Studies about the improvement of soybean storage lipids by using the combination of induced mutation and gene transfer techniques.

在本研究中，我们试图开发一种既具有改性脂肪酸组成又具有高产油率的大豆新品种，并通过组合获得了以下结果1。在几个高油酸突变体中鉴定出相应的基因，其中两个（KK21和M23）明确突变发生在编码微体ω-6脂肪酸去饱和酶的gmfad2 - 1位点。此外，低亚麻酸突变体的J18和M5在GmFAD3-1a位点发生突变，M24的对应基因也明确突变发生在另一个GmFAD3-1b位点，该位点编码微粒体ω-3脂肪酸去饱和酶基因。结果表明，在培养基中添加20mM焦谷氨酸可显著提高大豆未成熟胚的胚发生效率，添加0.2%多蛋白胨S对胚的生长也有促进作用。在此基础上，引入EGFP基因，培育出日本九州126转基因大豆品系3个。3 .我们成功培育了GmFAD3-1a基因转基因水稻，使种子中α-亚麻酸含量比非转基因水稻提高了10倍以上，开发了一种新的植物转化RNAi载体，并证实了这些技术对利用转基因技术改良大豆脂质是有效的。成功克隆了二酰基甘油酰基转移酶（DGAT）的基因（cDNA和基因组DNA），该基因可控制油脂组成（TAG/DAG比）和产油率。

In this study, we have attempted to develop a novel soybean germplasm which equips with both modified fatty acid composition and high oil productivity, and have obtained following results by using the combination1. The corresponding genes were identified in several high oleic acid mutants, and two of them (KK21 and M23) were clarified that mutations occurred at GmFAD2-I locus which encodes a microsomal ω-6 fatty acid desaturase. In addition, J18 and M5 of low linolenic acid mutants have mutations in GmFAD3-1a, and the corresponding gene of M24 is also clarified that the mutation occurs at another GmFAD3-1b locus, which encode microsomal ω-3 fatty acid desaturase genes.2. We found that the addition of 20mM pyroglutamic acid to culture meda drastically improved the embryogenesis efficiency from soybean immature embryo and the addition of 0.2% polypeptone S was also effective for the embryo growth. Furthermore, we have developed three transgenic soybean lines of Japanese cultivar, Kyushu 126, by introducing EGFP gene under those conditions.3. We have successfully developed the transgenic rice with GmFAD3-1a gene which have improved the α- linolenic acid content of seeds over 10-fold higher than that of non-transgenic rice, have developed a novel RNAi vector for plant transformation, and it was clarified that these techniques were effective for the improvement of the soybean lipid using the transgenic technology.4. It has successfully cloned the genes (cDNA and genomic DNA) encoding diacylglycerol acyl transferase (DGAT) which could control the lipig composition (TAG/DAG ratio) and oil yield.