Kim Hayeon, Cho Myeongji, Son Hyeon S
Department of Biomedical Laboratory Science, Kyungdong University, Wonju, Gangwondo, Korea.
Laboratory of Computational Biology & Bioinformatics, Institute of Public Health and Environment, Graduate School of Public Health, Seoul National University, Seoul, Korea.
Genet Mol Biol. 2020 May 11;43(2):e20190240. doi: 10.1590/1678-4685-GMB-2019-0240.
Rift Valley fever virus (RVFV) is a vector-borne pathogen and is the most widely known virus in the genus Phlebovirus. Since it was first reported, RVFV has spread to western Africa, Egypt and Madagascar from its traditional endemic region, and infections continue to occur in new areas. In this study, we analyzed genomic patterns according to the infection properties of RVFV. Among the four segments of RVFV, the nucleotide composition, overall GC content and the difference of GC composition in the third position of the codons (%GC3) between groups were the largest in the S (NP) segment, showing that more diverse codons were used than in other segments. Furthermore, the results of CAI analysis of the S (NP) segment showed that viruses isolated from regions where no previous infections had been reported had the highest values, indicating greater adaptability to human hosts compared with other viruses. This result suggests that mutations in the S (NP) segment co-evolve with the infected hosts and may lead to expansion of the geographic range. The distinctive codon usage patterns observed in specific genomic regions of a group with similar infection properties may be related to the increasing likelihood of RVFV infections in new areas.
裂谷热病毒（RVFV）是一种媒介传播病原体，是白蛉病毒属中最为人所知的病毒。自首次报道以来，RVFV已从其传统流行地区传播至西非、埃及和马达加斯加，新的地区仍不断出现感染病例。在本研究中，我们根据RVFV的感染特性分析了基因组模式。在RVFV的四个基因片段中，S（NP）片段的核苷酸组成、总体GC含量以及密码子第三位的GC组成差异（%GC3）在各组之间最大，表明该片段使用的密码子比其他片段更多样化。此外，S（NP）片段的CAI分析结果显示，从先前未报告过感染病例的地区分离出的病毒具有最高值，表明与其他病毒相比，这些病毒对人类宿主的适应性更强。这一结果表明，S（NP）片段中的突变与受感染宿主共同进化，可能导致地理范围的扩大。在具有相似感染特性的一组特定基因组区域中观察到的独特密码子使用模式，可能与RVFV在新地区感染可能性的增加有关。
