Mobilization of a plant transposon by expression of the transposon‐encoded anti‐silencing factor. (30th July 2013)

• Record Type: Journal Article
• Authors: Fu, Yu; Kawabe, Akira; Etcheverry, Mathilde; Ito, Tasuku; Toyoda, Atsushi; Fujiyama, Asao; Colot, Vincent; Tarutani, Yoshiaki; Kakutani, Tetsuji
• Is Part Of: EMBO journal. Volume 32:Number 17(2013)
• Page Start: 2407
• Page End: 2417
• Publication Date: 2013-07-30
• Subjects: Molecular biology -- Periodicals; 572.805
• DOI: 10.1038/emboj.2013.169
• Languages: English
• ISSNs: 0261-4189

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <p>Transposable elements (TEs) have a major impact on genome evolution, but they are potentially deleterious, and most of them are silenced by epigenetic mechanisms, such as DNA methylation. Here, we report the characterization of a TE encoding an activity to counteract epigenetic silencing by the host. In <italic>Arabidopsis thaliana</italic>, we identified a mobile copy of the <italic>Mutator</italic>‐like element (<italic>MULE</italic>) with degenerated terminal inverted repeats (TIRs). This TE, named <italic>Hiun</italic> (<italic>Hi</italic>), is silent in wild‐type plants, but it transposes when DNA methylation is abolished. When a <italic>Hi</italic> transgene was introduced into the wild‐type background, it induced excision of the endogenous <italic>Hi</italic> copy, suggesting that <italic>Hi</italic> is the autonomously mobile copy. In addition, the transgene induced loss of DNA methylation and transcriptional activation of the endogenous <italic>Hi</italic>. Most importantly, the <italic>trans</italic>‐activation of <italic>Hi</italic> depends on a <italic>Hi</italic>‐encoded protein different from the conserved transposase. Proteins related to this anti‐silencing factor, which we named VANC, are widespread in the non‐TIR <italic>MULE</italic>s and may have contributed to the recent success of these TEs in natural <italic>Arabidopsis</italic> populations.</p> </abstract>