1
|
Blanton AG, Perkins S, Peterson BF. In vitro assays reveal inherently insecticide-tolerant termite symbionts. Front Physiol 2023; 14:1134936. [PMID: 37501931 PMCID: PMC10368989 DOI: 10.3389/fphys.2023.1134936] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Accepted: 06/30/2023] [Indexed: 07/29/2023] Open
Abstract
Introduction: Termite symbionts are well known for conferring a myriad of benefits to their hosts. Bacterial symbionts are repeatedly associated with increased fitness, nutritional supplementation, pathogen protection, and proper development across insect taxa. In addition, several recent studies link bacterial symbionts to reduced insecticide efficacy. This has important implications both in pest control management and environmental bioremediation efforts. Insects' guts may be a valuable resource for microbes with broad application given their unique niches and metabolic diversity. Though insecticide resistance in termites is considered unlikely due to their life history, the close association of termites with a multitude of bacteria raises the question: is there potential for symbiont-mediated pesticide tolerance in termites? Methods and results: We identified a candidate that could grow in minimal medium containing formulated pesticide. This bacterial isolate was then subjected to continuous culture and subsequently demonstrated improved performance in the presence of pesticide. Isolates subjected to continuous culture were then grown at a range of concentrations from 1-10X the formulation rate. After constant exposure for several generations, isolates grew significantly better. Conclusion: Here we demonstrate that naïve insect hosts can harbor symbionts with inherent insecticide tolerance capable of rapid adaptation to increasing insecticide concentrations overtime. This has broad implications for both pest control and environmental cleanup of residual pesticides.
Collapse
|
2
|
Bulmer MS, Franco BA, Biswas A, Greenbaum SF. Overcoming Immune Deficiency with Allogrooming. INSECTS 2023; 14:insects14020128. [PMID: 36835697 PMCID: PMC9965724 DOI: 10.3390/insects14020128] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/20/2023] [Accepted: 01/23/2023] [Indexed: 05/13/2023]
Abstract
Allogrooming appears to be essential in many social animals for protection from routine exposure to parasites. In social insects, it appears to be critical for the removal of pathogenic propagules from the cuticle before they can start an infectious cycle. For subterranean termites, this includes fungal spores commonly encountered in the soil, such as Metarhizium conidia, that can quickly germinate and penetrate the cuticle. We investigated whether there is a difference in reliance on social and innate immunity in two closely related subterranean termites for protection from fatal infections by two locally encountered Metarhizium species. Our results indicate that relatively weak innate immunity in one termite species is compensated by more sustained allogrooming. This includes enhanced allogrooming in response to concentrations of conidia that reflect more routine contamination of the cuticle as well as to heavy cuticular contamination that elicits a networked emergency response.
Collapse
|
3
|
Tang YL, Kong YH, Qin S, Merchant A, Shi JZ, Zhou XG, Li MW, Wang Q. Transcriptomic dissection of termite gut microbiota following entomopathogenic fungal infection. Front Physiol 2023; 14:1194370. [PMID: 37153226 PMCID: PMC10161392 DOI: 10.3389/fphys.2023.1194370] [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: 03/27/2023] [Accepted: 04/14/2023] [Indexed: 05/09/2023] Open
Abstract
Termites are social insects that live in the soil or in decaying wood, where exposure to pathogens should be common. However, these pathogens rarely cause mortality in established colonies. In addition to social immunity, the gut symbionts of termites are expected to assist in protecting their hosts, though the specific contributions are unclear. In this study, we examined this hypothesis in Odontotermes formosanus, a fungus-growing termite in the family Termitidae, by 1) disrupting its gut microbiota with the antibiotic kanamycin, 2) challenging O. formosanus with the entomopathogenic fungus Metarhizium robertsii, and finally 3) sequencing the resultant gut transcriptomes. As a result, 142531 transcripts and 73608 unigenes were obtained, and unigenes were annotated following NR, NT, KO, Swiss-Prot, PFAM, GO, and KOG databases. Among them, a total of 3,814 differentially expressed genes (DEGs) were identified between M. robertsii infected termites with or without antibiotics treatment. Given the lack of annotated genes in O. formosanus transcriptomes, we examined the expression profiles of the top 20 most significantly differentially expressed genes using qRT-PCR. Several of these genes, including APOA2, Calpain-5, and Hsp70, were downregulated in termites exposed to both antibiotics and pathogen but upregulated in those exposed only to the pathogen, suggesting that gut microbiota might buffer/facilitate their hosts against infection by finetuning physiological and biochemical processes, including innate immunity, protein folding, and ATP synthesis. Overall, our combined results imply that stabilization of gut microbiota can assist termites in maintaining physiological and biochemical homeostasis when foreign pathogenic fungi invade.
Collapse
Affiliation(s)
- Ya-ling Tang
- Jiangsu Key Laboratory of Sericultural Biology and Biotechnology, School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu Province, China
- Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, China
| | - Yun-hui Kong
- Jiangsu Key Laboratory of Sericultural Biology and Biotechnology, School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu Province, China
| | - Sheng Qin
- Jiangsu Key Laboratory of Sericultural Biology and Biotechnology, School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu Province, China
- Key Laboratory of Silkworm and Mulberry Genetic Improvement, Ministry of Agriculture and Rural Affairs, Sericultural Research Institute, Chinese Academy of Agricultural Science, Zhenjiang, Jiangsu Province, China
| | - Austin Merchant
- Department of Entomology, University of Kentucky, Lexington, KY, United States
| | - Ji-zhe Shi
- Department of Entomology, University of Kentucky, Lexington, KY, United States
| | - Xu-guo Zhou
- Department of Entomology, University of Kentucky, Lexington, KY, United States
- *Correspondence: Xu-guo Zhou, ; Mu-wang Li, ; Qian Wang,
| | - Mu-wang Li
- Jiangsu Key Laboratory of Sericultural Biology and Biotechnology, School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu Province, China
- Key Laboratory of Silkworm and Mulberry Genetic Improvement, Ministry of Agriculture and Rural Affairs, Sericultural Research Institute, Chinese Academy of Agricultural Science, Zhenjiang, Jiangsu Province, China
- *Correspondence: Xu-guo Zhou, ; Mu-wang Li, ; Qian Wang,
| | - Qian Wang
- Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, China
- *Correspondence: Xu-guo Zhou, ; Mu-wang Li, ; Qian Wang,
| |
Collapse
|
4
|
Choudhary M, Kumar V, Naik B, Verma A, Saris PEJ, Kumar V, Gupta S. Antifungal metabolites, their novel sources, and targets to combat drug resistance. Front Microbiol 2022; 13:1061603. [PMID: 36532457 PMCID: PMC9755354 DOI: 10.3389/fmicb.2022.1061603] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 11/08/2022] [Indexed: 09/29/2023] Open
Abstract
Excessive antibiotic prescriptions as well as their misuse in agriculture are the main causes of antimicrobial resistance which poses a growing threat to public health. It necessitates the search for novel chemicals to combat drug resistance. Since ancient times, naturally occurring medicines have been employed and the enormous variety of bioactive chemicals found in nature has long served as an inspiration for researchers looking for possible therapeutics. Secondary metabolites from microorganisms, particularly those from actinomycetes, have made it incredibly easy to find new molecules. Different actinomycetes species account for more than 70% of naturally generated antibiotics currently used in medicine, and they also produce a variety of secondary metabolites, including pigments, enzymes, and anti-inflammatory compounds. They continue to be a crucial source of fresh chemical diversity and a crucial component of drug discovery. This review summarizes some uncommon sources of antifungal metabolites and highlights the importance of further research on these unusual habitats as a source of novel antimicrobial molecules.
