title: Chimeric promoter mediates guard cell-specific gene expression in tobacco under water deficit.
abstract: The engineering of stomatal activity under water deficit through guard cell-specific gene regulation is an effective approach to improve drought tolerance of crops but it requires an appropriate promoter(s) inducible by water deficit in guard cells. We report that a chimeric promoter can induce guard cell-specific gene expression under water deficit. A chimeric promoter, p4xKST82-rd29B, was constructed using a tetramer of the 82 bp guard cell-specific regulatory region of potato KST1 promoter (4xKST82) and Arabidopsis dehydration-responsive rd29B promoter. Transgenic tobacco plants carrying p4xKST82-rd29B:mGFP-GUS exhibited GUS expression in response to water deficit. GUS enzyme activity of p4xKST82-rd29B:mGFP-GUS transgenic plants increased ~300 % by polyethylene glycol treatment compared to that of control plant but not by abscisic acid (ABA), indicating that the p4xKST82-rd29B chimeric promoter can be used to induce the guard cell-specific expression of genes of interest in response to water deficit in an ABA-independent manner.
authors.affiliation: Division of Molecular Breeding, National Academy of Agricultural Science, RDA, Suwon, 441-701, Republic of Korea, jkna.uiuc@gmail.com.
authors.forename: Jong-Kuk
authors.initials: JK
authors.lastname: Na
authors.forename: James D
authors.initials: JD
authors.lastname: Metzger
mesh_terms: D017360:Arabidopsis / Q000235:genetics; D003681:Dehydration; D018506:Gene Expression Regulation, Plant; D017930:Genes, Reporter; D005966:Glucuronidase / Q000032:analysis / Q000235:genetics; D049452:Green Fluorescent Proteins / Q000032:analysis / Q000235:genetics; D059828:Plant Cells / Q000502:physiology*; D030821:Plants, Genetically Modified / Q000235:genetics / Q000502:physiology; D011401:Promoter Regions, Genetic; D011198:Solanum tuberosum / Q000235:genetics; D013312:Stress, Physiological; D014026:Nicotiana / Q000235:genetics / Q000502:physiology*
chemical_list: D049452:Green Fluorescent Proteins; D005966:Glucuronidase