Shiroki K, Ohshima K, Fukui Y, Ariga H
J Virol. 1986 Mar;57(3):792-801. doi: 10.1128/JVI.57.3.792-801.1986.
An E1B 58K mutant of adenovirus type 12 (Ad12), dl207, was constructed by the deletion of 852 base pairs in the E1B 58K coding region. The mutant could grow efficiently in 293E1 cells but not in HeLa, KB, or human embryo kidney (HEK) cells. Viral DNA replication of dl207 was not detected in HeLa and KB cells and was seldom detected in HEK cells. Analysis of viral DNA synthesis in vitro showed that the Ad12-DNA-protein complex replicated by using the nuclear extract from Ad12 wild-type (WT)-infected HeLa cells but not by using the nuclear extract from dl207-infected cells. In dl207-infected HeLa and KB cells, early mRNAs were detected, but late mRNAs were not detected. The mutant induced fewer transformed foci than the WT in rat 3Y1 cells. Cells transformed by dl207 could grow efficiently in fluid medium, form colonies in soft agar culture, and induce tumors in rats transplanted with the transformed cells at the same efficiency as WT-transformed cells. Tumors were induced in hamsters injected with WT virions but were not induced in hamsters injected with dl207 virions. The results indicate that the E1B 58K protein is required both for viral DNA replication in productive infection and for initiation of cell transformation, but not for maintenance of the transformed phenotype.
通过缺失E1B 58K编码区的852个碱基对构建了12型腺病毒（Ad12）的E1B 58K突变体dl207。该突变体能够在293E1细胞中高效生长，但不能在HeLa、KB或人胚肾（HEK）细胞中生长。在HeLa和KB细胞中未检测到dl207的病毒DNA复制，在HEK细胞中也很少检测到。体外病毒DNA合成分析表明，Ad12-DNA-蛋白质复合物利用来自Ad12野生型（WT）感染的HeLa细胞的核提取物进行复制，但不利用来自dl207感染细胞的核提取物进行复制。在dl207感染的HeLa和KB细胞中，检测到早期mRNA，但未检测到晚期mRNA。在大鼠3Y1细胞中，该突变体诱导的转化灶比WT少。由dl207转化的细胞能够在液体培养基中高效生长，在软琼脂培养中形成集落，并以与WT转化细胞相同的效率在移植了转化细胞的大鼠中诱导肿瘤。注射WT病毒粒子的仓鼠诱发了肿瘤，但注射dl207病毒粒子的仓鼠未诱发肿瘤。结果表明，E1B 58K蛋白在增殖性感染中对于病毒DNA复制以及细胞转化的起始都是必需的，但对于维持转化表型则不是必需的。
