title: Floral Induction in Arabidopsis by FLOWERING LOCUS T Requires Direct Repression of BLADE-ON-PETIOLE Genes by the Homeodomain Protein PENNYWISE.
abstract: Flowers form on the flanks of the shoot apical meristem (SAM) in response to environmental and endogenous cues. In Arabidopsis (Arabidopsis thaliana), the photoperiodic pathway acts through FLOWERING LOCUS T (FT) to promote floral induction in response to day length. A complex between FT and the basic leucine-zipper transcription factor FD is proposed to form in the SAM, leading to activation of APETALA1 and LEAFY and thereby promoting floral meristem identity. We identified mutations that suppress FT function and recovered a new allele of the homeodomain transcription factor PENNYWISE (PNY). Genetic and molecular analyses showed that ectopic expression of BLADE-ON-PETIOLE1 (BOP1) and BOP2, which encode transcriptional coactivators, in the SAM during vegetative development, confers the late flowering of pny mutants. In wild-type plants, BOP1 and BOP2 are expressed in lateral organs close to boundaries of the SAM, whereas in pny mutants, their expression occurs in the SAM. This ectopic expression lowers FD mRNA levels, reducing responsiveness to FT and impairing activation of APETALA1 and LEAFY. We show that PNY binds to the promoters of BOP1 and BOP2, repressing their transcription. These results demonstrate a direct role for PNY in defining the spatial expression patterns of boundary genes and the significance of this process for floral induction by FT.
authors.affiliation: Max Planck Institute for Plant Breeding Research, D-50829 Cologne, Germany (F.A., M.R.-B., R.M.-G., V.P., K.S., S.J., G.C.); andCologne Center for Genomics (J.A., P.N.), Institute of Human Genetics (J.A.), Center for Molecular Medicine Cologne (P.N.), and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (P.N.), University of Cologne, 50931 Cologne, Germany.
authors.forename: Fernando
authors.identifier: http://orcid.org/0000-0003-4736-8876
authors.initials: F
authors.lastname: Andrés
authors.affiliation: Max Planck Institute for Plant Breeding Research, D-50829 Cologne, Germany (F.A., M.R.-B., R.M.-G., V.P., K.S., S.J., G.C.); andCologne Center for Genomics (J.A., P.N.), Institute of Human Genetics (J.A.), Center for Molecular Medicine Cologne (P.N.), and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (P.N.), University of Cologne, 50931 Cologne, Germany.
authors.forename: Maida
authors.identifier: http://orcid.org/0000-0002-6685-5066
authors.initials: M
authors.lastname: Romera-Branchat
authors.affiliation: Max Planck Institute for Plant Breeding Research, D-50829 Cologne, Germany (F.A., M.R.-B., R.M.-G., V.P., K.S., S.J., G.C.); andCologne Center for Genomics (J.A., P.N.), Institute of Human Genetics (J.A.), Center for Molecular Medicine Cologne (P.N.), and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (P.N.), University of Cologne, 50931 Cologne, Germany.
authors.forename: Rafael
authors.identifier: http://orcid.org/0000-0003-0012-5033
authors.initials: R
authors.lastname: Martínez-Gallegos
authors.affiliation: Max Planck Institute for Plant Breeding Research, D-50829 Cologne, Germany (F.A., M.R.-B., R.M.-G., V.P., K.S., S.J., G.C.); andCologne Center for Genomics (J.A., P.N.), Institute of Human Genetics (J.A.), Center for Molecular Medicine Cologne (P.N.), and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (P.N.), University of Cologne, 50931 Cologne, Germany.
authors.forename: Vipul
authors.initials: V
authors.lastname: Patel
authors.affiliation: Max Planck Institute for Plant Breeding Research, D-50829 Cologne, Germany (F.A., M.R.-B., R.M.-G., V.P., K.S., S.J., G.C.); andCologne Center for Genomics (J.A., P.N.), Institute of Human Genetics (J.A.), Center for Molecular Medicine Cologne (P.N.), and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (P.N.), University of Cologne, 50931 Cologne, Germany.
authors.forename: Korbinian
authors.initials: K
authors.lastname: Schneeberger
authors.affiliation: Max Planck Institute for Plant Breeding Research, D-50829 Cologne, Germany (F.A., M.R.-B., R.M.-G., V.P., K.S., S.J., G.C.); andCologne Center for Genomics (J.A., P.N.), Institute of Human Genetics (J.A.), Center for Molecular Medicine Cologne (P.N.), and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (P.N.), University of Cologne, 50931 Cologne, Germany.
authors.forename: Seonghoe
authors.identifier: http://orcid.org/0000-0001-5018-3480
authors.initials: S
authors.lastname: Jang
authors.affiliation: Max Planck Institute for Plant Breeding Research, D-50829 Cologne, Germany (F.A., M.R.-B., R.M.-G., V.P., K.S., S.J., G.C.); andCologne Center for Genomics (J.A., P.N.), Institute of Human Genetics (J.A.), Center for Molecular Medicine Cologne (P.N.), and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (P.N.), University of Cologne, 50931 Cologne, Germany.
authors.forename: Janine
authors.initials: J
authors.lastname: Altmüller
authors.affiliation: Max Planck Institute for Plant Breeding Research, D-50829 Cologne, Germany (F.A., M.R.-B., R.M.-G., V.P., K.S., S.J., G.C.); andCologne Center for Genomics (J.A., P.N.), Institute of Human Genetics (J.A.), Center for Molecular Medicine Cologne (P.N.), and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (P.N.), University of Cologne, 50931 Cologne, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Nürnberg
authors.affiliation: Max Planck Institute for Plant Breeding Research, D-50829 Cologne, Germany (F.A., M.R.-B., R.M.-G., V.P., K.S., S.J., G.C.); andCologne Center for Genomics (J.A., P.N.), Institute of Human Genetics (J.A.), Center for Molecular Medicine Cologne (P.N.), and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (P.N.), University of Cologne, 50931 Cologne, Germany coupland@mpipz.mpg.de.
authors.forename: George
authors.identifier: http://orcid.org/0000-0001-6988-4172
authors.initials: G
authors.lastname: Coupland
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D035264:Flowers / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D018506:Gene Expression Regulation, Plant; D018398:Homeodomain Proteins / Q000235:genetics; D018519:Meristem / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D009154:Mutation; D018515:Plant Leaves / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D012333:RNA, Messenger / Q000235:genetics; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D012098:Reproduction; D015398:Signal Transduction; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D018398:Homeodomain Proteins; D012333:RNA, Messenger; D012097:Repressor Proteins; D014157:Transcription Factors; C487569:RPL protein, Arabidopsis; C496963:BOP1 protein, Arabidopsis; C506721:BOP2 protein, Arabidopsis; C418905:FT protein, Arabidopsis; C074747:LFY protein, Arabidopsis