Department of Health Science, Graduate School of Health Sciences, Gunma Paz University, Takasaki-shi, Gunma 370-0006, Japan.
Iwate Prefectural Research Institute for Environmental Science and Public Health, Morioka-shi, Iwate 020-0857, Japan.
Viruses. 2023 Jul 1;15(7):1497. doi: 10.3390/v15071497.
To understand the evolution of GII.P6-GII.6 and GII.P7-GII.6 strains, the prevalent human norovirus genotypes, we analysed both the region and gene in globally collected strains using authentic bioinformatics technologies. A common ancestor of the P6- and P7-type region emerged approximately 50 years ago and a common ancestor of the P6- and P7-type gene emerged approximately 110 years ago. Subsequently, the region and gene evolved. Moreover, the evolutionary rates were significantly faster for the P6-type region and gene than for the P7-type region and genes. Large genetic divergence was observed in the P7-type region and gene compared with the P6-type region and gene. The phylodynamics of the region and gene fluctuated after the year 2000. Positive selection sites in VP1 proteins were located in the antigenicity-related protruding 2 domain, and these sites overlapped with conformational epitopes. These results suggest that the GII.6 gene and VP1 proteins evolved uniquely due to recombination between the P6- and P7-type regions in the HuNoV GII.P6-GII.6 and GII.P7-GII.6 virus strains.
为了了解人诺如病毒 GII.P6-GII.6 和 GII.P7-GII.6 两种主要流行株的进化，我们利用真实的生物信息学技术分析了全球采集的病毒株的 区和 基因。结果发现，P6-和 P7-型 区的共同祖先大约出现在 50 年前，而 P6-和 P7-型 基因的共同祖先大约出现在 110 年前。随后， 区和 基因发生了进化。此外，P6 型 区和 基因的进化速度明显快于 P7 型 区和 基因。与 P6 型 区和 基因相比，P7 型 区和 基因发生了较大的遗传分化。 区和 基因的系统发育动力学在 2000 年后发生了波动。VP1 蛋白中的正选择位点位于抗原相关的突出 2 结构域，这些位点与构象表位重叠。这些结果表明，由于 GII.6 基因和 VP1 蛋白在人诺如病毒 GII.P6-GII.6 和 GII.P7-GII.6 病毒株的 P6-和 P7-型 区之间发生了重组，因此它们独特地进化了。
