探讨广州地区人巨细胞病毒(HCMV)临床低传代病毒株UL142基因的序列特征。

选取2014年3月至2015年12月在广州医科大学附属广东省妇儿医院儿科就诊的10例HCMV症状性感染患儿的尿液标本为研究对象。将从HCMV症状性感染患儿尿液标本中分离出的病毒株进行多重PCR鉴定，对UL142基因全序列克隆到pMD18-T载体上扩增并将产物进行测序，将测序结果提交GenBank并与GenBank收录的其他10株HCMV病毒株的UL142基因进行比对分析。

从广州地区HCMV症状性感染患儿尿液中成功分离2株HCMV临床病毒株，分别命名为HCMV D2和D3；克隆测序后由GenBank收录，收录号分别为DQ180384和DQ180370。各HCMV病毒株的UL142基因同源性比对分析发现：UL142基因序列较保守，有69处碱基发生变异，且均为点突变，无插入及缺失突变；编码蛋白的氨基酸残基为306个，序列也较保守，其中28处点突变导致编码氨基酸的改变，其余点突变均未导致编码氨基酸改变。不同HCMV病毒株中UL142基因所编码的氨基酸变异率为0.9%～6.5%。各HCMV病毒株UL142基因编码蛋白的二级结构的氨基酸数目不同，但所有HCMV病毒株UL142基因编码蛋白的等电点均在6.48～8.27。

广州地区HCMV临床低传代病毒株ULl42基因序列及其编码产物的氨基酸序列均较为保守，但仍存在一定的多态性，这提示UL142基因在HCMV感染与致病机制的研究中可能具有重要作用。

To detect UL142 gene sequence characteristics of the clinical low passage human cytomegalovirus (HCMV) isolates in Guangzhou.

From March 2014 to December 2015 at the Guangzhou Medical University Affiliated pediatric clinic of Guangdong women and children's Hospital of 10 cases of symptomatic HCMV infection in children with urine samples as the research object. Identify virus strains isolated from urine samples of children with symptomatic HCMV infection using multiple polymerase chain reaction (PCR), and the whole sequence of UL142 gene was cloned into pMD18-T vector and amplified, the sequencing results were submitted to GenBank, and UL142 gene of the other 10 HCMV isolates in the GenBank were compared and analyzed together.

Two HCMV clinical isolates were successfully isolated from the urine sample of children with symptomatic HCMV infection in Guangzhou, named for HCMV D3 and D2. The GenBank included them after cloning and sequencing, and the included sequences were DQ180370 and DQ180384. Homology comparison analysis showed UL142 gene sequences were more conservative, there were 69 base mutations, and all these 69 base mutations were base substitutions, and no insertion and deletion mutations. There were 306 amino acid residues in the protein coding, sequence and more conservative, of which 28 nucleotide point mutation resulted in the change of amino acids and bases for the rest of the mutation did not cause amino acid changes, different isolates variation rate for 0.9%-6.5%. The number of amino acids in the two stage structure of each isolate was different but the isoelectric points of all the isolated strains were in 6.48-8.27.

UL142 gene sequence and amino acid sequence of the HCMV clinical isolates in Guangzhou are more conservative, but there are still some polymorphism, it suggests that the UL142 gene may play an important role in the progress of HCMV infection and pathogenesis.