Institute of Genetics and Development Biology, Chinese Academy of Sciences, Beijing, 100101, China.
Plant Cell Rep. 2014 May;33(5):683-96. doi: 10.1007/s00299-014-1578-7. Epub 2014 Mar 26.
Brassinosteroids (BRs) are a group of steroid phytohormones with wide-ranging biological activity. Genetic, genomic and proteomic studies have greatly advanced our understanding of BR signaling in Arabidopsis and revealed a connected signal transduction pathway from the cell surface receptor kinase BRASSINOSTEROID-INSENSITIVE1 (BRI1) and BRI1-ASSOCIATED RECEPTOR KINASE 1 (BAK1) to the BRASSINAZOLE-RESISTANT1 (BZR1) family of transcription factors and their targets mediating physiological functions. However, compared with the dicot model plant Arabidopsis, much less is known about BR signaling in rice, which is a monocot. In this review, we provide an update on the progress made by BR studies in rice and discuss how BR regulates various important agronomic traits to determine rice grain yield. Specifically, we discuss the function of novel components including LEAF AND TILLER ANGLE INCREASED CONTROLLER (LIC), DWARF and LOW-TILLERING (DLT), DWARF1 (D1) and TAIHU DWARF1 (TUD1) in rice BR signaling, and provide a rice BR-signaling pathway model that involves a BRI1-dependent pathway as well as a G-protein α subunit-mediated signaling pathway. The recent significant advances in our understanding of BR-mediated molecular mechanisms underlying agronomic traits will be of great help for rice molecular breeding.
油菜素甾醇（BRs）是一类具有广泛生物学活性的甾体植物激素。遗传、基因组和蛋白质组学研究极大地促进了我们对拟南芥 BR 信号转导的理解，并揭示了从细胞表面受体激酶油菜素甾醇不敏感 1（BRI1）和 BRI1 相关受体激酶 1（BAK1）到 BRASSINAZOLE-RESISTANT1（BZR1）家族转录因子及其介导生理功能的靶标的连接信号转导途径。然而，与双子叶模式植物拟南芥相比，人们对单子叶植物水稻中的 BR 信号转导知之甚少。在这篇综述中，我们提供了 BR 在水稻中研究进展的最新情况，并讨论了 BR 如何调节各种重要的农艺性状来决定水稻的产量。具体来说，我们讨论了包括 LEAF AND TILLER ANGLE INCREASED CONTROLLER（LIC）、DWARF 和 LOW-TILLERING（DLT）、DWARF1（D1）和 TAIHU DWARF1（TUD1）在内的新成分在水稻 BR 信号转导中的功能，并提供了一个涉及 BRI1 依赖性途径和 G 蛋白 α 亚基介导的信号转导途径的水稻 BR 信号转导途径模型。我们对 BR 介导的农艺性状分子机制的理解的最新重大进展将对水稻分子育种有很大帮助。
