关键词： Bats   Arthropods   Virus   Ecology   Evolution   Dicistrovirus   Nodavirus   Tombusvirus   Hepadnavirus   Next-generation sequencing  

摘要： Bats host diverse viruses due to their unique ecology, behavior, and immunology. However, the role of other organisms with which bats interact in nature is understudied as a contributor to bat viral diversity. We discovered five viruses in the blood of fruit bats (Hypsignathus monstrosus) from the Republic of Congo. Of these five viruses, four have phylogenetic and genomic features suggesting an arthropod origin (a dicistrovirus, a nodavirus, and two tombus-like viruses), while the fifth (a hepadnavirus) is clearly of mammalian origin. We also report the parallel discovery of related tombus-like viruses in fig wasps and primitive crane flies from bat habitats, as well as high infection rates of bats with haemosporidian parasites (Hepatocystis sp.). These findings suggest transmission between arthropods and bats, perhaps through ingestion or hyperparasitism (viral infection of bat parasites). Some “bat-associated” viruses may be epidemiologically linked to bats through their ecological associations with invertebrates.

关键词： Nipah virus   bat   Ebola virus   tetherin  

摘要： Ebola virus (EBOV) and Nipah virus (NiV) infection of humans can cause fatal disease and constitutes a public health threat. In contrast, EBOV and NiV infection of fruit bats, the putative (EBOV) or proven (NiV) natural reservoir, is not associated with disease, and it is currently unknown how these animals control the virus. The human interferon (IFN)-stimulated antiviral effector protein tetherin (CD317, BST-2) blocks release of EBOV- and NiV-like particles from cells and is counteracted by the EBOV glycoprotein (GP). In contrast, it is unknown whether fruit bat tetherin restricts virus infection and is susceptible to GP-driven antagonism. Here, we report the sequence of fruit bat tetherin and show that its expression is IFN stimulated and associated with strong antiviral activity. Moreover, we demonstrate that EBOV- GP antagonizes tetherin orthologues of diverse species but fails to efficiently counteract fruit bat tetherin in virus-like particle (VLP) release assays. However, unexpectedly, tetherin was dispensable for robust IFN-mediated inhibition of EBOV spread in fruit bat cells. Thus, the VLP-based model systems mimicking tetherin-mediated inhibition of EBOV release and its counteraction by GP seem not to adequately reflect all aspects of EBOV release from IFN-stimulated fruit bat cells, potentially due to differences in tetherin expression levels that could not be resolved by the present study. In contrast, tetherin expression was essential for IFN-dependent inhibition of NiV infection, demonstrating that IFN-induced fruit bat tetherin exerts antiviral activity and may critically contribute to control of NiV and potentially other highly virulent viruses in infected animals. IMPORTANCE Ebola virus and Nipah virus (EBOV and NiV) can cause fatal disease in humans. In contrast, infected fruit bats do not develop symptoms but can transmit the virus to humans. Why fruit bats but not humans control infection is largely unknown. Tetherin is an antiviral host cell p

关键词： Yokose virus   Bat   China  

摘要： BackgroundYokose virus was first isolated from bats (Miniopterus fuliginosus) collected in Yokosuka, Japan, in 1971, and is a new member of the family Flaviviridae, genus Flavivirus. In this study, we isolated a Yokose virus from a serum sample of Myotis daubentonii (order Chiroptera, family Vespertilionidae) collected in Yunnan province, China in *** serum specimens of bat were used to inoculate in BHK-21 and Vero E6 cells for virus isolation. Then the viral complete genome sequence was obtained and was used for phylogenetic analysis performed by BEAST software *** virus was shown to have cytopathic effects in mammalian cells (BHK-21 and Vero E6). Genome sequencing indicated that it has a single open reading frame (ORF), with a genome of 10,785 nucleotides in total. Phylogenetic analysis of the viral genome suggests that XYBX1332 is a Yokose virus (YOKV) of the genus Flavivirus. Nucleotide and amino acid homology levels of the ORF of XYBX1332 and Oita-36, the original strain of YOKV, were 72 and 82%, respectively. The ORFs of XYBX1332 and Oita-36 encode 3422 and 3425 amino acids, respectively. In addition, the non-coding regions (5- and 3-untranslated regions [UTRs]) of these two strains differ in length and the homology of the 5- and 3-UTRs was 81.5 and 78.3%, *** isolation of YOKV (XYBX1332) from inland China thousands of kilometers from Yokosuka, Japan, suggests that the geographical distribution of YOKV is not limited to the islands of Japan and that it can also exist in the inland areas of Asia. However, there are large differences between the Chinese and Japanese YOKV strains in viral genome.

