过量表达棉花GDSL脂肪酶提高甘蓝型油菜油脂含量的研究

GDSL脂肪酶作为一种脂质水解酶具有广泛的底物特异性,在植物的油脂代谢、生长发育等众多生理过程中发挥着重要作用。利用RT-PCR技术从发育的陆地棉种子中克隆得到棉花的GDSL脂肪酶基因的cDNA,该基因开放读码框为1 068 bp,编码含有356个氨基酸的蛋白质。对棉花种子发育不同时期进行半定量PCR分析的结果表明,在种子发育15~20 d时,GhGLIP基因的表达量较高。将该基因构建到真核表达载体pCAMBIA2300中,转入农杆菌GV3101后转化甘蓝型油菜野油19,通过筛选和鉴定获得转基因阳性油菜株系。转基因油菜的GDSL脂肪酶活力获得了显著提高,转基因油菜种子的油脂含量比野生型油菜提高了8.68%,提高比率为24.3%。

Overexpression of a Cotton GDSL Lipase Increases the Oil Content of Brassica napus L.

GDSL lipase (GLIP), as a lipid hydrolase with broad substrate specificity, exists in plant tissues widespreadly, and plays important roles in lipid metabolism, plant growth and development and many other physiological processes. In this study, a cotton GDSL lipase named GhGLIP, was isloated from cotton ovules using RT-PCR method. The full open reading frame was 1068 bp containing a protein of 356 amino acids. Semi-quantitative PCR analysis of different cotton ovule development periods showed that GhGLIP gene expressed with higher values in 15-20 d ovules. The plant overexpression vector pCAMBIA2300-GhGLIP was obtained and transformed into Brassica napus L. (wild-oil 19) by Agrobacterium mediated method. Transgenic plants were obtained after screening and identification with a significant promotion of GDSL lipase enzyme activity, and the oil content of transgenic Brassica napus seeds was notablely enhanced with 8.68% higher and a increase ratio of 24.3% than wide-type.