Molecular cloning and nucleotides sequence analysis of G₁ genome segment of hantaan virus Z₁₀ strain

Abstract

The molecular cloning of the G₁ genome segment of the Z₁₀ strain of Hantaan virus and analysis of the first gene data on the currently widely used Hantavirus vaccine strain in China are presented. The G₁ genome segment of Z₁₀ virus was amplified by the method of RT-PCR, and the products were cloned into the pGEM-T vector after identification and purification. The clone was sequenced by Sanger’s dideoxy chain termination method. The 1449 bases of the Z₁₀ G₁ genome segment, and the coding for 483 amino acids were determined. The base compositions for the G₁ segment RNA determined from cDNA sequence information, were 20.6% A, 21.6% G, 18.8% C and 30.0% U. These values are similar to those of the 76/118, Lee and SR virus. As compared to the Z₁₀ G₁ segment, the sequence homology at the nucleotide level is 87% (76/118, type I), 86% (Lee, type I), 86% (Hojo, type I), 67% (R22, type II), and 59% (K22, type III). The Z₁₀ virus G₁ protein amino acid sequence identity with other Hantaan viruses (94–95% homology) was higher than that with Seoul type viruses (77–80%). More amino acid sequence heterogeneity between the Z₁₀ and 76/118 was observed in the N terminal, especially the diverging cluster of ten amino acids at position 84 to 93 of the Z₁₀ virus G₁ protein. Conclusion: (1) The Z₁₀ strain is one of the Hantaan viruses. (2) The important region of the Z₁₀ G₁ segment was conservative. (3) Although substantial divergence of nucleotide sequences of the G₁ genome segment was found between the Z₁₀ strain and other type I Hantaviruses, relatively high amino acid sequence homology was shown among them. Thus, good immune protection could be obtained with the inactivated Meriones unguiculatus kidney cell vaccine against other strains of Hantaviruses.