title: The AGL6-like gene OsMADS6 regulates floral organ and meristem identities in rice.
abstract: Although AGAMOUS-LIKE6 (AGL6) MADS-box genes are ancient with wide distributions in gymnosperms and angiosperms, their functions remain poorly understood. Here, we show the biological role of the AGL6-like gene, OsMADS6, in specifying floral organ and meristem identities in rice (Oryza sativa L.). OsMADS6 was strongly expressed in the floral meristem at early stages. Subsequently, OsMADS6 transcripts were mainly detectable in paleas, lodicules, carpels and the integument of ovule, as well as in the receptacle. Compared to wild type plants, osmads6 mutants displayed altered palea identity, extra glume-like or mosaic organs, abnormal carpel development and loss of floral meristem determinacy. Strikingly, mutation of a SEPALLATA (SEP)-like gene, OsMADS1 (LHS1), enhanced the defect of osmads6 flowers, and no inner floral organs or glume-like structures were observed in whorls 2 and 3 of osmads1-z osmads6-1 flowers. Furthermore, the osmads1-z osmads6-1 double mutants developed severely indeterminate floral meristems. Our finding, therefore, suggests that the ancient OsMADS6 gene is able to specify "floral state" by determining floral organ and meristem identities in monocot crop rice together with OsMADS1.
authors.affiliation: School of Life Science and Biotechnology, Shanghai Jiaotong University, Shanghai 200240, China.
authors.forename: Haifeng
authors.initials: H
authors.lastname: Li
authors.forename: Wanqi
authors.initials: W
authors.lastname: Liang
authors.forename: Ruidong
authors.initials: R
authors.lastname: Jia
authors.forename: Changsong
authors.initials: C
authors.lastname: Yin
authors.forename: Jie
authors.initials: J
authors.lastname: Zong
authors.forename: Hongzhi
authors.initials: H
authors.lastname: Kong
authors.forename: Dabing
authors.initials: D
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D035264:Flowers / Q000254:growth & development / Q000378:metabolism*; D017343:Genes, Plant; D026161:MADS Domain Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D018519:Meristem / Q000254:growth & development / Q000378:metabolism*; D008969:Molecular Sequence Data; D009154:Mutation; D012275:Oryza / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D056771:Ovule / Q000378:metabolism; D010641:Phenotype; D010802:Phylogeny; D010940:Plant Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*
chemical_list: D026161:MADS Domain Proteins; D010940:Plant Proteins