title: TEMPRANILLO genes link photoperiod and gibberellin pathways to control flowering in Arabidopsis.
abstract: In Arabidopsis, FLOWERING LOCUS T (FT) promotes flowering in response to long days in the photoperiod pathway, while signalling downstream gibberellin (GA) perception is critical for flowering under short days. Previously we have established that the TEMPRANILLO (TEM) genes have a pivotal role in the direct repression of FT. Here we show that TEM genes directly regulate the expression of the GA(4) biosynthetic genes GA 3-oxidase1 and 2 (GA3OX1 and GA3OX2). Plants overexpressing TEM genes resemble GA-deficient mutants, and conversely, TEM downregulation give rise to elongated hypocotyls perhaps as a result of an increase in GA content. We consistently find that TEM1 represses GA3OX1 and GA3OX2 by directly binding a regulatory region positioned in the first exon. Our results indicate that TEM genes seem to link the photoperiod and GA-dependent flowering pathways, controlling floral transition under inductive and non-inductive day lengths through the regulation of the floral integrators.
authors.affiliation: Centre for Research in Agricultural Genomics, CSIC-IRTA-UAB-UB, Molecular Genetics Department, Parc de Recerca UAB, Bellaterra (Cerdanyola del Vallés), 08193 Barcelona, Spain.
authors.forename: Michela
authors.initials: M
authors.lastname: Osnato
authors.forename: Cristina
authors.initials: C
authors.lastname: Castillejo
authors.forename: Luis
authors.initials: L
authors.lastname: Matías-Hernández
authors.forename: Soraya
authors.initials: S
authors.lastname: Pelaz
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism* / Q000528:radiation effects*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D035264:Flowers / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism / Q000528:radiation effects; D018507:Gene Expression Regulation, Developmental / Q000528:radiation effects; D018506:Gene Expression Regulation, Plant / Q000528:radiation effects; D005875:Gibberellins / Q000378:metabolism*; D017440:Photoperiod; D015398:Signal Transduction; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D005875:Gibberellins; C533191:TEM1 protein, Arabidopsis; D014157:Transcription Factors