Transit Peptide-mediated Location Of Yeast Acyl-?9 Desaturase In Plastid Leads To Biosynthesis And Accumulation Of Palmitoleic Acid In Tobacco Leaf Tissue

Transit peptide was a polypeptide with several dozens amino acid sequences which existed in the chloroplast protein N-end. It could not only guide the chloroplast protein to locate in the chloroplast, but also guide heterologous protein to chloroplast. CoA-?9D was a desaturation enzyme which could express on the endoplasmic reticulum. In practical applications, more palmitoleic acids (16:1) was expected to obtain to meet the needs of the market for biodiesel. Palmitoleic acids obtained from ACP-?9D was catalyzed by the palm acid only, so in our study CoA-Sc?9D was guided to express in the plastid by transit peptide for increasing the palmitoleic acid.Tobacco leaves was a material with a big biomass in this study. The CoA-Sc?9D was overexpressed to enhance the content of monounsaturated fatty acids in leaves, and the high quality tobacco leaf for fuel oil was cultivated. The commercial production of renewable energy as "the green energy" was realized and economic efficiency of tobacco was increased without competing with human's foods tuff. There were three main results in the study:(1)The transit peptides were cloned from Doxantha unguis and Arabidopsis, and connected with plant expression vector pBI121-Sc?9D.(2) The tobacco KY160 genetic transformation system mediated by Agrobacterium was optimized.(3)Expression of Sc?9D guided by MucTP and AtTP might increase the palmitoleic acids to 15.7% and 21.7% respectively, compared with 8.3% expression of Sc?9D without transit peptide. Correspondingly, palm acid reduced to 11.9% and 11.1% from 12.6%.(4)Compared with AtTP, MucTP had a higher efficiency on guiding target genes.