Molecular evolution of Azagny virus, a newfound hantavirus harbored by the West African pygmy shrew (Crocidura obscurior) in Côte d'Ivoire

<p>Abstract</p> <p>Background</p> <p>Tanganya virus (TGNV), the only shrew-associated hantavirus reported to date from sub-Saharan Africa, is harbored by the Therese's shrew (<it>Crocidura theresae</it>), and is phylogenetically distinct from Thottapalayam virus (TPMV) in the Asian house shrew (<it>Suncus murinus</it>) and Imjin virus (MJNV) in the Ussuri white-toothed shrew (<it>Crocidura lasiura</it>). The existence of myriad soricid-borne hantaviruses in Eurasia and North America would predict the presence of additional hantaviruses in sub-Saharan Africa, where multiple shrew lineages have evolved and diversified.</p> <p>Methods</p> <p>Lung tissues, collected in RNAlater^®, from 39 Buettikofer's shrews (<it>Crocidura buettikoferi</it>), 5 Jouvenet's shrews (<it>Crocidura jouvenetae</it>), 9 West African pygmy shrews (<it>Crocidura obscurior</it>) and 21 African giant shrews (<it>Crocidura olivieri</it>) captured in Côte d'Ivoire during 2009, were systematically examined for hantavirus RNA by RT-PCR.</p> <p>Results</p> <p>A genetically distinct hantavirus, designated Azagny virus (AZGV), was detected in the West African pygmy shrew. Phylogenetic analysis of the S, M and L segments, using maximum-likelihood and Bayesian methods, under the GTR+I+Γ model of evolution, showed that AZGV shared a common ancestry with TGNV and was more closely related to hantaviruses harbored by soricine shrews than to TPMV and MJNV. That is, AZGV in the West African pygmy shrew, like TGNV in the Therese's shrew, did not form a monophyletic group with TPMV and MJNV, which were deeply divergent and basal to other rodent- and soricomorph-borne hantaviruses. Ancestral distributions of each hantavirus lineage, reconstructed using Mesquite 2.74, suggested that the common ancestor of all hantaviruses was most likely of Eurasian, not African, origin.</p> <p>Conclusions</p> <p>Genome-wide analysis of many more hantaviruses from sub-Saharan Africa are required to better understand how the biogeographic origin and radiation of African shrews might have contributed to, or have resulted from, the evolution of hantaviruses.</p

Genetic diversity and phylogeography of Seewis virus in the Eurasian common shrew in Finland and Hungary

Recent identification of a newfound hantavirus, designated Seewis virus (SWSV), in the Eurasian common shrew (Sorex araneus), captured in Switzerland, corroborates decades-old reports of hantaviral antigens in this shrew species from Russia. To ascertain the spatial or geographic variation of SWSV, archival liver tissues from 88 Eurasian common shrews, trapped in Finland in 1982 and in Hungary during 1997, 1999 and 2000, were analyzed for hantavirus RNAs by reverse transcription-polymerase chain reaction. SWSV RNAs were detected in 12 of 22 (54.5%) and 13 of 66 (19.7%) Eurasian common shrews from Finland and Hungary, respectively. Phylogenetic analyses of S- and L-segment sequences of SWSV strains, using maximum likelihood and Bayesian methods, revealed geographic-specific genetic variation, similar to the phylogeography of rodent-borne hantaviruses, suggesting long-standing hantavirus-host co-evolutionary adaptation

Genetic diversity of Imjin virus in the Ussuri white-toothed shrew (Crocidura lasiura) in the Republic of Korea, 2004-2010

Recently, Imjin virus (MJNV), a genetically distinct hantavirus, was isolated from lung tissues of the Ussuri white-toothed shrew (Crocidura lasiura) captured near the demilitarized zone in the Republic of Korea. To clarify the genetic diversity of MJNV, partial M- and L-segment sequences were amplified from lung tissues of 12 of 37 (32.4%) anti-MJNV IgG antibody-positive Ussuri white-toothed shrews captured between 2004 and 2010. A 531-nucleotide region of the M segment (coordinates 2,255 to 2,785) revealed that the 12 MJNV strains differed by 0-12.2% and 0-2.3% at the nucleotide and amino acid levels, respectively. A similar degree of nucleotide (0.2-11.9%) and amino acid (0-3.8%) difference was found in a 632-nucleotide length of the L segment (coordinates 962 to 1,593) of nine MJNV strains. Phylogenetic analyses, based on the partial M and L segments of MJNV strains generated by the neighbor-joining and maximum likelihood methods, showed geographic-specific clustering, akin to the phylogeography of rodent-borne hantaviruses

Divergent lineage of a novel hantavirus in the banana pipistrelle (Neoromicia nanus) in Côte d'Ivoire

