油茶SAD基因的全长cDNA克隆及生物信息学分析

As a high-grade edible oil tree native in China,tea-oil tree(Camellia oleifera)has the oil-yielded rate of about 55% from its kernel.The recent researches suggested that tea-oil would be one of the best vegetable oils,and even be better than olive oil with its abundant unsaturated fatty acids including 82.6% oleic acid.Stearoyl-ACP desaturase(SAD)is a key enzyme that catalyzes saturated fatty acids(C18∶0)bonded to ACP(Acyl carrier protein)and dehydrogenates the fatty acids into oleic acids,and hence controls the content of oleic acid and the proportion between saturated fatty acids and unsaturated fatty acids.With our previous acquisition of three cDNAs and ESTs of C.oleifera SAD(CoSAD)gene,5'RACE technology was used to obtain the full-length cDNA of CoSAD gene from the nearly matured C.oleifera seed.The comprehensive bioinformatic analyses including sequence characteristics of DNA and amino acid,multi-sequence aligning,identity and homology,molecular clustering,protein physicochemical properties,and protein structural prediction and characteristics were performed.The results may provide the theoretical and material elements for application of CoSAD gene and genetic improvement on other oil plants.