Akabane virus (AKAV) is a member of the genus Orthobunyavirus, family Peribunyaviridae. In addition to AKAV strains that cause fetal Akabane disease, which is characterized by abortion in ruminants, some AKAV strains cause postnatal infection characterized by nonsuppurative encephalomyelitis in ruminants. Here, we focused on the NSs protein, a virulence factor for most viruses belonging to the genus Orthobunyavirus, and we hypothesized that this protein would act as a neurovirulence factor in AKAV strains causing postnatal encephalomyelitis.
View Article and Find Full Text PDFNewcastle disease caused by highly pathogenic viruses of avian paramyxovirus serotype-1 (APMV-1) is a highly contagious poultry disease. Although a large-scale epidemic of Newcastle disease had occurred in Japan between the 1950s and the 2000s, there have been no outbreaks anywhere since 2010. In addition, there are no reports of epidemiological surveys of APMV-1 in wild birds in Japan in the last 10 years.
View Article and Find Full Text PDFStress granules (SGs) are dynamic structures that store cytosolic messenger ribonucleoproteins. SGs have recently been shown to serve as a platform for activating antiviral innate immunity; however, several pathogenic viruses suppress SG formation to evade innate immunity. In this study, we investigated the relationship between rabies virus (RABV) virulence and SG formation, using viral strains with different levels of virulence.
View Article and Find Full Text PDFTransbound Emerg Dis
September 2022
Environmental water-targeted surveillance of migratory aquatic birds at overwintering sites is potentially one of the most effective approaches for understanding the ecology of avian influenza viruses (AIVs). In this study, we improved the method for AIV isolation from environmental water samples by making a minor modification to our previously reported process. We experimentally demonstrated that the AIV recovery efficiency of the modified method was 10-100-fold higher than that of the original method.
View Article and Find Full Text PDFGenetic analyses of highly pathogenic avian influenza H5 subtype viruses isolated from the Izumi Plain, Japan, revealed cocirculation of 2 genetic groups of clade 2.3.4.
View Article and Find Full Text PDFRabies virus phosphoprotein (P protein) is a multifunctional protein that plays key roles in replication as the polymerase cofactor that binds to the complex of viral genomic RNA and the nucleoprotein (N protein), and in evading the innate immune response by binding to STAT transcription factors. These interactions are mediated by the C-terminal domain of P (PCTD). The colocation of these binding sites in the small globular PCTD raises the question of how these interactions underlying replication and immune evasion, central to viral infection, are coordinated and, potentially, coregulated.
View Article and Find Full Text PDFWe previously reported that the avirulent fixed rabies virus strain Ni-CE induces a clear cytopathic effect in mouse neuroblastoma cells, whereas its virulent progenitor, the Nishigahara strain, does not. Infection with Nishigahara and Ni-CE mutants containing a single amino acid substitution in the matrix protein (M) demonstrated that the amino acid at position 95 of M (M95) is a cytopathic determinant. The characteristics of cell death induced by Ni-CE infection resemble those of apoptosis (rounded and shrunken cells, DNA fragmentation), but the intracellular signalling pathway for this process has not been fully investigated.
View Article and Find Full Text PDFPorcine reproductive and respiratory syndrome (PRRS) is an infectious disease, caused by PRRS virus (PRRSV), that critically affects the swine industry. While the detection of PRRSV genes plays a key role in PRRS control, the PRRSV genome is known to undergo frequent mutation. Nevertheless, primer pairs widely used for the detection of PRRSV genes were designed between 1995 and 2010.
View Article and Find Full Text PDFThis study aimed to detect filarial parasites in blood samples of Japanese black bears (Ursus thibetanus japonicus) collected from Iwate Prefecture, Japan. Positive amplicons were obtained from 26 out of 30 samples by nested PCR targeting 18S ribosomal RNA gene and first internal transcribed spacer regions. DNA sequences of Mansonella sp.
View Article and Find Full Text PDFMicrobiol Resour Announc
September 2020
Akabane virus (AKAV) (genus , family ) is an arthropod-borne virus that causes congenital abnormalities in ruminants. Here, we report the complete genome sequences of two AKAV strains causing nonsuppurative encephalomyelitis in cattle by postnatal infection in Japan.
View Article and Find Full Text PDFThe sika deer (Cervus nippon) is one of the most common species of wildlife in Japan. This study aimed to reveal the prevalence of tick-borne protozoan parasites in wild sika deer living in western Japan. We used nested polymerase chain reaction (PCR) to detect the 18S rRNA gene of tick-borne apicomplexan parasites (Babesia, Theileria, and Hepatozoon spp.
View Article and Find Full Text PDFThe Izumi plain in Kagoshima Prefecture, Japan, is an overwintering site for migratory ducks and endangered cranes. We have surveyed avian influenza viruses (AIVs) in this area since 2012 and isolated low-pathogenic AIVs (LPAIVs) of various subtypes every winter season. H3N8 LPAIVs were isolated during the 2012/13 and 2016/17 seasons, and H4N6 LPAIVs were isolated during the 2012/13 and 2013/14 seasons.
View Article and Find Full Text PDFCryptosporidium parvum and Neospora caninum are common parasites in domesticated cattle worldwide, including in Japan. We carried out a serological survey to detect C. parvum and N.
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