181 research outputs found

    Evolutionary history of LINE-1 in the major clades of placental mammals

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    BACKGROUND: LINE-1 constitutes an important component of mammalian genomes. It has a dynamic evolutionary history characterized by the rise, fall and replacement of subfamilies. Most data concerning LINE-1 biology and evolution are derived from the human and mouse genomes and are often assumed to hold for all placentals. METHODOLOGY: To examine LINE-1 relationships, sequences from the 3â€Č region of the reverse transcriptase from 21 species (representing 13 orders across Afrotheria, Xenarthra, Supraprimates and Laurasiatheria) were obtained from whole genome sequence assemblies, or by PCR with degenerate primers. These sequences were aligned and analysed. PRINCIPAL FINDINGS: Our analysis reflects accepted placental relationships suggesting mostly lineage-specific LINE-1 families. The data provide clear support for several clades including Glires, Supraprimates, Laurasiatheria, Boreoeutheria, Xenarthra and Afrotheria. Within the afrotherian LINE-1 (AfroLINE) clade, our tree supports Paenungulata, Afroinsectivora and Afroinsectiphillia. Xenarthran LINE-1 (XenaLINE) falls sister to AfroLINE, providing some support for the Atlantogenata (Xenarthra+Afrotheria) hypothesis. SIGNIFICANCE: LINEs and SINEs make up approximately half of all placental genomes, so understanding their dynamics is an essential aspect of comparative genomics. Importantly, a tree of LINE-1 offers a different view of the root, as long edges (branches) such as that to marsupials are shortened and/or broken up. Additionally, a robust phylogeny of diverse LINE-1 is essential in testing that site-specific LINE-1 insertions, often regarded as homoplasy-free phylogenetic markers, are indeed unique and not convergent

    Inventaire et Biogéographie des rongeurs du Niger : nuisance aux cultures, implications dans certains problÚmes de santé publique et vétérinaire

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    71 pagesRapport de Coopération de Gauthier DOBIGNY (CSN Niger 1999-200)An inventory of rodent species from Niger was performed during 1999 and 2000. It covers all the major biogeographic regions (Sudan, Sahel, Sahara) and relies on 55 sites scattered all over the counrty. Unambiguous species-specific diagnoses were provided by cytotaxonomic surveys. Implications in terms of taxonomy, biodiversity, biogeography, damages to cultures and stocks as well as potential human health problems are discussed

    Zoonotic emergence at the animal-environment-human interface: the forgotten urban socio-ecosystems

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    Preprint of a review paper on zoonotic emergence risk at the animal-human-environment interface within urban and peri-urban socio-ecosystems.Other funding source: SCARIA project (Belmont Forum, Pathways to Sustainability, ANR-21-SDG1-0005-01

    Urban market gardening and rodent-borne pathogenic Leptospira in arid zones: a case study in Niamey, Niger

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    Leptospirosis essentially affects human following contact with rodent urine-contaminated water. As such, it was mainly found associated with rice culture, recreational activities and flooding. This is also the reason why it has mainly been investigated in temperate as well as warm and humid regions, while arid zones have been only very occasionally monitored for this disease. In particular, data for West African countries are extremely scarce. Here, we took advantage of an extensive survey of urban rodents in Niamey, Niger, in order to look for rodent-borne pathogenic[i] Leptospira[/i] species presence and distribution across the city. To do so, we used high throughput bacterial 16S-based metabarcoding, [i]lipL32[/i] gene-targeting RT-PCR, rrs gene sequencing and VNTR typing as well as GIS-based multivariate spatial analysis. Our results show that leptospires seem absent from the core city where usual [i]Leptospira[/i] reservoir rodent species (namely [i]R. rattus[/i] and [i]M. natalensis[/i]) are yet abundant. On the contrary, [i]L. kirschneri[/i] was detected in [i]Arvicanthis niloticus[/i] and [i]Cricetomys gambianus[/i], two rodent species that are restricted to irrigated cultures within the city. Moreover, the VNTR profiles showed that rodent-borne leptospires in Niamey belong to previously undescribed serovars. Altogether, our study points towards the importance of market gardening in maintain and circulation of leptospirosis within Sahelian cities. In Africa, irrigated urban agriculture constitutes a pivotal source of food supply, especially in the context of the ongoing extensive urbanization of the continent. With this in mind, we speculate that leptospirosis may represent a zoonotic disease of concern also in arid regions that would deserve to be more rigorously surveyed, especially in urban agricultural settings