Collapse
Affiliation(s)
- Megha Choudhary
- Himalayan School of Biosciences, Swami Rama Himalayan University, Dehradun, India
| | - Vijay Kumar
- Himalayan School of Biosciences, Swami Rama Himalayan University, Dehradun, India
| | - Bindu Naik
- Department of Life Sciences (Food Technology & Nutrition), Graphic Era (Deemed to be University), Dehradun, India
| | - Ankit Verma
- Himalayan School of Biosciences, Swami Rama Himalayan University, Dehradun, India
| | - Per Erik Joakim Saris
- Department of Microbiology, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
| | - Vivek Kumar
- Himalayan School of Biosciences, Swami Rama Himalayan University, Dehradun, India
| | - Sanjay Gupta
- Himalayan School of Biosciences, Swami Rama Himalayan University, Dehradun, India
| |
Collapse
|
5
|
Ashbrook AR, Mikaelyan A, Schal C. Comparative Efficacy of a Fungal Entomopathogen with a Broad Host Range against Two Human-Associated Pests. INSECTS 2022; 13:insects13090774. [PMID: 36135475 PMCID: PMC9505452 DOI: 10.3390/insects13090774] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 08/16/2022] [Accepted: 08/18/2022] [Indexed: 05/03/2023]
Abstract
The ability of a fungal entomopathogen to infect an insect depends on a variety of factors, including strain, host, and environmental conditions. Similarly, an insect’s ability to prevent fungal infection is dependent on its biology, environment, and evolutionary history. Synanthropic pests have adapted to thrive in the indoor environment, yet they arose from divergent evolutionary lineages and occupy different feeding guilds. The hematophagous bed bug (Cimex lectularius) and omnivorous German cockroach (Blattella germanica) are highly successful indoors, but have evolved different physiological and behavioral adaptations to cope with the human-built environment, some of which also reduce the efficacy of fungal biopesticides. In order to gain greater insight into the host barriers that prevent or constrain fungal infection in bed bugs and German cockroaches, we tested different doses of Beauveria bassiana GHA through surface contact, topical application, feeding, and injection. Bed bugs were generally more susceptible to infection by B. bassiana with the mode of delivery having a significant impact on infectivity. The German cockroach was highly resilient to infection, requiring high doses of fungal conidia (>8.8 × 104) delivered by injection into the hemocoel to cause mortality. Mortality occurred much faster in both insect species after exposure to surfaces dusted with dry conidia than surfaces treated with conidia suspended in water or oil. These findings highlight the importance of developing innovative delivery techniques to enhance fungal entomopathogens against bed bugs and cockroaches.
Collapse
|
6
|
Eason J, Mason L. Characterization of Microbial Communities from the Alimentary Canal of Typhaea stercorea (L.) (Coleoptera: Mycetophagidae). INSECTS 2022; 13:insects13080685. [PMID: 36005310 PMCID: PMC9408915 DOI: 10.3390/insects13080685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 07/18/2022] [Accepted: 07/24/2022] [Indexed: 12/10/2022]
Abstract
Simple Summary Hairy fungus beetle, Typhaea stercorea, is a secondary post-harvest pest of stored grains that thrives by feeding on mytoxigenic fungi. Bacterial communities residing in the alimentary canal of most insects contribute to their host’s development. While there are many examples, little is known about the role of bacterial communities in the alimentary canal of T. stercorea. The objectives of this study were to (1) characterize the microbial communities residing in T. stercorea and (2) compare the microbial compositions of field-collected and laboratory-reared populations. In this study, we were able to identify bacterial communities that possess mycolytic properties and track mark changes in the microbiota profiles associated with development. The genus Pseudomonas was enriched in T. stercorea larvae compared to adults. Furthermore, field-collected T. sterocrea adults had a lower species richness than both larva and adult laboratory-reared T. sterocrea. Moreover, the gut microbial compositions of field-collected and laboratory-reared populations were vastly different. Overall, our results suggest that the environment and physiology can shift the microbial composition in the alimentary canal of T. stercorea. Abstract The gut microbiomes of symbiotic insects typically mediate essential functions lacking in their hosts. Here, we describe the composition of microbes residing in the alimentary canal of the hairy fungus beetle, Typhaea stercorea (L.), at various life stages. This beetle is a post-harvest pest of stored grains that feeds on fungi and serves as a vector of mycotoxigenic fungi. It has been reported that the bacterial communities found in most insects’ alimentary canals contribute to nutrition, immune defenses, and protection from pathogens. Hence, bacterial symbionts may play a key role in the digestive system of T. stercorea. Using 16S rRNA amplicon sequencing, we examined the microbiota of T. stercorea. We found no difference in bacterial species richness between larvae and adults, but there were compositional differences across life stages (PERMANOVA:pseudo-F(8,2) = 8.22; p = 0.026). The three most abundant bacteria found in the alimentary canal of the larvae and adults included Pseudomonas (47.67% and 0.21%, respectively), an unspecified genus of the Enterobacteriaceae family (46.60 % and 90.97%, respectively), and Enterobacter (3.89% and 5.75%, respectively). Furthermore, Pseudomonas spp. are the predominant bacteria in the larval stage. Our data indicated that field-collected T. stercorea tended to have lower species richness than laboratory-reared beetles (Shannon: H = 5.72; p = 0.057). Furthermore, the microbial communities of laboratory-reared insects resembled one another, whereas field-collected adults exhibited variability (PERMANOVA:pseudo-F(10,3) = 4.41; p = 0.006). We provide evidence that the environment and physiology can shift the microbial composition in the alimentary canal of T. stercorea.
Collapse
|
7
|
Rosengaus R, Traniello J, Bakker T. Sociality and disease: behavioral perspectives in ecological and evolutionary immunology. Behav Ecol Sociobiol 2022; 76:98. [PMID: 35821673 PMCID: PMC9263030 DOI: 10.1007/s00265-022-03203-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- Rebeca Rosengaus
- Department of Marine and Environmental Sciences, Northeastern University, Boston, MA 02115-5000 USA
| | - James Traniello
- Department of Biology, Boston University, 5 Cummington Mall, Boston, MA 02215 USA
| | - Theo Bakker
- Institute for Evolutionary Biology and Ecology, University of Bonn, An der Immenburg 1, 53121 Bonn, Germany
| |
Collapse
|
8
|
Intersection between parental investment, transgenerational immunity, and termite sociality in the face of disease: a theoretical approach. Behav Ecol Sociobiol 2022. [DOI: 10.1007/s00265-022-03128-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
|
9
|
Bulmer MS, Stefano AM. Termite eusociality and contrasting selective pressure on social and innate immunity. Behav Ecol Sociobiol 2021. [DOI: 10.1007/s00265-021-03090-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
10
|
Wu CY, Meng J, Merchant A, Zhang YX, Li MW, Zhou XG, Wang Q. Microbial Response to Fungal Infection in a Fungus-Growing Termite, Odontotermes formosanus (Shiraki). Front Microbiol 2021; 12:723508. [PMID: 34880836 PMCID: PMC8645866 DOI: 10.3389/fmicb.2021.723508] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 11/01/2021] [Indexed: 12/12/2022] Open
Abstract
The crosstalk between gut microbiota and host immunity has emerged as one of the research foci of microbiome studies in recent years. The purpose of this study was to determine how gut microbes respond to fungal infection in termites, given their reliance on gut symbionts for food intake as well as maintaining host health. Here, we used Metarhizium robertsii, an entomopathogenic fungus, to infect Odontotermes formosanus, a fungus-growing termite in the family Termitidae, and documented changes in host gut microbiota via a combination of bacterial 16S rDNA sequencing, metagenomic shotgun sequencing, and transmission electron microscopy. Our analyses found that when challenged with Metarhizium, the termite gut showed reduced microbial diversity within the first 12 h of fungal infection and then recovered and even surpassed pre-infection flora levels. These combined results shed light on the role of gut flora in maintaining homeostasis and immune homeostasis in the host, and the impact of gut flora dysbiosis on host susceptibility to infection.
