Partial conservation of LFY function between rice and Arabidopsis

• Published in: Plant and cell physiology 2003-12, Vol.44 (12), p.1311-1319
• Main Authors: Chujo, A, Zhang, Z, Kishino, H, Shimamoto, K, Kyozuka, J
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; amino acid sequences; Anthirrhinum FLO protein; Antirrhinum majus; Arabidopsis - genetics; Arabidopsis - growth & development; Arabidopsis APETALA 1 protein; Arabidopsis LFY protein; Arabidopsis Proteins - genetics; Arabidopsis Proteins - physiology; Arabidopsis thaliana; Arabiodopsis AGAMOUS protein; Conserved Sequence - genetics; Conserved Sequence - physiology; conserved sequences; flowering; Flowers - genetics; Flowers - growth & development; gene expression; Gene Expression Regulation, Developmental; Gene Expression Regulation, Plant; genetic complementation; Genetic Complementation Test; grain crops; Keywords: Divergence — Flower development — Grass species — LFY/FLO — Phylogeny — RFL; leaves; Molecular Sequence Data; Mutation; Oryza - genetics; Oryza - growth & development; Oryza RFL protein; Oryza sativa; ovules; Phenotype; Phylogeny; Plant Leaves - genetics; Plant Leaves - growth & development; plant morphology; plant proteins; Plant Proteins - genetics; Plant Proteins - physiology; Plants, Genetically Modified; rice; sequence alignment; Sequence Homology, Amino Acid; transcription factors; Transcription Factors - genetics; Transcription Factors - physiology; transgenic plants; vegetative growth
• ISSN: 0032-0781; 1471-9053
• DOI: 10.1093/pcp/pcg155

The LFY/FLO genes encode plant-specific transcription factors and play major roles in the reproductive transition as well as floral development. In this study, we reconstructed the phylogenetic tree of the 49 LFY/FLO homologs from various plant species. The tree clearly shows that the LFY/FLO genes from the eudicots and monocots formed the two monophyletic clusters with very high bootstrap probabilities, respectively. Furthermore, grass LFY/FLO genes have experienced significant acceleration of amino acid replacement rate compared with the eudicot homolog. To test whether grass LFY/FLO genes have a conserved function with those of eudicots, we introduced RFL, a rice LFY homolog, into the Arabidopsis lfy mutant. The RFL gene driven by LFY promoter partially rescued the lfy mutation, suggesting that the functions of LFY and RFL partly overlap. Interestingly, the RFL but not LFY, strongly activated the expression of AP1 and AG, the downstream targets of LFY, even in the vegetative tissues. The LFY::RFL transgenic Arabidopsis plants exhibited abnormal patterns of development such as leaf curling, bushy appearance and the transformation of ovules into carpels. All of the results indicate that both the partial conservation and divergence of LFY function between rice and Arabidopsis.