Characterization and validation of olive FAD and SAD gene families: expression analysis in different tissues and during fruit development

CONTRERAS CIBELES; MARIOTTI,ROBERTO; MOUSAVI, SORAYA; BALDONI, LUCIANA; GUERRERO,C.; ROKA, L.; CULTRERA, NICCOLO; PIERANTOZZI, PIERLUIGI; MAESTRI, DAMIAN; GENTILI LUCIANA; TIVANI, MARTIN; TORRES,MARIELA

MOLECULAR BIOLOGY REPORTS

SPRINGER

Lugar: Berlin; Año: 2020

0301-4851

Stearoyl-ACP desaturases (SADs) and fatty acid desaturases (FADs) play a critical role in plant lipid metabolism and alsoafect oil fatty acid composition introducing double bonds into the hydrocarbon chains to produce unsaturated fatty acids.In the present study, the genomic sequences of three SAD and three FAD candidate genes were characterized in olive andtheir expression was evaluated in diferent plant tissues. OeSAD genes corresponded to olive SAD1 and SAD2 and to a newlyidentifed OeSAD4, sharing the conserved protein structure with other plant species. On the other hand, the full-lengthgenomic sequences of two microsomal OeFAD genes (FAD2-1 and FAD2-2) and the plastidial FAD6, were released. Whenthe level of expression was tested on diferent tissues of cv. Leccino, OeSAD1 and OeSAD2 were mainly expressed in thefruits, while OeFAD genes showed the lowest expression in this tissue. The mRNA profling of all genes was directly studiedin fruits of Leccino and Coratina cultivars during fruit development. In both genotypes, the expression level of OeSAD1and OeSAD2 had the highest value during and after the pit-hardening period, when oil accumulation in fruit mesocarp isintensively increasing. Furthermore, the expression level of both OeFAD2 genes, which were the main candidates for oleicacid desaturation, were almost negligible during fruit ripening. These results have made possible to defne candidate genesof the machinery regulation of fatty acid composition in olive oil, providing information on their sequence, gene structureand chromosomal location.