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1.
Virus Res ; 347: 199415, 2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38880334

ABSTRACT

Our study identified strains of the A/H5N1 virus in analyzed samples of subsistence poultry, wild birds, and mammals, belonging to clade 2.3.4.4b, genotype B3.2, with very high genetic similarity to strains from Chile, Uruguay, and Argentina. This suggests a migratory route for wild birds across the Pacific, explaining the phylogenetic relatedness. The Brazilian samples displayed similarity to strains that had already been previously detected in South America. Phylogeographic analysis suggests transmission of US viruses from Europe and Asia, co-circulating with other lineages in the American continent. As mutations can influence virulence and host specificity, genomic surveillance is essential to detect those changes, especially in critical regions, such as hot spots in the HA, NA, and PB2 sequences. Mutations in the PB2 gene (D701N and Q591K) associated with adaptation and transmission in mammals were detected suggesting a potential zoonotic risk. Nonetheless, resistance to neuraminidase inhibitors (NAIs) was not identified, however, continued surveillance is crucial to detect potential resistance. Our study also mapped the spread of the virus in the Southern hemisphere, identifying possible entry routes and highlighting the importance of surveillance to prevent outbreaks and protect both human and animal populations.

2.
Braz J Microbiol ; 2024 Jun 19.
Article in English | MEDLINE | ID: mdl-38898364

ABSTRACT

Bees are fundamental for maintaining pollination-dependent plant populations, both economically and ecologically. In Brazil, they constitute 66.3% of pollinators, contributing to an annual market value estimated at R$ 43 billion for pollination services. Unfortunately, worldwide bee populations are declining due to parasites and pathogens, more specifically viruses, alongside climate change, habitat loss, and pesticides. In this scenario, extensive research concerning bee diversity, virus diversity and surveillance, is necessary to aid the conservation of native managed pollinators and potential wild alternatives besides mitigating the emergence and spread of viral pathogens. A decrease in pollination can be a point of economic vulnerability in a country like Brazil because of its main dependence on food exports. Here we conducted a study aiming to obtain an overview of circulating viruses in bees within Brazilian territory highlighting the need for further studies to have a more realistic view of bee-infecting viruses in Brazil.

3.
Viruses ; 15(12)2023 12 16.
Article in English | MEDLINE | ID: mdl-38140687

ABSTRACT

Parasitoid wasps are fundamental insects for the biological control of agricultural pests. Despite the importance of wasps as natural enemies for more sustainable and healthy agriculture, the factors that could impact their species richness, abundance, and fitness, such as viral diseases, remain almost unexplored. Parasitoid wasps have been studied with regard to the endogenization of viral elements and the transmission of endogenous viral proteins that facilitate parasitism. However, circulating viruses are poorly characterized. Here, RNA viromes of six parasitoid wasp species are studied using public libraries of next-generation sequencing through an integrative bioinformatics pipeline. Our analyses led to the identification of 18 viruses classified into 10 families (Iflaviridae, Endornaviridae, Mitoviridae, Partitiviridae, Virgaviridae, Rhabdoviridae, Chuviridae, Orthomyxoviridae, Xinmoviridae, and Narnaviridae) and into the Bunyavirales order. Of these, 16 elements were described for the first time. We also found a known virus previously identified on a wasp prey which suggests viral transmission between the insects. Altogether, our results highlight the importance of virus surveillance in wasps as its service disruption can affect ecology, agriculture and pest management, impacting the economy and threatening human food security.


Subject(s)
Parasites , Viruses , Wasps , Animals , Humans , Ecosystem , Virome
5.
Viruses ; 15(9)2023 08 31.
Article in English | MEDLINE | ID: mdl-37766257

