反转录转座子标记及在作物遗传育种中的应用

反转录转座子通过RNA中间体进行反转录而转座,广泛分布于各种植物基因组中,拷贝数多,异质性高,在种内和种间表现出较高的序列差异性和丰富的插入多态性。针对这些特点,开发出了几种基于反转录转座子的分子标记,如SSAP、RIVPI、RAP、REMAP和RBIP等。由于反转录转座子标记能揭示出丰富的多态性,因而在遗传多样性和系谱研究、遗传连锁图谱构建及性状基因定位等方面得到了应用。随着分离技术的不断改进,获取序列信息更加容易,反转录转座子作为分子标记用于作物遗传育种将具有广阔前景。

Retrotransposon-based Molecular Markers and Their Applications in Crop Genetics and Breeding

Retrotransposons are mobile genetic elements which transpose replicatively through RNA intermediates.They are ubiquitous,present in high copy numbers as highly heterogeneous populations,and show insertional polymorphism both within and between species in plants.These genetic properties allowed retrotransposons to be exploited as molecular markers such as SSAP,IRAP,REMAP,RBIP and RIVP.Because of high level of polymorphism,retrotransposon-based markers were used to study genetic diversity,to establish phylogenies,to generate genetic linkage maps and to identify markers linked to agronomically importantly genes.Recent development of some techniques for isolation of retrotransposon sequences,together with easy access to retrotransposon sequences from the vast amount of genomic sequence information,have provided potentials for applying retrotransposon-based markers in crop genetics and breeding.