Ahrens C H, Carlson C, Rohrmann G F
Genetics Program, Oregon State University, Corvallis 97331-7301, USA.
Virology. 1995 Jul 10;210(2):372-82. doi: 10.1006/viro.1995.1353.
Using a transient complementation assay for DNA replication of an origin-containing reporter plasmid, a 2.4-kb region (m.u. 48.3-50.1) of the Orgyia pseudotsugata multinucleocapsid nuclear polyhedrosis virus (OpMNPV) genome was identified that contains a gene essential for OpMNPV DNA replication. This region was sequenced and open reading frames were identified. Replication assays using subclones from this region identified a gene called late expression factor 3 (lef-3), as the essential replication gene. Transcriptional mapping using both Northern blot and S1 nuclease protection assays demonstrated that lef-3 was expressed as an early gene with a major transcript of 1.7 kb in length. OpMNPV lef-3 encodes a protein with a predicted molecular weight of 42.6 kDa (373 amino acids) and exhibits 41% amino acid sequence identity with its homolog in the genome of the Autographa californica MNPV. A pattern of amino acids similar to that found in single-stranded DNA binding proteins is present in the amino-terminus of both OpMNPV and AcMNPV LEF-3.
利用含病毒复制起点的报告质粒进行瞬时互补分析以检测病毒DNA复制，鉴定出了黄杉毒蛾多核衣壳核型多角体病毒（OpMNPV）基因组中一个2.4 kb的区域（图距48.3 - 50.1），该区域包含OpMNPV DNA复制所必需的一个基因。对该区域进行测序并鉴定出了开放阅读框。利用该区域的亚克隆进行的复制分析确定了一个名为晚期表达因子3（lef - 3）的基因是必需的复制基因。使用Northern印迹法和S1核酸酶保护分析法进行的转录图谱分析表明，lef - 3作为早期基因表达，主要转录本长度为1.7 kb。OpMNPV lef - 3编码一种预测分子量为42.6 kDa（373个氨基酸）的蛋白质，与苜蓿银纹夜蛾核型多角体病毒（AcMNPV）基因组中的同源蛋白具有41%的氨基酸序列同一性。OpMNPV和AcMNPV LEF - 3的氨基末端都存在一种与单链DNA结合蛋白中发现的氨基酸模式相似的模式。
