基因激活标签体系及其在植物功能基因组学研究中的应用

Activation Tagging and the Application in Plant Functional Genomics

利用传统的基因缺失产生的突变体的方法来鉴定基因的功能效率很低,因为对于发育早期的基因特别是配子发育相关的基因以及冗余基因,这种突变体显得无能为力,前者基因纯合突变体导致死亡、而后者由于冗余基因之间的功能互补而不显示任何表型。而通过基因激活标签技术可以获得显性突变体即功能获得型突变体,为研究这类基因的功能提供了一个重要的手段。基因激活标签技术是指含有35S增强子或启动子的T-DNA或转座子若插入基因内,可导致插入突变,引起插入失活突变体的产生;若插入基因附近(上游或下游),则可能激活正常情况下不表达或表达极弱的基因,导致显性功能获得(dominantgain-of-function)性突变。近年来通过T-DNA或转座子介导的方法建立了多种植物的基因激活标签突变体库,在植物基因功能研究中发挥了重要作用,使一些由多个基因或基因家族决定的功能的研究获得突破性进展。就植物基因激活标签技术的原理,特点和创制方法以及在植物生长发育、代谢等一系列方面研究中的应用进行了阐述,并对该技术的发展趋势进行了较为详细的探讨。

The method of the mutants result from loss-of-function is ineffective to assign the genes function, because of early embryonic whose homozygous mutant results in lethality or functional redundancy which are compensated by other genes possessing of the same function. Dominant mutants or Gain-of-function mutants by activation tagging is an important approach for exploring function of this kind of genes. Activation tagging is the T-DNA or transposons harboring the 35S enhancers or promoters, if it inserts in the genes, there will be loss-of-function mutants; if it inserts upstream or downstream to the gene, the gene expression can be increased above normal level and the dominant gain-of-function mutants will be obtained. Activation tagging mutant pools based on T-DNAs and transposons have been established in several kinds of plants and it suggested the important role of the activation tagging in functional genomics and make the important development for the function explored of the gene family. This paper presents the principle, character, create method of activation tagging, its application in study of growth, development, metabolism of plants and the prospects of activation tagging is also inquired .