Abstract:

The Agrobacterium mediated transgenic rice (Oryza sativa L.) population with inserts of maize transposon Activator/Dissociation (Ac/Ds) was investigated. DNA sequences flanking the T_DNA were analyzed with inverse PCR. Results showed that 65.4% of the T_DNA was integrated in different locations of rice genome, and some T_DNA flanking sequences were located on certain chromosomes. A number of T_DNA was found to have inserted into protein coding regions. In order to induce transposition of the inserted Ds elements, 354 crosses of Ac×Ds and Ds×Ac were constructed. The excision frequency of Ds element trans_activated by Ac transposase was 22.7% in the F2 populations, and the transposition was confirmed with analyses of DNA sequences flanking the Ds elements. In addition to the transposition due to “cut_paste" mechanism, Ds can replicate itself and integrate into a new locus, and inaccurate excisions were also found. A proportion of DNA segments flanking the Ds elements showed no homologies to sequences published in GenBank, of which two were registered under the accession numbers AF355153 and AF355770. The strategy of using transposon tagging for rice genomics study was discussed.

!" : ;- 转座系统在水稻转化群体中的转座活性及
转座子插入位点旁侧序列的分析
朱正歌N，W 付亚萍N 肖晗N 胡国成N 斯华敏N 于永红N 孙宗修N!
（N9 中国水稻研究所农业部水稻生物学重点实验室，杭州>NOOO?；
W9 河北师范大学生命科学学院，石家庄OaOON?）
 

摘要： 利用本实验室构建的转D)（D)<B*!$）及-! （-&!!")&*+&"(）的水稻（C%-(+ .+18A+ H9）转化群体，配置了D) g -! 的杂交组合>a^ 个。检测了转基因植株的<1-ED 插入位点右侧旁邻序列，研究了D) ‘ -! 转座系统在水稻转化群体中的转座活性。结果表明，有些转化植株<1-ED 插入位点相同或相距很近，插入位点互不相同的占?a9 ^h。检测到<1-ED 可插入到编码蛋白的基因中。在D) g -! 的:W
代中，-! 因子的转座频率为WW9 Xh。对D) g -! 杂交子代中-! 因子旁侧序列的分析，进一步表明了-! 因子在水稻基因组中的转座活性，除了从原插入位点解离并转座到新的位点之外，还有复制———转座和不完全切离等现象。获得的旁侧序列中，有些序列与F$(M*(4 中的数据没有同源性，目前有W 个-ED 片段在F$(M*(4 登录。探讨了构建转座子水稻突变体库进行水稻功能基因组学研究的策略。
关键词： 转座子D) ‘ -!；转座活性；旁侧序列；水稻

!通讯作者。K1#*&.：j !/(];k#*&.9 ,]9 ]l9 )( m 。