RESUMO
Limited sampling means that relatively little is known about the diversity and evolutionary history of mammalian members of the Hepadnaviridae (genus Orthohepadnavirus). An important case in point are shrews, the fourth largest group of mammals, but for which there is limited knowledge on the role they play in viral evolution and emergence. Here, we report the discovery of a novel shrew hepadnavirus. The newly discovered virus, denoted shrew hepatitis B virus (SHBV), is divergent to be considered a new species of Orthohepadnavirus. Phylogenetic analysis revealed that these viruses were usually most closely related to TBHBV (tent-making bat hepatitis B virus), known to be able to infect human hepatocytes, and had a similar genome structure, although SHBV fell in a more basal position in the surface protein phylogeny. In sum, these data suggest that shrews are natural hosts for hepadnaviruses and may have played an important role in their long-term evolution.
Assuntos
Evolução Molecular , Infecções por Hepadnaviridae/veterinária , Infecções por Hepadnaviridae/virologia , Hepadnaviridae/isolamento & purificação , Musaranhos/virologia , Sequência de Aminoácidos , Animais , China , Genoma Viral , Hepadnaviridae/química , Hepadnaviridae/classificação , Hepadnaviridae/genética , Infecções por Hepadnaviridae/transmissão , Hepatócitos/virologia , Humanos , Orthohepadnavirus/classificação , Orthohepadnavirus/genética , Orthohepadnavirus/isolamento & purificação , Filogenia , Alinhamento de Sequência , Musaranhos/classificação , Proteínas Virais/química , Proteínas Virais/genéticaRESUMO
To determine the biodiversity of arenaviruses in China, we captured and screened rodents and shrews in Wenzhou city, Zhejiang province, a locality where hemorrhagic fever diseases are endemic in humans. Accordingly, arenaviruses were detected in 42 of 351 rodents from eight species, and in 12 of 272 Asian house shrews (Suncus murinus), by RT-PCR targeting the L segment. From these, a single arenavirus was successfully isolated in cell culture. The virion particles exhibited a typical arenavirus morphology under transmission electron microscopy. Comparison of the S and L segment sequences revealed high levels of nucleotide (>32.2% and >39.6%) and amino acid (>28.8% and >43.8%) sequence differences from known arenaviruses, suggesting that it represents a novel arenavirus, which we designated Wenzhou virus (WENV). Phylogenetic analysis revealed that all WENV strains harbored by both rodents and Asian house shrews formed a distinct lineage most closely related to Old World arenaviruses.
Assuntos
Arenavirus/isolamento & purificação , Muridae/virologia , Musaranhos/virologia , Animais , Arenavirus/classificação , Arenavirus/genética , China , Genoma Viral , Dados de Sequência Molecular , Filogenia , RatosRESUMO
Recently, many novel hantavirus species carried by insectivore had been found. In order to know whether the insectivore-associated hantaviruses exist in China, Asian house shrew (Suncus murinus) were analyzed for the presence of hantaviruses. 362 Asian house shrews were captured in Wenzhou of Zhejiang province. Hantavirus-specific RNA was detected by RT-PCR in lung tissue samples of six shrews. The complete hantavirus S and M segment sequences and also partial L segment sequences were successfully recovered. Pairwise comparison of the nucleotide and deduced amino acid sequences showed that the newly discovered virus strains are most closely related to Thottapalayam virus (TPMV) isolated from S. murinus in India, with 82.5-84.7% sequence identity at the nucleotide level and 95.0-98.2% at the amino acid level. Corresponding sequences of Imjin virus (MJNV) were more distant and other rodent- and insectivore-associated hantaviruses appeared even less related. Phylogenetic analysis revealed that the new variants formed a distinct lineage within TPMV.