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  1. Article ; Online: A global $$Anopheles\ gambiae$$ A n o p h e l e s g a m b i a e gene co-expression network constructed from hundreds of experimental conditions with missing values

    Junyao Kuang / Nicolas Buchon / Kristin Michel / Caterina Scoglio

    BMC Bioinformatics, Vol 23, Iss 1, Pp 1-

    2022  Volume 27

    Abstract: Abstract Background Gene co-expression networks (GCNs) can be used to determine gene regulation and attribute gene function to biological processes. Different high throughput technologies, including one and two-channel microarrays and RNA-sequencing, ... ...

    Abstract Abstract Background Gene co-expression networks (GCNs) can be used to determine gene regulation and attribute gene function to biological processes. Different high throughput technologies, including one and two-channel microarrays and RNA-sequencing, allow evaluating thousands of gene expression data simultaneously, but these methodologies provide results that cannot be directly compared. Thus, it is complex to analyze co-expression relations between genes, especially when there are missing values arising for experimental reasons. Networks are a helpful tool for studying gene co-expression, where nodes represent genes and edges represent co-expression of pairs of genes. Results In this paper, we establish a method for constructing a gene co-expression network for the Anopheles gambiae transcriptome from 257 unique studies obtained with different methodologies and experimental designs. We introduce the sliding threshold approach to select node pairs with high Pearson correlation coefficients. The resulting network, which we name AgGCN1.0, is robust to random removal of conditions and has similar characteristics to small-world and scale-free networks. Analysis of network sub-graphs revealed that the core is largely comprised of genes that encode components of the mitochondrial respiratory chain and the ribosome, while different communities are enriched for genes involved in distinct biological processes. Conclusion Analysis of the network reveals that both the architecture of the core sub-network and the network communities are based on gene function, supporting the power of the proposed method for GCN construction. Application of network science methodology reveals that the overall network structure is driven to maximize the integration of essential cellular functions, possibly allowing the flexibility to add novel functions.
    Keywords Anopheles gambiae ; Co-expression network ; Missing value ; Correlation ; Computer applications to medicine. Medical informatics ; R858-859.7 ; Biology (General) ; QH301-705.5
    Subject code 612
    Language English
    Publishing date 2022-05-01T00:00:00Z
    Publisher BMC
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: Innate immunity in

    Hixson, Bretta / Chen, Robin / Buchon, Nicolas

    Philosophical transactions of the Royal Society of London. Series B, Biological sciences

    2024  Volume 379, Issue 1901, Page(s) 20230063

    Abstract: Discussions of host-microbe interactions in mosquito vectors are frequently dominated by a focus on the human pathogens they transmit (e.g. ...

    Abstract Discussions of host-microbe interactions in mosquito vectors are frequently dominated by a focus on the human pathogens they transmit (e.g.
    MeSH term(s) Animals ; Humans ; Aedes ; Drosophila melanogaster ; Microbiota ; Bacteria ; Immunity, Innate ; Antimicrobial Peptides
    Chemical Substances Antimicrobial Peptides
    Language English
    Publishing date 2024-03-18
    Publishing country England
    Document type Journal Article ; Review
    ZDB-ID 208382-6
    ISSN 1471-2970 ; 0080-4622 ; 0264-3839 ; 0962-8436
    ISSN (online) 1471-2970
    ISSN 0080-4622 ; 0264-3839 ; 0962-8436
    DOI 10.1098/rstb.2023.0063
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: The transcriptional response in mosquitoes distinguishes between fungi and bacteria but not Gram types.

    Hixson, Bretta / Huot, Louise / Morejon, Bianca / Yang, Xiaowei / Nagy, Peter / Michel, Kristin / Buchon, Nicolas

    BMC genomics

    2024  Volume 25, Issue 1, Page(s) 353

    Abstract: Mosquitoes are prolific vectors of human pathogens, therefore a clear and accurate understanding of the organization of their antimicrobial defenses is crucial for informing the development of transmission control strategies. The canonical infection ... ...