Collapse
Affiliation(s)
- Chen-Yu Wu
- Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, China.,School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, China
| | - Jing Meng
- Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, China
| | - Austin Merchant
- Department of Entomology, University of Kentucky, Lexington, KY, United States
| | - Yi-Xiang Zhang
- CAS Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, China.,CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| | - Mu-Wang Li
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, China
| | - Xu-Guo Zhou
- Department of Entomology, University of Kentucky, Lexington, KY, United States
| | - Qian Wang
- Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, China
| |
Collapse
|
11
|
Cole ME, Ceja-Navarro JA, Mikaelyan A. The power of poop: Defecation behaviors and social hygiene in insects. PLoS Pathog 2021; 17:e1009964. [PMID: 34710195 PMCID: PMC8553070 DOI: 10.1371/journal.ppat.1009964] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Marissa E. Cole
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, North Carolina, United States of America
| | - Javier A. Ceja-Navarro
- Joint BioEnergy Institute, Emeryville, California, United States of America
- Bioengineering and Biomedical Sciences Department, Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America
- Institute for Biodiversity Science and Sustainability, California Academy of Sciences, San Francisco, California, United States of America
| | - Aram Mikaelyan
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, North Carolina, United States of America
- * E-mail:
| |
Collapse
|
12
|
Scharf ME, Peterson BF. A Century of Synergy in Termite Symbiosis Research: Linking the Past with New Genomic Insights. ANNUAL REVIEW OF ENTOMOLOGY 2021; 66:23-43. [PMID: 33417825 DOI: 10.1146/annurev-ento-022420-074746] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Termites have long been studied for their symbiotic associations with gut microbes. In the late nineteenth century, this relationship was poorly understood and captured the interest of parasitologists such as Joseph Leidy; this research led to that of twentieth-century biologists and entomologists including Cleveland, Hungate, Trager, and Lüscher. Early insights came via microscopy, organismal, and defaunation studies, which led to descriptions of microbes present, descriptions of the roles of symbionts in lignocellulose digestion, and early insights into energy gas utilization by the host termite. Focus then progressed to culture-dependent microbiology and biochemical studies of host-symbiont complementarity, which revealed specific microhabitat requirements for symbionts and noncellulosic mechanisms of symbiosis (e.g., N2 fixation). Today, knowledge on termite symbiosis has accrued exponentially thanks to omic technologies that reveal symbiont identities, functions, and interdependence, as well as intricacies of host-symbiont complementarity. Moving forward, the merging of classical twentieth-century approaches with evolving omic tools should provide even deeper insights into host-symbiont interplay.
Collapse
Affiliation(s)
- Michael E Scharf
- Department of Entomology, Purdue University, West Lafayette, Indiana 47907, USA;
| | - Brittany F Peterson
- Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, Illinois 62026, USA;
| |
Collapse
|
13
|
Nishimura Y, Otagiri M, Yuki M, Shimizu M, Inoue JI, Moriya S, Ohkuma M. Division of functional roles for termite gut protists revealed by single-cell transcriptomes. THE ISME JOURNAL 2020; 14:2449-2460. [PMID: 32514117 PMCID: PMC7490689 DOI: 10.1038/s41396-020-0698-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 05/20/2020] [Accepted: 05/29/2020] [Indexed: 11/08/2022]
Abstract
The microbiome in the hindgut of wood-feeding termites comprises various species of bacteria, archaea, and protists. This gut community is indispensable for the termite, which thrives solely on recalcitrant and nitrogen-poor wood. However, the difficulty in culturing these microorganisms has hindered our understanding of the function of each species in the gut. Although protists predominate in the termite gut microbiome and play a major role in wood digestion, very few culture-independent studies have explored the contribution of each species to digestion. Here, we report single-cell transcriptomes of four protists species comprising the protist population in worldwide pest Coptotermes formosanus. Comparative transcriptomic analysis revealed that the expression patterns of the genes involved in wood digestion were different among species, reinforcing their division of roles in wood degradation. Transcriptomes, together with enzyme assays, also suggested that one of the protists, Cononympha leidyi, actively degrades chitin and assimilates it into amino acids. We propose that C. leidyi contributes to nitrogen recycling and inhibiting infection from entomopathogenic fungi through chitin degradation. Two of the genes for chitin degradation were further revealed to be acquired via lateral gene transfer (LGT) implying the importance of LGT in the evolution of symbiosis. Our single-cell-based approach successfully characterized the function of each protist in termite hindgut and explained why the gut community includes multiple species.
Collapse
Affiliation(s)
- Yuki Nishimura
- Microbe Division, RIKEN BioResource Research Center, Tsukuba, Japan.
| | - Masato Otagiri
- Photonics Control Technology Team, RIKEN Center for Advanced Photonics, Wako, Japan
| | - Masahiro Yuki
- Microbe Division, RIKEN BioResource Research Center, Tsukuba, Japan
| | - Michiru Shimizu
- Microbe Division, RIKEN BioResource Research Center, Tsukuba, Japan
| | - Jun-Ichi Inoue
- Microbe Division, RIKEN BioResource Research Center, Tsukuba, Japan
| | - Shigeharu Moriya
- Environmental Metabolic Analysis Research Team, RIKEN Center for Sustainable Resource Science, Ykohama, Japan
| | - Moriya Ohkuma
- Microbe Division, RIKEN BioResource Research Center, Tsukuba, Japan
| |
Collapse
|
14
|
Zhao X, Liu L, Zhou W, Cai Q, Huang Q. Roles of selenoprotein T and transglutaminase in active immunization against entomopathogenic fungi in the termite Reticulitermes chinensis. JOURNAL OF INSECT PHYSIOLOGY 2020; 125:104085. [PMID: 32634432 DOI: 10.1016/j.jinsphys.2020.104085] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Revised: 06/15/2020] [Accepted: 06/16/2020] [Indexed: 06/11/2023]
Abstract
Active immunization can protect individuals from infectious diseases in social insects. It is well established that trace elements are essential to the host immune system, but the related gene functions in insect social immunity are unknown. Here, we found that the levels of three free elements (Se, Ca and Cr) and selenoprotein T (SELT) expression were significantly decreased in the termite Reticulitermes chinensis Snyder during active immunization against the entomopathogenic fungus Metarhizium anisopliae (Metchnikoff) Sorokin. Thus, we further explored the role of the SELT gene in the active immunization of termites. After SELT was significantly silenced by RNAi, the nestmates of fungus-contaminated termites exhibited reduced antifungal activity and increased mortality, along with increased expression of the immune genes transglutaminase (TG) and transferrin (Tsf), indicating that the active immunization of termites was disrupted by SELT silencing. Moreover, the TG-knockdown nestmates of fungus-contaminated termites significantly decreased grooming behavior, antifungal activity and survival, despite the upregulation of SELT expression, also suggesting that the active immunization of termites was disrupted by the silencing of TG. These findings demonstrated that both SELT gene and TG gene play important roles in driving active immunization against the entomopathogenic fungus M. anisopliae in R. chinensis.
Collapse
Affiliation(s)
- Xingying Zhao
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Long Liu
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Wei Zhou
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Qing Cai
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Qiuying Huang
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, Huazhong Agricultural University, Wuhan 430070, Hubei, China.
| |
Collapse
|
15
|
Cole EL, Bayne H, Rosengaus RB. Young but not defenceless: antifungal activity during embryonic development of a social insect. ROYAL SOCIETY OPEN SCIENCE 2020; 7:191418. [PMID: 32968491 PMCID: PMC7481685 DOI: 10.1098/rsos.191418] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 07/27/2020] [Indexed: 05/16/2023]
Abstract
Termites live in environments heavily colonized by diverse microorganisms, including pathogens. Eggs laid within the nest are likely to experience similar pathogenic pressures as those experienced by older nest-mates. Consequently, eggs may be under selective pressures to be immune-competent. Through in vitro experiments using developing embryos of the dampwood termite, Zootermopsis angusticollis, we tested the ontogeny, location and strength of their antifungal activity against the fungus, Metarhizium brunneum. Exterior washes of the chorion (extra-chorionic) and components within the chorion (intra-chorionic) were incubated with fungal conidia, which were then scored for viability. The fungistatic activity was location and developmental stage dependent. Extra-chorionic washes had relatively weak antifungal activity. Intra-chorionic homogenates were highly antifungal, exhibiting increased potency through development. The positive correlation between intra-chorionic fungistasis and developmental stage is probably due to the expression of endogenous proteins during embryogenesis. Boiling of both the extra-chorionic washes and the intra-chorionic contents rescued conidia viability, indicating the antifungal agent(s) is (are) heat-sensitive and probably proteinaceous. This study is the first to address embryonic antifungal activity in a hemimetabolous, eusocial taxon. Our results support the hypothesis that microbes have been significant agents of selection in termites, fostering the evolution of antifungal properties even in the most immature stage of development.
