人巨细胞病毒UL148基因在临床低传代分离株中的多态性研究

Polymorphism analysis of human cytomegalovirus UL148 gene in low passage clinical isolates

目的 研究人巨细胞病毒 (HCMV)UL14 8序列在临床低传代分离株中的多态性。方法 对 38株经荧光定量PCR方法 (Q PCR)检测HCMV DNA为阳性的临床低传代分离株的细胞培养上清液进行HCMVUL14 8全序列PCR扩增 ,并对PCR扩增产物进行序列测定及分析。结果 38株临床低传代分离株有 17株PCR扩增阳性 ,与HCMVToledo株进行序列比较分析 ,17株临床分离株UL14 8开放阅读框架 (ORF)长度均与Toledo株相同。其编码蛋白的氨基酸变异率为 0 3%～ 2 3%。所有分离株均有蛋白翻译后修饰位点的新增或缺失。与Toledo株相比 17株临床分离株UL14 8蛋白质二级结构预测结果均为第 15～ 18位之间由α 螺旋变为 β 折叠。 结论 17株HCMV临床低传代分离株UL14 8基因及其编码产物的氨基酸序列比较保守 ,但仍存在一定程度的多态性。

Objective To investigate the polymorphism of human cytomegalovirus UL148 gene in low passage clinical isolates and to study the relationship between the polymorphism and different pathogenesis of congenital HCMV infection. Methods PCR was performed to amplify the entire HCMV UL148 gene region of 38 clinical isolates,which had been proven containing detectable HCMV-DNA by using FQ-PCR. PCR amplification products were sequenced directly and the sequence data were analysed. Results Seventeen of 38 isolates were amplified successfully. By comparison with Toledo sequence,the length of UL148 ORFs in all 17 clinical isolates was similar to that of Toledo.Amino acid variability rate of UL148 protein was 0.3%～2.3%. There were additional or deleted sites of posttranslational modification of UL148 protein in all clinical isolates. Conclusion All DNA and deduced amino acid sequences of UL148 gene shared great similarity among HCMV clinical strains regardless of their polymorphism.