title: Isolation and functional characterization of two novel seed-specific promoters from sunflower (Helianthus annuus L.).
abstract: The promoter region of two sunflower (Helianthus annuus L. HA89 genotype) seed specifically expressed genes, coding for an oleate desaturase (HaFAD2-1) and a lipid transfer protein (HaAP10), were cloned and in silico characterized. The isolated fragments are 867 and 964 bp long, respectively, and contain several seed-specific motifs, such as AACA motif, ACGT element, E-Boxes, SEF binding sites and GCN4 motif. Functional analysis of these promoters in transgenic Arabidopsis plants was investigated after fusing them with the beta-glucuronidase (GUS) reporter gene. None of the promoters triggered GUS activity in any vegetative tissue, with the exception of early seedling cotyledons. HaFAD2-1 and HaAP10 promoters were tested along seed development from globular stage to mature seeds. GUS staining was restricted to embryonic tissue and quantitative fluorometric assays showed high activity values at the later stages of development. In this work we demonstrate that HaFAD2-1 promoter is as strong as 35S promoter even though it is a tissue-specific promoter and its activity derived just from the embryo, thus confirming that it can be considered a strong highly specific seed promoter useful for biotechnology applications.
authors.affiliation: Instituto de Biotecnología, CNIA, Instituto Nacional de Tecnología Agropecuaria-Castelar, Los Reseros y Nicolas Repeto, 1686 Hurlingham, Buenos Aires Province, Argentina. dzavallo@cnia.inta.gov.ar
authors.forename: Diego
authors.initials: D
authors.lastname: Zavallo
authors.forename: Marisa
authors.initials: M
authors.lastname: Lopez Bilbao
authors.forename: H Esteban
authors.initials: HE
authors.lastname: Hopp
authors.forename: Ruth
authors.initials: R
authors.lastname: Heinz
mesh_terms: D017360:Arabidopsis / Q000235:genetics; D002352:Carrier Proteins / Q000235:genetics; D003001:Cloning, Molecular; D044943:Fatty Acid Desaturases / Q000235:genetics; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D006368:Helianthus / Q000235:genetics*; D044925:Oxidoreductases Acting on CH-CH Group Donors / Q000235:genetics; D010940:Plant Proteins / Q000235:genetics; D030821:Plants, Genetically Modified / Q000235:genetics; D011401:Promoter Regions, Genetic; D018749:RNA, Plant / Q000235:genetics; D012639:Seeds / Q000235:genetics*
chemical_list: D002352:Carrier Proteins; D010940:Plant Proteins; D018749:RNA, Plant; C030363:lipid transfer protein; D044943:Fatty Acid Desaturases; C021904:Phosphatidylcholine desaturase; D044925:Oxidoreductases Acting on CH-CH Group Donors