| 摘要: |
| 脱落酸(abscisic acid,ABA)激素是一类重要的生长调节物质,参与调控植物的多种生理过程。花青素(anthocyanins)是植物次生代谢产生的类黄酮化合物,对植物的生长发育和逆境胁迫响应有重要作用。该文以拟南芥(Arabidopsis thaliana)为研究对象,探讨ABA信号对花青素生物合成的调控功能和作用机制。结果表明:外源施加ABA显著提高野生型幼苗茎尖中花青素的积累。相一致的是,ABA能诱导某些与花青素合成相关的转录因子及合成酶基因的表达。遗传学分析发现,ABA诱导花青素合成部分依赖于MBW复合体中的核心转录因子,如TTG1、TT8及MYB75等。初步机制研究揭示,ABA信号途径中的bZIP类转录因子ABI5能与TTG1、TT8及MYB75等相互作用形成蛋白复合物。综上结果认为,ABA信号诱导拟南芥幼苗中花青素的积累,并可能通过ABI5与MBW复合体协同作用调控花青素的合成。 |
| 关键词: 拟南芥, 脱落酸, 花青素, ABI5转录因子, MBW复合体 |
| DOI：10.11931/guihaia.gxzw201902021 |
| 分类号:Q943 |
| 文章编号:1000-3142(2020)08-1169-12 |
| Fund project:国家自然科学基金(31670281)[Supported by the National Natural Science Foundation of China 31670281)]。 |
|
| Abscisic acid induces anthocyanin synthesis in Arabidopsis thaliana seedlings |
|
CHEN Junjie1, 2, MEI Song1, HU Yanru1*
|
|
1. CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy
of Sciences, Kunming 650223, China;2. University of Chinese Academy of Sciences, Beijing 100049, China
|
| Abstract: |
| Abscisic acid(ABA)is a critical phytohormone and widely modulates various biological processes in plants. Anthocyanins are flavonoids produced by plant secondary metabolism and play crucial roles in plant growth and stress responses. Recently, several transcription factors and synthetase genes involved in anthocyanins biosynthesis have been well studied; however, the upstream regulatory signals mediating their synthesis remain to be further explored. In this study, we taken Arabidopsis thaliana as the research object and investigated the function and mechanism of ABA in the control of anthocyanin biosynthesis. Phenotypic analysis showed that exogenous application of ABA significantly increased the accumulation of anthocyanins in the stem ends of wild-type A. thaliana seedlings. Consistently, ABA induced the expression of certain transcription factors and synthetase genes associated with anthocyanin synthesis. In addition, genetic analysis revealed that ABA-stimulated anthocyanin synthesis is partially dependent on core transcription factors in the MBW complex that positively regulates anthocyanin synthesis, such as TTG1, TT8, and MYB75. Preliminary mechanism studies revealed that the bZIP-type transcription factor ABI5 in the ABA signaling pathway physically interacts with TTG1, TT8 and MYB75 to form a protein complex. Taken together, this study shows that ABA signaling induces anthocyanin accumulation in A. thaliana seedlings and may regulate the synthesis of anthocyanins by synergizing the ABI5 with the MBW complex. |
| Key words: Arabidopsis thaliana, ABA, anthocyanin, ABI5 transcription factor, MBW complex |
