CHARACTERIZATION AND VALIDATION OF FAD AND SAD GENES IN OLIVE (OLEA EUROPAEA L.) TISSUE AND DURING FRUIT DEVELOPMENT

CIBELES CONTRERAS; ROBERTO MARIOTTI; NICOLÒ CULTRERA; LUCIANA BALDONI; GUERRERO RUIZ C; ROKA LOUKIA; MOUSAVI SORAYA; PIERLUIGI PIERANTOZZI; DAMIÁN MAESTRI; MARIELA TORRES

Rosario

Simposio; Simposio de Genómica Funcional de Plantas 2017; 2017

IBR Conicet INTA UNR

Stearoyl-ACP desaturase (SADs) and fatty acid desaturases (FADs) play a critical role in plant lipid metabolism, development and acclimation to environmental stresses, and governing fatty acid composition of oil accumulating in seeds and fruits. In our study, three SAD and four FAD candidate genes were identified in olive (Olea europaea) through blasting the genomic scaffolds of the cv. Leccino genome sequences (http:// oleagenome.org/), followed by nucleotide BLAST in the NCBI database. Based on a phylogenetic analysis, the three OeSADs seemed to correspond to SAD1, SAD2 and SAD3 proteins, sharing conserved structure with known plant SAD proteins. FAD genes corresponded respectively to two FAD2.1, one FAD 2.2 and one FAD6. The expression of all genes was tested on different tissues (bud, leaf, cambium, flower, root and fruit) of cv. Leccino, showing that SAD2 and SAD3 genes were mainly expressed in fruit tissues, both FAD2.1 loci were highly expressed in flower, whereas all the others were universally expressed at all tissues. Expression patterns of all genes were also observed in fruits of Leccino and Coratina varieties, both, at 45, 75, 105, 135 and 165 days after flowering (DAF). Finally, considering that FAD and SAD genes show in other species a cold-induced and heat-repressed expression pattern, the potential role of these genes, in temperature stress response, are currently under analysis from three different Argentinian provinces (from the warmest Catamarca to the coldest Neuquén), during fruit development, using Arbequina as reference variety versus Coratina one of the best olive cultivar for fatty acid composition.