    Economic costs of invasive rodents worldwide : the tip of the iceberg

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    ACKNOWLEDGEMENTS We are extremely grateful to the organizers of the InvaCost workshop that allowed the genesis of this project, as well as to all contacted people who kindly answered to our requests for information about the costs of invasive rodents. We thank L. Nuninger and C. Assailly for their work in the initial project, and María Angulo and Nuria Cerdá for their help in generating the Fig. 3. Last, the authors thank Dr. Steffen Oppel and another anonymous reviewer for their thorough revision of the article which greatly improved it. Funding Information: This work was supported by the French National Research Agency (ANR-14-CE02-0021) and the BNP-Paribas Foundation Climate Initiative for funding the Invacost project which allowed the construction of the InvaCost database. This work was initiated following a workshop funded by the AXA Research Fund Chair of Invasion Biology. This research was also funded through the 2017-2018 Belmont Forum and BiodivERsA joint call for research proposals, under the BiodivScen ERA-Net COFUND programme. Funds for Elena Angulo and Liliana Ballesteros-Mejia came from the AXA Research Fund Chair of Invasion Biology of University Paris Saclay. Christophe Diagne was funded by the BiodivERsA-Belmont Forum Project ‘‘Alien Scenarios’’ (BMBF/PT DLR 01LC1807C). Ross N. Cuthbert received funding from the Leverhulme Trust (ECF-2021-001). Thomas W. Bodey received funding from the European Union’s Horizon 2020 research and innovation programme Marie SkƂodowska-Curie fellowship (Grant No. 747120). Jean Fantle-Lepczyk received travel support to attend the Invacost workshop from Auburn University School of Forestry and Wildlife Sciences. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD

    Multidirectional chromosome painting substantiates the occurrence of extensive genomic reshuffling within Accipitriformes.

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    BACKGROUND: Previous cross-species painting studies with probes from chicken (Gallus gallus) chromosomes 1-10 and a paint pool of nineteen microchromosomes have revealed that the drastic karyotypic reorganization in Accipitridae is due to extensive synteny disruptions and associations. However, the number of synteny association events and identities of microchromosomes involved in such synteny associations remain undefined, due to the lack of paint probes derived from individual chicken microchromosomes. Moreover, no genome-wide homology map between Accipitridae species and other avian species with atypical karyotype organization has been reported till now, and the karyotype evolution within Accipitriformes remains unclear. RESULTS: To delineate the synteny-conserved segments in Accipitridae, a set of painting probes for the griffon vulture, Gyps fulvus (2n = 66) was generated from flow-sorted chromosomes. Together with previous generated probes from the stone curlew, Burhinus oedicnemus (2n = 42), a Charadriiformes species with atypical karyotype organization, we conducted multidirectional chromosome painting, including reciprocal chromosome painting between B. oedicnemus and G. fulvus and cross-species chromosome painting between B. oedicnemus and two accipitrid species (the Himalayan griffon, G. himalayensis 2n = 66, and the common buzzard, Buteo buteo, 2n = 68). In doing so, genome-wide homology maps between B. oedicnemus and three Accipitridae species were established. From there, a cladistic analysis using chromosomal characters and mapping of chromosomal changes on a consensus molecular phylogeny were conducted in order to search for cytogenetic signatures for different lineages within Accipitriformes. CONCLUSION: Our study confirmed that the genomes of the diurnal birds of prey, especially the genomes of species in Accipitriformes excluding Cathartidae, have been extensively reshuffled when compared to other bird lineages. The chromosomal rearrangements involved include both fusions and fissions. Our chromosome painting data indicated that the Palearctic common buzzard (BBU) shared several common chromosomal rearrangements with some Old World vultures, and was found to be more closely related to other Accipitridae than to Neotropical buteonine raptors from the karyotypic perspective. Using both a chromosome-based cladistic analysis as well as by mapping of chromosomal differences onto a molecular-based phylogenetic tree, we revealed a number of potential cytogenetic signatures that support the clade of Pandionidae (PHA) + Accipitridae. In addition, our cladistic analysis using chromosomal characters appears to support the placement of osprey (PHA) in Accipitridae