ABSTRACT

This study reports the virome investigation of pollinator species and other floral visitors associated with plants from the south of Bahia: Aphis aurantii, Atrichopogon sp., Dasyhelea sp., Forcipomyia taiwana, and Trigona ventralis hoozana. Studying viruses in insects associated with economically important crops is vital to understand transmission dynamics and manage viral diseases that pose as threats for global food security. Using literature mining and public RNA next-generation sequencing data deposited in the NCBI SRA database, we identified potential vectors associated with Malvaceae plant species and characterized the microbial communities resident in these insects. Bacteria and Eukarya dominated the metagenomic analyses of all taxon groups. We also found sequences showing similarity to elements from several viral families, including Bunyavirales, Chuviridae, Iflaviridae, Narnaviridae, Orthomyxoviridae, Rhabdoviridae, Totiviridae, and Xinmoviridae. Phylogenetic analyses indicated the existence of at least 16 new viruses distributed among A. aurantii (3), Atrichopogon sp. (4), Dasyhelea sp. (3), and F. taiwana (6). No novel viruses were found for T. ventralis hoozana. For F. taiwana, the available libraries also allowed us to suggest possible vertical transmission, while for A. aurantii we followed the infection profile along the insect development. Our results highlight the importance of studying the virome of insect species associated with crop pollination, as they may play a crucial role in the transmission of viruses to economically important plants, such as those of the genus Theobroma, or they will reduce the pollination process. This information may be valuable in developing strategies to mitigate the spread of viruses and protect the global industry.


Subject(s)
Virome , Viruses , Humans , Bees , Animals , Phylogeny , Insecta , Viruses/genetics , Crops, Agricultural
6.
Int J Mol Sci ; 24(14)2023 Jul 20.
Article in English | MEDLINE | ID: mdl-37511472

ABSTRACT

The fungus Moniliophthora perniciosa secretes protein effectors that manipulate the physiology of the host plant, but few effectors of this fungus have had their functions confirmed. We performed functional characterization of a promising candidate effector of M. perniciosa. The inoculation of rBASIDIN at 4 µmol L-1 in the mesophyll of leaflets of Solanum lycopersicum caused symptoms of shriveling within 6 h without the presence of necrosis. However, when sprayed on the plant at a concentration of 11 µmol L-1, it caused wilting symptoms only 2 h after application, followed by necrosis and cell death at 48 h. rBASIDIN applied to Theobroma cacao leaves at the same concentration caused milder symptoms. rBASIDIN caused hydrogen peroxide production in leaf tissue, damaging the leaf membrane and negatively affecting the photosynthetic rate of Solanum lycopersicum plants. Phylogenetic analysis indicated that BASIDIN has orthologs in other phytopathogenic basidiomycetes. Analysis of the transcripts revealed that BASIDIN and its orthologs are expressed in different fungal species, suggesting that this protein is differentially regulated in these basidiomycetes. Therefore, the results of applying BASIDIN allow the inference that it is an effector of the fungus M. perniciosa, with a strong potential to interfere in the defense system of the host plant.


Subject(s)
Agaricales , Basidiomycota , Cacao , Cytisus , Cacao/microbiology , Phylogeny , Agaricales/metabolism , Basidiomycota/genetics , Necrosis , Plant Diseases/microbiology
7.
PLoS Negl Trop Dis ; 17(4): e0010862, 2023 04.
Article in English | MEDLINE | ID: mdl-37043542

ABSTRACT

Phlebotomine sand flies are of global significance as important vectors of human disease, transmitting bacterial, viral, and protozoan pathogens, including the kinetoplastid parasites of the genus Leishmania, the causative agents of devastating diseases collectively termed leishmaniasis. More than 40 pathogenic Leishmania species are transmitted to humans by approximately 35 sand fly species in 98 countries with hundreds of millions of people at risk around the world. No approved efficacious vaccine exists for leishmaniasis and available therapeutic drugs are either toxic and/or expensive, or the parasites are becoming resistant to the more recently developed drugs. Therefore, sand fly and/or reservoir control are currently the most effective strategies to break transmission. To better understand the biology of sand flies, including the mechanisms involved in their vectorial capacity, insecticide resistance, and population structures we sequenced the genomes of two geographically widespread and important sand fly vector species: Phlebotomus papatasi, a vector of Leishmania parasites that cause cutaneous leishmaniasis, (distributed in Europe, the Middle East and North Africa) and Lutzomyia longipalpis, a vector of Leishmania parasites that cause visceral leishmaniasis (distributed across Central and South America). We categorized and curated genes involved in processes important to their roles as disease vectors, including chemosensation, blood feeding, circadian rhythm, immunity, and detoxification, as well as mobile genetic elements. We also defined gene orthology and observed micro-synteny among the genomes. Finally, we present the genetic diversity and population structure of these species in their respective geographical areas. These genomes will be a foundation on which to base future efforts to prevent vector-borne transmission of Leishmania parasites.


