MOSAIC FLORAL ORGANS1, an AGL6-like MADS box gene, regulates floral organ identity and meristem fate in rice.
Floral organ identity and meristem determinacy in plants are controlled by combinations of activities mediated by MADS box genes. AGAMOUS-LIKE6 (AGL6)-like genes are MADS box genes expressed in floral tissues, but their biological functions are mostly unknown. Here, we describe an AGL6-like gene in rice (Oryza sativa), MOSAIC FLORAL ORGANS1 (MFO1/MADS6), that regulates floral organ identity and floral meristem determinacy. In the flower of mfo1 mutants, the identities of palea and lodicule are disturbed, and mosaic organs were observed. Furthermore, the determinacy of the floral meristem was lost, and extra carpels or spikelets developed in mfo1 florets. The expression patterns of floral MADS box genes were disturbed in the mutant florets. Suppression of another rice AGL6-like gene, MADS17, caused no morphological abnormalities in the wild-type background, but it enhanced the phenotype in the mfo1 background, indicating that MADS17 has a minor but redundant function with that of MFO1. Whereas single mutants in either MFO1 or the SEPALLATA-like gene LHS1 showed moderate phenotypes, the mfo1 lhs1 double mutant showed a severe phenotype, including the loss of spikelet meristem determinacy. We propose that rice AGL6-like genes help to control floral organ identity and the establishment and determinacy of the floral meristem redundantly with LHS1.
Ohmori
Shinnosuke
S
Rice Biotechnology Research Subteam (Hokuriku Region), National Agricultural Research Center, National Agriculture and Food Research Organization, Niigata 943-0193, Japan.
Kimizu
Mayumi
M
Sugita
Maiko
M
Miyao
Akio
A
Hirochika
Hirohiko
H
Uchida
Eiji
E
Nagato
Yasuo
Y
Yoshida
Hitoshi
H
D035264:Flowers / Q000166:cytology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D017403:In Situ Hybridization; D026161:MADS Domain Proteins / Q000235:genetics / Q000378:metabolism*; D018519:Meristem / Q000166:cytology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D008969:Molecular Sequence Data; D012275:Oryza / Q000166:cytology / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000166:cytology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*
D026161:MADS Domain Proteins; D010940:Plant Proteins