人巨细胞病毒UL145基因在先天感染患儿临床株中的多态性研究

目的：研究人巨细胞病毒（HCMV）UL145序列在先天感染患儿临床株中的基因多态性，探讨HCMV基因多态性与先天感染引起的不同临床症状之间的关系。方法：对16株临床低传代分离株和15株未传代临床株的HCMV临床标本分别进行UL145全序列PCR扩增，对PCR扩增阳性的31例标本进行序列测定及分析，并且与9株已在GenBank递交的HCMVUL145序列进行比较分析。结果：序列分析结果表明31株HCMV临床株的UL145基因是高度保守的。所有临床株的HCMVUL145开放阅读框架均为393bp，编码蛋白含有130个氨基酸。所有临床株的核苷酸同源率为95．9％～100％，编码蛋白的同源率为97．7％～100％。临床症状不同的患儿其HCMVUL145基因及其编码蛋白具有相似的结构。所有先天感染患儿临床株的UL145编码蛋白具有蛋白激酶C（PKC）磷酸化功能位点和酪蛋白激酶（CK2）磷酸化功能位点。结论：HCMVUL145基因在临床株中是高度保守，未发现其与HCMV先天感染不同临床症状间存在明显的关系。HCMV UL145基因的高度保守性在先天感染中具有重要作用。

Polymorphism of human cytomegalovirus UL145 gene in strains from infants with congenital human cytomegalovirus infection

Objective: To assess the polymorphism of human cytomegalovirus(HCMV) UL145 gene in the clinical strains from infants with congenital HCMV infection,and to explore the relationship between the polymorphism of UL145 gene and different symptoms of congenital HCMV infection.Methods: UL145 gene was amplified by polymerase chain reaction and sequenced in 16 low-passage clinical isolates and 15 non-passage strains from infants with congenital HCMV infection.Nine sequences of UL145 gene previously published in the GenBank were used for sequence comparison.Results: Detailed sequence analysis revealed that UL145 gene was highly conserved at both nucleotide level and amino acid level.The identities in nucleotide and amino acid sequence and putative protein among all clinical strains ranged from 95.9% to 100% and from 97.7% to 100%,respectively.The structures of UL145 gene of the clinical strains from infants with different symptoms were similar.The UL145 protein of the clinical strains were conserved and comprised phosphorylation motif sites for protein kinase C(PKC) and casein kinase 2(CK2).Conclusion: HCMV UL145 gene is highly conserved in the clinical strains,which may play important roles in congenital HCMV infection.The polymorphism of UL145 gene is not related to different symptoms of congenital HCMV infection.