    Development of nine microsatellite loci for <i>Trypanosoma lewisi</i>, a potential human pathogen in Western Africa and South-East Asia, and preliminary population genetics analyses

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    This manuscript (word file), presents results obtained while developing microsatellite markers for the parasite T. lewisi and the first population genetics data analysis for this species. This parasite is found mainly in rodents (rats) and is transmitted by fleas. To this respect, it shares the same cycle as other human pathogens (plague, murine typhus) The first results suggest that the subpopulation unit for these parasite populations may be found at very small scales, neighborhoods of cities, and probably even at lower scales (e.g. homes). Data also suggest an operational life cycle (generation time) of 1-2 months, as for other trypanosome species. The excel file contains all raw data. These results, even if they need being refined, but already shed some light on the ecology of this host-parasite-vector system, together with the ecology of other pathogenic agents sharing the same cycle

    Non-English languages enrich scientific knowledge : The example of economic costs of biological invasions

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    We contend that the exclusive focus on the English language in scientific researchmight hinder effective communication between scientists and practitioners or policymakerswhose mother tongue is non-English. This barrier in scientific knowledge and data transfer likely leads to significant knowledge gaps and may create biases when providing global patterns in many fields of science. To demonstrate this, we compiled data on the global economic costs of invasive alien species reported in 15 non-English languages. We compared it with equivalent data from English documents (i.e., the InvaCost database, the most up-to-date repository of invasion costs globally). The comparison of both databases (similar to 7500 entries in total) revealed that non-English sources: (i) capture a greater amount of data than English sources alone (2500 vs. 2396 cost entries respectively); (ii) add 249 invasive species and 15 countries to those reported by English literature, and (iii) increase the global cost estimate of invasions by 16.6% (i.e., US$ 214 billion added to 1.288 trillion estimated fromthe English database). Additionally, 2712 cost entries - not directly comparable to the English database - were directly obtained frompractitioners, revealing the value of communication between scientists and practitioners. Moreover, we demonstrated how gaps caused by overlooking non-English data resulted in significant biases in the distribution of costs across space, taxonomic groups, types of cost, and impacted sectors. Specifically, costs from Europe, at the local scale, and particularly pertaining to management, were largely under-represented in the English database. Thus, combining scientific data from English and non-English sources proves fundamental and enhances data completeness. Considering non-English sources helps alleviate biases in understanding invasion costs at a global scale. Finally, it also holds strong potential for improving management performance, coordination among experts (scientists and practitioners), and collaborative actions across countries. Note: non-English versions of the abstract and figures are provided in Appendix S5 in 12 languages. (c) 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/ by/4.0/).Peer reviewe

    Molecular prevalence, genetic characterization and patterns of Toxoplasma gondii infection in domestic small mammals from Cotonou, Benin

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    Toxoplasmosis, one of the most prevalent parasitic infections in humans and animals, is caused by the intracellular protozoan parasite Toxoplasma gondii. Small mammals play a key role as intermediate reservoir hosts in the maintenance of the T. gondii life cycle. In this study, we estimated the molecular prevalence and provide genetic diversity data for T. gondii in 632 small mammals sampled in four areas of Cotonou city, Benin. Both the brain and heart of each individual were screened through T. gondii-targeting qPCR, and positive samples were then genotyped using a set of 15 T. gondii-specific microsatellites. Prevalence data were statistically analyzed in order to assess the relative impact of individual host characteristics, spatial distribution, composition of small mammal community, and urban landscape features. An overall T. gondii molecular prevalence of 15.2% was found and seven genotypes, all belonging to the Africa 1 lineage, could be retrieved from the invasive black rat Rattus rattus and the native African giant shrew Crocidura olivieri. Statistical analyses did not suggest any significant influence of the environmental parameters used in this study. Rather, depending on the local context, T. gondii prevalence appeared to be associated either with black rat, shrew, or mouse abundance or with the trapping period. Overall, our results highlight the intricate relationships between biotic and abiotic factors involved in T. gondii epidemiology and suggest that R. rattus and C. olivieri are two competent reservoirs for the Africa 1 lineage, a widespread lineage in tropical Africa and the predominant lineage in Benin
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