title: Flowering Time-Regulated Genes in Maize Include the Transcription Factor ZmMADS1.
abstract: Flowering time (FTi) control is well examined in the long-day plant Arabidopsis (Arabidopsis thaliana), and increasing knowledge is available for the short-day plant rice (Oryza sativa). In contrast, little is known in the day-neutral and agronomically important crop plant maize (Zea mays). To learn more about FTi and to identify novel regulators in this species, we first compared the time points of floral transition of almost 30 maize inbred lines and show that tropical lines exhibit a delay in flowering transition of more than 3 weeks under long-day conditions compared with European flint lines adapted to temperate climate zones. We further analyzed the leaf transcriptomes of four lines that exhibit strong differences in flowering transition to identify new key players of the flowering control network in maize. We found strong differences among regulated genes between these lines and thus assume that the regulation of FTi is very complex in maize. Especially genes encoding MADS box transcriptional regulators are up-regulated in leaves during the meristem transition. ZmMADS1 was selected for functional studies. We demonstrate that it represents a functional ortholog of the central FTi integrator SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 (SOC1) of Arabidopsis. RNA interference-mediated down-regulation of ZmMADS1 resulted in a delay of FTi in maize, while strong overexpression caused an early-flowering phenotype, indicating its role as a flowering activator. Taken together, we report that ZmMADS1 represents a positive FTi regulator that shares an evolutionarily conserved function with SOC1 and may now serve as an ideal stating point to study the integration and variation of FTi pathways also in maize.
authors.affiliation: Cell Biology and Plant Biochemistry, Biochemie-Zentrum Regensburg, University of Regensburg, 93040 Regensburg, Germany (P.A., S.B., L.-Z.Z., M.G., T.D.);Institute of Plant Biochemistry, Heinrich Heine University Düsseldorf, 40225 Duesseldorf, Germany (U.Sc.); andBiochemistry, Department of Biology, University of Erlangen-Nürnberg, 91058 Erlangen, Germany (U.So.).
authors.forename: Philipp
authors.initials: P
authors.lastname: Alter
authors.affiliation: Cell Biology and Plant Biochemistry, Biochemie-Zentrum Regensburg, University of Regensburg, 93040 Regensburg, Germany (P.A., S.B., L.-Z.Z., M.G., T.D.);Institute of Plant Biochemistry, Heinrich Heine University Düsseldorf, 40225 Duesseldorf, Germany (U.Sc.); andBiochemistry, Department of Biology, University of Erlangen-Nürnberg, 91058 Erlangen, Germany (U.So.).
authors.forename: Susanne
authors.initials: S
authors.lastname: Bircheneder
authors.affiliation: Cell Biology and Plant Biochemistry, Biochemie-Zentrum Regensburg, University of Regensburg, 93040 Regensburg, Germany (P.A., S.B., L.-Z.Z., M.G., T.D.);Institute of Plant Biochemistry, Heinrich Heine University Düsseldorf, 40225 Duesseldorf, Germany (U.Sc.); andBiochemistry, Department of Biology, University of Erlangen-Nürnberg, 91058 Erlangen, Germany (U.So.).
authors.forename: Liang-Zi
authors.identifier: 0000-0003-4301-8051
authors.initials: LZ
authors.lastname: Zhou
authors.affiliation: Cell Biology and Plant Biochemistry, Biochemie-Zentrum Regensburg, University of Regensburg, 93040 Regensburg, Germany (P.A., S.B., L.-Z.Z., M.G., T.D.);Institute of Plant Biochemistry, Heinrich Heine University Düsseldorf, 40225 Duesseldorf, Germany (U.Sc.); andBiochemistry, Department of Biology, University of Erlangen-Nürnberg, 91058 Erlangen, Germany (U.So.).
authors.forename: Urte
authors.initials: U
authors.lastname: Schlüter
authors.affiliation: Cell Biology and Plant Biochemistry, Biochemie-Zentrum Regensburg, University of Regensburg, 93040 Regensburg, Germany (P.A., S.B., L.-Z.Z., M.G., T.D.);Institute of Plant Biochemistry, Heinrich Heine University Düsseldorf, 40225 Duesseldorf, Germany (U.Sc.); andBiochemistry, Department of Biology, University of Erlangen-Nürnberg, 91058 Erlangen, Germany (U.So.).
authors.forename: Manfred
authors.initials: M
authors.lastname: Gahrtz
authors.affiliation: Cell Biology and Plant Biochemistry, Biochemie-Zentrum Regensburg, University of Regensburg, 93040 Regensburg, Germany (P.A., S.B., L.-Z.Z., M.G., T.D.);Institute of Plant Biochemistry, Heinrich Heine University Düsseldorf, 40225 Duesseldorf, Germany (U.Sc.); andBiochemistry, Department of Biology, University of Erlangen-Nürnberg, 91058 Erlangen, Germany (U.So.).
authors.forename: Uwe
authors.identifier: 0000-0003-1835-5339
authors.initials: U
authors.lastname: Sonnewald
authors.affiliation: Cell Biology and Plant Biochemistry, Biochemie-Zentrum Regensburg, University of Regensburg, 93040 Regensburg, Germany (P.A., S.B., L.-Z.Z., M.G., T.D.);Institute of Plant Biochemistry, Heinrich Heine University Düsseldorf, 40225 Duesseldorf, Germany (U.Sc.); andBiochemistry, Department of Biology, University of Erlangen-Nürnberg, 91058 Erlangen, Germany (U.So.) thomas.dresselhaus@ur.de.
authors.forename: Thomas
authors.identifier: 0000-0001-6442-4302
authors.initials: T
authors.lastname: Dresselhaus
mesh_terms: D000595:Amino Acid Sequence; D015536:Down-Regulation; D035264:Flowers / Q000235:genetics* / Q000254:growth & development; D020869:Gene Expression Profiling / Q000379:methods; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D026161:MADS Domain Proteins / Q000235:genetics*; D018519:Meristem / Q000235:genetics / Q000254:growth & development; D018613:Microscopy, Confocal; D017440:Photoperiod; D018515:Plant Leaves / Q000235:genetics / Q000254:growth & development; D010940:Plant Proteins / Q000235:genetics*; D030821:Plants, Genetically Modified; D034622:RNA Interference; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D013997:Time Factors; D015854:Up-Regulation; D003313:Zea mays / Q000145:classification / Q000235:genetics* / Q000254:growth & development
chemical_list: D026161:MADS Domain Proteins; D010940:Plant Proteins