Vernalization treatment induces site-specific DNA hypermethylation at the VERNALIZATION-A1 (VRN-A1) locus in hexaploid winter wheat

BMC Plant Biology

Research Article

Clémentine Vitte¹  Jérôme Enjalbert²  Isabelle Goldringer²  Abdul Rehman Khan²  Agnès Rousselet²  Anne-Charlotte Marsollier² 

[1] UMR de Génétique Végétale, CNRS, F-91190, Gif sur Yvette, France;UMR de Génétique Végétale, INRA, F-91190, Gif sur Yvette, France;

关键词: VRN1;    Vernalization;    DNA methylation;    Non CG methylation;    Winter wheat;    Transposable element;    Triticum aestivum;    Cold;    Intron;    Jorge;    Sumaya;   

DOI  :  10.1186/1471-2229-13-209

 received in 2013-08-01, accepted in 2013-11-25,  发布年份 2013

来源: Springer

【 摘 要 】

BackgroundCertain temperate species require prolonged exposure to low temperature to initiate transition from vegetative growth to flowering, a process known as vernalization. In wheat, winter cultivars require vernalization to initiate flowering, making vernalization requirement a trait of key importance in wheat agronomy. The genetic bases of vernalization response have been largely studied in wheat, leading to the characterization of a regulation pathway that involves the key gene VERNALIZATION1 (VRN1). While previous studies in wheat and barley have revealed the functional role of histone modification in setting VRN1 expression, other mechanisms might also be involved. Here, we were interested in determining whether the cold-induced expression of the wheat VRN-A1 gene is associated with a change in DNA methylation.ResultsWe provide the first DNA methylation analysis of the VRN-A1 gene, and describe the existence of methylation at CG but also at non CG sites. While CG sites show a bell-shape profile typical of gene-body methylation, non CG methylation is restricted to the large (8.5 kb) intron 1, in a region harboring fragments of transposable elements (TEs). Interestingly, cold induces a site-specific hypermethylation at these non CG sites. This increase in DNA methylation is transmitted through mitosis, and is reset to its original level after sexual reproduction.ConclusionsThese results demonstrate that VRN-A1 has a particular DNA methylation pattern, exhibiting rapid shift within the life cycle of a winter wheat plant following exposure to particular environmental conditions. The finding that this shift occurs at non CG sites in a TE-rich region opens interesting questions onto the possible consequences of this type of methylation in gene expression.

【 授权许可】

Unknown   
© Khan et al.; licensee BioMed Central Ltd. 2013. This article is published under license to BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.