人巨细胞病毒UL131A,UL130,UL128基因在先天感染患儿临床株中的变异

对18株临床低传代分离株和5株未传代的人巨细胞病毒（HCMV）临床标本分别进行HCMV UL131A，UL130，UL128基因全序列PCR扩增，并进行序列测定及分析．对23株HCMV临床株的UL131A，UL130，UL128基因编码区域进行比较，结果显示此3个基因核苷酸及其编码蛋白是高度保守的，3个基因的核苷酸同源性为96．2％，95．8％，96.0％，编码蛋白的同源性为97．2％，96．6％，96．9％．不同临床症状患儿的HCMV UL131A，UL130，UL128基因及其编码蛋白具有相似的结构．临床株HCMV UL130和UL128基因编码蛋白具有趋化因子的相似结构．所有结果表明临床株中的UL131A，UL130，UL128序列的保守性可能与HCMV在上皮细胞的增殖有关，也与HCMV转移到白细胞和树突状细胞相关．HCMV UL130和UL128基因编码蛋白具有趋化因子的相似结构可能与HCMV的感染相关．

Genetic Variability of Human Cytomegalovirus UL131A,UL130,UL128 Genes in Strains from Congenitally Infected Infants

To investigated the relationship between the sequence polymorphism and different signs of human cytomegalovirus(HCMV) disease,PCR was performed to amplify the entired HCMV UL131A,UL130,UL128 genes of eighteen low-passage clinical isolates and five non-passage strains from congenitally infected infants and PCR amplification products were sequenced directly.Comparisons were made between UL131A,UL130,UL128 genes of clinical strains and published sequences of Towne and Merlin strains.Detailed sequence analysis showed that the UL131A,UL130,UL128 genes were highly conserved in all clinical strains.The coding regions of clinical strains were identical in size.The nucleotide and amino acid sequence identities of UL131A,UL130,UL128 genes and their putative proteins among all strains were 96.2%,95.8%,96.0% and 97.2%,96.6%,96.9% respectively.The present study indicated that UL131A,UL130,UL128 genes of clinical strains from infants with different sign of HCMV disease showed similar structure.Sequence comparison indicated that UL130 and UL128 genes encoded chemokine-like protein in clinical strains.The conservation of the UL131A-128 loci is consistent with the conclusion that the three encoded proteins are all essential for growth of HCMV in endothelial cells and virus transfer to leukocytes.The presence of chemokine-like domains in UL130 and UL128 putative proteins suggests that the predicted products may play a role in HCMV infectivity.