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Dezordi, F. Z.

Publications and source records attributed to Dezordi, F. Z..

3 recordsLinked to original sources

RNA virome of sylvatic mosquitoes from northeast Brazil reveals a divergent and diverse insect-specific viral community

Mosquitoes can transmit several pathogenic viruses to humans, but their natural viral community is also composed of a myriad of other viruses such as insect-specific viruses (ISV) and those that infect symbiotic microorganisms. Besides a growing number of studies investigating the mosquito virome the majority are focused on few urban species and relatively little is known about the virome of sylvatic mosquitoes particularly in high biodiverse brazilian biomes. Here, we characterized the RNA virome of 10 sylvatic mosquitos species from Atlantic forest remains at a sylvatic-urban interface in Northeast Brazil employing a metatranscriptomic approach. A total of 16 viral families were detected. The phylogenetic reconstructions of 14 viral families revealed that the majority of the sequences are putative ISVs. The phylogenetic positioning and, in most cases, the association with a high RdRp amino acid divergence from other known viruses suggests that the viruses characterized here represent at least 34 new viral species. Therefore, the sylvatic mosquitoes viral community is majorly composed of highly divergent viruses highlighting the limited knowledge we still have about the natural virome of mosquitoes in general. Moreover, we found that none of the viruses recovered were shared between the species investigated. These findings will help to understand the interactions and coevolution between mosquitoes and viruses in nature. ImportanceMosquitoes are medically important insects as they transmit pathogenic viruses to humans and animals during blood feeding. However, their natural microbiota is also composed of a diverse set of viruses that cause no harm to the insect and other hosts, such as ISVs. In this study, we characterized the RNA virome of sylvatic mosquitoes from Northeast Brazil using unbiased metatranscriptomic sequencing and in depth bioinformatics approaches. Our analysis revealed that these mosquitoes species harbor a diverse set of highly divergent viruses and the majority comprises new viral species. Our findings revealed many new virus lineages characterized for the first time broadening our understanding about the natural interaction between mosquitoes and viruses. Lastly, it also provided several complete genomes that warrants further assessment for mosquito and vertebrate host pathogenicity and their potential interference with pathogenic arboviruses.

genomics↗

Ancient origin of Jingchuvirales derived glycoproteins integrated in arthropod genomes

Endogenous virus elements (EVEs) are viral-derived sequences integrated into their host genomes. EVEs of the Jingchuvirales order were detected in a wide range of insect genomes covering several distantly related families and Jingchuvirales-derived glycoproteins were recently associated by our group with the origin of a putative new retrovirus based on a glycoprotein captured by a mosquito retrotransposon. But, except for mosquitoes, there is a lack of a more detailed understanding of the endogenization mechanism, timing and frequency per viral lineages. Here we screened Jingchuvirales glycoprotein-derived EVEs (Jg-EVEs) in eukaryotic genomes. We found six distinct endogenization events of Jg-EVEs, that belong to two out of five known Jingchuvirales families (Chuviridae and Natareviridae). For seven arthropod families bearing Jg-EVEs there is no register of bona fide circulating chuvirus infection. Hence, our results show that Jingchuvirales viruses infected or still infect these host families, expanding their known host range. We estimated that two endogenization events occurred in the ancestors of the Myrmicinae-Ponerinae subfamilies (Pteromalidae - Hymenoptera order) around 155[~]54.8 MyA and Bombus genus (Hemiptera order) around (36[~]2 MyA). Although we found abundant evidence of LTR-Gypsy retrotransposons fragments associated with the glycoprotein in Hymenoptera and other insect orders, there is no evidence of potential functional glycoprotein capture. Our results show that the widespread distribution of Jingchuvirales glycoproteins in extant Arhtropods is a result of multiple ancient endogenization events and that these viruses fossils are being vertically inherited for millions of years through the Arthropods evolutionary tree. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=142 HEIGHT=200 SRC="FIGDIR/small/497255v1_ufig1.gif" ALT="Figure 1"> View larger version (42K): org.highwire.dtl.DTLVardef@194f47org.highwire.dtl.DTLVardef@1a3dd24org.highwire.dtl.DTLVardef@10b77bdorg.highwire.dtl.DTLVardef@1e21ffb_HPS_FORMAT_FIGEXP M_FIG C_FIG

evolutionary biology↗

In and outs of Chuviridae endogenous viral elements: origin of a retrovirus and signature of ancient and ongoing arms race in mosquito genomes

BackgroundEndogenous viral elements (EVEs) are sequences of viral origin integrated into the host genome. EVEs have been characterized in various insect genomes, including mosquitoes. A large EVE content has been found in Aedes aegypti and Aedes albopictus genomes among which a recently described Chuviridae viral family is of particular interest, owing to the abundance of EVEs derived from it, the discrepancy in the endogenized gene regions and the frequent association with retrotransposons from the BEL-Pao superfamily. In order to better understand the endogenization process of chuviruses and the association between chuvirus glycoproteins and BEL-Pao retrotransposons, we performed a comparative genomics and evolutionary analysis of chuvirus-derived EVEs found in 37 mosquito genomes. ResultsWe identified 428 EVEs belonging to the Chuviridae family confirming the wide discrepancy between the number of genomic regions endogenized: 409 glycoproteins, 18 RNA-dependent RNA polymerases and one nucleoprotein region. Most of the glycoproteins (263 out of 409) are associated specifically with retroelements from the Pao family. Focusing only on well assembled Pao retroelement copies, we estimated that 263 out of 379 Pao elements are associated with chuvirus-derived glycoproteins. Seventy-three potentially active Pao copies were found to contain glycoproteins into their LTR boundaries. Thirteen out of these were classified as complete and likely autonomous copies, with a full LTR structure and protein domains. We also found 116 Pao copies with no trace of glycoproteins and 37 solo glycoproteins. All potential autonomous Pao copies, contained highly similar LTRs, suggesting a recent/current activity of these elements in the mosquito genomes. ConclusionEvolutionary analysis revealed that most of the glycoproteins found are likely derived from a single or few glycoprotein endogenization events associated with a recombination event with a Pao ancestral element. A potential fully functional Pao-chuvirus hybrid (named Anakin) emerged and the glycoprotein was further replicated through retrotransposition. However, a number of solo glycoproteins, not associated with Pao elements, can still be found in some mosquito genomes 114 million years later, suggesting that these glycoproteins were likely domesticated by the host genome and may participate in an antiviral defense mechanism against both chuvirus and Anakin retrovirus.

evolutionary biology↗