An Epigenetic Role for Disrupted Paternal Gene Expression in Postzygotic Seed Abortion in Arabidopsis Interspecific Hybrids

作     者：Ryan C. Kirkbride Helen Hong Yu Gyoungju Nah Changqing Zhang Xiaoli Shi Z. Jeffrey Chen 

作者机构：Department of Molecular Biosciences Center for Computational Biology and Bioinformatics and Institute for Cellular and Molecular Biology The University of Texas at Austin Austin TX 78712 USA These authors contributed equally to this article. present address: Department of Plant Science Research Institute of Agriculture and Life Sciences Seoul National University Seou1151-921 South Korea present address: Plants for Human Health Institute North Carolina State University 600 Laureate Way Kannapolis NC 28081 USA present address: Institute of Theoretical Physics Chinese Academy of Sciences PO Box 2735 Beijing 100080 China 

出 版 物：《Molecular Plant》 (分子植物（英文版）)

年 卷 期：2015年第8卷第12期

页      面：1766-1775页

核心收录：

学科分类：0710[理学-生物学] 082803[工学-农业生物环境与能源工程] 08[工学] 0828[工学-农业工程] 080204[工学-车辆工程] 0802[工学-机械工程] 0901[农学-作物学] 0902[农学-园艺学] 

基　　金：supported by grants from the National Science Foundation 

主　　题：epigenetics imprinting paternal gene expression polyploidy hybrid incompatibility seeddevelopment 

摘      要：Interspecific hybrids often increase the levels of heterozygosity and hybrid vigor, but some interspecific hybrid seeds are aborted shortly after fertilization. The mechanism behind this postzygotic seed abortion is poorly understood. Here, we report genome-wide analysis of allelic expression changes in developing siliques and seeds in three F1 interspecific crosses between Arabidopsis thaliana （Col, Ler, or C24） and Arabidopsis arenosa. The majority of maternally expressed genes （MEGs） were shared among all three F1 interspecific crosses, whereas ~90% of 272 paternally expressed genes （PEGs） were found only in one or two F1 crosses, suggesting a role for disrupted paternal gene expression in seed abortion that varies in different crosses. Consistent with this notion, 12 PEGs in the infertile interspecific hybrids matched MEGs in fertile intraspecific hybrids. This disruption of PEGs in the interspecific hybrids was consistent with the upregulation of the genes in the paternal-excess interploidy cross （2X6） between a diploid mother and a hexaploid father, leading to the seed abortion. Moreover, a subset of PEGs in the interspecific crosses were also upregulated in the intraspecific hybrid metlXWT or meaXWT, in which the mutant of MET1 （DNA METHYL TRANSFERASE1） or MEDEA, a Polycomb Repressive Complex2 gene, was used as the maternal parent. These data suggest that maternal epigenetic factors and paternal gene expression play important roles in the postzygotic seed abortion in interspecific hybrids or neo-allopolyploids.