Subject(s)
Leishmania , Leishmaniasis, Cutaneous , Phlebotomus , Psychodidae , Animals , Humans , Phlebotomus/parasitology , Psychodidae/parasitology , Leishmania/genetics , Genomics
8.
Int J Mol Sci ; 24(6)2023 Mar 16.
Article in English | MEDLINE | ID: mdl-36982760

ABSTRACT

Significant scientific advances to elucidate the Moniliophthora perniciosa pathosystem have been achieved in recent years, but the molecular biology of this pathogen-host interaction is still a field with many unanswered questions. In order to present insights at the molecular level, we present the first systematic review on the theme. All told, 1118 studies were extracted from public databases. Of these, 109 were eligible for the review, based on the inclusion and exclusion criteria. The results indicated that understanding the transition from the biotrophic-necrotrophic phase of the fungus is crucial for control of the disease. Proteins with strong biotechnological potential or that can be targets for pathosystem intervention were identified, but studies regarding possible applications are still limited. The studies identified revealed important genes in the M. perniciosa-host interaction and efficient molecular markers in the search for genetic variability and sources of resistance, with Theobroma cacao being the most common host. An arsenal of effectors already identified and not explored in the pathosystem were highlighted. This systematic review contributes to the understanding of the pathosystem at the molecular level, offering new insights and proposing different paths for the development of new strategies to control witches' broom disease.


Subject(s)
Agaricales , Cacao , Cacao/genetics , Cacao/microbiology , Phytoplasma Disease , Plant Diseases/genetics , Plant Diseases/microbiology , Molecular Biology , Host-Pathogen Interactions/genetics , Agaricales/genetics
9.
J Fungi (Basel) ; 9(3)2023 Mar 15.
Article in English | MEDLINE | ID: mdl-36983529

ABSTRACT

Viruses that infect fungi are known as mycoviruses and are characterized by the lack of an extracellular phase. In recent years, the advances on nucleic acids sequencing technologies have led to a considerable increase in the number of fungi-infecting viral species described in the literature, with a special interest in assessing potential applications as fungal biocontrol agents. In the present study, we performed a comprehensive review using Scopus, Web of Science, and PubMed databases to mine mycoviruses data to explore their molecular features and their use in biotechnology. Our results showed the existence of 267 mycovirus species, of which 189 are recognized by the International Committee on Taxonomy of Viruses (ICTV). The majority of the mycoviruses identified have a dsRNA genome (38.6%), whereas the Botourmiaviridae (ssRNA+) alone represents 14% of all mycoviruses diversity. Regarding fungal hosts, members from the Sclerotinicaeae appeared as the most common species described to be infected by mycoviruses, with 16 different viral families identified so far. It is noteworthy that such results are directly associated with the high number of studies and strategies used to investigate the presence of viruses in members of the Sclerotinicaeae family. The knowledge about replication strategy and possible impact on fungi biology is available for only a small fraction of the mycoviruses studied, which is the main limitation for considering these elements potential targets for biotechnological applications. Altogether, our investigation allowed us to summarize the general characteristics of mycoviruses and their hosts, the consequences, and the implications of this knowledge on mycovirus-fungi interactions, providing an important source of information for future studies.

10.
Braz J Microbiol ; 54(2): 779-790, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36869213

ABSTRACT

Non-diphtheria Corynebacterium species (NDC) belonging to the human skin and mucosa microbiota are frequently neglected as contaminants. However, reports of human infections by Corynebacterium spp. have increased considerably in recent years. In this study, a group of six NDC isolates of urine (n = 5) and sebaceous cyst (n = 1) from two South American countries were identified at genus level or misidentified based on API® Coryne and genetic/molecular analyses. The 16S rRNA (99.09-99.56%) and rpoB (96.18-97.14%) gene sequence similarities of the isolates were higher when compared with Corynebacterium aurimucosum DSM 44532 T. Multilocus sequence analysis (MLSA) indicated that these six NDC isolates compose a distinctive phylogenetic clade. Genome-based taxonomic analysis with the whole-genome sequences was able to separate these six isolates from other known Corynebacterium type strains. Average nucleotide identity (ANI), average amino acid identity (AAI), and digital DNA-DNA hybridization (dDDH) values between closely related type strains and the six isolates were considerably lower than the currently recommended threshold values for species circumscription. Phylogenetic and genomic taxonomy analyses indicated these microorganisms as a novel Corynebacterium species, for which we formally propose the name Corynebacterium guaraldiae sp. nov. with isolate 13T (= CBAS 827T = CCBH 35012T) as type strain.