Recently identified hantaviruses harbored by shrews and moles (order Soricomorpha) suggest that other mammals having shared ancestry may serve as reservoirs. To investigate this possibility, archival tissues from 213 insectivorous bats (order Chiroptera) were analyzed for hantavirus RNA by RT-PCR. Following numerous failed attempts, hantavirus RNA was detected in ethanol-fixed liver tissue from two banana pipistrelles (Neoromicia nanus), captured near Mouyassué village in Côte d'Ivoire, West Africa, in June 2011. Phylogenetic analysis of partial L-segment sequences using maximum-likelihood and Bayesian methods revealed that the newfound hantavirus, designated Mouyassué virus (MOUV), was highly divergent and basal to all other rodent- and soricomorph-borne hantaviruses, except for Nova virus in the European common mole (Talpa europaea). Full genome sequencing of MOUV and further surveys of other bat species for hantaviruses, now underway, will provide critical insights into the evolution and diversification of hantaviruses

Ring finger protein 126 (RNF126) suppresses ionizing radiation-induced p53-binding protein 1 (53BP1) focus formation

Cells have evolved sophisticated mechanisms to maintain genomic integrity in response to DNA damage. Ionizing radiation (IR)-induced DNA damage results in the formation of IR-induced foci (iRIF) in the nucleus. The iRIF formation is part of the DNA damage response (DDR), which is an essential signaling cascade that must be strictly regulated because either the loss of or an augmented DDR leads to loss of genome integrity. Accordingly, negative regulation of the DDR is as critical as its activation. In this study, we have identified ring finger protein 126 (RNF126) as a negative regulator of the DDR from a screen of iRIF containing 53BP1. RNF126 overexpression abolishes not only the formation of 53BP1 iRIF but also of RNF168, FK2, RAP80, and BRCA1. However, the iRIF formation of H2AX, MDC1, and RNF8 is maintained, indicating that RNF126 acts between RNF8 and RNF168 during the DDR. In addition, RNF126 overexpression consistently results in the loss of RNF168-mediated H2A monoubiquitination at lysine 13/15 and inhibition of the non-homologous end joining capability. Taken together, our findings reveal that RNF126 is a novel factor involved in the negative regulation of DDR, which is important for sustaining genomic integrity

Case study on high-resolution monitoring network of groundwater heat pump system

With the increasing installation of shallow geothermal energy, the importance of thermal impact prediction also increases in the system design stage. In nature, it is general that heterogeneity exists and it can affect the groundwater flow as well as the transport along to the flow. When predicting heat transport under the groundwater heat pump (GWHP) operation, however, impacts of heterogeneity have rarely been considered. In this study, to detect the hydraulic and thermal feedback to the two months of GWHP operation, a dense monitoring network was constructed with 12 monitoring wells at Eumseong-gun, Republic of Korea. The temperature was monitored in high resolution via fiber-optic distributed temperature sensing. During the GWHP operation, a very dynamic flow condition was generated with the hydraulic gradient between 0.005 and 0.07. The maximum temperature change at the nearest monitoring well was 2 ?. Observed hydraulic and thermal responses showed spatially heterogeneous results. While the heterogeneous responses of hydraulic change were stronger near the geothermal wells, those of temperature change were higher near the center of the thermal plume

Protective Immunity Induced by Incorporating Multiple Antigenic Proteins of Toxoplasma gondii Into Influenza Virus-Like Particles

Virus-like particle (VLP) as a highly efficient vaccine platform has been used to present single or multiple antigenic proteins. In this study, we generated VLPs (multi-antigen VLPs, TG146) in insect cells co-infected with recombinant baculoviruses presenting IMC, ROP18, and MIC8 of Toxoplasma gondii together with influenza matrix protein 1 (M1) as a core protein. We also generated three VLPs expressing IMC, ROP18, or MIC8 together with M1 for combination VLPs (TG1/TG4/TG6). A total of four kinds of VLPs generated were characterized by TEM. Higher number of VLPs particles per μm2 were observed in multi-antigen VLPs compared to combination VLPs. Mice (BALB/c) were intranasually immunized with multi-antigen VLPs or combination VLPs and challenged with T. gondii tachyzoites (GT1) intraperitoneally. Compared to combination VLPs, multi-antigen VLPs showed significantly higher levels of CD4+ T cell, and germinal center B cell responses with reduced apoptosis responses, resulting in significant reduction on parasite burden. These results indicate that higher efficacy of VLPs generated by multi-antigen VLPs can induce significant reduction of parasite burden and better survival of mice than that by combination VLPs, providing important insights into vaccine design strategy for VLPs vaccine expressing multiple antigenic proteins

Accuracy of analytical approaches to thermal response test interpretation

Thermal conductivity obtained via thermal response test (TRT) is one of the essential parameters for the design of shallow geothermal systems, especially a borehole heat exchanger (BHE). During TRT analysis, several factors (e.g., start time of analysis and test duration) could influence the estimated thermal conductivity. In addition, the influence of the factors may be different depending on the characteristics of the borehole and ground. This study investigated the effects of the start time and test duration through numerically generated TRT data under a diversity of environment and BHE information such as the thermal conductivity of grouting and ground. The generated numerical data were analyzed with three analytical approaches having different assumptions about the heat source to interpret the sensitivity of factors in the TRT analysis. By conducting the analytical sensitivity analysis, the importance of determining the appropriate start time and test duration could be emphasized when designing the test