title: OsFIE2 plays an essential role in the regulation of rice vegetative and reproductive development.
abstract: Polycomb group (PcG) proteins are gene repressors that help to maintain cellular identity during development via chromatin remodeling. Fertilization-independent endosperm (FIE), a member of the PcG complex, operates extensively in plant development, but its role in rice has not been fully investigated to date. We report the isolation and characterization of a PcG member in rice, which was designated OsFIE2 for Oryza sativa Fertilization-Independent Endosperm 2. OsFIE2 is a single-copy gene in the rice genome and shows a universal expression pattern. The OsFIE2 RNAi lines displayed pleiotropic phenotypes in vegetative and reproductive organ generation. In unfertilized lines, endosperm formation could be triggered without embryo formation, which indicates that FIE is indeed involved in the suppression of autonomous endosperm development in rice. Furthermore, lateral root generation was promoted early in the roots of OsFIE2 RNAi lines, whereas the primary root was premature and highly differentiated. As the root tip stem cell differentiated, QHB, the gene required for stem cell maintenance in the quiescent center, was down-regulated. Our data suggest that the OsFIE2-PcG complex is vital for rice reproduction and endosperm formation. Its role in stem cell maintenance suggests that the gene is functionally conserved in plants as well as animals.
authors.affiliation: State Key Laboratory of Hybrid Rice, College of Life Science, Wuhan University, Wuhan, 430072, China.|Laboratory of Brassicaceae, Wuhan Institute of Vegetable Science, Wuhan, 430345, China.
authors.forename: Shisheng
authors.initials: S
authors.lastname: Li
authors.affiliation: State Key Laboratory of Hybrid Rice, College of Life Science, Wuhan University, Wuhan, 430072, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Hybrid Rice, College of Life Science, Wuhan University, Wuhan, 430072, China.
authors.forename: Xiongbo
authors.initials: X
authors.lastname: Peng
authors.affiliation: State Key Laboratory of Hybrid Rice, College of Life Science, Wuhan University, Wuhan, 430072, China.
authors.forename: Quan
authors.initials: Q
authors.lastname: Kuang
authors.affiliation: College of Life Science, Huazhong Agriculture University, Wuhan, 430070, China.
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Huang
authors.affiliation: College of Life Science, Huazhong Agriculture University, Wuhan, 430070, China.
authors.forename: Jialing
authors.initials: J
authors.lastname: Yao
authors.affiliation: State Key Laboratory of Hybrid Rice, College of Life Science, Wuhan University, Wuhan, 430072, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Du
authors.affiliation: State Key Laboratory of Hybrid Rice, College of Life Science, Wuhan University, Wuhan, 430072, China.
authors.forename: Meng-Xiang
authors.initials: MX
authors.lastname: Sun
mesh_terms: D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D015536:Down-Regulation; D056625:Endosperm / Q000254:growth & development; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D058685:Genetic Pleiotropy; D012275:Oryza / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D010641:Phenotype; D063245:Plant Development / Q000235:genetics*; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D018517:Plant Roots / Q000254:growth & development; D063146:Polycomb-Group Proteins / Q000235:genetics* / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D012098:Reproduction; D013234:Stem Cells
chemical_list: D029681:Arabidopsis Proteins; C118816:FIE protein, Arabidopsis; D010940:Plant Proteins; D063146:Polycomb-Group Proteins; D012097:Repressor Proteins
keywords: Polycomb proteins; endosperm; fertilization; root development; stem cell
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