title: PORPHOBILINOGEN DEAMINASE deficiency alters vegetative and reproductive development and causes lesions in Arabidopsis.
abstract: The Arabidopsis rugosa1 (rug1) mutant has irregularly shaped leaves and reduced growth. In the absence of pathogens, leaves of rug1 plants have spontaneous lesions reminiscent of those seen in lesion-mimic mutants; rug1 plants also express cytological and molecular markers associated with defence against pathogens. These rug1 phenotypes are made stronger by dark/light transitions. The rug1 mutant also has delayed flowering time, upregulation of the floral repressor FLOWERING LOCUS C (FLC) and downregulation of the flowering promoters FT and SOC1/AGL20. Vernalization suppresses the late flowering phenotype of rug1 by repressing FLC. Microarray analysis revealed that 280 nuclear genes are differentially expressed between rug1 and wild type; almost a quarter of these genes are involved in plant defence. In rug1, the auxin response is also affected and several auxin-responsive genes are downregulated. We identified the RUG1 gene by map-based cloning and found that it encodes porphobilinogen deaminase (PBGD), also known as hydroxymethylbilane synthase, an enzyme of the tetrapyrrole biosynthesis pathway, which produces chlorophyll, heme, siroheme and phytochromobilin in plants. PBGD activity is reduced in rug1 plants, which accumulate porphobilinogen. Our results indicate that Arabidopsis PBGD deficiency impairs the porphyrin pathway and triggers constitutive activation of plant defence mechanisms leading to leaf lesions and affecting vegetative and reproductive development.
authors: Instituto de Bioingeniería, Universidad Miguel Hernández, Campus de Elche, Elche, Spain.
authors: Víctor
authors: V
authors: Quesada
authors: Raquel
authors: R
authors: Sarmiento-Mañús
authors: Rebeca
authors: R
authors: González-Bayón
authors: Andrea
authors: A
authors: Hricová
authors: María Rosa
authors: MR
authors: Ponce
authors: José Luis
authors: JL
authors: Micol
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D001664:Biliverdine / Q000031:analogs & derivatives / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D006418:Heme / Q000378:metabolism; D011163:Hydroxymethylbilane Synthase / Q000235:genetics* / Q000378:metabolism; D007210:Indoleacetic Acids / Q000494:pharmacology; D026161:MADS Domain Proteins / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D010641:Phenotype; D063245:Plant Development / Q000187:drug effects / Q000235:genetics*; D010937:Plant Growth Regulators / Q000494:pharmacology; D018515:Plant Leaves / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000187:drug effects / Q000378:metabolism; D011162:Porphobilinogen / Q000378:metabolism; D012098:Reproduction / Q000187:drug effects / Q000235:genetics*
chemical_list: C419046:AGL20 protein, Arabidopsis; D029681:Arabidopsis Proteins; C418902:At5g10140 protein, Arabidopsis; D007210:Indoleacetic Acids; D026161:MADS Domain Proteins; D010937:Plant Growth Regulators; D002734:Chlorophyll; C075811:phytochromobilin; D006418:Heme; D011162:Porphobilinogen; D011163:Hydroxymethylbilane Synthase; D001664:Biliverdine