Rice ABERRANT PANICLE ORGANIZATION 1, encoding an F-box protein, regulates meristem fate.
Inflorescence architecture is one of the most important agronomical traits. Characterization of rice aberrant panicle organization 1 (apo1) mutants revealed that APO1 positively controls spikelet number by suppressing the precocious conversion of inflorescence meristems to spikelet meristems. In addition, APO1 is associated with the regulation of the plastchron, floral organ identity, and floral determinacy. Phenotypic analyses of apo1 and floral homeotic double mutants demonstrate that APO1 positively regulates class-C floral homeotic genes, but not class-B genes. Molecular studies revealed that APO1 encodes an F-box protein, an ortholog of Arabidopsis UNUSUAL FLORAL ORGAN (UFO), which is a positive regulator of class-B genes. Overexpression of APO1 caused an increase in inflorescence branches and spikelets. As the mutant inflorescences and flowers differed considerably between apo1 and ufo, the functions of APO1 and UFO appear to have diverged during evolution.
Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo 113-8657, Japan.
Kyoko
K
Ikeda
Momoyo
M
Ito
Nobuhiro
N
Nagasawa
Junko
J
Kyozuka
Yasuo
Y
Nagato
D000595:Amino Acid Sequence; D002454:Cell Differentiation; D003001:Cloning, Molecular; D044783:F-Box Proteins / Q000235:genetics / Q000502:physiology*; D035264:Flowers / Q000235:genetics / Q000254:growth & development; D018506:Gene Expression Regulation, Plant; D005801:Genes, Homeobox; D018519:Meristem / Q000166:cytology / Q000235:genetics*; D008969:Molecular Sequence Data; D009154:Mutation; D012275:Oryza / Q000166:cytology* / Q000235:genetics / Q000254:growth & development; D010641:Phenotype; D010940:Plant Proteins / Q000235:genetics / Q000502:physiology*; D016415:Sequence Alignment
D044783:F-Box Proteins; D010940:Plant Proteins