FAT1转基因系祖公牛选育及其扩繁研究

Breeding and Propagation of FAT1 Transgenic Ancestral Bull

n-3多不饱和脂肪酸(n-3 polyunsaturated fatty acids,n-3 PUFAs)是人体必需脂肪酸,对多种疾病有抑制作用。利用超数排卵与胚胎移植技术(superovulation and embryo transfer,MOET)对FAT1转基因牛进行了扩繁,并对F_(1)代牛进行了生长指标测定与遗传稳定性分析,在此基础上确定了系祖公牛ZK005;用ZK005的冻精经人工授精生产F2代,并对其进行生长指标测定、遗传稳定性分析和血液生化指标检测。结果显示,原代牛的MOET扩繁效果良好,获得了8头FAT1基因阳性F_(1)代牛;F_(1)代牛生长指标与野生型牛无显著差异;外源基因稳定整合,n-3 PUFAs含量显著提高,n-6多不饱和脂肪酸/n-3多不饱和脂肪酸(n-6 polyunsaturated fatty acids/n-3polyunsaturated fatty acids,n-6/n-3)比值显著降低;F_(1)代牛各组织中n-3 PUFAs含量显著提高,其中肌肉中提高最明显。从F_(1)代牛中选择备用系祖公牛ZK005,其精液冷冻后活力达40%,经人工输精获得F2代牛12头,F2代牛生长发育与血液生化指标整体上与野生型牛无显著差异。以上研究表明,利用转基因技术选育FAT1转基因牛,可培育富含n-3 PUFAs的转基因牛新品系(种),提高牛肉、奶中n-3 PUFAs含量,且FAT1基因在F_(1)和F2代牛中均能稳定有效表达,对转基因牛的健康无不利影响,可为人类提供更营养的食品。

n-3 polyunsaturated fatty acids(n-3 PUFAs)are essential fatty acids for human health and can inhibit many diseases. Using transgenic technology to produce FAT1 transgenic cattle can improve the content of n-3 PUFAs in beef and milk,and provide healthy food for human. In this study,after propagation of FAT1 transgenic cattle through superovulation and embryo transfer(MOET)technique,the growth index and genetic stability of F_(1)generation cattle were tested. After that,ZK005 bull was determined as ancestry based on the analysis. The Fgeneration was produced by artificial insemination with frozen semen of ZK005,and its growth indexes,genetic stability and blood biochemical indexes were measured. The results showed that 8 FAT1 gene positive F_(1)cattle were obtained. There was no significant difference in growth index between F_(1)and wild-type cattle. The content of n-3 PUFAs increased significantly and the ratio of n-6/n-3 PUFAs decreased significantly. The content of n-3 PUFAs in various tissues significantly increased,especially in muscles. Total of 12 Fgeneration cattle,were obtained by artificial insemination. There was no significant difference in growth and development and blood biochemical indexes between Fgeneration cattle and wild-type cattle as a whole,while the above research showed that breeding FAT1 transgenic cattle with transgenic technology could cultivate new transgenic cattle strains(species)rich in n-3 PUFAs,improved the content of n-3 PUFAs in beef and milk,and FAT1 gene could be stably and effectively expressed in Fand Fgeneration cattle,which had no adverse impact on the health of transgenic cattle and could provide more nutritious food for human beings.