遗传 ›› 2014, Vol. 36 ›› Issue (12): 1249-1255.doi: 10.3724/SP.J.1005.2014.1249

• 研究报告 • 上一篇    下一篇

水稻基因组上一个Ds切离及其双位点插入行为的分子鉴定

赵丁丁1, 乔中英2, 程孝1, 王建平2, 焦翠翠1, 孙丙耀1   

  1. 1. 苏州大学基础医学与生物科学学院, 苏州 215123;
    2. 苏州市农业科学院作物研究室, 苏州215155
  • 收稿日期:2014-02-10 出版日期:2014-12-20 发布日期:2014-12-20
  • 通讯作者: 孙丙耀, 博士, 副教授, 研究方向:植物发育生物学。E-mail: sunbingyao@suda.edu.cn E-mail:lovence1@126.com
  • 作者简介:赵丁丁, 硕士研究生, 专业方向:植物发育生物学。Tel: 0512-65882833
  • 基金资助:
    苏州市应用基础研究计划项目(编号:SYN201204 )资助

Molecular identification of one event of Ds excision and re-insertion at two loci in rice genome

Dingding Zhao1, Zhongying Qiao2, Xiao Cheng1, Jianping Wang2, Cuicui Jiao1, Bingyao Sun1   

  1. 1. School of Biology & Basic Medical Sciences, Soochow University, Suzhou 215123, China;
    2. Crop Science Research Laboratory, Suzhou Academy of Agricultural Sciences, Suzhou 215155, China
  • Received:2014-02-10 Online:2014-12-20 Published:2014-12-20

摘要: 玉米转座元件Ac/Ds是hAT转座子家族的成员, 导入水稻基因组后具有转座活性, 尽管转座机制还不完全清楚, 但它们通常经保守的非复制型“剪切-粘贴”过程转座。研究表明, 在Ac编码的转座酶作用下, Ds从原位点切离后常优先重新插入到连锁位点。文章利用TAIL-PCR技术从水稻一个Ds插入突变体及其回复突变体中分离Ds侧翼序列, 结合生物信息学分析方法, 对Ds在突变体上插入位点、回复突变体内切离足迹和重新插入位点进行了分子鉴定。结果显示, 突变体中Ds从3号染色体切离后, 在原插入位点残留了8 bp足迹序列(CATCATGA), 引起Ds标记基因外显子和内含子数目增加, 从而影响基因结构。切离后的Ds重新插入回复突变体第2和第6号染色体上, 分别编码烟草胺氨基转移酶和衰老相关蛋白的2个基因的编码区。因此, 典型的“剪切-粘贴”机制不能完全解释Ds的转座行为, Ds转座存在“剪切-复制-粘贴”的特点。

关键词: 水稻, Ds元件, 侧翼序列, 切离足迹, 转座

Abstract: The maize Ac/Ds transposable elements are members of the hAT transposon superfamily, and have stable transpositional activity in transgenic rice plants. Ac/Ds transposable elements are considered to transpose via a conservative non-replicative “cut and paste” model, though their transposition mechanism is not completely understood. Previous studies have shown that Ds preferentially transposes to genetically linked sites after being excised from its original site in the presence of Ac-transposase. In this study, genomic sequences flanking Ds insertions from a Ds-tagged rice mutant and its rever- tant were determined by TAIL-PCR. The Ds insertion site, the excision footprint and the re-insertion sites in the mutant were identified using bioinformatics tool. The results showed that Ds element excised from its original insertion site on chromosome 3 by leaving an 8 bp footprint (CATCATGA), which resulted in exon changes in tagged gene. After the excision, Ds element was re-inserted into the coding sequences of two genes on chromosome 2 and chromosome 6, which encode a nicotianamine aminotransferase and a senescence-associated protein, respectively. The transposition behavior of Ds element in this study could not be fully explained by the "cut and paste" mechanism, while it is likely to transpose in a "cut and copy and paste" way.

Key words: Oryza sativa L., Ds element, flanking sequence, excision footprint, transposition