动物基因组定点整合转基因技术研究进展  

Advances in site-specific integration of transgene in animal genome

作　　者：李国玲[1] 钟翠丽[1] 莫健新[1] 全绒 吴珍芳[1,2] 李紫聪[1] 杨化强[1,2] 张献伟[1,2] 

机构地区：[1]华南农业大学动物科学学院国家生猪种业工程技术研究中心,广州510642 [2]广东温氏食品集团股份有限公司,新兴527439

出　　处：《遗传》2017年第2期98-109,共12页Hereditas（Beijing)

基　　金：国家转基因重大专项(编号:2016ZX08006002);粤西"扬帆计划"博士后人才扶持基金资助项目(2015)资助~~

摘　　要：传统转基因技术,如显微注射、转座子、慢病毒转染等将目的基因插入基因组内的整合方式是随机的,这些随机整合对后期转基因动物品系组建和育种带来诸多不利,因此有研究人员提出了定点整合转基因技术。目前该技术的定点整合效率非常低,主要取决于两个方面:一是靶位点产生DNA双链断裂(double-strand break,DSB)的效率;二是断裂后的靶位点与携带同源臂及外源基因的供体质粒发生同源重组的效率,其中同源重组修复(homologous recombination repair,HDR)是基因组定点整合最为依赖的修复机制。靶位点产生DSB后,机体的DNA修复既可能发生HDR,也可能发生非同源末端连接(nonhomologous end joining,NHEJ),并且两者之间存在竞争关系,因此激活HDR或抑制NEHJ都可提高定点整合转基因的效率。本文结合影响定点整合的因素,对提高定点整合效率最新探索方面进行了综述。The traditional transgenic technologies, such as embryo microinjection, transposon-mediated integration, or lentiviral transfection, usually result in random insertions of the foreign DNA into the host genome, which could have various disadvantages in the establishment of transgenic animals. Therefore, a strategy for site-specific integra- tion of a transgene is needed to generate genetically modified animals with accurate and identical genotypes. However the efficiency for site-specific integration of transgene is very low, which is mainly caused by two issues. The firstone is the low efficiency of inducing double-strand break （DSB） at the target site of host genome in the initial process. The second one is the low efficiency of homologous recombination repair （HDR） between the target site and the do- nor plasmid carrying homologous arm and foreign genes. HDR is the most common mechanism for site-specific inte- gration of a transgene. DSBs can stimulate DNA repair mainly by two competitive mechanisms, HDR and nonhomo- logous end joining （NHEJ）. Hence, activation of HDR or inhibition of NHEJ can promote the HDR in the integration processes, thereby optimizing a specific targeting of the transgene. In this review, we summarize the recent advances in strategies for improving the site-specific integration of foreign transgene in transgenic technologies.

关 键 词：同源重组修复 定点整合 CRISPR/Cas9 

分 类 号：Q78[生物学—分子生物学]