piggyBac转座子在哺乳动物中的应用

Application of PiggyBac Transposon in Mammals

转座子(transposon)是存在于生物体基因组中的可移动的DNA片段,能够影响基因的结构和功能,广泛存在于生物演化过程中。转座子通过切离和粘贴机制介导外源基因的插入,是研究基因功能,制备转基因动物及基因治疗的优良载体。目前在哺乳动物中转座活性较高且研究最多的是"睡美人"转座子和piggyBac(PB)转座子。前者是目前临床前基因治疗研究中使用最为广泛的转座子,但存在剂量抑制效应和转座效率低等缺陷。而PB转座子可克服剂量抑制效应,且转座高效,转基因载量大,因此在哺乳动物中的应用越来越广泛。作者就PB转座子的作用机制、影响因素及在哺乳动物中的应用现状等进行报道。

Since the resurrection of Sleeping Beauty（SBll）, piggyBac（PB） is also described to work in mammals. DNA transposons are mobile genetic units identified in many mammals, can change the structures of genome and influence the function of special gene. The exogenous gene can be inserted into a new locus by transposase following a ＇ cut and paste＇ mechanism, so transposons have been widely used as tools to study the gene function, generate transgenic animals, and research gene therapy. Compared with SBll, PB has higher transposition level, no dose inhibition effect, and can carry larger fragments, thus PB has been cared more and more recently. Herein, we describe its mechanism of action, the factors influencing the transgenic effects,and the application in mammals.