title: Molecular and functional characterization of broccoli EMBRYONIC FLOWER 2 genes.
abstract: Polycomb group (PcG) proteins regulate major developmental processes in Arabidopsis. EMBRYONIC FLOWER 2 (EMF2), the VEFS domain-containing PcG gene, regulates diverse genetic pathways and is required for vegetative development and plant survival. Despite widespread EMF2-like sequences in plants, little is known about their function other than in Arabidopsis and rice. To study the role of EMF2 in broccoli (Brassica oleracea var. italica cv. Elegance) development, we identified two broccoli EMF2 (BoEMF2) genes with sequence homology to and a similar gene expression pattern to that in Arabidopsis (AtEMF2). Reducing their expression in broccoli resulted in aberrant phenotypes and gene expression patterns. BoEMF2 regulates genes involved in diverse developmental and stress programs similar to AtEMF2 in Arabidopsis. However, BoEMF2 differs from AtEMF2 in the regulation of flower organ identity, cell proliferation and elongation, and death-related genes, which may explain the distinct phenotypes. The expression of BoEMF2.1 in the Arabidopsis emf2 mutant (Rescued emf2) partially rescued the mutant phenotype and restored the gene expression pattern to that of the wild type. Many EMF2-mediated molecular and developmental functions are conserved in broccoli and Arabidopsis. Furthermore, the restored gene expression pattern in Rescued emf2 provides insights into the molecular basis of PcG-mediated growth and development.
authors.affiliation: Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan.
authors.forename: Mao-Sen
authors.initials: MS
authors.lastname: Liu
authors.forename: Long-Fang O
authors.initials: LF
authors.lastname: Chen
authors.forename: Chun-Hung
authors.initials: CH
authors.lastname: Lin
authors.forename: Ying-Mi
authors.initials: YM
authors.lastname: Lai
authors.forename: Jia-Yuan
authors.initials: JY
authors.lastname: Huang
authors.forename: Zinmay Renee
authors.initials: ZR
authors.lastname: Sung
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D001937:Brassica / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D049108:Cell Enlargement; D016386:Chromosome Walking; D032461:Chromosomes, Plant / Q000235:genetics / Q000378:metabolism; D003001:Cloning, Molecular; D035264:Flowers / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D008969:Molecular Sequence Data; D010641:Phenotype; D059828:Plant Cells / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D010957:Plasmids / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D012098:Reproduction; D036226:Seedlings / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D014170:Transformation, Genetic
chemical_list: D029681:Arabidopsis Proteins; C494299:EMF2 protein, Arabidopsis; D012097:Repressor Proteins