title: Hypersensitivity of Arabidopsis TAXIMIN1 overexpression lines to light stress is correlated with decreased sinapoyl malate abundance and countered by the antibiotic cefotaxime.
abstract: Peptide signaling in plants is involved in regulating development, (1,2) ensuring cross pollination through initiation of self-incompatibility (4) and assisting with recognition of beneficial (nitrogen fixing bacteria (5)) or unfavorable organisms (pathogens (6) or herbivores (7)). Peptides function to help plants to respond to a changing environment and improve their chances of survival. Constitutive expression of the gene encoding a novel cysteine rich peptide TAXIMIN1 (TAX1) resulted in fusion of lateral organs and in abnormal fruit morphology. TAX1 signaling functions independently from transcription factors known to play a role in this process such as LATERAL ORGAN FUSION1 (LOF1). Here, we report that the TAX1 promoter is not induced by the LOF1 transcription factor and that the TAX1 peptide neither interferes with transcriptional activation by LOF1.1 or transcriptional repression by LOF1.2. Furthermore, we found that TAX1 overexpressing lines were hypersensitive to continuous light, which may be reflected by a decreased accumulation of the UV-B protecting compound sinapoyl-malate. Finally, adding the antibiotic cefotaxime to the medium surprisingly countered the light hypersensitivity phenotype of TAX1 overexpressing seedlings.
authors.affiliation: a Department of Plant Systems Biology , Flanders Institute for Biotechnology, (VIB) , Technologiepark , Gent , Belgium.|b Department of Plant Biotechnology and Bioinformatics , Ghent University , Technologiepark , Gent , Belgium.|c Institute for Plant Biotechnology , Department of Genetics, Stellenbosch University , Stellenbosch , South Africa.
authors.forename: Janine
authors.initials: J
authors.lastname: Colling
authors.affiliation: a Department of Plant Systems Biology , Flanders Institute for Biotechnology, (VIB) , Technologiepark , Gent , Belgium.|b Department of Plant Biotechnology and Bioinformatics , Ghent University , Technologiepark , Gent , Belgium.
authors.forename: Jacob
authors.initials: J
authors.lastname: Pollier
authors.affiliation: a Department of Plant Systems Biology , Flanders Institute for Biotechnology, (VIB) , Technologiepark , Gent , Belgium.|b Department of Plant Biotechnology and Bioinformatics , Ghent University , Technologiepark , Gent , Belgium.
authors.forename: Robin
authors.initials: R
authors.lastname: Vanden Bossche
authors.affiliation: c Institute for Plant Biotechnology , Department of Genetics, Stellenbosch University , Stellenbosch , South Africa.|d Department of Botany and Zoology , Stellenbosch University , Stellenbosch , South Africa.
authors.forename: Nokwanda Pearl
authors.initials: NP
authors.lastname: Makunga
authors.affiliation: a Department of Plant Systems Biology , Flanders Institute for Biotechnology, (VIB) , Technologiepark , Gent , Belgium.|b Department of Plant Biotechnology and Bioinformatics , Ghent University , Technologiepark , Gent , Belgium.
authors.forename: Laurens
authors.initials: L
authors.lastname: Pauwels
authors.affiliation: a Department of Plant Systems Biology , Flanders Institute for Biotechnology, (VIB) , Technologiepark , Gent , Belgium.|b Department of Plant Biotechnology and Bioinformatics , Ghent University , Technologiepark , Gent , Belgium.
authors.forename: Alain
authors.initials: A
authors.lastname: Goossens
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D017360:Arabidopsis / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D002439:Cefotaxime / Q000494:pharmacology*; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D008027:Light; D008293:Malates / Q000378:metabolism*; D010666:Phenylpropionates / Q000378:metabolism*; D030821:Plants, Genetically Modified; D013312:Stress, Physiological / Q000528:radiation effects*
chemical_list: C079164:2-O-sinapoylmalate; D000900:Anti-Bacterial Agents; D029681:Arabidopsis Proteins; D047908:Intracellular Signaling Peptides and Proteins; D008293:Malates; D010666:Phenylpropionates; C000607732:TAX1 protein, Arabidopsis; D002439:Cefotaxime
keywords: Arabidopsis; boundary formation; cefotaxime; signaling peptide; sinapoyl malate