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cDuck tembusu virus (DTMUV) is an emerging agent that causes a severe disease in ducks. We report herein the first complete genome sequences of duck tembusu virus strains YY5, ZJ-407, and GH-2, isolated from Shaoxing ducks, breeder ducks, and geese, respectively, in China. The genomes of YY5, ZJ-407, and GH-2 are all 10,990 nucleotides (nt) in length and encode a putative polyprotein of 3,426 amino acids. It is flanked by a 5= and a 3= noncoding region (NCR) of 94 and 618 nt, respectively. Knowledge of the whole sequence of DTMUV will be useful for further studies of the mechanisms of virus replication and pathogenesis. In 2010, a novel infectious agent emerged in China and caused extensive epidemics in egg-laying and breeder ducks. The affected ducks showed a severe drop in egg production and paralysis. We isolated the causative agent, a virus, from affected ducks and determined the partial genome sequence. All of Koch's postulates were fulfilled, including duck trials. The isolated virus is considered to belong to a new genotype of tembusu virus (TMUV) and was designated duck TMUV (DTMUV) (1).To date, the complete genome sequence of DTMUV has not been reported. To provide more information about DTMUV, we determined the entire genome sequences of two duck-origin isolates (YY5 and ZJ-407) and a goose-origin isolate (GH-2).The 5= and 3= ends of the genomes were amplified using 5= and 3= rapid amplification of cDNA ends (RACE) strategies (5). Based on partial genomic sequences obtained (1), the remainder of the sequences were generated by five overlapping cDNA fragments covering each of the entire genomes and were sequenced using an Applied Biosystems (ABI) 3730xl DNA analyzer. Overlapping consensus sequences were assembled using the SeqMan II programs to generate contiguous full-genome sequences.The complete genomes of the three DTMUV strains are 10,990 nucleotides (nt) in length, with an open reading frame (ORF) extending from nt 95 to 10,278 that encodes a putative polyprotein of 3,426 amino acids (aa). Aligning the sequence of the polyprotein with those of other mosquito-borne flaviviruses, we observed the highest aa similarity with those of Bagaza virus (BAGV; 82%), St. Louis encephalitis virus (SLEV; 66%), Ilheus virus (ILHV; 63.7%), West Nile virus (WNV; 63.4%), and Japanese encephalitis virus (JEV; 63.3%). Like that of other mosquitoborne flaviviruses, the polyprotein of DTMUV is processed into three structural proteins and seven nonstructural proteins by the viral or host cell proteases.We analyzed the secondary structures and cyclization between the 5= and 3= noncoding regions (NCRs) of DTMUV the mfold program of Zuker et al. (6). The predicted results showed that the folding pattern of the three DTMUVs was similar to those of other mosquito-borne flaviviruses (2, 3, 4). The organization of conserved sequences (CS) of 3= NCRs is RCS3-CS3-RCS2-CS2-CS1 for DTMUV, which is the same as that of the JEV subgroup but different from that of Ntaya subgroup members BAGV and ILHV, in which there is no RCS2 or RCS3,...

Duck reovirus (DRV) is an typical aquatic bird pathogen belonging to the Orthoreovirus genus of the Reoviridae family. Reovirus causes huge economic losses to the duck industry. Although DRV has been identified and isolated long ago, the responses of Cairna moschata to classical/novel duck reovirus (CDRV/NDRV) infections are largely unknown. To investigate the relationship of pathogenesis and immune response, proteomes of C. moschata liver cells under the C/NDRV infections were analyzed, respectively. In total, 5571 proteins were identified, among which 5015 proteins were quantified. The differential expressed proteins (DEPs) between the control and infected liver cells displayed diverse biological functions and subcellular localizations. Among the DEPs, most of the metabolism-related proteins were down-regulated, suggesting a decrease in the basal metabolisms under C/NDRV infections. Several important factors in the complement, coagulation and fibrinolytic systems were significantly up-regulated by the C/NDRV infections, indicating that the serine protease-mediated innate immune system might play roles in the responses to the C/NDRV infections. Moreover, a number of molecular chaperones were identified, and no significantly changes in their abundances were observed in the liver cells. Our data may give a comprehensive resource for investigating the regulation mechanism involved in the responses of C. moschata to the C/NDRV infections.

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We report the first full-length infectious clone of strain JX/CHA/97 of rabbit hemorrhagic disease virus (RHDV). The transcripts from the full-length cDNA clones were infectious when they were directly injected into rabbits. The sequence of the virus recovered from the rabbits was identical to that of the injected RNA transcripts. The cDNA clone was engineered to contain one silent nucleotide change to create an EcoRV site (A to T at nucleotide 2908). The genetic marker was retained in the recovered progeny virus. The transfection of RNA transcripts into RK-13 cells resulted in the synthesis of viral antigens, indicating that the cDNA clones were replication competent. This stable infectious molecular clone should be an important tool for developing a better understanding of the molecular biology and pathogenesis of RHDV.