Ustav M, Ustav E, Szymanski P, Stenlund A
Cold Spring Harbor Laboratory, NY 11724.
EMBO J. 1991 Dec;10(13):4321-9. doi: 10.1002/j.1460-2075.1991.tb05010.x.
Expression of the viral polypeptides E1 and E2 is necessary and sufficient for replication of BPV in mouse C127 cells. By providing these factors from heterologous expression vectors we have identified a minimal origin fragment from BPV that contains all the sequences required in cis for replication of BPV in short term replication assays. This same sequence is also required for stable replication in the context of the entire viral genome. The identified region is highly conserved between different papillomaviruses, and is unrelated to the previously identified plasmid maintenance sequences. The minimal ori sequence contains a binding site for the viral polypeptide E1, which we identify as a sequence specific DNA binding protein, but surprisingly, an intact binding site for the viral transactivator E2 at the ori is not required. The isolated origin shows an extended host region for replication and replicates efficiently in both rodent and primate cell lines.
病毒多肽E1和E2的表达对于BPV在小鼠C127细胞中的复制是必需且充分的。通过从异源表达载体提供这些因子，我们从BPV中鉴定出一个最小的起源片段，该片段包含在短期复制试验中BPV复制所需的所有顺式作用序列。在整个病毒基因组的背景下，稳定复制也需要相同的序列。鉴定出的区域在不同的乳头瘤病毒之间高度保守，并且与先前鉴定的质粒维持序列无关。最小的ori序列包含病毒多肽E1的结合位点，我们将其鉴定为序列特异性DNA结合蛋白，但令人惊讶的是，ori处病毒反式激活因子E2的完整结合位点并非必需。分离出的起源显示出一个扩展的复制宿主区域，并且在啮齿动物和灵长类细胞系中均能高效复制。
