Analysis of differentially expressed proteins in Muscovy duck embryo fibroblasts infected with virulent and attenuated Muscovy duck reovirus by two-dimensional polyacrylamide gel electrophoresis.

Muscovy duck reovirus (MDRV) belongs to the Orthoreovirus genus of the Reoviridae family, which is a significant poultry pathogen leading to high morbidity and mortality in ducklings. However, the pathogenesis of the virus is not well understood. In the present study, two-dimensional (2D) polyacrylamide gel electrophoresis (PAGE) combined with LC-MS-MS was used to identify differentially expressed proteins between Muscovy duck embryo fibroblasts (MDEF) infected with virulent (MV9710 strain) and attenuated (CA strain) MDRV and non-infected MDEFs. A total of 115 abundant protein spots were identified. Of these, 59 of differentially expressed proteins were detected, with functions in metabolism and utilization of carbohydrates and nucleotides, anti-stress, and regulation of immune and cellular process. GO analysis of the identified proteins showed that they belonged to the classes molecular function (141 proteins), cellular component (62 proteins), and biological process (146 proteins). The results were validated by qRT-PCR, which suggests that the analysis method of 2D PAGE combined with LC-MS-MS used in this study is reliable. This study lays a foundation for further investigation of the biology of MDRV infection in MDEF.

Phylogenetic analysis of VP1 gene sequences of waterfowl parvoviruses from the Mainland of China revealed genetic diversity and recombination.

To determine the origin and evolution of goose parvovirus (GPV) and Muscovy duck parvovirus (MDPV) in the Mainland of China, phylogenetic and recombination analyses in the present study were performed on 32 complete VP1 gene sequences from China and other countries. Based on the phylogenetic analysis of the VP1 gene, GPV strains studied here from Mainland China (PRC) could be divided into three genotypes, namely PRC-I, PRC-II and PRC-III. Genotype PRC-I is indigenous to Mainland China. Only one GPV strain from Northeast China was of Genotype PRC-II and was thought to be imported from Europe. Genotype PRC-III, which was the most isolated genotype during 1999-2012, is related to GPVs in Taiwan and has been the predominant pathogen responsible for recent Derzy's disease outbreaks in Mainland China. Current vaccine strains used in Mainland China belong to Genotype PRC-I that is evolutionary distant from Genotypes PRC-II and PRC-III. In comparison, MDPV strains herein from Mainland China are clustered in a single group which is closely related to Taiwanese MDPV strains, and the full-length sequences of the VP1 gene of China MDPVs are phylogenetic closely related to the VP1 sequence of a Hungarian MDPV strain. Moreover, We also found that homologous recombination within VP1 gene plays a role in generating genetic diversity in GPV evolution. The GPV GDFSh from Guangdong Province appears to be the evolutionary product of a recombination event between parental GPV strains GD and B, while the major parent B proved to be a reference strain for virulent European GPVs. Our findings provide valuable information on waterfowl parvoviral evolution in Mainland China.