Collapse
|
16
|
Li J, Cao C, Jiang Y, Huang Q, Shen Y, Ni J. A Novel Digestive GH16 β-1,3(4)-Glucanase from the Fungus-Growing Termite Macrotermes barneyi. Appl Biochem Biotechnol 2020; 192:1284-1297. [PMID: 32725373 DOI: 10.1007/s12010-020-03368-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 06/22/2020] [Indexed: 01/22/2023]
Abstract
β-1,3-glucanases are the main digestive enzymes of plant and fungal cell wall. Transcriptomic analysis of the fungus-growing termite Macrotermes barneyi revealed a high expression of a predicted β-1,3(4)-glucanase (Mbbgl) transcript in termite gut. Here, we described the cDNA cloning, heterologous expression, and enzyme characterization of Mbbgl. Sequence analysis and RT-PCR results showed that Mbbgl is a termite-origin GH16 β-1,3(4)-glucanase. The recombinant enzyme showed the highest activity towards laminarin and was active optimally at 50 °C, pH 5.5. The enzyme displayed endo/exo β-1,3(4)-glucanase activities. Moreover, Mbbgl had weak transglycosylation activity. The results indicate that Mbbgl is an endogenous digestive β-1,3(4)-glucanase, which contributes to the decomposition of plant biomass and fungal hyphae. Additionally, the multiple activities, pH, and ion stabilities make Mbbgl a potential candidate for application in the food industry.
Collapse
Affiliation(s)
- Jingjing Li
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Qingdao, 266237, China
| | - Chunjing Cao
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Qingdao, 266237, China.,Biotechnology Development Institute, Qilu Pharmaceutical Co. Ltd., Jinan, 250100, China
| | - Yutong Jiang
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Qingdao, 266237, China
| | - Qihong Huang
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Qingdao, 266237, China
| | - Yulong Shen
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Qingdao, 266237, China.
| | - Jinfeng Ni
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Qingdao, 266237, China.
| |
Collapse
|
17
|
Esparza-Mora MA, Davis HE, Meconcelli S, Plarre R, McMahon DP. Inhibition of a Secreted Immune Molecule Interferes With Termite Social Immunity. Front Ecol Evol 2020. [DOI: 10.3389/fevo.2020.00075] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
18
|
Kloc M, Uosef A, Elshawwaf M, Abdelshafy AAA, Elsaid KMK, Kubiak JZ, Ghobrial RM. The Macrophages and Intestinal Symbiosis. Results Probl Cell Differ 2020; 69:605-616. [PMID: 33263889 DOI: 10.1007/978-3-030-51849-3_23] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The human intestinal tract is inhabited by trillions of microorganisms and houses the largest pool of macrophages in the human body. Being a part of the innate immune system, the macrophages, the professional phagocytes, vigorously respond to the microbial and dietary antigens present in the intestine. Because such a robust immune response poses the danger to the survival of the non-harmful and beneficial gut microbiota, the macrophages developed mechanisms of recognition and hyposensitivity toward the non-harmful/beneficial inhabitants of the gut. We will discuss the evolution and identity of some of these mechanisms in the following chapter.
Collapse
Affiliation(s)
- Malgorzata Kloc
- The Houston Methodist Research Institute, Houston, TX, USA. .,Department of Surgery, Houston Methodist Hospital, Houston, TX, USA. .,Department of Genetics, The University of Texas, M.D. Anderson Cancer Center, Houston, TX, USA.
| | - Ahmed Uosef
- The Houston Methodist Research Institute, Houston, TX, USA.,Department of Surgery, Houston Methodist Hospital, Houston, TX, USA
| | - Mahmoud Elshawwaf
- The Houston Methodist Research Institute, Houston, TX, USA.,Department of Surgery, Houston Methodist Hospital, Houston, TX, USA
| | - Ahmed Adel Abbas Abdelshafy
- The Houston Methodist Research Institute, Houston, TX, USA.,Department of Surgery, Houston Methodist Hospital, Houston, TX, USA.,Department of General Surgery, Faculty of Medicine, Ain-Shams University, Cairo, Egypt
| | - Kamal Mamdoh Kamal Elsaid
- The Houston Methodist Research Institute, Houston, TX, USA.,Department of Surgery, Houston Methodist Hospital, Houston, TX, USA.,Department of General Surgery, Faculty of Medicine, Ain-Shams University, Cairo, Egypt
| | - Jacek Z Kubiak
- Department of Regenerative Medicine and Cell Biology, Military Institute of Hygiene and Epidemiology (WIHE), Warszawa, Poland.,Faculty of Medicine, Cell Cycle Group, Institute of Genetics and Development of Rennes, (IGDR) UnivRennes, CNRS, UMR 6290, Rennes, France
| | - Rafik Mark Ghobrial
- The Houston Methodist Research Institute, Houston, TX, USA.,Department of Surgery, Houston Methodist Hospital, Houston, TX, USA
| |
Collapse
|
19
|
Hu H, da Costa RR, Pilgaard B, Schiøtt M, Lange L, Poulsen M. Fungiculture in Termites Is Associated with a Mycolytic Gut Bacterial Community. mSphere 2019; 4:e00165-19. [PMID: 31092601 PMCID: PMC6520439 DOI: 10.1128/msphere.00165-19] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 04/09/2019] [Indexed: 11/20/2022] Open
Abstract
Termites forage on a range of substrates, and it has been suggested that diet shapes the composition and function of termite gut bacterial communities. Through comparative analyses of gut metagenomes in nine termite species with distinct diets, we characterize bacterial community compositions and use peptide-based functional annotation method to determine biomass-degrading enzymes and the bacterial taxa that encode them. We find that fungus-growing termite guts have relatively more fungal cell wall-degrading enzyme genes, while wood-feeding termite gut communities have relatively more plant cell wall-degrading enzyme genes. Interestingly, wood-feeding termite gut bacterial genes code for abundant chitinolytic enzymes, suggesting that fungal biomass within the decaying wood likely contributes to gut bacterial or termite host nutrition. Across diets, the dominant biomass-degrading enzymes are predominantly coded for by the most abundant bacterial taxa, suggesting tight links between diet and gut community composition, with the most marked difference being the communities coding for the mycolytic capacity of the fungus-growing termite gut.IMPORTANCE Understanding functional capacities of gut microbiomes is important to improve our understanding of symbiotic associations. Here, we use peptide-based functional annotation to show that the gut microbiomes of fungus-farming termites code for a wealth of enzymes that likely target the fungal diet the termites eat. Comparisons to other termites showed that fungus-growing termite guts have relatively more fungal cell wall-degrading enzyme genes, whereas wood-feeding termite gut communities have relatively more plant cell wall-degrading enzyme genes. Across termites with different diets, the dominant biomass-degrading enzymes are predominantly coded for by the most abundant bacterial taxa, suggesting tight links between diet and gut community compositions.
Collapse
Affiliation(s)
- Haofu Hu
- Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Rafael Rodrigues da Costa
- Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Bo Pilgaard
- Department of Bioengineering, Technical University of Denmark, Lyngby, Denmark
| | - Morten Schiøtt
- Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Lene Lange
- Department of Bioengineering, Technical University of Denmark, Lyngby, Denmark
| | - Michael Poulsen
- Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| |
Collapse
|
20
|
Martin JS, Bulmer MS. A Lab-Based Study of Temperate Forest Termite Impacts on Two Common Wood-Rot Fungi. ENVIRONMENTAL ENTOMOLOGY 2018; 47:1388-1393. [PMID: 30192929 DOI: 10.1093/ee/nvy122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Indexed: 06/08/2023]
Abstract
Termites and fungi are the primary decomposers of dead wood. Interactions between wood-feeding termites and wood-rot fungi are inevitable given their shared food source. Termites have developed multiple defense strategies against infectious fungi, such as Metarhizium spp., that include antifungal proteins in their saliva and fungal inhibition properties in their gut. The antifungal properties of termite salivary secretions depend on β-1,3-glucanases that are likely to be effective against a broad spectrum of filamentous fungi. Given the overlap in niches, there is opportunity for interference competition between termites and wood-rot fungi to occur. Here we demonstrate that β-1,3-glucanases in the saliva and the antifungal properties of the gut of the eastern subterranean termite Reticulitermes flavipes (Kollar) (Blattodea: Rhinotermitidae) affects the growth of two common wood-rot fungi, Gloeophyllum trabeum Persoon (Murrill) (Gloeophyllales: Gloeophyllaceae) and Phanerochaete chrysosporium (Burdsall) (Polyporales: Phanerochaetaceae).
