title: Roles of the Polymerase-Associated Protein Genes in Newcastle Disease Virus Virulence.
abstract: The virulence of Newcastle disease virus varies greatly and is determined by multiple genetic factors. In this study, we systematically evaluated the roles of the polymerase-associated (NP, P and L) protein genes in genotype VII NDV virulence after confirming the envelope-associated (F and HN) proteins contributed greatly to NDV virulence. The results revealed that the polymerase-associated protein genes individually had certain effect on virulence, while transfer of these three genes in combination significantly affected the chimeric virus virulence, especially when the L gene was involved. These results indicated that the L protein was a major contributor to NDV virulence when combined with the homologous NP and P proteins. We also investigated viral RNA synthesis using NDV minigenome systems to assess the interaction between the NP, P, and L proteins, which showed that the activity of the polymerase-associated proteins were directly related to viral RNA transcription and replication.
authors.affiliation: Key Laboratory of Animal Epidemiology and Zoonosis, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University Beijing, China.
authors.forename: Xiao-Hui
authors.initials: XH
authors.lastname: Yu
authors.affiliation: Key Laboratory of Animal Epidemiology and Zoonosis, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University Beijing, China.
authors.forename: Jin-Long
authors.initials: JL
authors.lastname: Cheng
authors.affiliation: Key Laboratory of Animal Epidemiology and Zoonosis, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University Beijing, China.
authors.forename: Jia
authors.initials: J
authors.lastname: Xue
authors.affiliation: Key Laboratory of Animal Epidemiology and Zoonosis, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University Beijing, China.
authors.forename: Ji-Hui
authors.initials: JH
authors.lastname: Jin
authors.affiliation: Key Laboratory of Animal Epidemiology and Zoonosis, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University Beijing, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Song
authors.affiliation: Key Laboratory of Animal Epidemiology and Zoonosis, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University Beijing, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Animal Epidemiology and Zoonosis, Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University Beijing, China.
authors.forename: Guo-Zhong
authors.initials: GZ
authors.lastname: Zhang
keywords: Newcastle disease virus; genotype VII; growth kinetics; replication; reverse genetics; virulence