nature

当前位置: Cell » Research Journals » Mol Plant:厦门大学欧阳鑫昊研究组揭示水稻光周期调控开花新机制

Mol Plant:厦门大学欧阳鑫昊研究组揭示水稻光周期调控开花新机制

摘要 : 2017年5月23日,国际著名学术杂志《Cell》子刊《Molecular Plant》杂志在线发表了厦门大学生命科学学院欧阳鑫昊副教授课题组题为“The DTH8-Hd1 module mediates day length dependent regulation of rice flowering”的研究论文

2017年5月23日,国际著名学术杂志《Cell》子刊《Molecular Plant》杂志在线发表了厦门大学生命科学学院欧阳鑫昊副教授课题组题为“The DTH8-Hd1 module mediates day length dependent regulation of rice flowering”的研究论文,报道了水稻光周期调控开花的最新研究进展。光周期调控开花是植物开花调控的重要方式,尤其是对于作物适应环境、引种、制种和产量都至关重要。水稻是典型的短日照作物,在短日照诱导开花,而长日照则会抑制开花。因此,水稻被作为研究作物适应不同光周期环境的理想模式植物。博士研究生杜安平为论文的第一作者,通讯作者为欧阳鑫昊副教授。

Hd1是水稻光周期开花网络的核心元件。与拟南芥的同源基因CO在长日照下正调控FT的转录不同,水稻中,Hd1调控FT同源基因Hd3a的转录活性能被光周期改变。在短日照下,Hd1激活Hd3a的表达。相反,在长日照下,Hd1抑制Hd3a的表达。目前,光周期调控Hd1功能转换的分子机制依然未知。本研究中,作者证明Hd1在长日照对Hd3a的转录抑制是依赖于一个水稻的长日照开花抑制因子DTH8。当DTH8失去功能时,Hd1能够在长日照展现出对Hd3a的转录激活活性。本文进一步揭示DTH8可以和Hd1直接发生相互作用并且结合到Hd3a的启动子区域,当DTH8-Hd1复合体结合到Hd3a的启动子时,H3K27me3水平会显著增加,从而发生转录抑制;相反,当DTH8失去功能时,Hd1单独的存在于Hd3a的启动子时,H3K27me3水平会显著下降,从而发生转录激活。最终,本文揭示了DTH8-Hd1复合体在长日照下抑制Hd3a转录的分子机制,部分的解析了Hd1在不同光周期条件下功能转换的分子机理。

原文链接:

The DTH8-Hd1 module mediates day lengthdependent regulation of rice flowering

原文摘要:

Photoperiodic flowering is one of the most important pathways to govern flowering in rice (Oryza sativa), in which Heading date 1 (Hd1), an ortholog of the ArabidopsisConSTANS gene, encodes a pivotal regulator. Hd1 promotes flowering under short-day conditions but represses flowering under long-day conditions by regulating the expression of Heading date 3a (Hd3a), the rice FLOWERING LOCUS T (FT) ortholog. However, the molecular mechanism by which Hd1 reverses its activity in response to day length is largely unknown. Here, we demonstrate that the repression of flowering in LD mediated by Hd1 is dependent on the transcription factor DAYS TO HEADING 8 (DTH8). Loss of DTH8 function results in the activation of Hd3a by Hd1, leading to early flowering. We also show that Hd1 directly interacts with DTH8 and that the formation of the DTH8-Hd1 complex is necessary for the transcriptional repression of Hd3a by Hd1 in LD. We thus detected a switch in function of Hd1 mediated by DTH8 in LD rather than in SD. Further, we reveal that DTH8 associates with the Hd3a promoter to modulate the level of trimethylated H3K27 at the Hd3a genomic locus. H3K27 trimethylation increases at Hd3a in the presence the DTH8-Hd1 complex, while Hd1 attenuates the H3K27me3 level in Hd3a when DTH8 function is lost. Therefore, our findings establish that, in response to day length, DTH8 plays a critical role in mediating Hd1 regulation of Hd3a transcription through the DTH8-Hd1 module to shape epigenetic marks in photoperiodic flowering.

来源: Molecular Plant 浏览次数:0

我们欢迎生命科学领域研究成果、行业信息、翻译原创、实验技术、采访约稿。-->投稿

RSS订阅 | 生物帮 | 粤ICP备11050685号-3 ©2011-2014 生物帮 Cell  All rights reserved.