title: Molecular cloning, functional characterization and transcriptional regulation of a 9-lipoxygenase gene from olive.
abstract: A lipoxygenase (LOX) cDNA clone (Oep2LOX1) has been isolated from olive fruit (Olea europaea cv. Picual). The deduced amino acid sequence displayed significant similarity to known plant LOX1 sequences. Genomic Southern blot analysis suggests that only one copy of Oep2LOX1 is present in the olive genome. Linolenic acid was the preferred substrate for the recombinant Oep2LOX1, which produced almost exclusively 9-hydroperoxide when linolenic acid was used as substrate, whereas a mixture of 9- and 13-hydroperoxides in a ratio 4:1 was formed from linoleic acid. Expression levels were measured in different tissues of Picual and Arbequina cultivars, including the mesocarp and seed during development and ripening of olive fruit. The results showed that Oep2LOX1 transcript level is spatially and temporally regulated. Besides, the transcriptional regulation of the Oep2LOX1 gene in response to different abiotic stresses was also investigated. Temperature, light and wounding regulate Oep2LOX1 gene expression in olive fruit mesocarp. The physiological role of the Oep2LOX1 gene during olive fruit ripening and in the stress response is discussed.
authors.affiliation: Instituto de la Grasa, Avda. Padre García Tejero 4, 41012 Seville, Spain.
authors.forename: María N
authors.initials: MN
authors.lastname: Padilla
authors.forename: M Luisa
authors.initials: ML
authors.lastname: Hernández
authors.forename: Carlos
authors.initials: C
authors.lastname: Sanz
authors.forename: José M
authors.initials: JM
authors.lastname: Martínez-Rivas
mesh_terms: D000595:Amino Acid Sequence; D015139:Blotting, Southern; D003001:Cloning, Molecular; D018076:DNA, Complementary; D005228:Fatty Acids, Essential / Q000378:metabolism*; D005638:Fruit / Q000201:enzymology*; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D016678:Genome; D008027:Light; D019787:Linoleic Acid / Q000378:metabolism; D008084:Lipoxygenase / Q000235:genetics* / Q000378:metabolism; D031658:Olea / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism; D010935:Plant Diseases / Q000235:genetics; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins; D013312:Stress, Physiological / Q000235:genetics*; D013696:Temperature; D017962:alpha-Linolenic Acid / Q000378:metabolism
chemical_list: D018076:DNA, Complementary; D005228:Fatty Acids, Essential; D010940:Plant Proteins; D011994:Recombinant Proteins; D017962:alpha-Linolenic Acid; D019787:Linoleic Acid; D008084:Lipoxygenase