Evolutionary Genetics and Computational Biology Research Unit, Department of Genetics, Faculty of Science, Kasetsart University, Thailand.
Evolutionary Genetics and Computational Biology Research Unit, Department of Genetics, Faculty of Science, Kasetsart University, Thailand; Centre for Advanced Studies in Tropical Natural Resources, National Research University-Kasetsart University, Kasetsart University (CASTNAR, NRU-KU), Thailand.
Virus Res. 2018 Jan 15;244:27-35. doi: 10.1016/j.virusres.2017.10.021. Epub 2017 Nov 8.
Dengue virus serotype 3 (DENV-3) can cause all forms of dengue diseases and is a predominant serotype in many countries. This serotype is classified into five genotypes: I-V. Genotypes I-III have widely spread throughout the world, whereas genotypes IV and V are rare. Despite the impact on the spread of dengue diseases, only a few studies have reported the characteristics of DENV present in mosquito vectors. Hence, this study aimed to identify DENV-3 genotypes and reveal genetic variation of this virus presented in field-caught mosquitoes collected from endemic areas in Thailand during 2011-2015. First, we examined the effectiveness of the E gene sequence on DENV-3 genotyping, with results supporting the use of this gene for genotype identification. Then, we sequenced this gene in ten DENV-3 strains isolated from mosquitoes. The results showed that eight and two samples were genotypes III and V, respectively, and that they are closely related to DENV-3 isolated from Southeast and East Asian samples. The translated E gene sequences showed 25 unique amino acid (AA) residues located at 23 positions. Eight out of 25 residues have different chemical properties compared to the conserved AAs that are distributed across the three domains functioning in virus-host interaction. Hence, our study reports the first DENV-3 genotype V in Thailand, with these viruses potentially influencing both the disease severity and epidemic potential of DENV-3.
登革病毒血清型 3（DENV-3）可引起所有形式的登革热疾病，是许多国家的主要血清型。该血清型分为五个基因型：I-V。基因型 I-III 已广泛传播到世界各地，而基因型 IV 和 V 则很少见。尽管对登革热疾病的传播有影响，但只有少数研究报告了蚊媒中存在的 DENV 的特征。因此，本研究旨在鉴定登革病毒 3 型（DENV-3）的基因型，并揭示 2011 年至 2015 年在泰国流行地区从野外捕获的蚊子中携带的这种病毒的遗传变异。首先，我们检验了 E 基因序列在 DENV-3 基因分型中的有效性，结果支持该基因用于基因型鉴定。然后，我们对从蚊子中分离出的 10 株 DENV-3 株进行了该基因的测序。结果表明，其中 8 个和 2 个样本分别为基因型 III 和 V，它们与从东南亚和东亚样本中分离出的 DENV-3 密切相关。翻译的 E 基因序列显示 23 个位置的 25 个独特氨基酸（AA）残基。与分布在三个功能域中的保守 AA 相比，这 25 个残基中有 8 个具有不同的化学性质，这些残基在病毒-宿主相互作用中起作用。因此，本研究报告了泰国首例 DENV-3 基因型 V，这些病毒可能会影响 DENV-3 的疾病严重程度和流行潜力。