Collapse
Affiliation(s)
- Jason S Martin
- Department of Biological Sciences, Towson University, Towson, MD
| | - Mark S Bulmer
- Department of Biological Sciences, Towson University, Towson, MD
| |
Collapse
|
21
|
He S, Johnston PR, Kuropka B, Lokatis S, Weise C, Plarre R, Kunte HJ, McMahon DP. Termite soldiers contribute to social immunity by synthesizing potent oral secretions. INSECT MOLECULAR BIOLOGY 2018; 27:564-576. [PMID: 29663551 DOI: 10.1111/imb.12499] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The importance of soldiers to termite society defence has long been recognized, but the contribution of soldiers to other societal functions, such as colony immunity, is less well understood. We explore this issue by examining the role of soldiers in protecting nestmates against pathogen infection. Even though they are unable to engage in grooming behaviour, we find that the presence of soldiers of the Darwin termite, Mastotermes darwiniensis, significantly improves the survival of nestmates following entomopathogenic infection. We also show that the copious exocrine oral secretions produced by Darwin termite soldiers contain a high concentration of proteins involved in digestion, chemical biosynthesis, and immunity. The oral secretions produced by soldiers are sufficient to protect nestmates against infection, and they have potent inhibitory activity against a broad spectrum of microbes. Our findings support the view that soldiers may play an important role in colony immunity, and broaden our understanding of the possible function of soldiers during the origin of soldier-first societies.
Collapse
Affiliation(s)
- S He
- Institute of Biology, Freie Universität Berlin, Berlin, Germany
- Department for Materials and Environment, BAM Federal Institute for Materials Research and Testing, Berlin, Germany
| | - P R Johnston
- Institute of Biology, Freie Universität Berlin, Berlin, Germany
- Berlin Center for Genomics in Biodiversity Research, Berlin, Germany
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Berlin, Germany
| | - B Kuropka
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
| | - S Lokatis
- Institute of Biology, Freie Universität Berlin, Berlin, Germany
- Department for Materials and Environment, BAM Federal Institute for Materials Research and Testing, Berlin, Germany
| | - C Weise
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
| | - R Plarre
- Department for Materials and Environment, BAM Federal Institute for Materials Research and Testing, Berlin, Germany
| | - H-J Kunte
- Department for Materials and Environment, BAM Federal Institute for Materials Research and Testing, Berlin, Germany
| | - D P McMahon
- Institute of Biology, Freie Universität Berlin, Berlin, Germany
- Department for Materials and Environment, BAM Federal Institute for Materials Research and Testing, Berlin, Germany
| |
Collapse
|
22
|
Sun Q, Haynes KF, Zhou X. Managing the risks and rewards of death in eusocial insects. Philos Trans R Soc Lond B Biol Sci 2018; 373:20170258. [PMID: 30012744 PMCID: PMC6053982 DOI: 10.1098/rstb.2017.0258] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/03/2018] [Indexed: 12/22/2022] Open
Abstract
Eusocial insects frequently face death of colony members as a consequence of living in large groups where the success of the colony is not dependent on the fate of the individual. Whereas death of conspecifics commonly triggers aversion in many group-living species due to risk of pathogens, eusocial insects perform cooperative corpse management. The causes and social context of the death, as well as feeding and nesting ecology of the species, influence the way that corpses are treated. The corpse itself releases cues that dictate the colony's response. As a result, social insects exhibit behavioural responses that promote disease resistance, colony defence and nutrient recycling. Corpse management represents a unique adaption that enhances colony success, and is another factor that has enabled eusocial insects to be so successful. In this review, we summarize the causes of death, the sensory detection of death and corpse management strategies of social insects. In addition, we provide insights into the evolution of behavioural response to the dead and the ecological relevance of corpse management.This article is part of the theme issue 'Evolutionary thanatology: impacts of the dead on the living in humans and other animals'.
Collapse
Affiliation(s)
- Qian Sun
- Department of Entomology, Louisiana State University, Baton Rouge, LA 70803, USA
- Department of Entomology, University of Kentucky, S-225 Agricultural Science Centre North, Lexington, KY 40546, USA
| | - Kenneth F Haynes
- Department of Entomology, University of Kentucky, S-225 Agricultural Science Centre North, Lexington, KY 40546, USA
| | - Xuguo Zhou
- Department of Entomology, University of Kentucky, S-225 Agricultural Science Centre North, Lexington, KY 40546, USA
| |
Collapse
|
23
|
Inagaki T, Matsuura K. Extended mutualism between termites and gut microbes: nutritional symbionts contribute to nest hygiene. Naturwissenschaften 2018; 105:52. [DOI: 10.1007/s00114-018-1580-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 08/14/2018] [Accepted: 08/14/2018] [Indexed: 01/16/2023]
|
24
|
Onchuru TO, Javier Martinez A, Ingham CS, Kaltenpoth M. Transmission of mutualistic bacteria in social and gregarious insects. CURRENT OPINION IN INSECT SCIENCE 2018; 28:50-58. [PMID: 30551767 DOI: 10.1016/j.cois.2018.05.002] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 04/30/2018] [Accepted: 05/08/2018] [Indexed: 05/09/2023]
Abstract
Symbiotic microbes can confer a range of benefits to social, sub-social, and gregarious insects that include contributions to nutrition, digestion, and defense. Transmission of beneficial symbionts to the next generation in these insects sometimes occurs transovarially as in many solitary insects, but primarily through social contact such as coprophagy in gregarious taxa, and trophallaxis in eusocial insects. While these behaviors benefit reliable transmission of multi-microbial assemblages, they may also come at the cost of inviting the spread of parasites and pathogens. Nonetheless, the overall benefit of social symbiont transmission may be one of several important factors that reinforce the evolution of social behaviors and insect eusociality.
Collapse
Affiliation(s)
- Thomas Ogao Onchuru
- Department of Evolutionary Ecology, Institute of Organismic and Molecular Evolution, Johannes Gutenberg-University Mainz, Johann-Joachim-Becher-Weg 13, 55128 Mainz, Germany
| | - Adam Javier Martinez
- Department of Evolutionary Ecology, Institute of Organismic and Molecular Evolution, Johannes Gutenberg-University Mainz, Johann-Joachim-Becher-Weg 13, 55128 Mainz, Germany
| | - Chantal Selina Ingham
- Department of Evolutionary Ecology, Institute of Organismic and Molecular Evolution, Johannes Gutenberg-University Mainz, Johann-Joachim-Becher-Weg 13, 55128 Mainz, Germany
| | - Martin Kaltenpoth
- Department of Evolutionary Ecology, Institute of Organismic and Molecular Evolution, Johannes Gutenberg-University Mainz, Johann-Joachim-Becher-Weg 13, 55128 Mainz, Germany.
| |
Collapse
|
25
|
Rao XJ, Zhan MY, Pan YM, Liu S, Yang PJ, Yang LL, Yu XQ. Immune functions of insect βGRPs and their potential application. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2018; 83:80-88. [PMID: 29229443 DOI: 10.1016/j.dci.2017.12.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 12/06/2017] [Accepted: 12/08/2017] [Indexed: 06/07/2023]
Abstract
Insects rely completely on the innate immune system to sense the foreign bodies and to mount the immune responses. Germ-line encoded pattern recognition receptors play crucial roles in recognizing pathogen-associated molecular patterns. Among them, β-1,3-glucan recognition proteins (βGRPs) and gram-negative bacteria-binding proteins (GNBPs) belong to the same pattern recognition receptor family, which can recognize β-1,3-glucans. Typical insect βGRPs are comprised of a tandem carbohydrate-binding module in the N-terminal and a glucanase-like domain in the C-terminal. The former can recognize triple-helical β-1,3-glucans, whereas the latter, which normally lacks the enzymatic activity, can recruit adapter proteins to initiate the protease cascade. According to studies, insect βGRPs possess at least three types of functions. Firstly, some βGRPs cooperate with peptidoglycan recognition proteins to recognize the lysine-type peptidoglycans upstream of the Toll pathway. Secondly, some directly recognize fungal β-1,3-glucans to activate the Toll pathway and melanization. Thirdly, some form the 'attack complexes' with other immune effectors to promote the antifungal defenses. The current review will focus on the discovery of insect βGRPs, functions of some well-characterized members, structure-function studies and their potential application.