关键词： Encephalomyocarditis virus (EMCV)   Miniopterus fuliginosus  

摘要： Bats are reservoir hosts of many zoonotic viruses and identification of viruses that they carry is important. This study aimed to use high throughput screening to identify the viruses in fecal guano of Taiwanese insectivorous bats caves in order to obtain more information on bat-derived pathogenic viruses in East Asia. Guano samples were collected from two caves in Taiwan, pooled, and then subjected to Multiplex PCR-based next generation sequencing for viral identification. Subsequently, encephalomyocarditis virus (EMCV) sequence was detected and confirmed by reverse transcription PCR. EMCV is considered as rodent virus and thus, animal species identification through cytochrome oxidase I (COI) barcoding was further done to identify the viral source. Finally, determination of distribution and verification of the presence of EMCV in guano obtained from Japanese and South Korean caves was also done. We concluded that the guano collected was not contaminated with the excrement of rodents which were reported and presumed to live in Taiwan. Also, EMCV genome fragments were found in guanos of Japanese and South Korean caves. It is possible that the eastern bent-wing bat (Miniopterus fuliginosus) is one of the natural hosts of EMCV in East Asia.

关键词： ISG15   Myotis davidii   severe acute respiratory syndrome   papain-like proteases   coronaviruses   interferons  

摘要： Bats have long been observed to be the hosts and the origin of numerous human diseases. Bats, like all mammals, rely on a number of innate immune mechanisms to combat invading pathogens, including the interferon type I, II and III responses. Ubiquitin-like interferon-stimulated gene product 15 (ISG15) is a key modulator of these interferon responses. Within these pathways, ISG15 can serve to stabilize host proteins modulating innate immune responses and act as a cytokine. Post-translational modifications of viral proteins introduced by ISG15 have also been observed to directly affect the function of numerous viral proteins. Unlike ubiquitin, which is virtually identical across all animals, comparison of ISG15s across species reveals that they are relatively divergent, with sequence identity dropping to as low as approximate to 58% among mammals. In addition to serving as an obstacle to the zoonotic transmission of influenza, these ISG15 species-species differences have also long been shown to have an impact on the function of viral deISGylases. Recently, the structure of the first nonhuman ISG15, originating from mouse, suggested that the structures of human ISG15 may not be reflective of other species. Here, the structure of ISG15 from the bat species Myotis davidii solved to 1.37 angstrom resolution is reported. Comparison of this ISG15 structure with those from human and mouse not only underscores the structural impact of ISG15 species-species differences, but also highlights a conserved hydrophobic motif formed between the two domains of ISG15. Using the papain-like deISGylase from Severe acute respiratory syndrome coronavirus as a probe, the biochemical importance of this motif in ISG15-protein engagements was illuminated.

关键词： Immunity   Chiroptera   Immunoglobulins   Leukocyte counts   Trade-off  

摘要： Studies of immunity in bat species are rare. However, it is important to determine immunological variations to identify factors influencing the health status of these endangered mammals from an evolutionary, ecological, conservation, and public health point of view. Immunity is highly variable and can be influenced by both internal (e.g. hormone levels, energy demand) and external factors (e.g. pathogens, climate). As bats have some peculiar ecological, energetic, and putative immunological characteristics, they are outstanding study organisms for ecoimmunological studies. We tested if (i) female bats have a higher immunity than males similar to most other mammalian species and (ii) individuals differ according to their energy demand (e.g. reproductive status). To study these questions, we sampled female and male Myotis daubentonii with different reproductive states and estimated their bacterial killing activity, hemolysis/hemagglutination titer, immunoglobulin G (IgG) concentration, and total and differential white blood cell counts. These methods characterize the cellular and humoral branches of both the adaptive and the innate immune responses of these individuals. Reproductively active males had lower cellular immunity compared to non-reproductive individuals. Pregnant females had increased IgG concentrations while hemolysis was enhanced during lactation. No clear trade-off between immunity and reproduction was found;instead immunity of males and female bats seems to be modulated differently due to varying hormonal and energetic states. Our data suggest that both adaptive and innate immunity as well as individual differences (i.e. sex and reproductive state) need to be considered to get a comprehensive overall picture of immunity in wild mammals. (C) 2018 Deutsche Gesellschaft far Saugetierkunde. Published by Elsevier GmbH. All rights reserved.

