title: Effect of different environmental stresses on the expression of oleate desaturase genes and fatty acid composition in olive fruit.
abstract: The regulation of microsomal and plastidial oleate desaturases by low and high temperature, darkness, and wounding was investigated. To this end, their gene expression levels and the fatty acid composition was determined in the mesocarp tissue of olive fruit from the Picual and Arbequina varieties subjected to the corresponding stress treatments. Firstly, a plastidial oleate desaturase from olive was cloned and its functional identity was confirmed by overexpression in Escherichia coli. The results showed that temperature and light regulate olive oleate desaturase genes at transcriptional level. However, no correlation between their expression levels and the linoleic acid content in microsomal and plastidial lipids was found. In addition, the involvement of microsomal but not plastidial oleate desaturases in the wounding response of olive fruit mesocarp is demonstrated. The fatty acid analysis revealed the appearance of palmitolinoleic acid only in microsomal lipids, reaching a maximum 3h after wounding.
authors.affiliation: Instituto de la Grasa (CSIC), Sevilla, Spain.
authors.forename: M Luisa
authors.initials: ML
authors.lastname: Hernández
authors.forename: María N
authors.initials: MN
authors.lastname: Padilla
authors.forename: M Dolores
authors.initials: MD
authors.lastname: Sicardo
authors.forename: Manuel
authors.initials: M
authors.lastname: Mancha
authors.forename: José M
authors.initials: JM
authors.lastname: Martínez-Rivas
mesh_terms: D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D044943:Fatty Acid Desaturases / Q000235:genetics* / Q000378:metabolism*; D005638:Fruit / Q000737:chemistry / Q000201:enzymology / Q000254:growth & development; D015870:Gene Expression; D008055:Lipids / Q000096:biosynthesis*; D031658:Olea / Q000201:enzymology* / Q000235:genetics*; D019301:Oleic Acid / Q000235:genetics / Q000378:metabolism*; D019308:Palmitic Acid / Q000378:metabolism*; D013312:Stress, Physiological / Q000502:physiology*; D013696:Temperature; D013997:Time Factors; D014945:Wound Healing / Q000502:physiology
chemical_list: D008055:Lipids; D019301:Oleic Acid; D019308:Palmitic Acid; D044943:Fatty Acid Desaturases; C040448:delta-12 fatty acid desaturase