Collapse
Affiliation(s)
- Xiang-Jun Rao
- School of Plant Protection, Anhui Agricultural University, Hefei, Anhui 230036, China.
| | - Ming-Yue Zhan
- School of Plant Protection, Anhui Agricultural University, Hefei, Anhui 230036, China
| | - Yue-Min Pan
- School of Plant Protection, Anhui Agricultural University, Hefei, Anhui 230036, China
| | - Su Liu
- School of Plant Protection, Anhui Agricultural University, Hefei, Anhui 230036, China
| | - Pei-Jin Yang
- School of Plant Protection, Anhui Agricultural University, Hefei, Anhui 230036, China
| | - Li-Ling Yang
- School of Plant Protection, Anhui Agricultural University, Hefei, Anhui 230036, China
| | - Xiao-Qiang Yu
- Institute of Insect Science and Technology & School of Life Sciences, South China Normal University, Guangzhou 510631, China
| |
Collapse
|
26
|
Boucias DG, Zhou Y, Huang S, Keyhani NO. Microbiota in insect fungal pathology. Appl Microbiol Biotechnol 2018; 102:5873-5888. [PMID: 29802479 DOI: 10.1007/s00253-018-9089-z] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 05/10/2018] [Accepted: 05/10/2018] [Indexed: 12/17/2022]
Abstract
Significant progress has been made in the biochemical and genetic characterization of the host-pathogen interaction mediated by insect pathogenic fungi, with the most widely studied being the Ascomycetes (Hypocrealean) fungi, Metarhizium robertsii and Beauveria bassiana. However, few studies have examined the consequences and effects of host (insect) microbes, whether compatible or antagonistic, on the development and survival of entomopathogenic fungi. Host microbes can act on the insect cuticular surface, within the gut, in specialized insect microbe hosting structures, and within cells, and they include a wide array of facultative and/or obligate exosymbionts and endosymbionts. The insect microbiome differs across developmental stages and in response to nutrition (e.g., different plant hosts for herbivores) and environmental conditions, including exposure to chemical insecticides. Here, we review recent advances indicating that insect-pathogenic fungi have evolved a spectrum of strategies for exploiting or suppressing host microbes, including the production of antimicrobial compounds that are expressed at discrete stages of the infection process. Conversely, there is increasing evidence that some insects have acquired microbes that may be specialized in the production of antifungal compounds to combat infection by (entomopathogenic) fungi. Consideration of the insect microbiome in fungal insect pathology represents a new frontier that can help explain previously obscure ecological and pathological aspects of the biology of entomopathogenic fungi. Such information may lead to novel approaches to improving the efficacy of these organisms in pest control efforts.
Collapse
Affiliation(s)
- Drion G Boucias
- Entomology and Nematology Department, University of Florida, Gainesville, FL, 32611, USA
| | - Yonghong Zhou
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL, 32611, USA
| | - Shuaishuai Huang
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL, 32611, USA
| | - Nemat O Keyhani
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL, 32611, USA.
| |
Collapse
|
27
|
Pull CD, Ugelvig LV, Wiesenhofer F, Grasse AV, Tragust S, Schmitt T, Brown MJF, Cremer S. Destructive disinfection of infected brood prevents systemic disease spread in ant colonies. eLife 2018; 7:e32073. [PMID: 29310753 PMCID: PMC5760203 DOI: 10.7554/elife.32073] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2017] [Accepted: 11/17/2017] [Indexed: 01/19/2023] Open
Abstract
In social groups, infections have the potential to spread rapidly and cause disease outbreaks. Here, we show that in a social insect, the ant Lasius neglectus, the negative consequences of fungal infections (Metarhizium brunneum) can be mitigated by employing an efficient multicomponent behaviour, termed destructive disinfection, which prevents further spread of the disease through the colony. Ants specifically target infected pupae during the pathogen's non-contagious incubation period, utilising chemical 'sickness cues' emitted by pupae. They then remove the pupal cocoon, perforate its cuticle and administer antimicrobial poison, which enters the body and prevents pathogen replication from the inside out. Like the immune system of a metazoan body that specifically targets and eliminates infected cells, ants destroy infected brood to stop the pathogen completing its lifecycle, thus protecting the rest of the colony. Hence, in an analogous fashion, the same principles of disease defence apply at different levels of biological organisation.
Collapse
Affiliation(s)
- Christopher D Pull
- IST Austria (Institute of Science and Technology Austria)KlosterneuburgAustria
| | - Line V Ugelvig
- IST Austria (Institute of Science and Technology Austria)KlosterneuburgAustria
| | - Florian Wiesenhofer
- IST Austria (Institute of Science and Technology Austria)KlosterneuburgAustria
| | - Anna V Grasse
- IST Austria (Institute of Science and Technology Austria)KlosterneuburgAustria
| | - Simon Tragust
- IST Austria (Institute of Science and Technology Austria)KlosterneuburgAustria
- Evolution, Genetics and BehaviourUniversity of RegensburgRegensburgGermany
| | - Thomas Schmitt
- Department of Animal Ecology and Tropical BiologyUniversity of WürzburgWürzburgGermany
| | - Mark JF Brown
- School of Biological SciencesRoyal Holloway University of LondonEghamUnited Kingdom
| | - Sylvia Cremer
- IST Austria (Institute of Science and Technology Austria)KlosterneuburgAustria
| |
Collapse
|
28
|
Peterson BF, Scharf ME. Metatranscriptome analysis reveals bacterial symbiont contributions to lower termite physiology and potential immune functions. BMC Genomics 2016; 17:772. [PMID: 27716053 PMCID: PMC5045658 DOI: 10.1186/s12864-016-3126-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2016] [Accepted: 09/26/2016] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND Symbioses throughout the animal kingdom are known to extend physiological and ecological capabilities to hosts. Insect-microbe associations are extremely common and are often related to novel niche exploitation, fitness advantages, and even speciation events. These phenomena include expansions in host diet, detoxification of insecticides and toxins, and increased defense against pathogens. However, dissecting the contributions of individual groups of symbionts at the molecular level is often underexplored due to methodological and analytical limitations. Termites are one of the best studied systems for physiological collaborations between host and symbiota; however, most work in lower termites (those with bacterial and protist symbionts) focuses on the eukaryotic members of this symbiotic consortium. Here we present a metatranscriptomic analysis which provides novel insights into bacterial contributions to the holobiont of the eastern subterranean termite, Reticulitermes flavipes, in the presence and absence of a fungal pathogen. RESULTS Using a customized ribodepletion strategy, a metatranscriptome assembly was obtained representing the host termite as well as bacterial and protist symbiota. Sequence data provide new insights into biosynthesis, catabolism, and transport of major organic molecules and ions by the gut consortium, and corroborate previous findings suggesting that bacteria play direct roles in nitrogen fixation, amino acid biosynthesis, and lignocellulose digestion. With regard to fungal pathogen challenge, a total of 563 differentially expressed candidate host and symbiont contigs were identified (162 up- and 401 downregulated; α/FDR = 0.05) including an upregulated bacterial amidohydrolase. CONCLUSIONS This study presents the most complete bacterial metatranscriptome from a lower termite and provides a framework on which to build a more complete model of termite-symbiont interactions including, but not limited to, digestion and pathogen defense.
