Tissue culture adaptation of natural isolates of simian virus 40: changes occur in viral regulatory region but not in carboxy-terminal domain of large T-antigen.
Tissue culture adaptation of natural isolates of simian virus 40: changes occur in viral regulatory region but not in carboxy-terminal domain of large T-antigen.
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猿猴病毒 40 天然分离株的组织培养适应：病毒调节区发生变化，但大 T 抗原的羧基末端结构域不发生变化。
DOI：
10.1099/0022-1317-78-7-1697
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发表时间：
1997
期刊：
影响因子：
--
通讯作者：
Butel,JS
中科院分区：
文献类型：
--
作者：
Lednicky,JA;Butel,JS
猿猴病毒 40 (SV40) 天然分离株的调控区域与实验室适应病毒株的调控区域不同。后者在增强子区域内有一个核苷酸序列重复，该重复因每个菌株而略有不同，而 SV40 的新鲜分离株则缺乏重复，它含有一个“原型”调节区。许多分离株在编码大肿瘤抗原 (T-ag) 羧基末端的 DNA 中也表现出核苷酸差异。为了确定在实验室适应和长期传代过程中是否可以检测到 SV40 基因组这两个区域的遗传变化，使用 PCR、克隆和测序分析对具有超过 25 年详细传代历史的两个实验室毒株（贝勒毒株和 VA45-54）的低传代病毒库存进行了分析。实验室和原型监管区域都存在于低传代库存中。在监管区域重复之后，没有检测到其他变化。 T-ag羧基末端的可变区在组织培养传代中没有发生任何变化，并且可以作为SV40不同菌株的分类学分类的有用位点。含有源自两种 SV40 菌株的单个或重复增强子的克隆基因组在 CV-1 细胞中均可行。通过 SV40 原型菌株在猴细胞中连续传代 14 次来诱导调节区重复的尝试并未成功。结果与 SV40 的组织培养适应相一致，反映了原始样本中预先存在的罕见变异的选择或受感染细胞中罕见调控区重复的产生。
The regulatory region of natural isolates of simian virus 40 (SV40) is different from that of laboratory-adapted strains of the virus. The latter have a nucleotide sequence duplication within the enhancer region which varies slightly with each strain, whereas the duplication is lacking in fresh isolates of SV40, which contain an ‘archetypal’ regulatory region. Many isolates also display nucleotide differences in the DNA encoding the carboxy terminus of large tumour antigen (T-ag). To determine whether genetic changes in these two regions of the SV40 genome were detectable during laboratory adaptation and long-term passage, low-passage virus stocks of two laboratory strains which had detailed passage histories spanning more than 25 years (Baylor strain and VA45-54) were analysed using PCR, cloning and sequencing assays. Both laboratory and archetypal regulatory regions were present in low-passage stocks. Following duplication in the regulatory region, no additional changes were detectable. The variable region at the T-ag carboxy terminus did not undergo any change with tissue culture passage and may serve as a useful site for taxonomic classification of different strains of SV40. Cloned genomes containing single or duplicated enhancers derived from both SV40 strains were viable in CV-1 cells. Attempts to induce regulatory region duplications by 14 serial passages of SV40 archetypal strains in monkey cells were not successful. The results are compatible with tissue culture adaptation of SV40, reflecting either selection of a rare variant pre-existing in the original sample or generation of a rare regulatory region duplication in infected cells.