Sui D, Wu P, Kung H J, Lee L F
USDA-Agricultural Research Service, Avian Disease and Oncology Laboratory, East Lansing, MI 48823, USA.
Virus Res. 1995 May;36(2-3):269-78. doi: 10.1016/0168-1702(94)00114-r.
DNA sequence analysis revealed a gene encoding the Marek's disease virus (MDV) DNA polymerase (pol) within the BamHI-E fragment of the long unique region of the virus genome. Identification is based on an extensive amino acid homology between the MDV open reading frame and the DNA pol (UL30) of the herpes simplex virus. We describe here a 3540-base-pair fragment of the MDV DNA encoding 1180 amino acids with a M(r) of 133,920 daltons as the viral DNA pol gene, with the analysis of transcription and translation. In Northern blot hybridization, a transcript of 4.0 kb was detected in GA-MDV-infected duck embryo fibroblast (DEF) cells. An antiserum was generated in rabbit using TryE-pol fusion protein expressed in E. coli. This antiserum specifically immunoprecipitated a protein of 135 kD from lysates of MDV-GA-infected DEF cells. MDV DNA pol showed extensive homology to five distantly related herpesviruses: equine herpesvirus (EHV), varicella-zoster virus (VZV), herpes simplex virus type 1 (HSV-1), Epstein-Barr virus (EBV), and human cytomegalovirus (HCMV). Comparison of amino acid sequences among the herpesviruses highlights nine highly conserved regions. Three of the conserved regions are in the N-terminus in the 3'-5' exonuclease domains and the remaining six are in the C-terminus in the catalytic domains. The predicted structural characters are in good agreement with the published data on a number of human herpesvirus DNA pol. The identification of MDV DNA pol gene may lead to a better understanding of MDV replication.
DNA序列分析显示，在病毒基因组长期独特区域的BamHI-E片段内存在一个编码马立克氏病病毒（MDV）DNA聚合酶（pol）的基因。鉴定基于MDV开放阅读框与单纯疱疹病毒DNA pol（UL30）之间广泛的氨基酸同源性。我们在此描述了一个3540个碱基对的MDV DNA片段，其编码1180个氨基酸，分子量为133,920道尔顿，作为病毒DNA pol基因，并对其转录和翻译进行了分析。在Northern印迹杂交中，在GA-MDV感染的鸭胚成纤维细胞（DEF）中检测到一个4.0 kb的转录本。使用在大肠杆菌中表达的TryE-pol融合蛋白在兔体内产生了抗血清。该抗血清从MDV-GA感染的DEF细胞裂解物中特异性免疫沉淀出一种135 kD的蛋白质。MDV DNA pol与五种远亲疱疹病毒具有广泛的同源性：马疱疹病毒（EHV）、水痘带状疱疹病毒（VZV）、单纯疱疹病毒1型（HSV-1）、爱泼斯坦-巴尔病毒（EBV）和人巨细胞病毒（HCMV）。疱疹病毒之间氨基酸序列的比较突出了九个高度保守的区域。其中三个保守区域位于3'-5'核酸外切酶结构域的N端，其余六个位于催化结构域的C端。预测的结构特征与已发表的许多人类疱疹病毒DNA pol的数据高度一致。MDV DNA pol基因的鉴定可能有助于更好地理解MDV的复制。
