title: Arabidopsis thaliana plant defensin AtPDF1.1 is involved in the plant response to biotic stress.
abstract: *Previously, it was shown that the Arabidopsis thaliana plant defensins AtPDF1.1 (At1g75830) and AtPDF1.2a (At5g44420) exert in vitro antimicrobial properties and that their corresponding genes are expressed in seeds and induced in leaves upon pathogen attack, respectively. *In this study, the expression profile of both AtPDF1.1 and AtPDF1.2a is analysed in wild-type plants upon different stress-related treatments and the effect of modulation of their expression in transgenic plants is examined in both host and nonhost resistance. *AtPDF1.1, which was originally considered to be seed-specific, is demonstrated to be locally induced in leaves upon fungal attack and exhibits an expression profile distinct from that of AtPDF1.2a, a gene frequently used as marker for the ethylene/jasmonate-mediated signaling pathway. Transgenic plants with modulated AtPDF1.1 or AtPDF1.2a gene expression show no altered phenotype upon Botrytis cinerea inoculation. However, constitutive overexpression of AtPDF1.1 in A. thaliana leads to a reduction in symptoms caused by the nonhost Cercospora beticola causing non-spreading spots on A. thaliana leaves. *These results indicate that AtPDF1.1 and AtPDF1.2a clearly differ regarding their expression profile and functionality in planta. It emphasizes the additional level of complexity and fine-tuning within the highly redundant plant defensin genes in A. thaliana.
authors.forename: Barbara M A
authors.initials: BMA
authors.lastname: De Coninck
authors.forename: Jan
authors.initials: J
authors.lastname: Sels
authors.forename: Esther
authors.initials: E
authors.lastname: Venmans
authors.affiliation: Center of Microbial and Plant Genetics, Katholieke Universiteit Leuven, Kasteelpark Arenberg 20, B-3001 Heverlee, Belgium.
authors.forename: Wannes
authors.initials: W
authors.lastname: Thys
authors.affiliation: Center of Microbial and Plant Genetics, Katholieke Universiteit Leuven, Kasteelpark Arenberg 20, B-3001 Heverlee, Belgium.
authors.forename: Inge J W M
authors.initials: IJWM
authors.lastname: Goderis
authors.affiliation: Center of Microbial and Plant Genetics, Katholieke Universiteit Leuven, Kasteelpark Arenberg 20, B-3001 Heverlee, Belgium.
authors.forename: Delphine
authors.initials: D
authors.lastname: Carron
authors.affiliation: Center of Microbial and Plant Genetics, Katholieke Universiteit Leuven, Kasteelpark Arenberg 20, B-3001 Heverlee, Belgium.
authors.forename: Stijn L
authors.initials: SL
authors.lastname: Delauré
authors.affiliation: Center of Microbial and Plant Genetics, Katholieke Universiteit Leuven, Kasteelpark Arenberg 20, B-3001 Heverlee, Belgium.
authors.forename: Bruno P A
authors.initials: BPA
authors.lastname: Cammue
authors.forename: Miguel F C
authors.initials: MFC
authors.lastname: De Bolle
authors.forename: Janick
authors.initials: J
authors.lastname: Mathys
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism* / Q000382:microbiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D023082:Defensins / Q000235:genetics / Q000378:metabolism*; D005658:Fungi; D020869:Gene Expression Profiling; D017343:Genes, Plant; D054884:Host-Pathogen Interactions; D010641:Phenotype; D010935:Plant Diseases / Q000235:genetics / Q000382:microbiology*; D057865:Plant Immunity / Q000235:genetics; D018515:Plant Leaves / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000378:metabolism; D015398:Signal Transduction; D013312:Stress, Physiological
chemical_list: D029681:Arabidopsis Proteins; D023082:Defensins; C556912:PDF1.1 protein, Arabidopsis; C487542:At5g44420 protein, Arabidopsis