摘要
γ-亚麻酸(GLA)是人体和动物饮食中具有营养作用的重要的多烯不饱和脂肪酸,在大多数油料作物种子中不含有GLA,而含有其前体物亚油酸。△6-脂肪酸脱氢酶可将亚油酸转化为γ-亚麻酸,为了能够在传统的油料作物大豆中产生GLA,将从深黄被孢霉中克隆的△6-脂肪酸脱氢酶基因,与植物表达载体pBIl21连接,构建了重组质粒pBIM16,采用农杆菌介导的大豆子叶节转化系统,成功地将该基因导入到栽培大豆吉林47品种中,获得一批转基因植株。经PCR检测和Southern杂交分析,证明外源基因已导入并整合到大豆的基因组中。通过气相色谱(GC)对大豆种子进行脂肪酸成分分析,结果表明,产生了GLA,其含量最高可达36.585%。将高GLA的转基因大豆油口服给药,结果表明,其对小鼠S180肉瘤、肝癌H22和Ehrlich癌实体型的抑瘤率分别为32.63%、31.91%和34.34%。其肿瘤抑制率均>30%,与对照组比较有显著差异(p<0.01),表现初步的抗肿瘤作用。
γ-linolenic acid (GLA, C18:3△6.9.12 ) is nutritional and important polyunsaturated fatty acid in human and animal diets. Vast majority of oilseed crops do not produce GLA, but linoleic acid (LA, C18:2△9.12) as its substrate.△6--fatty acid desaturase(D6D) is the rate-limiting enzyme in the production of GLA. It can convert from linoleic acid to linolenic acid. The A -fatty acid desaturase gene from Mortitieralla isabellina was transferred into cultivars Jilin47 soybean successfully with Agrobacterium-cotylendon node transformation system. PCR and Southern hybridization analysis from the transferred gene plants proved that foreign gene were transferred and integrated into soybean genome. Total fatty acids extracted from the positive transgenic soybean were analyzed by gas chromatography (GC) of methyl esters to confirm the transgenic soybean containing a functional △6-fatty acid desaturase gene. Among the seeds under detection, the highest content of GLA amounts to 36.585% of the total fatty acids. The presence of GLA indicates that the △6-fatty acid desaturase gene from Mortitieralla isabellina were expressed in transgenic soybean. The tumor inhibitive rate of the transgenic soybean oil administrated orally to Sarcoma 180 tumor-bearing mice is 32.63% , H22 tumor-bearing mice is 31.91% and Ehrlich tumor-bearing mice is 34.34% . The results suggest that the transgenic soybean oil could inhibit the growth of S180, H22 and Ehrlich tumor in mice, which the inhibitive rate is more than 30% ,and the difference is significant(p <0.01)when compared with the tumor control group.
出处
《中国生物工程杂志》
CAS
CSCD
北大核心
2005年第7期92-97,共6页
China Biotechnology
