title: GASA4, one of the 14-member Arabidopsis GASA family of small polypeptides, regulates flowering and seed development.
abstract: Members of the plant-specific gibberellic acid-stimulated Arabidopsis (GASA) gene family play roles in hormone response, defense and development. We have identified six new Arabidopsis GASA genes, bringing the total number of family members to 14. Here we show that these genes all encode small polypeptides that share the common structural features of an N-terminal putative signal sequence, a highly divergent intermediate region and a conserved 60 amino acid C-terminal domain containing 12 conserved cysteine residues. Analysis of promoter::GUS (beta-glucuronidase) transgenic plants representing six different GASA loci reveals that the promoters are activated in a variety of stage- and tissue-specific patterns during development, indicating that the GASA genes are involved in diverse processes. Characterization of GASA4 shows that the promoter is active in the shoot apex region, developing flowers and developing embryos. Phenotypic analyses of GASA4 loss-of-function and gain-of-function lines indicate that GASA4 regulates floral meristem identity and also positively affects both seed size and total seed yield.
authors.affiliation: Genetwister Technologies BV, PO Box 193, NL-6700 AD Wageningen, The Netherlands.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Roxrud
authors.forename: Stein Erik
authors.initials: SE
authors.lastname: Lid
authors.forename: Jennifer C
authors.initials: JC
authors.lastname: Fletcher
authors.forename: Ed D L
authors.initials: ED
authors.lastname: Schmidt
authors.forename: Hilde-Gunn
authors.initials: HG
authors.lastname: Opsahl-Sorteberg
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D017124:Conserved Sequence; D035264:Flowers / Q000254:growth & development; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D005966:Glucuronidase / Q000235:genetics / Q000378:metabolism; D006651:Histocytochemistry; D008969:Molecular Sequence Data; D005810:Multigene Family; D010641:Phenotype; D030821:Plants, Genetically Modified; D011401:Promoter Regions, Genetic; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012639:Seeds / Q000254:growth & development; D017386:Sequence Homology, Amino Acid
chemical_list: D029681:Arabidopsis Proteins; D011993:Recombinant Fusion Proteins; C093242:GASA protein, Arabidopsis; D005966:Glucuronidase