在Arabidopsis中复制的逆转换爆发
Sayuri Tsukahara1, Akie Kobayashi, Akira Kawabe
1Department of Integrated Genetics, National Institute of Genetics, Yata 1111, Mishima, Shizuoka 411-8540, Japan.
Nature
|September 8, 2009
概括
植物基因组含有大量的逆转移体. 使用Arabidopsis thaliana突变物进行的一项研究显示,破坏DNA甲基化 (DDM1) 触发了逆转移素的增殖,模仿了进化基因组动态.
科学领域:
- 遗传学 是一个遗传学.
- 分子生物学分子生物学
- 进化生物学 进化生物学
背景情况:
- 逆转移子是通过RNA复制的移动遗传元素,构成了植物基因组的很大一部分.
- 植物通过长端重复 (LTR) 逆转移体的增殖和删除来动态改变基因组大小和组织.
- 阿拉比多普西斯·塔利亚纳 (Arabidopsis thaliana) 作为研究转子子动态的模型生物,因为它的基因组和表观遗传调节的特征很好.
研究的目的:
- 研究Arabidopsis thaliana内源性LTR逆转移体的调动情况.
- 了解表观遗传变化的影响,特别是DDM1的突变,对转子体活性的影响.
- 探索自然Arabidopsis种群中逆转移体的进化动态.
主要方法:
- 利用遗传和基因组方法,包括高分辨率的基因组阵列.
- 分析了多个自我授粉的ddm1 (DNA甲基化减少1) 突变的线条.
- 在相关的阿拉比多普西斯物种中比较了LTR逆转移素序列.
主要成果:
- 在ddm1突变体中检测到各种逆转移体 (吉普赛,拷贝家族) 和DNA转移体 (突变体家族) 的拷贝数量增加.
- 观察到不同元素的反转换的随机和独立爆发.
- 在天然的阿拉比多普西斯种群中确定了谱系特异性的逆转换突发,主要针对中心重复的重复.
结论:
- DDM1诱导的逆转移素增殖和基因组重组复述了自然的转移素介导的基因组动态.
- 这些发现提供了实验系统来研究控制转子子子活动的分子因素.
- 最近自然种群的逆转换突发有利于更少的基因破坏性基因组位置,例如中心重复.
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