Subject(s)
Corynebacterium , DNA , Humans , Sequence Analysis, DNA , Phylogeny , RNA, Ribosomal, 16S/genetics , Corynebacterium/genetics , DNA, Bacterial/genetics , Bacterial Typing Techniques , Fatty Acids/chemistry , Nucleic Acid Hybridization
11.
Pathogens ; 12(2)2023 Feb 09.
Article in English | MEDLINE | ID: mdl-36839559

ABSTRACT

Theobroma cacao is one of the main crops of economic importance in the world as the source of raw material for producing chocolate and derivatives. The crop is the main source of income for thousands of small farmers, who produce more than 80% of the world's cocoa supply. However, the emergence, re-emergence and proliferation of pathogens, such as Ceratocystis spp., the causative agent of Ceratocystis wilt disease and canker disease, have been affecting the sustainability of many crops. Fungal control is laborious, often depending on fungicides that are expensive and/or toxic to humans, prompting researchers to look for new solutions to counteract the proliferation of these pathogens, including the use of biological agents such as mycoviruses. In this study, we investigated the diversity of microorganisms associated with the T. cacao pathogens Ceratocystis cacaofunesta and Ceratocystis fimbriata with a focus on the virome using RNA sequencing data available in public databases. We used a comprehensive bioinformatics pipeline containing several steps for viral sequence enrichment and took advantage of an integrated assembly step composed of different assemblers followed by sequence similarity searches using NCBI nonredundant databases. Our strategy was able to identify four putative C. cacaofunesta viruses (hypovirus, sclerotimonavirus, alphapartitivirus and narnavirus) and six C. fimbriata viruses (three alphaendornaviruses, one victorivirus and two mitoviruses). All the viral sequences identified showed similarity to viral genomes in public databases only at the amino acid level, likely representing new viral species. Of note, we present the first report of viruses associated with the cacao pathogens C. cacaofunesta and C. fimbriata and the second report of viral species infecting members of the Ceratocystidaceae family. Our findings highlight the need for further prospective studies to uncover the real diversity of fungus-infecting viruses that can contribute to the development of new management strategies.

12.
Genomics ; 114(6): 110517, 2022 11.
Article in English | MEDLINE | ID: mdl-36306958

ABSTRACT

Aspergillus welwitschiae causes bole rot disease in sisal (Agave sisalana and related species) which affects the production of natural fibers in Brazil, the main worldwide producer of sisal fibers. This fungus is a saprotroph with a broad host range. Previous research established A. welwitschiae as the only causative agent of bole rot in the field, but little is known about the evolution of this species and its strains. In this work, we performed a comparative genomics analysis of 40 Aspergillus strains. We show the conflicting molecular identity of this species, with one sisal-infecting strain sharing its last common ancestor with Aspergillus niger, having diverged only 833 thousand years ago. Furthermore, our analysis of positive selection reveals sites under selection in genes coding for siderophore transporters, Sodium­calcium exchangers, and Phosphatidylethanolamine-binding proteins (PEBPs). Herein, we discuss the possible impacts of these gene functions on the pathogenicity in sisal.


