黄花蒿腺毛细胞中过表达AaADS基因显著提高青蒿素含量  

Overexpression of AaADS Gene Increases Growth of Glandular Trichomes of Artemisia annua and the Content of Artemisinin

作　　者：肖楠 张学文[1] 龙炎杏 陈金军[1] 谢心 赵燕[1] Xiao Nan;Zhang Xuewen;Long Yanxing;Chen Jinjun;Xie Xin;Zhao Yan(College of Bioscience and Biotechnology,Hunan Agricultural University,Changsha,410128)

机构地区：[1]湖南农业大学生物科学技术学院,长沙410128

出　　处：《分子植物育种》2021年第16期5389-5397,共9页Molecular Plant Breeding

基　　金：湖南省自然科学基金项目(2019JJ40123)资助。

摘　　要：为研究青蒿素合成的关键酶基因AaADS过表达对黄花蒿腺毛发育和青蒿素含量的影响,本研究根据GenBank收录的黄花蒿AaADS基因启动子和cDNA序列设计引物,采用同源克隆的方法从黄花蒿品种(428-A)中扩增出AaADS基因启动子和cDNA序列。构建GUS报告载体AaADSpro::GUS和植物表达载体AaADSpro::AaADS,利用农杆菌介导的叶盘转化法转化黄花蒿。通过对转基因植株叶片腺毛的GUS基因活性检测和不同组织器官AaADS基因RT-PCR半定量分析,以及过表达AaADS基因的植株叶片下表皮腺毛荧光显微观察、统计和植株青蒿素含量的测定,结果表明:AaADS基因能在黄花蒿腺毛细胞中高效表达;转基因植株中AaADS基因表达量明显高于对照,且在叶片组织表达量最高;转基因植株叶片腺毛细胞较对照植株明显增大,过表达AaADS基因植株中青蒿素含量达27.3 mg/g DW,比对照植株中青蒿素含量12 mg/g DW提高了2.3倍。本研究说明AaADS基因过表达能有效促进黄花蒿腺毛细胞的生长和青蒿素的生物合成,为选育高青蒿素含量的黄花蒿新品系提供可行性方法。This study aimed to investigate the effect of overexpression of AaADS, a key enzyme gene for artemisinin synthesis, on the development of Artemisia annua glandular trichomes and artemisinin content. The promoter and cDNA sequences of AaADS of Artemisia annua L were amplified using the homologous cloning method according to the sequence information available on the GenBank. Next, the GUS reporter vector AaADSpro::GUS and the plant expression vector AaADSpro::AaADS based the gene promoter were constructed and transformed into A. annua using Agrobacterium-mediated leaf disctransformation. GUS gene activity in the transgenic plant leaf glandular trichomes was determined, and AaADS expression in different tissues and organs was detected bysemi-quantitative-PCR concerning. In addition, the glandular trichomes of lower epidermis of leaves were observed and analyzed under a fluorescence microscope, and the content of artemisinin was determined. The results showed that the AaADS gene could be efficiently expressed in A.annua glandular trichome cells;the AaADS gene expression in transgenic plants was significantly higher than that in the control with the highest expression found in the leaf tissue;the transgenic plants presented significantly increased glandular trichome cells compared to the control plants. Artemisinin content in plants overexpressing AaADS gene reached27.3 mg/g DW, which was 2.3 times higher than that in control plants with 12 mg/g DW. The study indicated that the overexpression of AaADS gene could effectively promote the growth of Artemisia annua glandular hair cells and the biosynthesis of artemisinin, which provided a feasible method for breeding new Artemisia annua strains with high artemisinin content.

关 键 词：黄花蒿 青蒿素 AaADS 腺毛 

分 类 号：S567.219[农业科学—中草药栽培]