Finnegan E J, Lawrence G J, Dennis E S, Ellis J G
CSIRO, Division of Plant Industry, Canberra, ACT, Australia.
Plant Mol Biol. 1993 Jul;22(4):625-33. doi: 10.1007/BF00047403.
The Ac element of maize has been modified by deletion of 537 bases (delta NaeAc) from the untranslated leader of the transposase gene. In a second modification the cauliflower mosaic virus 35S promoter has been inserted into the truncated leader of delta NaeAc, 21 bases upstream of the natural translation start. The activity of these modified elements has been compared with that of the unmodified element in transgenic flax. Deletion of sequences in the untranslated leader only marginally increased transposition in callus while insertion of the 35S promoter enhanced transposition frequency 7-8-fold. Increased transposition correlated with increased transcription of the transposase gene. The presence of a 35S promoter upstream of the transposase gene, but outside the Ac element, also enhanced both transcription and transposition.
玉米的Ac元件已通过从转座酶基因的非翻译前导区缺失537个碱基（ΔNaeAc）进行了修饰。在第二次修饰中，花椰菜花叶病毒35S启动子已被插入到ΔNaeAc的截短前导区，位于天然翻译起始位点上游21个碱基处。已将这些修饰元件的活性与转基因亚麻中未修饰元件的活性进行了比较。非翻译前导区序列的缺失仅略微增加了愈伤组织中的转座，而35S启动子的插入使转座频率提高了7至8倍。转座增加与转座酶基因转录增加相关。转座酶基因上游但在Ac元件之外存在35S启动子也增强了转录和转座。
