Molecular variability of the coat protein gene of Potato virus Y from tobacco in China.
Thirty-three tobacco samples showing typical symptoms of Potato virus Y (PVY) infection were obtained from tobacco fields in various regions of China. The results of indirect ELISA confirmed the infection with PVY. All the isolates had a capacity to infect tobacco systemically in greenhouse, causing either of two main symptoms: veinal necrosis and mosaic. The nucleotide and amino acid sequences of the coat protein (CP) gene and protein, respectively, of the isolates were determined. Comparison of the isolates revealed a high conservation of the CP gene with an identity of 83.2%. A phylogenetic tree of 41 Chinese isolates of PVY, based on complete CP gene, showed 3 groups corresponding to the strains PVYNTN (A group), PVYO (C group) and a putative new strain similar to PVYN (B group). The amino acid sequences of complete CP protein of the isolates showed an identity of 87.6%. The highest identity was observed in the C-terminal half of the CP protein, where only 11 amino acid differences could be observed, in contrast to the N-terminal half with 22 differences.
Li
N
N
State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing.
Wang
X
X
Zhou
G
G
Dong
J
J
D000595:Amino Acid Sequence; D000956:Antigens, Viral / Q000032:analysis; D036022:Capsid Proteins / Q000235:genetics*; D002681:China; D004797:Enzyme-Linked Immunosorbent Assay; D008969:Molecular Sequence Data; D010802:Phylogeny; D010935:Plant Diseases / Q000821:virology*; D011110:Polymorphism, Genetic; D017800:Potyvirus / Q000235:genetics* / Q000302:isolation & purification; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D014026:Nicotiana / Q000821:virology*
D000956:Antigens, Viral; D036022:Capsid Proteins