being a plastic trait, dependent on the transient incorporation of environmental microbes, to becoming a heritable trait of the holobiont organism, transmitted through the maternal propagation of symbionts or their genes.
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Affiliation(s)
- Scott F Gilbert
- Department of Biology, Swarthmore College, Swarthmore, Pennsylvania
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Mergaert P. Role of antimicrobial peptides in controlling symbiotic bacterial populations. Nat Prod Rep 2019; 35:336-356. [PMID: 29393944 DOI: 10.1039/c7np00056a] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Covering: up to 2018 Antimicrobial peptides (AMPs) have been known for well over three decades as crucial mediators of the innate immune response in animals and plants, where they are involved in the killing of infecting microbes. However, AMPs have now also been found to be produced by eukaryotic hosts during symbiotic interactions with bacteria. These symbiotic AMPs target the symbionts and therefore have a more subtle biological role: not eliminating the microbial symbiont population but rather keeping it in check. The arsenal of AMPs and the symbionts' adaptations to resist them are in a careful balance, which contributes to the establishment of the host-microbe homeostasis. Although in many cases the biological roles of symbiotic AMPs remain elusive, for a number of symbiotic interactions, precise functions have been assigned or proposed to the AMPs, which are discussed here. The microbiota living on epithelia in animals, from the most primitive ones to the mammals, are challenged by a cocktail of AMPs that determine the specific composition of the bacterial community as well as its spatial organization. In the symbiosis of legume plants with nitrogen-fixing rhizobium bacteria, the host deploys an extremely large panel of AMPs - called nodule-specific cysteine-rich (NCR) peptides - that drive the bacteria into a terminally differentiated state and manipulate the symbiont physiology to maximize the benefit for the host. The NCR peptides are used as tools to enslave the bacterial symbionts, limiting their reproduction but keeping them metabolically active for nitrogen fixation. In the nutritional symbiotic interactions of insects and protists that have vertically transmitted bacterial symbionts with reduced genomes, symbiotic AMPs could facilitate the integration of the endosymbiont and host metabolism by favouring the flow of metabolites across the symbiont membrane through membrane permeabilization.
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Affiliation(s)
- P Mergaert
- Institute for Integrative Biology of the Cell, UMR9198, CNRS, Université Paris-Sud, CEA, Avenue de la Terrasse, 91198 Gif-sur-Yvette, France.
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diCenzo GC, Mengoni A, Perrin E. Chromids Aid Genome Expansion and Functional Diversification in the Family Burkholderiaceae. Mol Biol Evol 2019; 36:562-574. [PMID: 30608550 DOI: 10.1093/molbev/msy248] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Multipartite genomes, containing at least two large replicons, are found in diverse bacteria; however, the advantage of this genome structure remains incompletely understood. Here, we perform comparative genomics of hundreds of finished β-proteobacterial genomes to gain insights into the role and emergence of multipartite genomes. Almost all essential secondary replicons (chromids) of the β-proteobacteria are found in the family Burkholderiaceae. These replicons arose from just two plasmid acquisition events, and they were likely stabilized early in their evolution by the presence of core genes. On average, Burkholderiaceae genera with multipartite genomes had a larger total genome size, but smaller chromosome, than genera without secondary replicons. Pangenome-level functional enrichment analyses suggested that interreplicon functional biases are partially driven by the enrichment of secondary replicons in the accessory pangenome fraction. Nevertheless, the small overlap in orthologous groups present in each replicon's pangenome indicated a clear functional separation of the replicons. Chromids appeared biased to environmental adaptation, as the functional categories enriched on chromids were also overrepresented on the chromosomes of the environmental genera (Paraburkholderia and Cupriavidus) compared with the pathogenic genera (Burkholderia and Ralstonia). Using ancestral state reconstruction, it was predicted that the rate of accumulation of modern-day genes by chromids was more rapid than the rate of gene accumulation by the chromosomes. Overall, the data are consistent with a model where the primary advantage of secondary replicons is in facilitating increased rates of gene acquisition through horizontal gene transfer, consequently resulting in replicons enriched in genes associated with adaptation to novel environments.
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Affiliation(s)
- George C diCenzo
- Department of Biology, University of Florence, Sesto Fiorentino, Florence, Italy
| | - Alessio Mengoni
- Department of Biology, University of Florence, Sesto Fiorentino, Florence, Italy
| | - Elena Perrin
- Department of Biology, University of Florence, Sesto Fiorentino, Florence, Italy
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