Publication

Back to overview

The Polycomb group protein MEDEA and the DNA methyltransferase MET1 interact to repress autonomous endosperm development in Arabidopsis.

Type of publication Peer-reviewed
Publikationsform Original article (peer-reviewed)
Author Schmidt Anja, Wöhrmann Heike J P, Raissig Michael T, Arand Julia, Gheyselinck Jacqueline, Gagliardini Valeria, Heichinger Christian, Walter Joern, Grossniklaus Ueli,
Project The Genetic and Molecular Basis of Gametogenesis and Maternal Effects in Arabidopsis
Show all

Original article (peer-reviewed)

Journal The Plant journal : for cell and molecular biology
Volume (Issue) 73(5)
Page(s) 776 - 87
Title of proceedings The Plant journal : for cell and molecular biology
DOI 10.1111/tpj.12070

Open Access

URL http://onlinelibrary.wiley.com/doi/10.1111/tpj.12070/full
Type of Open Access Publisher (Gold Open Access)

Abstract

In flowering plants, double fertilization of the female gametes, the egg and the central cell, initiates seed development to give rise to a diploid embryo and the triploid endosperm. In the absence of fertilization, the FERTILIZATION-INDEPENDENT SEED Polycomb Repressive Complex 2 (FIS-PRC2) represses this developmental process by histone methylation of certain target genes. The FERTILIZATION-INDEPENDENT SEED (FIS) class genes MEDEA (MEA) and FERTILIZATION-INDEPENDENT ENDOSPERM (FIE) encode two of the core components of this complex. In addition, DNA methylation establishes and maintains the repression of gene activity, for instance via DNA METHYLTRANSFERASE1 (MET1), which maintains methylation of symmetric CpG residues. Here, we demonstrate that Arabidopsis MET1 interacts with MEA in vitro and in a yeast two-hybrid assay, similar to the previously identified interaction of the mammalian homologues DNMT1 and EZH2. MET1 and MEA share overlapping expression patterns in reproductive tissues before and after fertilization, a prerequisite for an interaction in vivo. Importantly, a much higher percentage of central cells initiate endosperm development in the absence of fertilization in mea-1/MEA; met1-3/MET1 as compared to mea-1/MEA mutant plants. In addition, DNA methylation at the PHERES1 and MEA loci, imprinted target genes of the FIS-PRC2, was affected in the mea-1 mutant compared with wild-type embryos. In conclusion, our data suggest a mechanistic link between two major epigenetic pathways involved in histone and DNA methylation in plants by physical interaction of MET1 with the FIS-PRC2 core component MEA. This concerted action is relevant for the repression of seed development in the absence of fertilization.
-