Subject(s)
Agave , Agave/genetics , Brazil , Aspergillus/genetics
13.
Front Microbiol ; 13: 874319, 2022.
Article in English | MEDLINE | ID: mdl-35992690

ABSTRACT

Agroforestry systems (AFS) for cocoa production combine traditional land-use practices with local biodiversity conservation, resulting in both ecological and agricultural benefits. The cacao-cabruca AFS model is widely implemented in regions of the Brazilian Atlantic Forest. Carpotroche brasiliensis (Raddi) A. Gray (Achariaceae) is a tree found in cabruca landscapes that is often used for reforestation and biotechnological applications. Despite its importance, we still lack information about viruses circulating in C. brasiliensis, particularly considering the possibility of spillover that could affect cocoa production. In our study, we analyzed the Carpotroche brasiliensis virome from Atlantic Forest and cacao-cabruca AFS regions using metatranscriptomics from several vegetative and reproductive organs. Our results revealed a diverse virome detecting near-complete or partial coding sequences of single- and double-stranded DNA and RNA viruses classified into at least six families (Botourmiaviridae, Bromoviridae, Caulimoviridae, Genomoviridae, Mitoviridae, and Rhabdoviridae) plus unclassified elements. We described with high confidence the near-complete and the partial genomes of two tentative novel viruses: Carpotroche-associated ilarvirus and Carpotroche-associated genomovirus, respectively. Interestingly, we also described sequences likely derived from a rhabdovirus, which could represent a novel member of the genus Gammanucleorhabdovirus. We observed higher viral diversity in cacao-cabruca AFS and reproductive organs of C. brasiliensis with preferential tropism to fruits, which could directly affect production. Altogether, our results provide data to better understand the virome in this unexplored agroecological interface, such as cacao-cabruca AFS and forest ecosystem, providing information on the aspects of virus-plant interactions.

14.
J Fungi (Basel) ; 8(4)2022 Apr 06.
Article in English | MEDLINE | ID: mdl-35448604

ABSTRACT

The rubber tree, Hevea brasiliensis, is a neotropical Amazonian species. Despite its high economic value and fungi associated with native individuals, in its original area in Brazil, it has been scarcely investigated and only using culture-dependent methods. Herein, we integrated in silico approaches with novel field/experimental approaches and a case study of shotgun metagenomics and small RNA metatranscriptomics of an adult individual. Scientific literature, host fungus, and DNA databases are biased to fungal taxa, and are mainly related to rubber tree diseases and in non-native ecosystems. Metabarcoding retrieved specific phyllospheric core fungal communities of all individuals, adults, plantlets, and leaves of the same plant, unravelling hierarchical structured core mycobiomes. Basidiomycotan yeast-like fungi that display the potential to produce antifungal compounds and a complex of non-invasive ectophytic parasites (Sooty Blotch and Flyspeck fungi) co-occurred in all samples, encompassing the strictest core mycobiome. The case study of the same adult tree (previously studied using culture-dependent approach) analyzed by amplicon, shotgun metagenomics, and small RNA transcriptomics revealed a high relative abundance of insect parasite-pathogens, anaerobic fungi and a high expression of Trichoderma (a fungal genus long reported as dominant in healthy wild rubber trees), respectively. Altogether, our study unravels new and intriguing information/hypotheses of the foliar mycobiome of native H. brasiliensis, which may also occur in other native Amazonian trees.

15.
Front Microbiol ; 13: 1053562, 2022.
Article in English | MEDLINE | ID: mdl-36817107

ABSTRACT

Introduction: Theobroma cacao, the cocoa tree, is a target for pathogens, such as fungi from the genera Phytophthora, Moniliophthora, Colletotrichum, Ceratocystis, among others. Some cacao pathogens are restricted to specific regions of the world, such as the Cacao swollen shoot virus (CSSV) in West African countries, while others are expanding geographically, such as Moniliophthora roreri in the Americas. M. roreri is one of the most threatening cacao pathogens since it directly attacks the cacao pods driving a significant reduction in production, and therefore economic losses. Despite its importance, the knowledge about the microenvironment of this pathogen and the cocoa pods is still poorly characterized. Methods: Herein we performed RNA sequencing of spores in differential stages of culture in a medium supplemented with cacao pod extract and mycelium collected of the susceptible variety ICT 7121 naturally infected by the pathogen to evaluate the diversity and transcriptional activity of microorganisms associated with the in vitro sporulation of M. roreri. Results: Our data revealed a great variety of fungi and bacteria associated with M. roreri, with an exceptional diversity of individuals from the genus Trichoderma sp. Interestingly, the dynamics of microorganisms from different kingdoms varied proportionally, suggesting they are somehow affected by M. roreri culture time. We also identified three sequences similar to viral genomes from the Narnaviridae family, posteriorly confirmed by phylogenetic analysis as members of the genus Narnavirus. Screening of M. roreri public datasets indicated the virus sequences circulating in samples from Ecuador, suggesting a wide spread of these elements. Of note, we did not identify traces of the viral sequences in the M. roreri genome or DNA sequencing, restricting the possibility of these sequences representing endogenized elements. Discussion: To the best of our knowledge, this is the first report of viruses infecting the fungus of the genus Moniliophthora and only the third description of viruses that are able to parasite elements from the Marasmiaceae family.

