L1 retrotransposition is activated by Ten-eleven-translocation protein 1 and repressed by methyl-CpG binding proteins

Zhang, Peng; Ludwig, Anne K.; Hastert, Florian D.; Rausch, Cathia; Lehmkuhl, Anne; Hellmann, Ines; Smets, Martha; Leonhardt, Heinrich and Cardoso, M. Cristina (2017): L1 retrotransposition is activated by Ten-eleven-translocation protein 1 and repressed by methyl-CpG binding proteins. In: Nucleus, Vol. 8, No. 5: pp. 548-562

Abstract

One of the major functions of DNA methylation is the repression of transposable elements, such as the long-interspersed nuclear element 1 (L1). The underlying mechanism(s), however, are unclear. Here, we addressed how retrotransposon activation and mobilization are regulated by methyl-cytosine modifying ten-eleven-translocation (Tet) proteins and how this is modulated by methyl-CpG binding domain (MBD) proteins. We show that Tet1 activates both, endogenous and engineered L1 retrotransposons. Furthermore, we found that Mecp2 and Mbd2 repress Tet1-mediated activation of L1 by preventing 5hmC formation at the L1 promoter. Finally, we demonstrate that the methyl-CpG binding domain, as well as the adjacent non-sequence specific DNA binding domain of Mecp2 are each sufficient to mediate repression of Tet1-induced L1 mobilization. Our study reveals a mechanism how L1 elements get activated in the absence of Mecp2 and suggests that Tet1 may contribute to Mecp2/Mbd2-deficiency phenotypes, such as the Rett syndrome. We propose that the balance between methylation reader and eraser/writer controls L1 retrotransposition.

• Item Type: Journal article
• Faculties: Biology > Department Biology II
• Subjects: 500 Science > 570 Life sciences; biology
• ISSN: 1949-1034
• Language: English