transformation of rapeseed (brassica napus l.) plants with sense and antisense constructs of the fatty acid elongase gene

the biosynthetic pathways of saturated and unsaturated fatty acids consist of many steps controlled by various enzymes. one of the methods for improving oil quality is to change the fatty acid profile through genetic manipulation which requires isolation and characterization of the genes and other cis-acting elements, such as the promoter, involved in fatty acid biosynthesis. b-ketoacyl-coa synthase (kcs) that is the key enzyme in erucic acid biosynthesis. this enzyme is involved in producing eicosanoeic (c20:1) and erucic acids (c22:1) from c18 fatty acids, and is encoded by the fatty acid elongase (fae) gene. specific primers were used to amplify the fae gene and its promoter from genomic dna by using pcr technique. the putative gene and its promoter were cloned in sense and antisense orientation into the plant expression vector (pbi121). the sense and antisense constructs of the fae gene were transformed via agrobacterium-mediated transformation into low erucic acid rapeseed (lear such as pf) and high erucic acid cultivars (hear such as maplus). the transformed plants were screened on kanamycin-containing media and then analysed by pcr and southern blotting techniques. moreover, erucic acid content of the first  generation of transgenic (t0) plants analysed with gas chromatography, showed significant changes in fatty acid composition of transgenic rapeseed plants containing sense and antisense constructs of the fae gene.