Extensive Demethylation of Repetitive Elements During Seed Development Underlies Gene Imprinting

DNA methylation is an epigenetic mark associated with transposable element silencing and gene imprinting in flowering plants and mammals. In plants, imprinting occurs in the endosperm, which nourishes the embryo during seed development. We have profiled Arabidopsis DNA methylation genome-wide in the...

Full description

Bibliographic Details
Main Authors: Gehring, Mary, Bubb, Kerry L., Henikoff, Steven
Other Authors: Massachusetts Institute of Technology. Department of Biology
Format: Article
Language:en_US
Published: American Association for the Advancement of Science (AAAS) 2014
Online Access:http://hdl.handle.net/1721.1/84596
https://orcid.org/0000-0003-2280-1522
Description
Summary:DNA methylation is an epigenetic mark associated with transposable element silencing and gene imprinting in flowering plants and mammals. In plants, imprinting occurs in the endosperm, which nourishes the embryo during seed development. We have profiled Arabidopsis DNA methylation genome-wide in the embryo and endosperm and found that large-scale methylation changes accompany endosperm development and endosperm-specific gene expression. Transposable element fragments are extensively demethylated in the endosperm. We discovered new imprinted genes by the identification of candidates associated with regions of reduced endosperm methylation and preferential expression in endosperm relative to other parts of the plant. These data suggest that imprinting in plants evolved from targeted methylation of transposable element insertions near genic regulatory elements followed by positive selection when the resulting expression change was advantageous.