Mautner V, Mackay N
Virology. 1984 Nov;139(1):43-52. doi: 10.1016/0042-6822(84)90328-3.
Overlap recombination has been used as a means of generating intertypic recombinants with crossover sites located within a defined region of the adenovirus genome. Using terminal DNA fragments of adenovirus type 2 and type 5 that overlap within the vicinity of the hexon coding region (51.6-59.7 map units), two different crosses could be studied; in one the overlap entirely encompasses the hexon and there are homologous regions at either side of the overlap where recombination is expected, and in the other only one side of the overlap is capable of sustaining recombination. The overall distribution of crossover sites within the overlap has been determined by restriction endonuclease mapping, and analysed in terms of the extent of homology between Ad2 and Ad5 in this region as defined by the DNA sequences (R. Kinloch, N. Mackay, and V. Mautner (1984). J. Biol. Chem., 259, 6431-6436; G. Akusjärvi, P. Aleström, M. Pettersson, M. Lager, H. Jörnvall, and U. Pettersson (1984). Submitted). Crossovers are found only in regions of relatively high DNA homology, as previously shown for intertypic recombination between temperature-sensitive viruses (M. E. G. Boursnell and V. Mautner (1981). Virology 112, 198-209). The presence of a free DNA end within the heterologous zone is insufficient to overcome the barrier to recombination. In crosses where recombination is confined to a relatively small homologous zone (45.9-53.0 mu) there is no special distribution of crossovers within the interval; no "hot spot" is discernible at the free DNA end, suggesting that a free DNA end is not especially recombinogenic, nor at the junction between the homologous and heterologous zones, suggesting that branch migration up to the heterology does not always occur. A cross designed to furnish evidence for gene conversion gave rise to a "conventional" recombinant with a crossover located within a 21-nucleotide tract of homology.
重叠重组已被用作一种产生型间重组体的方法，其交叉位点位于腺病毒基因组的一个定义区域内。利用腺病毒2型和5型的末端DNA片段，它们在六邻体编码区域（51.6 - 59.7图谱单位）附近重叠，可研究两种不同的杂交；在一种杂交中，重叠完全包含六邻体，并且在重叠的两侧有预期发生重组的同源区域，而在另一种杂交中，只有重叠的一侧能够支持重组。重叠区内交叉位点的总体分布已通过限制性内切酶图谱分析确定，并根据该区域中腺病毒2型和5型之间由DNA序列定义的同源程度进行分析（R. Kinloch、N. Mackay和V. Mautner（1984年）。《生物化学杂志》，259，6431 - 6436；G. Akusjärvi、P. Aleström、M. Pettersson、M. Lager、H. Jörnvall和U. Pettersson（1984年）。已提交）。交叉仅在DNA同源性相对较高的区域中发现，如先前对温度敏感病毒间型间重组所显示的那样（M. E. G. Boursnell和V. Mautner（1981年）。《病毒学》112，198 - 209）。异源区内游离DNA末端的存在不足以克服重组障碍。在重组局限于相对较小同源区（45.9 - 53.0 mu）的杂交中，该区间内交叉没有特殊分布；在游离DNA末端没有可辨别的“热点”，这表明游离DNA末端不是特别具有重组活性，在同源区和异源区之间的交界处也没有，这表明分支迁移到异源区并不总是发生。一个旨在提供基因转换证据的杂交产生了一个“常规”重组体，其交叉位于一个21个核苷酸的同源区段内。
