Genome expansion of Arabis alpina linked with retrotransposition and reduced symmetric DNA methylation
Genome expansion of Arabis alpina linked with retrotransposition and reduced symmetric DNA methylation
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DOI：
10.1038/nplants.2014.23
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发表时间：
2015-02
期刊：
影响因子：
18
通讯作者：
Eva-Maria Willing;Vimal Rawat;T. Mandáková;Florian Maumus;G. V. James;K. Nordström;C. Becker;N. Warthm
中科院分区：
文献类型：
--
作者：
Eva-Maria Willing;Vimal Rawat;T. Mandáková;Florian Maumus;G. V. James;K. Nordström;C. Becker;N. Warthm
尽管进化保守的机制沉默转座因子的活动，有激烈的差异，即使在密切相关的植物物种之间的转座因子的丰度。我们进行了从头组装的375 Mb基因组的多年生模式植物，南芥高山。分析这个基因组揭示了持久的和最近的转座因子活动主要由吉普赛人长末端重复反转录转座子驱动，延长了低重组的近着丝粒，并将以前的大常染色质区域转化为重复丰富的近着丝粒区域。这降低了A. alpina与出乎意料的低水平DNA甲基化共同发生。最值得注意的是，对称CG和CHG甲基化的显著减少表明A. alpina与Arabidopsis thaliana比较。系统发育分析表明，甲基化维持机制的某些组成部分可能与A.阿尔卑斯山。
Despite evolutionary conserved mechanisms to silence transposable element activity, there are drastic differences in the abundance of transposable elements even among closely related plant species. We conducted a de novo assembly for the 375 Mb genome of the perennial model plant, Arabis alpina. Analysing this genome revealed long-lasting and recent transposable element activity predominately driven by Gypsy long terminal repeat retrotransposons, which extended the low-recombining pericentromeres and transformed large formerly euchromatic regions into repeat-rich pericentromeric regions. This reduced capacity for long terminal repeat retrotransposon silencing and removal in A. alpina co-occurs with unexpectedly low levels of DNA methylation. Most remarkably, the striking reduction of symmetrical CG and CHG methylation suggests weakened DNA methylation maintenance in A. alpina compared with Arabidopsis thaliana. Phylogenetic analyses indicate a highly dynamic evolution of some components of methylation maintenance machinery that might be related to the unique methylation in A. alpina.