山东省肠道病毒71型分离株SDLY 01的基因组扩增和特征分析

Objective To amplify the genome sequences of an EV71 strain and understand the genome characteristics of SDLY 01, it will provide a basis for constructing an infectious cDNA clone. Methods Stool specimens were collected from a patient with hand, foot and mouth disease. The virus was isolated in RD cells. The full length genome was amplified in three sessions by one step RT-PCR, and the sequences were analyzed by using DNAstar and MEGA 4 software. Results The full length of SDLY 01 was 7408nt, contained 5′UTR 745nt, 3′UTR 81nt, and the coding region 6582nt, encoding a 2194aa polyprotein。The sequence aligements showed that SDLY 01 had the highest nucleotide homology with the Fuyang strain EU703814. It is 97.2%. In regions of 5′UTR and P1, the nucleotide identities between SDLY 01 and EV71 strains were higher than the control strain G10. However, the SDLY 01 nucleotide sequences exhibited the higher homology to G10 than EV71 strains except C4 subtypes in P2, P3 and 3′UTR regions. The phylogenetic analysis based on VP1 and 3D regions showed that SDLY 01 was located in the branch of C4 subtypes. There was an mutation I263V in 3Dpol by amino acid sequence analysis. Conclusion SDLY 01 belongs to C4 subtype. The mutation I263V in 3Dpol may be related to neurovirulence of EV71. The non-structural genes play an important role in the evolution of EV71.