    Abstract Mosquitoes are prolific vectors of human pathogens, therefore a clear and accurate understanding of the organization of their antimicrobial defenses is crucial for informing the development of transmission control strategies. The canonical infection response in insects, as described in the insect model Drosophila melanogaster, is pathogen type-dependent, with distinct stereotypical responses to Gram-negative bacteria and Gram-positive bacteria/fungi mediated by the activation of the Imd and Toll pathways, respectively. To determine whether this pathogen-specific discrimination is shared by mosquitoes, we used RNAseq to capture the genome-wide transcriptional response of Aedes aegypti and Anopheles gambiae (s.l.) to systemic infection with Gram-negative bacteria, Gram-positive bacteria, yeasts, and filamentous fungi, as well as challenge with heat-killed Gram-negative, Gram-positive, and fungal pathogens. From the resulting data, we found that Ae. aegypti and An. gambiae both mount a core response to all categories of infection, and this response is highly conserved between the two species with respect to both function and orthology. When we compared the transcriptomes of mosquitoes infected with different types of bacteria, we observed that the intensity of the transcriptional response was correlated with both the virulence and growth rate of the infecting pathogen. Exhaustive comparisons of the transcriptomes of Gram-negative-challenged versus Gram-positive-challenged mosquitoes yielded no difference in either species. In Ae. aegypti, however, we identified transcriptional signatures specific to bacterial infection and to fungal infection. The bacterial infection response was dominated by the expression of defensins and cecropins, while the fungal infection response included the disproportionate upregulation of an uncharacterized family of glycine-rich proteins. These signatures were also observed in Ae. aegypti challenged with heat-killed bacteria and fungi, indicating that this species can discriminate between molecular patterns that are specific to bacteria and to fungi.
    MeSH term(s) Animals ; Humans ; Drosophila melanogaster ; Mosquito Vectors/genetics ; Aedes/genetics ; Aedes/microbiology ; Bacteria ; Fungi/genetics ; Bacterial Infections ; Mycoses
    Language English
    Publishing date 2024-04-09
    Publishing country England
    Document type Journal Article
    ZDB-ID 2041499-7
    ISSN 1471-2164 ; 1471-2164
    ISSN (online) 1471-2164
    ISSN 1471-2164
    DOI 10.1186/s12864-024-10153-0
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: The midgut epithelium of mosquitoes adjusts cell proliferation and endoreplication to respond to physiological challenges.

    Taracena-Agarwal, M L / Hixson, B / Nandakumar, S / Girard-Mejia, A P / Chen, R Y / Huot, L / Padilla, N / Buchon, N

    BMC biology

    2024  Volume 22, Issue 1, Page(s) 22

    Abstract: Background: Hematophagous mosquitoes transmit many pathogens that cause human diseases. Pathogen acquisition and transmission occur when female mosquitoes blood feed to acquire nutrients for reproduction. The midgut epithelium of mosquitoes serves as ... ...

    Abstract Background: Hematophagous mosquitoes transmit many pathogens that cause human diseases. Pathogen acquisition and transmission occur when female mosquitoes blood feed to acquire nutrients for reproduction. The midgut epithelium of mosquitoes serves as the point of entry for transmissible viruses and parasites.
    Results: We studied midgut epithelial dynamics in five major mosquito vector species by quantifying PH3-positive cells (indicative of mitotic proliferation), the incorporation of nucleotide analogs (indicative of DNA synthesis accompanying proliferation and/or endoreplication), and the ploidy (by flow cytometry) of cell populations in the posterior midgut epithelium of adult females. Our results show that the epithelial dynamics of post-emergence maturation and of mature sugar-fed guts were similar in members of the Aedes, Culex, and Anopheles genera. In the first three days post-emergence, ~ 20% of cells in the posterior midgut region of interest incorporated nucleotide analogs, concurrent with both proliferative activity and a broad shift toward higher ploidy. In mature mosquitoes maintained on sugar, an average of 3.5% of cells in the posterior midgut region of interest incorporated nucleotide analogs from five to eight days post-emergence, with a consistent presence of mitotic cells indicating constant cell turnover. Oral bacterial infection triggered a sharp increase in mitosis and nucleotide analog incorporation, suggesting that the mosquito midgut undergoes accelerated cellular turnover in response to damage. Finally, blood feeding resulted in an increase in cell proliferation, but the nature and intensity of the response varied by mosquito species and by blood source (human, bovine, avian or artificial). In An. gambiae, enterocytes appeared to reenter the cell cycle to increase ploidy after consuming blood from all sources except avian.
    Conclusions: We saw that epithelial proliferation, differentiation, and endoreplication reshape the blood-fed gut to increase ploidy, possibly to facilitate increased metabolic activity. Our results highlight the plasticity of the midgut epithelium in mosquitoes' physiological responses to distinct challenges.
    MeSH term(s) Animals ; Female ; Cattle ; Humans ; Endoreduplication ; Epithelium ; Anopheles ; Aedes ; Cell Proliferation ; Sugars ; Nucleotides
    Chemical Substances Sugars ; Nucleotides
    Language English
    Publishing date 2024-01-29
    Publishing country England
    Document type Journal Article
    ZDB-ID 2133020-7
    ISSN 1741-7007 ; 1741-7007
    ISSN (online) 1741-7007
    ISSN 1741-7007
    DOI 10.1186/s12915-023-01769-x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: A global [Formula: see text] gene co-expression network constructed from hundreds of experimental conditions with missing values.

