title: Suppression of allene oxide synthase 3 in potato increases degree of arbuscular mycorrhizal fungal colonization.
abstract: Arbuscular mycorrhizal (AM) is a mutually beneficial interaction among higher plants and soil fungi of the phylum Glomeromycota. Numerous studies have pointed that jasmonic acid plays an important role in the development of the intraradical fungus. This compound belongs to a group of biologically active compounds known as oxylipins which are derived from the oxidative metabolism of polyunsaturated fatty acids. Studies of the regulatory role played by oxylipins in AM colonization have generally focused on jasmonates, while few studies exist on the 9-LOX pathway of oxylipins during AM formation. Here, the cDNA of Allene oxide synthase 3 (AOS3), a key enzyme in the 9-LOX pathway, was used in the RNA interference (RNAi) system to transform potato plants in order to suppress its expression. Results show increases in AOS3 gene expression and 9-LOX products in roots of wild type potato mycorrhizal plants. The suppression of AOS3 gene expression increases the percentage of root with mycorrhizal colonization at early stages of AM formation. AOS3 RNA interference lead to an induction of LOXA and 13-LOX genes, a reduction in AOS3 derived 9-LOX oxylipin compounds and an increase in jasmonic acid content, suggesting compensation between 9 and 13-LOX pathways. The results in a whole support the hypothesis of a regulatory role for the 9-LOX oxylipin pathway during mycorrhization.
authors.affiliation: Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín (EEZ), CSIC, Calle Profesor Albareda n°1, 18008 Granada, Spain.
authors.forename: Rafael Jorge León
authors.initials: RJ
authors.lastname: Morcillo
authors.affiliation: Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín (EEZ), CSIC, Calle Profesor Albareda n°1, 18008 Granada, Spain.
authors.forename: María Isabel Tamayo
authors.initials: MI
authors.lastname: Navarrete
authors.affiliation: Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín (EEZ), CSIC, Calle Profesor Albareda n°1, 18008 Granada, Spain.
authors.forename: Juan Antonio Ocampo
authors.initials: JA
authors.lastname: Bote
authors.affiliation: Department of Plant Molecular Genetics, Centro Nacional de Biotecnología (CNB), CSIC, Calle Darwin n° 3, 28049 Madrid, Spain.
authors.forename: Salomé Prat
authors.initials: SP
authors.lastname: Monguio
authors.affiliation: Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín (EEZ), CSIC, Calle Profesor Albareda n°1, 18008 Granada, Spain. Electronic address: josemanuel.garcia@eez.csic.es.
authors.forename: José Manuel
authors.initials: JM
authors.lastname: García-Garrido
mesh_terms: D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism; D018744:DNA, Plant / Q000235:genetics / Q000378:metabolism; D019746:Intramolecular Oxidoreductases / Q000235:genetics* / Q000378:metabolism; D058945:Lipoxygenases / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D038821:Mycorrhizae / Q000502:physiology*; D054883:Oxylipins / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D034622:RNA Interference; D012231:Rhizobium / Q000502:physiology*; D011198:Solanum tuberosum / Q000235:genetics* / Q000378:metabolism / Q000382:microbiology*
chemical_list: D018076:DNA, Complementary; D018744:DNA, Plant; D054883:Oxylipins; D010940:Plant Proteins; D058945:Lipoxygenases; D019746:Intramolecular Oxidoreductases; C021377:hydroperoxide isomerase
keywords: 9-LOX pathway; Allene oxide synthase; Arbuscular mycorrhizal; Oxylipins