Delta 15 desaturase 유전자 억제에 의해 알파리놀렌산 함량이 낮은 들깨 육성

Development of Perilla frutescens with Low Levels of Alpha-Linolenic Acid by Inhibition of a delta 15 desaturase Gene

Perilla is an oilseed crop cultivated in Korea since ancient times. Due to the high α-linolenic acid content in perilla, perilla seed oil can easily become rancid. α-Linolenic acid is synthesized by two enzymes, endoplasmic reticulum-localized Δ15 desaturase (FAD3) and chloroplast-localized Δ15 desaturase (FAD7) in vivo. In order to lower the α-linolenic acid content of the seed oil without disturbing plant growth, we tried to suppress the expression of only the FAD3 gene using RNA interference, whilst maintaining the expression of the FAD7 gene. Seventeen transgenic plants with herbicide (Basta TM ) resistance were obtained by Agrobacterium-mediated transformation using hypocotyls of perilla plants. The transgenic plants were firstly confirmed by treatment with 0.3% (v/v) Basta TM herbicide, and the expression of FAD3 was measured by Northern blot analysis. The α-linolenic acid content was 10-20%, 30-40%, and 60% in two, seven, and three of the twelve T1 transgenic perilla plants which had enough seeds to be analyzed for fatty acid composition, respectively. Analysis of the fatty acid composition of T2 progeny seeds from T1 plants with the lowest α-linolenic acid content showed that the homozygous lines had 6-10% α-linolenic acid content and the heterozygous lines had 20-26% α-linolenic acid content. It is expected that the reduction in α-linolenic acid content in perilla seed oil will prevent rancidity and can be utilized for the production of high-value functional ingredients such as high γ-linolenic acid.