关键词： 蝙蝠   蜱虫   宏病毒组学   微小RNA病毒   病毒分离  

摘要： 蝙蝠种类多、分布广,是多种人兽共患病的自然宿主,如严重急性呼吸综合征病毒(Severe acute respiratory syndromes virus)、中东呼吸综合征病毒(Middle-east respiratory syndromes vius)、尼帕病毒(Nipah virus)、狂犬病毒(Rabies virus)及埃博拉病毒(Ebola virus)等。广西因独特的地理位置具有十分丰富蝙蝠资源,但该地区蝙蝠的种类、分布及携带的病毒多样性等还不完全清楚。本研究利用形态学和分子生物学方法,对在桂林、柳州、河池等地区的18个县、区采集到的617只蝙蝠样品进行分类和鉴定。结果鉴定出12种蝙蝠,分别为大蹄蝠(Hipposideros armiger)、中蹄蝠(Hipposidero larvatus灰蹄蝠(Hipposideros cineraceus)、果树蹄蝠(Hipposiderospomona)、普氏蹄蝠(Hipposideros partti)、皮氏菊头蝠(Rhinolophus pearsoni)、托氏菊头蝠(Rhinolophus thomasi)、大耳菊头蝠(Rhinolophus macrotis)、小菊头蝠(Rhinolophus pusillus)、普通长翼蝠(Minipopterus schreibersii)、小黄蝠(Scotophilus kuhlii)和南长翼蝠(Miniopterus pusillus),其中小黄蝠共有133只(21.5%),果树蹄蝠132只(21.4%),中蹄蝠129只(20.9%),其他蝙蝠数量在1-51只之间不等。应用高通量测序技术(High-throughput sequencing,HTS)对这些蝙蝠的肠道组织开展宏病毒组学研究。结果共得到89825条reads注释到病毒序列,其中有37426条(41.7%)reads与噬菌体相关,49828条(55.47%)与真核生物病毒相关,另外还有2571条(2.8%)reads未注释到已知病毒序列。与真核生物相关的病毒序列,主要涉及副黏病毒科(Paramyxoviridae)、弹状病毒科(Rhabdoviridae)、丝状病毒科(Filoviridae)、冠状病毒科(Cornaviridae)、细小病毒科(Parvoviridae)、双顺反子病毒科(Dicistroiridae)、软腐病毒科(Iflaviridae)、小核糖核酸病毒科(Picornaviridae)、星状病毒科(Astroviridae)、杆状病毒科(Baculoviridae)和嗜肝病毒科(Hepadnaviridae)等30多个病毒科。其中脊椎动物病毒有51种,主要有蝙蝠冠状病毒(Bat coronavirus)、蝙蝠星状病毒(Bat astrovirus)、蝙蝠嗜肝病毒(Bat hepatitis B virus)、甲型肝炎病毒(Hepatitis A virus)和人双埃柯病毒(Human parechovirus)等。昆虫病毒有18种,主要为茶尺蠖病毒(Ectropis obiqua virus)和直尺蠖病毒(Perina nuda virus)。植物病毒主要为斐济病毒属(Fijvirus)的斐济病毒(Fijivirus)。噬菌体主要是一些肠道细菌的噬菌体,涉及基尾噬菌体科(Myoviridae)、短尾噬菌体科(Podoviridae)、长尾噬菌体科(Siphoviridae)、丝状噬菌体科(Inoviridae)、微小噬菌体科(Microviridae)和光滑噬菌体科(Leviviridae)。将这些脊椎动物病毒相关的reads进行组装后,得到485条Contigs,比对发现共有342条(75%)Contigs能够比对到NCBI数据库中已知的病毒序列。基于这些序列信息,进行分析后发现,广西蝙蝠中的蝙蝠星状病毒与已知的蝙蝠星状病毒的差异较大,可能是新的蝙蝠星状病毒;广西的蝙蝠冠状病毒与Bat coronavirus(BtCoV/512/2005)核苷酸相似性为98%,亲缘关系较近;广西蝙蝠中的杯状病毒和嗜肝病毒与已知病毒相似性较高,可能是已知病毒的变异株;广西蝙蝠中的蝙蝠博卡病毒与已知蝙蝠博卡病毒相似性较低,可能是蝙蝠博卡病毒中新的病毒株。利用PCR方法,对广西蝙蝠携带的微小RNA病毒目(Piconrnfaviriales)中的相关病毒进行验证。结果显示广西蝙蝠主要携带七种微小RNA病毒,分别为:甲型肝炎病毒(Hepatovirus A virus)、南蝠微小RNA病毒(Ia io picornavirus)、Shanbavirus、蝙蝠双埃柯病毒(Bat parechovirus)、直尺蠖小RNA样病毒(Perina nuda picorna-