Hirochika H, Hirochika R
Department of Molecular Biology, National Institute of Agrobiological Resources, Ibaraki, Japan.
Jpn J Genet. 1993 Feb;68(1):35-46. doi: 10.1266/jjg.68.35.
Ty1-copia group retrotransposons were searched for in 35 plant species by amplification of the reverse transcriptase coding region using the polymerase chain reaction. Sequences of the expected size were amplified from all of these plant species, including a liverwort, a horsetail, a bracken, gymnosperms and angiosperms. Sequences of 72 clones from 17 species were determined, all of which showed clear homology to the reverse transcriptase sequence of Ty1-copia type retrotransposons. More than half of the sequences carried stop codons or frame shifts. Twenty three new retrotransposon sequences with no interruption by these mutations were revealed. The mechanisms of the evolution of retrotransposons and accumulation of mutations were discussed.
通过聚合酶链反应扩增逆转录酶编码区,在35种植物中搜索Ty1 - copia类逆转座子。从所有这些植物物种中都扩增出了预期大小的序列,包括一种地钱、一种木贼、一种蕨菜、裸子植物和被子植物。测定了17个物种72个克隆的序列,所有序列都与Ty1 - copia类逆转座子的逆转录酶序列有明显的同源性。超过一半的序列带有终止密码子或移码突变。发现了23个没有这些突变干扰的新逆转座子序列。讨论了逆转座子的进化机制和突变积累。