16.
Microorganisms ; 9(8)2021 Aug 10.
Article in English | MEDLINE | ID: mdl-34442783

ABSTRACT

Sisal is a common name for different plant varieties in the genus Agave (especially Agave sisalana) used for high-quality natural leaf fiber extraction. Despite the economic value of these plants, we still lack information about the diversity of viruses (virome) in non-tequilana species from the genus Agave. In this work, by associating RNA and DNA deep sequencing we were able to identify 25 putative viral species infecting A. sisalana, A. fourcroydes, and Agave hybrid 11648, including one strain of Cowpea Mild Mottle Virus (CPMMV) and 24 elements likely representing new viruses. Phylogenetic analysis indicated they belong to at least six viral families: Alphaflexiviridae, Betaflexiviridae, Botourmiaviridae, Closteroviridae, Partitiviridae, Virgaviridae, and three distinct unclassified groups. We observed higher viral taxa richness in roots when compared to leaves and stems. Furthermore, leaves and stems are very similar diversity-wise, with a lower number of taxa and dominance of a single viral species. Finally, approximately 50% of the identified viruses were found in all Agave organs investigated, which suggests that they likely produce a systemic infection. This is the first metatranscriptomics study focused on viral identification in species from the genus Agave. Despite having analyzed symptomless individuals, we identified several viruses supposedly infecting Agave species, including organ-specific and systemic species. Surprisingly, some of these putative viruses are probably infecting microorganisms composing the plant microbiota. Altogether, our results reinforce the importance of unbiased strategies for the identification and monitoring of viruses in plant species, including those with asymptomatic phenotypes.

17.
Transbound Emerg Dis ; 68(6): 3070-3074, 2021 Nov.
Article in English | MEDLINE | ID: mdl-33421326

ABSTRACT

An 11-year-old male mixed-breed cat, with exclusively indoor life, presented 3 cough episodes after the owners tested positive by RT-PCR for SARS-CoV-2. The house is inhabited by 5 people (3 adults and 2 children), and 2 of the adults have shown mild symptoms associated with throat discomfort. The cat was vaccinated, had no history of any previous disease, and tested negative for feline coronavirus (FCoV), feline immunodeficiency virus (FIV) and feline leukaemia virus (FeLV). Rectal sample collected from the cat was positive for SARS-CoV-2 by RT-PCR. Viral genome sequences recovered from human and cat samples showed an average 99.4% sequence identity. This is the first report of genome sequences of SARS-CoV-2 recovered from a cat and its owner in Latin America.


Subject(s)
COVID-19 , Cat Diseases , Cats/virology , SARS-CoV-2/isolation & purification , Animals , COVID-19/veterinary , Cat Diseases/virology , Humans , Immunodeficiency Virus, Feline , Latin America , Leukemia Virus, Feline , Male
18.
RNA ; 26(5): 581-594, 2020 05.
Article in English | MEDLINE | ID: mdl-31996404

ABSTRACT

Endogenous viral elements (EVEs) are found in many eukaryotic genomes. Despite considerable knowledge about genomic elements such as transposons (TEs) and retroviruses, we still lack information about nonretroviral EVEs. Aedes aegypti mosquitoes have a highly repetitive genome that is covered with EVEs. Here, we identified 129 nonretroviral EVEs in the AaegL5 version of the A. aegypti genome. These EVEs were significantly associated with TEs and preferentially located in repeat-rich clusters within intergenic regions. Genome-wide transcriptome analysis showed that most EVEs generated transcripts although only around 1.4% were sense RNAs. The majority of EVE transcription was antisense and correlated with the generation of EVE-derived small RNAs. A single genomic cluster of EVEs located in a 143 kb repetitive region in chromosome 2 contributed with 42% of antisense transcription and 45% of small RNAs derived from viral elements. This region was enriched for TE-EVE hybrids organized in the same coding strand. These generated a single long antisense transcript that correlated with the generation of phased primary PIWI-interacting RNAs (piRNAs). The putative promoter of this region had a conserved binding site for the transcription factor Cubitus interruptus, a key regulator of the flamenco locus in Drosophila melanogaster Here, we have identified a single unidirectional piRNA cluster in the A. aegypti genome that is the major source of EVE transcription fueling the generation of antisense small RNAs in mosquitoes. We propose that this region is a flamenco-like locus in A. aegypti due to its relatedness to the major unidirectional piRNA cluster in Drosophila melanogaster.


