Schuller G, Holt S E, Hsu J, Wilson V G
Department of Medical Microbiology and Immunology, College of Medicine, Texas A&M University Health Science Center, College Station 77843.
Virus Res. 1994 Feb;31(2):203-17. doi: 10.1016/0168-1702(94)90004-3.
Twenty-four overlapping restriction fragments spanning the entire bovine papillomavirus type 1 (BPV-1) genome were analyzed by electrophoresis to determine the extent of static DNA bending in the BPV-1 genome. Thirteen of 24 fragments contained static bends. Based on known locations of previously mapped bend loci and the overlapping pattern of these 13 fragments, we estimate that there are 8-11 distinct static bend loci in the BPV-1 genome. The bend loci were not uniformly distributed on the genome and with one exception, were clustered from nucleotides 5816 to 2621 on the BPV-1 map. This portion of the BPV-1 genome contains most of the transcriptional regulatory sequences as well as the origin of replication. The concordance between the genomic distribution of DNA bends and cis-active elements is consistent with the possibility that bent sequences may contribute to the function of at least some of these elements. However, unlike SV40, there was no static bend at that functional origin of replication for BPV-1. The nearest bends to the origin were approximately 120 bp to the 5' side and 300 bp to the 3' side. As both of these bends were outside of the sequences required for origin function, it is unlikely that static bending plays a critical role in BPV-1 replication.
通过电泳分析了覆盖整个牛乳头瘤病毒1型(BPV-1)基因组的24个重叠限制片段,以确定BPV-1基因组中静态DNA弯曲的程度。24个片段中有13个含有静态弯曲。根据先前绘制的弯曲位点的已知位置以及这13个片段的重叠模式,我们估计BPV-1基因组中有8-11个不同的静态弯曲位点。弯曲位点在基因组上并非均匀分布,且除一个位点外,在BPV-1图谱上从核苷酸5816至2621处聚集。BPV-1基因组的这一部分包含大部分转录调控序列以及复制起点。DNA弯曲的基因组分布与顺式活性元件之间的一致性表明,弯曲序列可能至少对其中一些元件的功能有贡献。然而,与SV40不同的是,BPV-1的功能性复制起点处没有静态弯曲。离起点最近的弯曲分别在5'侧约120 bp处和3'侧约300 bp处。由于这两个弯曲都在起点功能所需序列之外,因此静态弯曲在BPV-1复制中不太可能起关键作用。