Collapse
Affiliation(s)
- Brittany F Peterson
- Department of Entomology, Purdue University, 901 W. State St, West Lafayette, IN, 47907-2089, USA. .,Present address: Center for Insect Science, University of Arizona, 1007 E. Lowell St, Tucson, AZ, 85721, USA.
| | - Michael E Scharf
- Department of Entomology, Purdue University, 901 W. State St, West Lafayette, IN, 47907-2089, USA
| |
Collapse
|
29
|
Zeng Y, Hu XP, Suh SJ. Characterization of Antibacterial Activities of Eastern Subterranean Termite, Reticulitermes flavipes, against Human Pathogens. PLoS One 2016; 11:e0162249. [PMID: 27611223 PMCID: PMC5017719 DOI: 10.1371/journal.pone.0162249] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 08/21/2016] [Indexed: 11/18/2022] Open
Abstract
The emergence and dissemination of multidrug resistant bacterial pathogens necessitate research to find new antimicrobials against these organisms. We investigated antimicrobial production by eastern subterranean termites, Reticulitermes flavipes, against a panel of bacteria including three multidrug resistant (MDR) and four non-MDR human pathogens. We determined that the crude extract of naïve termites had a broad-spectrum activity against the non-MDR bacteria but it was ineffective against the three MDR pathogens Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus (MRSA), and Acinetobacter baumannii. Heat or trypsin treatment resulted in a complete loss of activity suggesting that antibacterial activity was proteinaceous in nature. The antimicrobial activity changed dramatically when the termites were fed with either heat-killed P. aeruginosa or MRSA. Heat-killed P. aeruginosa induced activity against P. aeruginosa and MRSA while maintaining or slightly increasing activity against non-MDR bacteria. Heat-killed MRSA induced activity specifically against MRSA, altered the activity against two other Gram-positive bacteria, and inhibited activity against three Gram-negative bacteria. Neither the naïve termites nor the termites challenged with heat-killed pathogens produced antibacterial activity against A. baumannii. Further investigation demonstrated that hemolymph, not the hindgut, was the primary source of antibiotic activity. This suggests that the termite produces these antibacterial activities and not the hindgut microbiota. Two-dimensional gel electrophoretic analyses of 493 hemolymph protein spots indicated that a total of 38 and 65 proteins were differentially expressed at least 2.5-fold upon being fed with P. aeruginosa and MRSA, respectively. Our results provide the first evidence of constitutive and inducible activities produced by R. flavipes against human bacterial pathogens.
Collapse
Affiliation(s)
- Yuan Zeng
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL, United States of America
| | - Xing Ping Hu
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL, United States of America
- * E-mail: (SS); (XPH)
| | - Sang-Jin Suh
- Department of Biological Sciences, Auburn University, Auburn University, Auburn, AL, United States of America
- * E-mail: (SS); (XPH)
| |
Collapse
|
30
|
|
31
|
Armitage SAO, Fernández-Marín H, Boomsma JJ, Wcislo WT. Slowing them down will make them lose: a role for attine ant crop fungus in defending pupae against infections? J Anim Ecol 2016; 85:1210-21. [PMID: 27136600 PMCID: PMC6084299 DOI: 10.1111/1365-2656.12543] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 04/12/2016] [Indexed: 02/05/2023]
Abstract
Fungus-growing ants (Attini) have evolved an obligate dependency upon a basidiomycete fungus that they cultivate as their food. Less well known is that the crop fungus is also used by many attine species to cover their eggs, larvae and pupae. The adaptive functional significance of this brood covering is poorly understood. One hypothesis to account for this behaviour is that it is part of the pathogen protection portfolio when many thousands of sister workers live in close proximity and larvae and pupae are not protected by cells, as in bees and wasps, and are immobile. We performed behavioural observations on brood covering in the leaf-cutting ant Acromyrmex echinatior, and we experimentally manipulated mycelial cover on pupae and exposed them to the entomopathogenic fungus Metarhizium brunneum to test for a role in pathogen resistance. Our results show that active mycelial brood covering by workers is a behaviourally plastic trait that varies temporally, and across life stages and castes. The presence of a fungal cover on the pupae reduced the rate at which conidia appeared and the percentage of pupal surface that produced pathogen spores, compared to pupae that had fungal cover experimentally removed or naturally had no mycelial cover. Infected pupae with mycelium had higher survival rates than infected pupae without the cover, although this depended upon the time at which adult sister workers were allowed to interact with pupae. Finally, workers employed higher rates of metapleural gland grooming to infected pupae without mycelium than to infected pupae with mycelium. Our results imply that mycelial brood covering may play a significant role in suppressing the growth and subsequent spread of disease, thus adding a novel layer of protection to their defence portfolio.
Collapse
Affiliation(s)
- Sophie A O Armitage
- Department of Biology, Centre for Social Evolution, University of Copenhagen, Universitetsparken 15, 2100, Copenhagen, Denmark
| | - Hermógenes Fernández-Marín
- Department of Biology, Centre for Social Evolution, University of Copenhagen, Universitetsparken 15, 2100, Copenhagen, Denmark.,Instituto de Investigaciones Científicas y Servicios de Alta Tecnología, Edificio 219, Ciudad del Saber, Clayton, Panamá City, Panamá,Smithsonian Tropical Research Institute, Apartado 0843-03092, Balboa, Ancón, Panamá
| | - Jacobus J Boomsma
- Department of Biology, Centre for Social Evolution, University of Copenhagen, Universitetsparken 15, 2100, Copenhagen, Denmark
| | - William T Wcislo
- Smithsonian Tropical Research Institute, Apartado 0843-03092, Balboa, Ancón, Panamá
| |
Collapse
|
32
|
Ford SA, King KC. Harnessing the Power of Defensive Microbes: Evolutionary Implications in Nature and Disease Control. PLoS Pathog 2016; 12:e1005465. [PMID: 27058881 PMCID: PMC4826280 DOI: 10.1371/journal.ppat.1005465] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Affiliation(s)
- Suzanne A. Ford
- Department of Zoology, University of Oxford, Oxford, United Kingdom
- * E-mail: (SAF); (KCK)
| | - Kayla C. King
- Department of Zoology, University of Oxford, Oxford, United Kingdom
- * E-mail: (SAF); (KCK)
| |
Collapse
|
33
|
Peterson BF, Scharf ME. Lower Termite Associations with Microbes: Synergy, Protection, and Interplay. Front Microbiol 2016; 7:422. [PMID: 27092110 PMCID: PMC4824777 DOI: 10.3389/fmicb.2016.00422] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Accepted: 03/16/2016] [Indexed: 11/15/2022] Open
Abstract
Lower-termites are one of the best studied symbiotic systems in insects. Their ability to feed on a nitrogen-poor, wood-based diet with help from symbiotic microbes has been under investigation for almost a century. A unique microbial consortium living in the guts of lower termites is essential for wood-feeding. Host and symbiont cellulolytic enzymes synergize each other in the termite gut to increase digestive efficiency. Because of their critical role in digestion, gut microbiota are driving forces in all aspects of termite biology. Social living also comes with risks for termites. The combination of group living and a microbe-rich habitat makes termites potentially vulnerable to pathogenic infections. However, the use of entomopathogens for termite control has been largely unsuccessful. One mechanism for this failure may be symbiotic collaboration; i.e., one of the very reasons termites have thrived in the first place. Symbiont contributions are thought to neutralize fungal spores as they pass through the termite gut. Also, when the symbiont community is disrupted pathogen susceptibility increases. These recent discoveries have shed light on novel interactions for symbiotic microbes both within the termite host and with pathogenic invaders. Lower termite biology is therefore tightly linked to symbiotic associations and their resulting physiological collaborations.
