Plessis A, Dujon B
Unité de Génétique Moléculaire des Levures (URA 1149 du CNRS), Institut Pasteur, Paris, France.
Gene. 1993 Nov 30;134(1):41-50. doi: 10.1016/0378-1119(93)90172-y.
In yeast, the fate of linear DNA molecules upon transformation is determined by the existence of sequence homology between chromosomes and the ends of the transforming molecule. To understand the mechanism of integration of transforming DNA, we have studied the influence of DNA concentration on the frequency and type of transformants obtained, using either non-replicative or replicative plasmids. In both cases, increasing DNA concentration results in multiple tandem repeats integrated into the chromosome containing the homologous target sequence. When a diploid strain is transformed, multiple tandem repeats occur in only one of the two homologous chromosomes at a time. The frequency distribution of the different types of integrants observed indicates non-independent integration events likely to result from plasmid-plasmid interaction prior to chromosome integration. In addition, our results define the proper conditions for optimized gene targetting or gene rescue experiments.
在酵母中，线性DNA分子转化后的命运由染色体与转化分子末端之间序列同源性的存在所决定。为了理解转化DNA的整合机制，我们使用非复制性质粒或复制性质粒，研究了DNA浓度对所获得转化子频率和类型的影响。在这两种情况下，DNA浓度的增加都会导致多个串联重复序列整合到含有同源靶序列的染色体中。当对二倍体菌株进行转化时，多个串联重复序列一次仅出现在两条同源染色体中的一条上。观察到的不同类型整合子的频率分布表明，非独立整合事件可能是由染色体整合之前的质粒-质粒相互作用导致的。此外，我们的结果确定了优化基因靶向或基因拯救实验的合适条件。
