title: A Flowering Locus C Homolog Is a Vernalization-Regulated Repressor in Brachypodium and Is Cold Regulated in Wheat.
abstract: Winter cereals require prolonged cold to transition from vegetative to reproductive development. This process, referred to as vernalization, has been extensively studied in Arabidopsis (Arabidopsis thaliana). In Arabidopsis, a key flowering repressor called FLOWERING LOCUS C (FLC) quantitatively controls the vernalization requirement. By contrast, in cereals, the vernalization response is mainly regulated by the VERNALIZATION genes, VRN1 and VRN2 Here, we characterize ODDSOC2, a recently identified FLC ortholog in monocots, knowing that it belongs to the FLC lineage. By studying its expression in a diverse set of Brachypodium accessions, we find that it is a good predictor of the vernalization requirement. Analyses of transgenics demonstrated that BdODDSOC2 functions as a vernalization-regulated flowering repressor. In most Brachypodium accessions BdODDSOC2 is down-regulated by cold, and in one of the winter accessions in which this down-regulation was evident, BdODDSOC2 responded to cold before BdVRN1. When stably down-regulated, the mechanism is associated with spreading H3K27me3 modifications at the BdODDSOC2 chromatin. Finally, homoeolog-specific gene expression analyses identify TaAGL33 and its splice variant TaAGL22 as the FLC orthologs in wheat (Triticum aestivum) behaving most similar to Brachypodium ODDSOC2 Overall, our study suggests that ODDSOC2 is not only phylogenetically related to FLC in eudicots but also functions as a flowering repressor in the vernalization pathway of Brachypodium and likely other temperate grasses. These insights could prove useful in breeding efforts to refine the vernalization requirement of temperate cereals and adapt varieties to changing climates.
authors.affiliation: Department of Biology, KU Leuven, B-3001 Leuven, Belgium (N.S., P.R., N.D., S.T., K.G.).|Bayer Crop Science, B-9052 Gent, Belgium (M.D., T.M., A.R.); and.|Institute for Biochemistry and Biology, Potsdam University, 14476 Potsdam-Golm, Germany (K.K.).
authors.forename: Neha
authors.initials: N
authors.lastname: Sharma
authors.affiliation: Department of Biology, KU Leuven, B-3001 Leuven, Belgium (N.S., P.R., N.D., S.T., K.G.).|Bayer Crop Science, B-9052 Gent, Belgium (M.D., T.M., A.R.); and.|Institute for Biochemistry and Biology, Potsdam University, 14476 Potsdam-Golm, Germany (K.K.).
authors.forename: Philip
authors.initials: P
authors.lastname: Ruelens
authors.affiliation: Department of Biology, KU Leuven, B-3001 Leuven, Belgium (N.S., P.R., N.D., S.T., K.G.).|Bayer Crop Science, B-9052 Gent, Belgium (M.D., T.M., A.R.); and.|Institute for Biochemistry and Biology, Potsdam University, 14476 Potsdam-Golm, Germany (K.K.).
authors.forename: Mariëlla
authors.initials: M
authors.lastname: D'hauw
authors.affiliation: Department of Biology, KU Leuven, B-3001 Leuven, Belgium (N.S., P.R., N.D., S.T., K.G.).|Bayer Crop Science, B-9052 Gent, Belgium (M.D., T.M., A.R.); and.|Institute for Biochemistry and Biology, Potsdam University, 14476 Potsdam-Golm, Germany (K.K.).
authors.forename: Thomas
authors.initials: T
authors.lastname: Maggen
authors.affiliation: Department of Biology, KU Leuven, B-3001 Leuven, Belgium (N.S., P.R., N.D., S.T., K.G.).|Bayer Crop Science, B-9052 Gent, Belgium (M.D., T.M., A.R.); and.|Institute for Biochemistry and Biology, Potsdam University, 14476 Potsdam-Golm, Germany (K.K.).
authors.forename: Niklas
authors.initials: N
authors.lastname: Dochy
authors.affiliation: Department of Biology, KU Leuven, B-3001 Leuven, Belgium (N.S., P.R., N.D., S.T., K.G.).|Bayer Crop Science, B-9052 Gent, Belgium (M.D., T.M., A.R.); and.|Institute for Biochemistry and Biology, Potsdam University, 14476 Potsdam-Golm, Germany (K.K.).
authors.forename: Sanne
authors.identifier: 0000-0003-0637-4057
authors.initials: S
authors.lastname: Torfs
authors.affiliation: Department of Biology, KU Leuven, B-3001 Leuven, Belgium (N.S., P.R., N.D., S.T., K.G.).|Bayer Crop Science, B-9052 Gent, Belgium (M.D., T.M., A.R.); and.|Institute for Biochemistry and Biology, Potsdam University, 14476 Potsdam-Golm, Germany (K.K.).
authors.forename: Kerstin
authors.initials: K
authors.lastname: Kaufmann
authors.affiliation: Department of Biology, KU Leuven, B-3001 Leuven, Belgium (N.S., P.R., N.D., S.T., K.G.).|Bayer Crop Science, B-9052 Gent, Belgium (M.D., T.M., A.R.); and.|Institute for Biochemistry and Biology, Potsdam University, 14476 Potsdam-Golm, Germany (K.K.).
authors.forename: Antje
authors.initials: A
authors.lastname: Rohde
authors.affiliation: Department of Biology, KU Leuven, B-3001 Leuven, Belgium (N.S., P.R., N.D., S.T., K.G.); koen.geuten@kuleuven.be.|Bayer Crop Science, B-9052 Gent, Belgium (M.D., T.M., A.R.); and koen.geuten@kuleuven.be.|Institute for Biochemistry and Biology, Potsdam University, 14476 Potsdam-Golm, Germany (K.K.) koen.geuten@kuleuven.be.
authors.forename: Koen
authors.identifier: 0000-0002-9692-4499
authors.initials: K
authors.lastname: Geuten
mesh_terms: D029681:Arabidopsis Proteins / Q000235:genetics; D058431:Brachypodium / Q000235:genetics / Q000502:physiology*; D002843:Chromatin / Q000235:genetics / Q000378:metabolism; D003080:Cold Temperature; D035264:Flowers / Q000235:genetics; D018506:Gene Expression Regulation, Plant; D055785:Gene Knockdown Techniques; D026161:MADS Domain Proteins / Q000235:genetics; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D014908:Triticum / Q000235:genetics / Q000502:physiology*
chemical_list: D029681:Arabidopsis Proteins; D002843:Chromatin; C418902:At5g10140 protein, Arabidopsis; D026161:MADS Domain Proteins; D010940:Plant Proteins; D012097:Repressor Proteins