Yoder J I
Department of Vegetable Crops, University of California-Davis, 95616.
Plant Cell. 1990 Aug;2(8):723-30. doi: 10.1105/tpc.2.8.723.
We have found that the maize transposable element Activator (Ac) can rapidly proliferate when transformed into tomato plants. The fate of transposed Ac elements in self-pollinated progeny of independent transgenic tomato plants was examined by DNA gel blot hybridizations. When a single copy of Ac was introduced into a transformant, the number of copies usually remained low in subsequent generations. In one lineage, however, the number of Ac elements increased from one to more than 15 copies in only two generations. DNA gel blot analyses indicated that the amplified elements were not grossly rearranged. Amplified copies of Ac resided at unique sites in the genome, and segregation analysis indicated that these sites were not tightly linked at one genetic locus. Taken together, these observations indicate that the mechanism of Ac amplification is associated with transposition.
我们发现，玉米转座因子激活子（Ac）转化到番茄植株中时能够快速增殖。通过DNA凝胶印迹杂交分析了独立转基因番茄植株自花授粉后代中转座的Ac元件的命运。当将单个Ac拷贝导入转化体时，在后代中其拷贝数通常保持较低水平。然而，在一个株系中，Ac元件的数量在仅两代中就从一个增加到了超过15个拷贝。DNA凝胶印迹分析表明，扩增的元件没有发生严重重排。扩增的Ac拷贝位于基因组中的独特位点，分离分析表明这些位点在一个基因位点上没有紧密连锁。综上所述，这些观察结果表明Ac扩增机制与转座有关。
