AUTHOR=Hernández M. Luisa , Sicardo M. Dolores , Alfonso Miguel , Martínez-Rivas José M. 

TITLE=Transcriptional Regulation of Stearoyl-Acyl Carrier Protein Desaturase Genes in Response to Abiotic Stresses Leads to Changes in the Unsaturated Fatty Acids Composition of Olive Mesocarp

JOURNAL=Frontiers in Plant Science

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2019.00251

DOI=10.3389/fpls.2019.00251

ISSN=1664-462X

ABSTRACT=<p>In higher plants, the stearoyl-acyl carrier protein desaturase (SAD) catalyzes the first desaturation step leading to oleic acid, which can be further desaturated to linoleic and α-linolenic acids. Therefore, SAD plays an essential role in determining the overall content of unsaturated fatty acids (UFA). We have investigated how <italic>SAD</italic> genes expression and UFA composition are regulated in olive (<italic>Olea europaea</italic>) mesocarp tissue from Picual and Arbequina cultivars in response to different abiotic stresses. The results showed that olive <italic>SAD</italic> genes are transcriptionally regulated by temperature, darkness and wounding. The increase in <italic>SAD</italic> genes expression levels observed in Picual mesocarp exposed to low temperature brought about a modification in the UFA content of microsomal membrane lipids. In addition, darkness caused the down-regulation of <italic>SAD</italic> genes transcripts, together with a decrease in the UFA content of chloroplast lipids. The differential role of olive <italic>SAD</italic> genes in the wounding response was also demonstrated. These data point out that different environmental stresses can modify the UFA composition of olive mesocarp through the transcriptional regulation of <italic>SAD</italic> genes, affecting olive oil quality.</p>