    Kuang, Junyao / Buchon, Nicolas / Michel, Kristin / Scoglio, Caterina

    BMC bioinformatics

    2022  Volume 23, Issue 1, Page(s) 170

    Abstract: Background: Gene co-expression networks (GCNs) can be used to determine gene regulation and attribute gene function to biological processes. Different high throughput technologies, including one and two-channel microarrays and RNA-sequencing, allow ... ...

    Abstract Background: Gene co-expression networks (GCNs) can be used to determine gene regulation and attribute gene function to biological processes. Different high throughput technologies, including one and two-channel microarrays and RNA-sequencing, allow evaluating thousands of gene expression data simultaneously, but these methodologies provide results that cannot be directly compared. Thus, it is complex to analyze co-expression relations between genes, especially when there are missing values arising for experimental reasons. Networks are a helpful tool for studying gene co-expression, where nodes represent genes and edges represent co-expression of pairs of genes.
    Results: In this paper, we establish a method for constructing a gene co-expression network for the Anopheles gambiae transcriptome from 257 unique studies obtained with different methodologies and experimental designs. We introduce the sliding threshold approach to select node pairs with high Pearson correlation coefficients. The resulting network, which we name AgGCN1.0, is robust to random removal of conditions and has similar characteristics to small-world and scale-free networks. Analysis of network sub-graphs revealed that the core is largely comprised of genes that encode components of the mitochondrial respiratory chain and the ribosome, while different communities are enriched for genes involved in distinct biological processes.
    Conclusion: Analysis of the network reveals that both the architecture of the core sub-network and the network communities are based on gene function, supporting the power of the proposed method for GCN construction. Application of network science methodology reveals that the overall network structure is driven to maximize the integration of essential cellular functions, possibly allowing the flexibility to add novel functions.
    MeSH term(s) Gene Expression Profiling/methods ; Gene Regulatory Networks ; Sequence Analysis, RNA ; Transcriptome
    Language English
    Publishing date 2022-05-09
    Publishing country England
    Document type Journal Article
    ZDB-ID 2041484-5
    ISSN 1471-2105 ; 1471-2105
    ISSN (online) 1471-2105
    ISSN 1471-2105
    DOI 10.1186/s12859-022-04697-9
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Identification of Cellular Genes Involved in Baculovirus GP64 Trafficking to the Plasma Membrane.

    Hodgson, Jeffrey J / Buchon, Nicolas / Blissard, Gary W

    Journal of virology

    2022  Volume 96, Issue 12, Page(s) e0021522

    Abstract: The baculovirus envelope protein GP64 is an essential component of the budded virus and is necessary for efficient virion assembly. Little is known regarding intracellular trafficking of GP64 to the plasma membrane, where it is incorporated into budding ... ...

    Abstract The baculovirus envelope protein GP64 is an essential component of the budded virus and is necessary for efficient virion assembly. Little is known regarding intracellular trafficking of GP64 to the plasma membrane, where it is incorporated into budding virions during egress. To identify host proteins and potential cellular trafficking pathways that are involved in delivery of GP64 to the plasma membrane, we developed and characterized a stable
    MeSH term(s) Animals ; Baculoviridae/metabolism ; Cell Line ; Cell Membrane/virology ; Drosophila melanogaster/virology ; Insect Proteins/genetics ; RNA Interference ; Viral Envelope Proteins/metabolism
    Chemical Substances Insect Proteins ; Viral Envelope Proteins
    Language English
    Publishing date 2022-05-24
    Publishing country United States
    Document type Journal Article ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 80174-4
    ISSN 1098-5514 ; 0022-538X
    ISSN (online) 1098-5514
    ISSN 0022-538X
    DOI 10.1128/jvi.00215-22
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Midgut Epithelial Dynamics Are Central to Mosquitoes' Physiology and Fitness, and to the Transmission of Vector-Borne Disease.

    Hixson, Bretta / Taracena, Mabel Laline / Buchon, Nicolas

    Frontiers in cellular and infection microbiology

    2021  Volume 11, Page(s) 653156

    MeSH term(s) Aedes ; Animals ; Culicidae ; Mosquito Vectors ; Vector Borne Diseases
    Language English
    Publishing date 2021-03-25
    Publishing country Switzerland
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 2619676-1
    ISSN 2235-2988 ; 2235-2988
    ISSN (online) 2235-2988
    ISSN 2235-2988
    DOI 10.3389/fcimb.2021.653156
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Drosophila melanogaster as a powerful tool for studying insect toxicology.

    Scott, Jeffrey G / Buchon, Nicolas

    Pesticide biochemistry and physiology

    2019  Volume 161, Page(s) 95–103

    Abstract: Insecticides are valuable and widely used tools for the control of pest insects. Despite the use of synthetic insecticides for >50 years, we continue to have a limited understanding of the genes that influence the key steps of the poisoning process. ... ...

