水稻蜡质基因5’上游区中31bp序列增强基因表达的作用

A 31 bp Fragment Within the 5' Upstream Region of Rice Waxy Gene Enhances Gene Expression

为研究水稻蜡质基因 (Wx) 5’上游区中一个与胚乳核蛋白结合的 31bp序列在基因表达中的作用 ,将一系列包含或不包含此序列的长度不同的Wx启动区与 β 葡萄糖苷酸酶基因 (GUS)编码区连接 ,构建成嵌合质粒。将这些质粒通过农杆菌介导转化水稻幼胚愈伤组织 ,并分化产生转基因植株。分别测定抗性愈伤组织中与转基因植株未成熟种子胚乳中的GUS酶活性。结果表明含有 31bp序列的比不含此序列的Wx启动区使GUS报告基因的表达水平高出 2～

It was reported previously that a 31 bp DNA fragment located at 5' upstream region of rice Wx gene could bind the nuclear proteins extracted from immature seeds of rice plant. To analyze the function of this 31 bp fragment, a series of Wx gene promoter regions with or without the 31 bp fragment were ligated with the coding sequence of GUS gene to construct chimeric plasmids(Fig.1). These constructs were inserted in Ti plasmids and introduced into immature embrogenic calli of rice through Agrobacterium mediated gene transfer system, and a number of transgenic plants were regenerated. The GUS activities in the transformed calli(Fig.2) and the immature seeds of transgenic plants(Fig.3) were determined. The data show that the 31 bp fragment enhances GUS gene expression 2～3 times as high as that of the Wx gene promoter region not including it.