Zubko E, Scutt C, Meyer P
Leeds Institute for Plant Biotechnology and Agriculture (LIBA), Faculty of Biological Sciences, The University of Leeds, Leeds LS2 9JT, United Kingdom.
Nat Biotechnol. 2000 Apr;18(4):442-5. doi: 10.1038/74515.
Recombinant genes conferring resistance to antibiotics or herbicides are widely used as selectable markers in plant transformation. Once transgenic material has been selected, the marker gene is dispensable. We report a novel strategy to remove undesirable parts of a transgene after integration into the tobacco genome. This approach is based on the transfer of a vector containing a NPTII gene flanked by two 352 bp attachment P (attP) regions of bacteriophage lambda, and the identification of somatic tissue with deletion events following intrachromosomal recombination between the attP regions. This system was used to delete a 5.9 kb region from a recombinant vector that had been inserted into two different genomic regions. As the attP system does not require the expression of helper proteins to induce deletion events, or a genetic segregation step to remove recombinase genes, it should provide a useful tool to remove undesirable transgene regions, especially in vegetatively propagated species.
赋予抗生素或除草剂抗性的重组基因在植物转化中被广泛用作选择标记。一旦选择了转基因材料，标记基因就不再需要了。我们报告了一种新策略，可在转基因整合到烟草基因组后去除其不需要的部分。该方法基于转移一个载体，该载体包含一个两侧带有噬菌体λ的两个352 bp附着位点P（attP）区域的NPTII基因，并通过attP区域之间的染色体内重组鉴定发生缺失事件的体细胞组织。该系统用于从插入两个不同基因组区域的重组载体中删除一个5.9 kb的区域。由于attP系统不需要表达辅助蛋白来诱导缺失事件，也不需要遗传分离步骤来去除重组酶基因，它应该为去除不需要的转基因区域提供一个有用的工具，特别是在无性繁殖物种中。
