[Cloning and analysis of full-length genes of a H9N2 subtype avian influenza virus isolated from Guangdong].
Eight full-length genes of an avian influenza virus Chinese isolate of H9N2 subtype, A/Chicken/Guangdong/HL/2006 (H9N2) (abbreviated as Ck/GD/HL/06), were amplified by RT-PCR, including the 5' and 3' non-coding region. All the genes were cloned and sequenced. The phylogenetic analysis results showed the HA gene of Ck/GD/HL/06 was located in the same phylogenetic clade as Dk/HK/Y280/97 (H9N2), while the Dk/HK/Y280/97-like viruses had been predominately isolated from chickens in mainland China. After the analysis of glycosylation sites and receptor-binding sites in the HA, it was shown that the HA of Ck/GD/HL/06 exhibited the common feature of H9 subtype avian influenza virus isolated from China, but the leucine (Leu) residue at the amino acid position 226 indicated the potential of binding with SA alpha,2-6 receptor. The three internal genes of Ck/GD/HL/06 (PB1, PA and NP) had the highest nucleotide identity with A/Viet Nam/1203/2004 (abbreviated A/VN/1203/04) isolate, which was shown to be transmitted from chickens to human and caused lethal infection in human. No analogous H9N2 strains was reported in previous studies. Based on the high similarity of Ck/GD/HL/06 three genes to A/VN/1203/04, it was suggested that the possibility of generating new highly pathogenic H5N1 AIVs by recombination was worthy of our attention. Further studies should be needed for molecular epidemiologic surveillance of H9N2 AIV in the south China for a long time.
Qi
Yan
Y
College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China. 163_qiyan@163.com
Yuan
Run-yu
RY
Zhang
He-nan
HN
Qi
Wen-bao
WB
Shan
Fen
F
Hu
Yue
Y
Li
Xiao-kang
XK
Jiao
Pei-rong
PR
Liao
Ming
M
D000595:Amino Acid Sequence; D000818:Animals; D002645:Chickens; D002681:China; D003001:Cloning, Molecular; D019143:Evolution, Molecular; D005814:Genes, Viral / Q000235:genetics*; D023281:Genomics; D053127:Influenza A Virus, H9N2 Subtype / Q000235:genetics* / Q000302:isolation & purification*; D005585:Influenza in Birds / Q000821:virology*; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics
D014764:Viral Proteins