title: The SlFRK4 promoter is active only during late stages of pollen and anther development.
abstract: Carbohydrates are essential for male gametophyte development. However, our understanding of the mechanism by which the sugar supply is controlled in the stamen is still in its infancy. We previously reported on the stamen-specific expression of the tomato (Solanum lycopersicum) sugar metabolic gene, fructokinase 4 (SlFRK4). Here, we present the cloning and the characterization of the SlFRK4 promoter and show its differential activation during anther development. We also show that the tissue-specific expression of SlFRK4 promoter is maintained in Arabidopsis thaliana. By histochemical analyses of the GUS reporter gene and DTA toxin driven by the SlFRK4 promoter, we show that the SlFRK4 promoter is gradually activated in pollen grains throughout the later stages of anther development and upon pollen germination. In addition, we analyzed the expression profile of SlFRK4 and other sugar metabolic genes and found that SlFRK4 and the invertase LIN7 are co-expressed in mature and germinated pollen. These findings point to the existence of a specialized mechanism in which carbohydrates are provided to the male gametophyte during the later stages of its development and suggest a valuable tool for manipulating the development of male gametophytes in crop species.
authors.affiliation: Institute of Plant Science, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel.
authors.forename: Rakefet
authors.initials: R
authors.lastname: David-Schwartz
authors.forename: Liron
authors.initials: L
authors.lastname: Weintraub
authors.forename: Roee
authors.initials: R
authors.lastname: Vidavski
authors.forename: Hanita
authors.initials: H
authors.lastname: Zemach
authors.forename: Leonid
authors.initials: L
authors.lastname: Murakhovsky
authors.forename: Dvora
authors.initials: D
authors.lastname: Swartzberg
authors.forename: David
authors.initials: D
authors.lastname: Granot
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism; D050260:Carbohydrate Metabolism / Q000235:genetics; D002241:Carbohydrates; D004167:Diphtheria Toxin / Q000235:genetics; D035264:Flowers / Q000033:anatomy & histology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D005631:Fructokinases / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000235:genetics*; D017930:Genes, Reporter; D018551:Solanum lycopersicum / Q000033:anatomy & histology / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D009928:Organ Specificity; D010446:Peptide Fragments / Q000235:genetics; D010641:Phenotype; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified; D011058:Pollen / Q000033:anatomy & histology / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000235:genetics*; D018749:RNA, Plant / Q000235:genetics; D059467:Transcriptome; D043324:beta-Fructofuranosidase / Q000235:genetics / Q000378:metabolism
chemical_list: D002241:Carbohydrates; D004167:Diphtheria Toxin; D010446:Peptide Fragments; D010940:Plant Proteins; D018749:RNA, Plant; C029795:diphtheria toxin fragment A; D005631:Fructokinases; C046173:fructokinase; D043324:beta-Fructofuranosidase