Saeki Kazuhiro, Matsumoto Kazuya, Kinoshita Mikio, Suzuki Iwane, Tasaka Yasushi, Kano Koichiro, Taguchi Yoshitomo, Mikami Koji, Hirabayashi Masumi, Kashiwazaki Naomi, Hosoi Yoshihiko, Murata Norio, Iritani Akira
Institute of Advanced Technology, Kinki University, Kainan, Wakayama 642-0017, Japan.
Proc Natl Acad Sci U S A. 2004 Apr 27;101(17):6361-6. doi: 10.1073/pnas.0308111101. Epub 2004 Apr 5.
Linoleic acid (18:2n-6) and alpha-linolenic acid (18:3n-3) are polyunsaturated fatty acids that are essential for mammalian nutrition, because mammals lack the desaturases required for synthesis of Delta12 (n-6) and n-3 fatty acids. Many plants can synthesize these fatty acids and, therefore, to examine the effects of a plant desaturase in mammals, we generated transgenic pigs that carried the fatty acid desaturation 2 gene for a Delta12 fatty acid desaturase from spinach. Levels of linoleic acid (18:2n-6) in adipocytes that had differentiated in vitro from cells derived from the transgenic pigs were approximately 10 times higher than those from wild-type pigs. In addition, the white adipose tissue of transgenic pigs contained approximately 20% more linoleic acid (18:2n-6) than that of wild-type pigs. These results demonstrate the functional expression of a plant gene for a fatty acid desaturase in mammals, opening up the possibility of modifying the fatty acid composition of products from domestic animals by transgenic technology, using plant genes for fatty acid desaturases.
亚油酸（18:2n - 6）和α-亚麻酸（18:3n - 3）是多不饱和脂肪酸，对哺乳动物营养至关重要，因为哺乳动物缺乏合成Δ12（n - 6）和n - 3脂肪酸所需的去饱和酶。许多植物能够合成这些脂肪酸，因此，为了研究植物去饱和酶在哺乳动物中的作用，我们培育了携带菠菜Δ12脂肪酸去饱和酶脂肪酸去饱和2基因的转基因猪。从转基因猪来源的细胞体外分化得到的脂肪细胞中亚油酸（18:2n - 6）水平比野生型猪来源的脂肪细胞高约10倍。此外，转基因猪的白色脂肪组织中亚油酸（18:2n - 6）含量比野生型猪多约20%。这些结果证明了植物脂肪酸去饱和酶基因在哺乳动物中的功能性表达，为利用植物脂肪酸去饱和酶基因通过转基因技术改变家畜产品的脂肪酸组成开辟了可能性。
