title: EMB1211 is required for normal embryo development and influences chloroplast biogenesis in Arabidopsis.
abstract: Chloroplast biogenesis is tightly linked with embryogenesis and seedling development. A growing body of work has been done on the molecular mechanisms underlying chloroplast development; however, the molecular components involved in chloroplast biogenesis during embryogenesis remain largely uncharacterized. In this paper, we show that an Arabidopsis mutant carrying a T-DNA insertion in a gene encoding a multiple membrane occupation and recognition nexus (MORN)-containing protein exhibits severe defects during embryogenesis, producing abnormal embryos and thereby leading to a lethality of young seedlings. Genetic and microscopic studies reveal that the mutation is allelic to a previously designated Arabidopsis embryo-defective 1211 mutant (emb1211). The emb1211 +/- mutant plants produce approximately 25% of white-colored ovules with abnormal embryos since late globular stage when primary chloroplast biogenesis takes place, while the wild-type plants produce all green ovules. Transmission electron microscopic analysis reveals the absence of normal chloroplast development, both in the mutant embryos and in the mutant seedlings, that contributes to the albinism. The EMB1211 gene is preferentially expressed in developing embryos as revealed in the EMB1211::GUS transgenic plants. Taken together, the data indicate that EMB1211 has an important role during embryogenesis and chloroplast biogenesis in Arabidopsis.
authors.affiliation: Department of Plant Biotechnology, Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
authors.forename: Qiuju
authors.initials: Q
authors.lastname: Liang
authors.forename: Xiaoduo
authors.initials: X
authors.lastname: Lu
authors.forename: Ling
authors.initials: L
authors.lastname: Jiang
authors.forename: Chongying
authors.initials: C
authors.lastname: Wang
authors.forename: Yunliu
authors.initials: Y
authors.lastname: Fan
authors.forename: Chunyi
authors.initials: C
authors.lastname: Zhang
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000196:embryology* / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D002736:Chloroplasts / Q000378:metabolism*; D020090:Chromosome Segregation / Q000235:genetics; D032461:Chromosomes, Plant / Q000235:genetics; D017124:Conserved Sequence / Q000235:genetics; D003433:Crosses, Genetic; D004269:DNA, Bacterial; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D005816:Genetic Complementation Test; D006579:Heterozygote; D006720:Homozygote; D008565:Membrane Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D009154:Mutation / Q000235:genetics; D010641:Phenotype; D012639:Seeds / Q000196:embryology* / Q000235:genetics
chemical_list: D029681:Arabidopsis Proteins; D004269:DNA, Bacterial; C558579:EMB1211 protein, Arabidopsis; D008565:Membrane Proteins; C036483:T-DNA