    Abstract Insecticides are valuable and widely used tools for the control of pest insects. Despite the use of synthetic insecticides for >50 years, we continue to have a limited understanding of the genes that influence the key steps of the poisoning process. Major barriers for improving our understanding of insecticide toxicity have included a narrow range of tools and/or a large number of candidate genes that could be involved in the poisoning process. Herein, we discuss the numerous tools and resources available in Drosophila melanogaster that could be brought to bear to improve our understanding of the processes determining insecticide toxicity. These include unbiased approaches such as forward genetic screens, population genetic methods and candidate gene approaches. Examples are provided to showcase how D. melanogaster has been successfully used for insecticide toxicology studies in the past, and ideas for future studies using this valuable insect are discussed.
    MeSH term(s) Animals ; Drosophila melanogaster/drug effects ; Drosophila melanogaster/genetics ; Genes, Insect ; Insecticides/pharmacokinetics ; Insecticides/toxicity ; Models, Genetic
    Chemical Substances Insecticides
    Language English
    Publishing date 2019-10-21
    Publishing country United States
    Document type Letter
    ZDB-ID 184819-7
    ISSN 1095-9939 ; 0048-3583 ; 0048-3575
    ISSN (online) 1095-9939
    ISSN 0048-3583 ; 0048-3575
    DOI 10.1016/j.pestbp.2019.09.006
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Methods for the study of innate immunity in Drosophila melanogaster.

    Troha, Katia / Buchon, Nicolas

    Wiley interdisciplinary reviews. Developmental biology

    2019  Volume 8, Issue 5, Page(s) e344

    Abstract: From flies to humans, many components of the innate immune system have been conserved during metazoan evolution. This foundational observation has allowed us to develop Drosophila melanogaster, the fruit fly, into a powerful model to study innate ... ...

    Abstract From flies to humans, many components of the innate immune system have been conserved during metazoan evolution. This foundational observation has allowed us to develop Drosophila melanogaster, the fruit fly, into a powerful model to study innate immunity in animals. Thanks to an ever-growing arsenal of genetic tools, an easily manipulated genome, and its winning disposition, Drosophila is now employed to study not only basic molecular mechanisms of pathogen recognition and immune signaling, but also the nature of physiological responses activated in the host by microbial challenge and how dysregulation of these processes contributes to disease. Here, we present a collection of methods and protocols to challenge the fly with an assortment of microbes, both systemically and orally, and assess its humoral, cellular, and epithelial response to infection. Our review covers techniques for measuring the reaction to microbial infection both qualitatively and quantitatively. Specifically, we describe survival, bacterial load, BLUD (a measure of disease tolerance), phagocytosis, melanization, clotting, and ROS production assays, as well as efficient protocols to collect hemolymph and measure immune gene expression. We also offer an updated catalog of online resources and a collection of popular reporter lines and mutants to facilitate research efforts. This article is categorized under: Technologies > Analysis of Cell, Tissue, and Animal Phenotypes.
    MeSH term(s) Animals ; Bacteria/immunology ; Bacteria/pathogenicity ; Bacterial Infections/complications ; Bacterial Infections/immunology ; Bacterial Infections/microbiology ; Drosophila Proteins/metabolism ; Drosophila melanogaster/immunology ; Drosophila melanogaster/metabolism ; Drosophila melanogaster/microbiology ; Immunity, Innate/immunology ; Phagocytosis ; Phenotype ; Signal Transduction
    Chemical Substances Drosophila Proteins
    Language English
    Publishing date 2019-04-16
    Publishing country United States
    Document type Journal Article ; Review
    ISSN 1759-7692
    ISSN (online) 1759-7692
    DOI 10.1002/wdev.344
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: The transcriptional response in mosquitoes distinguishes between fungi and bacteria but not Gram types.

    Hixson, Bretta / Huot, Louise / Morejon, Bianca / Yang, Xiaowei / Nagy, Peter / Michel, Kristin / Buchon, Nicolas

    bioRxiv : the preprint server for biology

    2023  

    Abstract: Mosquitoes are prolific vectors of human pathogens; a clear and accurate understanding of the organization of their antimicrobial defenses is crucial for informing the development of transmission control strategies. The canonical infection response in ... ...

    Abstract Mosquitoes are prolific vectors of human pathogens; a clear and accurate understanding of the organization of their antimicrobial defenses is crucial for informing the development of transmission control strategies. The canonical infection response in insects, as described in the insect model
    Language English
    Publishing date 2023-07-26
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2023.07.26.550663
    Database MEDical Literature Analysis and Retrieval System OnLINE

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