Selection characterization on overlapping reading frame of multiple-protein-encoding P gene in Newcastle disease virus.
The aim of this study was to characterize the molecular evolution of P and V protein genes of the Newcastle disease virus (NDV). The P gene sequences of 55 NDV isolates, representing different chronological and geographic origins, were obtained from GenBank. In this paper, the evolution of the specific regions of the NDV P gene, encoding the P and V proteins, was analyzed. The nucleotides from the shared P/V region encoded the co-amino terminus of the two proteins, while the P-V/V-P region was respectively encoded by the nucleotides within the P ORF or the V ORF in the common sequence (after the mRNA editing site). As well, the P-cut region exclusively encoded the P protein. Finally, the P-V and V-P regions were further broken down into P1 and P2 fragments with the corresponding V1 and V2 fragments. In the P gene, the P-cut portion corresponding to the C-terminal of the P protein was the most highly conserved, while the P-V region was the most variable. This was interpreted as a lower constraint for function in the common sequence than in the unique P sequence that is known to contain an important function. Interestingly, in the common P-V/V-P function, variability of V1 was compensated by a higher conservation of the corresponding P1, and conversely for the P2/V2, which suggested that the flexibility of one ORF with less function served the purpose of allowing positive selection in the other overlapping ORF that exhibited more function.
Liang
Jun-Wen
JW
College of Life Science, Shandong Normal University, Wenhua East Road, Shandong Province, Jinan 250014, China.
Tian
Fu-Lin
FL
Lan
Zhou-Ran
ZR
Huang
Bing
B
Zhuang
Wen-Zhong
WZ
D001483:Base Sequence; D019143:Evolution, Molecular; D014644:Genetic Variation; D009154:Mutation; D009522:Newcastle disease virus / Q000235:genetics*; D012641:Selection, Genetic; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*
D014764:Viral Proteins