AaMYB1 and its orthologue AtMYB61 affect terpene metabolism and trichome development in Artemisia annua and Arabidopsis thaliana
AaMYB1 and its orthologue AtMYB61 affect terpene metabolism and trichome development in Artemisia annua and Arabidopsis thaliana
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DOI：
10.1111/tpj.13509
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发表时间：
2017-05-01
期刊：
影响因子：
7.2
通讯作者：
Pelaz, Soraya
中科院分区：
文献类型：
--
作者：
Matias-Hernandez, Luis;Jiang, Weimin;Pelaz, Soraya
从黄花蒿中分离出的有效抗疟疾药物青蒿素（artemisinin， AN）价格相对昂贵，因为黄花蒿中AN的含量较低，仅在腺毛状体中合成。因此，对黄花蒿进行基因工程改造是提高黄花蒿产量最有希望的途径之一。在这项工作中，AaMYB1转录因子已被鉴定和表征。当AaMYB1在黄花草中过度表达时，无论是仅在毛状体中还是在整个植物中，必需的AN生物合成基因也会过度表达，从而显着增加AN的量。AaMYB1组成型过表达的蒿表现出更多的毛状体。为了研究AaMYB1在毛状体发育和其他可能相关的生物学过程中的作用，AaMYB1在拟南芥中过表达。为了支持我们在拟南芥中的发现，从该模式植物中鉴定出AaMYB1同源物AtMYB61，并对AtMYB61突变体进行了表征。AaMYB1和AtMYB61均影响拟南芥毛状体形成、根系发育和气孔孔径。分子分析表明，两个关键的毛状体激活基因在atmyb61突变株和AaMYB1过表达株中表达错误。此外，AaMYB1和AtMYB61对这两个物种的赤霉素（GA）的生物合成和降解也是必不可少的，它们积极影响将GA(9)转化为生物活性GA(4)的酶的表达，以及参与GA降解的酶的表达(4)。总之，这些结果确定了AaMYB1/AtMYB61是连接重要生物合成过程的分子网络的关键组成部分，并揭示了其通过基因工程生产AN的潜在价值。
The effective anti-malarial drug artemisinin (AN) isolated from Artemisia annua is relatively expensive due to the low AN content in the plant as AN is only synthesized within the glandular trichomes. Therefore, genetic engineering of A. annua is one of the most promising approaches for improving the yield of AN. In this work, the AaMYB1 transcription factor has been identified and characterized. When AaMYB1 is overexpressed in A. annua, either exclusively in trichomes or in the whole plant, essential AN biosynthetic genes are also overexpressed and consequently the amount of AN is significantly increased. Artemisia AaMYB1 constitutively overexpressing plants displayed a greater number of trichomes. In order to study the role of AaMYB1 on trichome development and other possibly connected biological processes, AaMYB1 was overexpressed in Arabidopsis thaliana. To support our findings in Arabidopsis thaliana, an AaMYB1 orthologue from this model plant, AtMYB61, was identified and atmyb61 mutants characterized. Both AaMYB1 and AtMYB61 affected trichome initiation, root development and stomatal aperture in A. thaliana. Molecular analyses indicated that two crucial trichome activator genes are misexpressed in atmyb61 mutant plants and in plants overexpressing AaMYB1. Furthermore, AaMYB1 and AtMYB61 are also essential for gibberellin (GA) biosynthesis and degradation in both species by positively affecting the expression of the enzymes that convert GA(9) into the bioactive GA(4) as well as the enzymes involved in the degradation of GA(4). Overall, these results identify AaMYB1/AtMYB61 as a key component of the molecular network that connects important biosynthetic processes, and reveal its potential value for AN production through genetic engineering.