Subject(s)
Aedes/genetics , Genome, Insect/genetics , RNA, Small Interfering/genetics , Retroelements/genetics , Animals , Binding Sites/genetics , Cadherins/genetics , Culicidae/genetics , DNA-Binding Proteins/genetics , Drosophila Proteins/genetics , Drosophila melanogaster/genetics , Homeodomain Proteins/genetics , Promoter Regions, Genetic , Transcription Factors/genetics
19.
Toxins (Basel) ; 11(11)2019 10 30.
Article in English | MEDLINE | ID: mdl-31671681

ABSTRACT

Aspergillus welwitschiae is a species of the Nigri section of the genus Aspergillus. In nature, it is usually a saprotroph, decomposing plant material. However, it causes the bole rot disease of Agave sisalana (sisal), a plant species used for the extraction of hard natural fibers, causing great economic loss to this culture. In this study, we isolated and sequenced one genome of A. welwitschiae (isolate CCMB 674 (Collection of Cultures of Microorganisms of Bahia)) from the stem tissues of sisal and performed in silico and wet lab experimental strategies to describe its ability to produce mycotoxins. CCMB 674 possesses 64 secondary metabolite gene clusters (SMGCs) and, under normal conditions, it produces secondary metabolism compounds that could disturb the cellular cycle of sisal or induce abnormalities in plant growth, such as malformin C. This isolate also produces a pigment that might explain the characteristic red color of the affected tissues. Additionally, this isolate is defective for the production of fumonisin B1, and, despite bearing the full cluster for the synthesis of this compound, it did not produce ochratoxin A. Altogether, these results provide new information on possible strategies used by the fungi during the sisal bole rot, helping to better understand this disease and how to control it.


Subject(s)
Agave/growth & development , Agave/microbiology , Aspergillus/genetics , Aspergillus/metabolism , Cell Cycle/drug effects , Mycotoxins/biosynthesis , Secondary Metabolism , Amino Acid Sequence , Brazil
20.
Viruses ; 10(12)2018 12 06.
Article in English | MEDLINE | ID: mdl-30563205

ABSTRACT

Arthropod vectors control the replication of arboviruses through their innate antiviral immune responses. In particular, the RNA interference (RNAi) pathways are of notable significance for the control of viral infections. Although much has been done to understand the role of RNAi in vector populations, little is known about its importance in non-vector mosquito species. In this study, we investigated the presence of an RNAi response in Toxorhynchites amboinensis, which is a non-blood feeding species proposed as a biological control agent against pest mosquitoes. Using a derived cell line (TRA-171), we demonstrate that these mosquitoes possess a functional RNAi response that is active against a mosquito-borne alphavirus, Semliki Forest virus. As observed in vector mosquito species, small RNAs are produced that target viral sequences. The size and characteristics of these small RNAs indicate that both the siRNA and piRNA pathways are induced in response to infection. Taken together, this data suggests that Tx. amboinensis are able to control viral infections in a similar way to natural arbovirus vector mosquito species. Understanding their ability to manage arboviral infections will be advantageous when assessing these and similar species as biological control agents.


Subject(s)
Culicidae/genetics , Culicidae/virology , RNA Interference , Semliki forest virus/genetics , Alphavirus Infections/immunology , Animals , Biological Control Agents , Cell Line , Culicidae/cytology , High-Throughput Nucleotide Sequencing , Immunity, Innate , Mosquito Vectors/genetics , Mosquito Vectors/virology , RNA, Small Interfering/genetics , Semliki forest virus/immunology , Virus Replication
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