The maternally expressed polycomb group gene OsEMF2a is essential for endosperm cellularization and imprinting in rice  

作　　者：Xiaojun Cheng Meiyao Pan Zhiguo E Yong Zhou Baixiao Niu Chen Chen 

机构地区：[1]Jiangsu Key Laboratory of Crop Genetics and Physiology,Key Laboratory of Plant Functional Genomics of the Ministry of Education,Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding,Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops,Agricultural College of Yangzhou University,Yangzhou,China [2]Key Laboratory of Rice Biology,China National Rice Research Institute,Hangzhou,China

出　　处：《Plant Communications》2021年第1期69-84,共16页植物通讯（英文）

基　　金：supported by grants from the National Key R&D Program of China(2016YFD0100902);the National Natural Science Foundation of China(31701392);the Science Fund for Distinguished Young Scholars of Jiangsu Province(BK20180047);the Priority Academic Development of Jiangsu Higher Education Institutions.

摘　　要：Cellularization is a key event in endosperm development.Polycomb group(PcG)genes,such as Fertilization-Independent Seed 2(FIS2),are vital for the syncytium-to-cellularization transition in Arabidopsis plants.In this study,we found that OsEMF2a,a rice homolog of the Arabidopsis PcG gene Embryonic Flower2(EMF2),plays a role similar to that of FIS2 in regard to seed development,although there is limited sequence similarity between the genes.Delayed cellularization was observed in osemf2a,associated with an unusual activation of type I MADS-box genes.The cell cycle was persistently activated in osemf2a caryopses,which was likely caused by cytokinin overproduction.However,the overaccumulation of auxin was not found to be associated with the delayed cellularization.As OsEMF2a is a maternally expressed gene in the endosperm,a paternally inherited functional allele was unable to recover the maternal defects of OsEMF2a.Many imprinted rice genes were deregulated in the defective hybrid seeds of osemf2a(♀)/9311(♂)(m9).The paternal expression bias of some paternally expressed genes was disrupted in m9 due to either the activation of maternal alleles or the repression of paternal alleles.These findings suggest that OsEMF2a-PRC2-mediated H3K27me3 is necessary for endosperm cellularization and genomic imprinting in rice.

关 键 词：ENDOSPERM CELLULARIZATION osemf2a PRC2 genomic imprinting RICE 

分 类 号：S511[农业科学—作物学]