Collapse
Affiliation(s)
| | - Michael E Scharf
- Department of Entomology, Purdue University, West Lafayette IN, USA
| |
Collapse
|
34
|
Brune A, Dietrich C. The Gut Microbiota of Termites: Digesting the Diversity in the Light of Ecology and Evolution. Annu Rev Microbiol 2015. [DOI: 10.1146/annurev-micro-092412-155715] [Citation(s) in RCA: 231] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Andreas Brune
- Department of Biogeochemistry, Max Planck Institute for Terrestrial Microbiology, 35043 Marburg, Germany; ,
| | - Carsten Dietrich
- Department of Biogeochemistry, Max Planck Institute for Terrestrial Microbiology, 35043 Marburg, Germany; ,
| |
Collapse
|
35
|
Liu L, Li G, Sun P, Lei C, Huang Q. Experimental verification and molecular basis of active immunization against fungal pathogens in termites. Sci Rep 2015; 5:15106. [PMID: 26458743 PMCID: PMC4602225 DOI: 10.1038/srep15106] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Accepted: 09/15/2015] [Indexed: 01/30/2023] Open
Abstract
Termites are constantly exposed to many pathogens when they nest and forage in the field, so they employ various immune strategies to defend against pathogenic infections. Here, we demonstrate that the subterranean termite Reticulitermes chinensis employs active immunization to defend against the entomopathogen Metarhizium anisopliae. Our results showed that allogrooming frequency increased significantly between fungus-treated termites and their nestmates. Through active social contact, previously healthy nestmates only received small numbers of conidia from fungus-treated individuals. These nestmates experienced low-level fungal infections, resulting in low mortality and apparently improved antifungal defences. Moreover, infected nestmates promoted the activity of two antioxidant enzymes (SOD and CAT) and upregulated the expression of three immune genes (phenoloxidase, transferrin, and termicin). We found 20 differentially expressed proteins associated with active immunization in R. chinensis through iTRAQ proteomics, including 12 stress response proteins, six immune signalling proteins, and two immune effector molecules. Subsequently, two significantly upregulated (60S ribosomal protein L23 and isocitrate dehydrogenase) and three significantly downregulated (glutathione S-transferase D1, cuticle protein 19, and ubiquitin conjugating enzyme) candidate immune proteins were validated by MRM assays. These findings suggest that active immunization in termites may be regulated by different immune proteins.
Collapse
Affiliation(s)
- Long Liu
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Ganghua Li
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Pengdong Sun
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Chaoliang Lei
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Qiuying Huang
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| |
Collapse
|
36
|
Theis FJ, Ugelvig LV, Marr C, Cremer S. Opposing effects of allogrooming on disease transmission in ant societies. Philos Trans R Soc Lond B Biol Sci 2015; 370:20140108. [PMID: 25870394 PMCID: PMC4410374 DOI: 10.1098/rstb.2014.0108] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/02/2015] [Indexed: 11/12/2022] Open
Abstract
To prevent epidemics, insect societies have evolved collective disease defences that are highly effective at curing exposed individuals and limiting disease transmission to healthy group members. Grooming is an important sanitary behaviour--either performed towards oneself (self-grooming) or towards others (allogrooming)--to remove infectious agents from the body surface of exposed individuals, but at the risk of disease contraction by the groomer. We use garden ants (Lasius neglectus) and the fungal pathogen Metarhizium as a model system to study how pathogen presence affects self-grooming and allogrooming between exposed and healthy individuals. We develop an epidemiological SIS model to explore how experimentally observed grooming patterns affect disease spread within the colony, thereby providing a direct link between the expression and direction of sanitary behaviours, and their effects on colony-level epidemiology. We find that fungus-exposed ants increase self-grooming, while simultaneously decreasing allogrooming. This behavioural modulation seems universally adaptive and is predicted to contain disease spread in a great variety of host-pathogen systems. In contrast, allogrooming directed towards pathogen-exposed individuals might both increase and decrease disease risk. Our model reveals that the effect of allogrooming depends on the balance between pathogen infectiousness and efficiency of social host defences, which are likely to vary across host-pathogen systems.
Collapse
Affiliation(s)
- Fabian J Theis
- Helmholtz Zentrum München-German Research Center for Environmental Health, Institute of Computational Biology, Ingolstädter Landstrasse 1, Neuherberg 85764, Germany Technische Universität München, Center for Mathematics, Chair of Mathematical Modeling of Biological Systems, Boltzmannstraße 3, Garching 85748, Germany
| | - Line V Ugelvig
- IST Austria (Institute of Science and Technology Austria), Am Campus 1, Klosterneuburg 3400, Austria
| | - Carsten Marr
- Helmholtz Zentrum München-German Research Center for Environmental Health, Institute of Computational Biology, Ingolstädter Landstrasse 1, Neuherberg 85764, Germany
| | - Sylvia Cremer
- IST Austria (Institute of Science and Technology Austria), Am Campus 1, Klosterneuburg 3400, Austria
| |
Collapse
|
37
|
Sen R, Raychoudhury R, Cai Y, Sun Y, Lietze VU, Peterson BF, Scharf ME, Boucias DG. Molecular signatures of nicotinoid-pathogen synergy in the termite gut. PLoS One 2015; 10:e0123391. [PMID: 25837376 PMCID: PMC4383478 DOI: 10.1371/journal.pone.0123391] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Accepted: 02/18/2015] [Indexed: 11/19/2022] Open
Abstract
Previous studies in lower termites revealed unexpected synergies between nicotinoid insecticides and fungal entomopathogens. The present study investigated molecular mechanisms of nicotinoid-pathogen synergy in the lower termite Reticulitermes flavipes, using the nicotinoid, imidacloprid, in combination with fungal and bacterial entomopathogens. Particular focus was placed on metatranscriptome composition and microbial dynamics in the symbiont-rich termite gut, which houses diverse mixes of protists and bacteria. cDNA microarrays containing a mix of host and protist symbiont oligonucleotides were used to simultaneously assess termite and protist gene expression. Five treatments were compared that included single challenges with sublethal doses of fungi (Metharizium anisopliae), bacteria (Serratia marcescens) or imidacloprid, and dual challenges with fungi + imidacloprid or bacteria + imidacloprid. Our findings point towards protist dysbiosis and compromised social behavior, rather than suppression of stereotypical immune defense mechanisms, as the dominant factors underlying nicotinoid-pathogen synergy in termites. Also, greater impacts observed for the fungal pathogen than for the bacterial pathogen suggest that the rich bacterial symbiont community in the R. flavipes gut (>5000 species-level phylotypes) exists in an ecological balance that effectively excludes exogenous bacterial pathogens. These findings significantly advance our understanding of antimicrobial defenses in this important eusocial insect group, as well as provide novel insights into how nicotinoids can exert deleterious effects on social insect colonies.
Collapse
Affiliation(s)
- Ruchira Sen
- Dept. of Entomology, Purdue University, West Lafayette, IN, United States of America
| | - Rhitoban Raychoudhury
- Dept. of Entomology, Purdue University, West Lafayette, IN, United States of America
| | - Yunpeng Cai
- Interdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, FL, United States of America
| | - Yijun Sun
- Interdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, FL, United States of America
| | - Verena-Ulrike Lietze
- Entomology and Nematology Department, University of Florida, Gainesville, FL, United States of America
| | - Brittany F. Peterson
- Dept. of Entomology, Purdue University, West Lafayette, IN, United States of America
| | - Michael E. Scharf
- Dept. of Entomology, Purdue University, West Lafayette, IN, United States of America
| | - Drion G. Boucias
- Entomology and Nematology Department, University of Florida, Gainesville, FL, United States of America
| |
Collapse
|
38
|
Scharf ME. Omic research in termites: an overview and a roadmap. Front Genet 2015; 6:76. [PMID: 25821456 PMCID: PMC4358217 DOI: 10.3389/fgene.2015.00076] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 02/13/2015] [Indexed: 11/13/2022] Open
Abstract
Many recent breakthroughs in our understanding of termite biology have been facilitated by "omics" research. Omic science seeks to collectively catalog, quantify, and characterize pools of biological molecules that translate into structure, function, and life processes of an organism. Biological molecules in this context include genomic DNA, messenger RNA, proteins, and other biochemicals. Other permutations of omics that apply to termites include sociogenomics, which seeks to define social life in molecular terms (e.g., behavior, sociality, physiology, symbiosis, etc.) and digestomics, which seeks to define the collective pool of host and symbiont genes that collaborate to achieve high-efficiency lignocellulose digestion in the termite gut. This review covers a wide spectrum of termite omic studies from the past 15 years. Topics covered include a summary of terminology, the various kinds of omic efforts that have been undertaken, what has been revealed, and to a degree, what the results mean. Although recent omic efforts have contributed to a better understanding of many facets of termite and symbiont biology, and have created important new resources for many species, significant knowledge gaps still remain. Crossing these gaps can best be done by applying new omic resources within multi-dimensional (i.e., functional, translational, and applied) research programs.
Collapse
Affiliation(s)
- Michael E Scharf
- Department of Entomology, Purdue University, West Lafayette, IN USA
| |
Collapse
|