title: BROTHER OF FT AND TFL1 (BFT) has TFL1-like activity and functions redundantly with TFL1 in inflorescence meristem development in Arabidopsis.
abstract: The FLOWERING LOCUS T (FT)/TERMINAL FLOWER 1 (TFL1) family is a small gene family that encodes important regulators that control flower development in Arabidopsis. Here, we investigated the biological role of the product of BROTHER OF FT AND TFL1 (BFT), a member of this family, whose function remains unknown. Comparison of the critical residues that play a role in distinguishing FT- or TFL1-like activity revealed that BFT is more similar to FT. Similar to FT expression, BFT expression showed a diurnal oscillation pattern, peaking in the evening. In situ hybridization revealed BFT expression in the shoot apical meristem, young leaf and axillary inflorescence meristem. Transgenic plants over-expressing BFT exhibited delayed flowering and severe floral defects (floral indeterminacy and compact inflorescences surrounded by serrate leaves), similar to 35S::TFL1 plants. LEAFY (LFY) and APETALA1 (AP1) expression was significantly reduced in 35S::BFT plants. BFT over-expression failed to rescue the terminal flower phenotype of tfl1 mutants; however, it delayed both terminal flower formation in the primary inflorescence and axillary inflorescence development in the tfl1 mutant background. Consistent with this, the loss-of-function BFT alleles, bft-2 and an BFT RNAi line, accelerated termination of the primary inflorescence and formation of axillary inflorescences in the tfl1 mutant background. Taken together, our results suggest that, despite similarities in the critical residues of BFT and FT, BFT possesses a TFL1-like activity and functions redundantly with TFL1 in inflorescence meristem development, and possibly contributes to the regulation of plant architecture.
authors.affiliation: Creative Research Initiative, School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea.
authors.forename: Seong Jeon
authors.initials: SJ
authors.lastname: Yoo
authors.affiliation: Creative Research Initiative, School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea.
authors.forename: Kyung Sook
authors.initials: KS
authors.lastname: Chung
authors.affiliation: Creative Research Initiative, School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea.
authors.forename: Seung Hye
authors.initials: SH
authors.lastname: Jung
authors.affiliation: Creative Research Initiative, School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea.
authors.forename: So Yeon
authors.initials: SY
authors.lastname: Yoo
authors.affiliation: School of Biological Sciences, Seoul National University, Seoul 151-742, Korea.
authors.forename: Jong Seob
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Creative Research Initiative, School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea.
authors.forename: Ji Hoon
authors.initials: JH
authors.lastname: Ahn
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D056626:Inflorescence / Q000254:growth & development*; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D018519:Meristem / Q000254:growth & development*; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D030821:Plants, Genetically Modified / Q000235:genetics / Q000254:growth & development; D018749:RNA, Plant / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D029681:Arabidopsis Proteins; C568223:BFT protein, Arabidopsis; D008565:Membrane Proteins; D018749:RNA, Plant; C102864:TFL1 protein, Arabidopsis
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