Regulation of DELLA Activity by Post-Translational Modifications and Complex Formation in Arabidopsis

拟南芥中翻译后修饰和复合物形成对 DELLA 活性的调节

• 批准号: 0923723
• 负责人: Tai-ping Sun
• 金额: $ 60万
• 依托单位: Duke University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-15 至 2013-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0923723&HistoricalAwards=false
• 关键词: Regulation; DELLA; Activity; Post; Translational

Gibberellin (GA) is an important plant growth hormone, which promotes seed germination, leaf expansion, stem elongation and flower development in higher plants. The dwarf cultivars of wheat and rice developed during the Green Revolution in the 60s remarkably increased the grain yields. Recent studies revealed that these cultivars are modified in their GA production or responses to GA, illustrating the important role of this hormone in regulating plant development and in agriculture. GA-promoted growth and development is modulated by DELLA proteins, which are major negative regulators (repressors) of GA responses. Recent work in the PI's laboratory (funded by NSF) has made transforming findings that the GA receptor directly targets DELLA for degradation. There is also evidence suggesting multiple layers of regulation on the DELLA protein activity. DELLA is a master growth repressor, which integrates not only the GA signal, but also other hormone signals as well as biotic and abiotic signals (such as light conditions, pathogens, cold and drought stresses). Although DELLA plays such a pivotal role in regulating plant growth, very little is known about how DELLA activity is regulated. Preliminary data support that protein modifications play important roles in modulating DELLA function. Future research in this project will elucidate the molecular mechanisms involved. Broader Impacts:DELLA proteins are functionally highly conserved in Arabidopsis and in many crop plants. For example, the semi-dwarf wheat cultivars, an essential component of the Green Revolution, contain mutations in the Rht loci that encode DELLA proteins. This study will likely to have a broader impact in improving quality of agricultural crops. In addition, a postdoctoral fellow and four undergraduate students will gain research experience in this project. The findings of this study will be incorporated into three undergraduate courses at Duke University. Students will learn to appreciate how the information gained from studies in a model plant system can be used to improve agriculture practice and benefit society.

赤霉素（Gibberellin， GA）是一种重要的植物生长激素，在高等植物中具有促进种子萌发、叶片扩张、茎伸长和花发育的作用。60年代绿色革命期间培育的小麦和水稻矮秆品种显著提高了粮食产量。最近的研究表明，这些品种的GA产量或对GA的反应都经过了修饰，说明了这种激素在调节植物发育和农业中的重要作用。GA促进生长发育是由DELLA蛋白调控的，DELLA蛋白是GA反应的主要负调控因子（阻遏因子）。PI的实验室（由NSF资助）最近的工作已经取得了转变性的发现，GA受体直接针对DELLA进行降解。也有证据表明，对DELLA蛋白活性有多层调控。DELLA是一种主要的生长抑制因子，它不仅整合了GA信号，还整合了其他激素信号以及生物和非生物信号（如光照条件、病原体、寒冷和干旱胁迫）。尽管DELLA在调节植物生长中起着如此关键的作用，但人们对DELLA活性是如何调节的知之甚少。初步数据支持蛋白质修饰在调节DELLA功能中起重要作用。本项目未来的研究将进一步阐明其分子机制。更广泛的影响：DELLA蛋白在拟南芥和许多作物植物中功能高度保守。例如，作为绿色革命重要组成部分的半矮秆小麦品种，在编码DELLA蛋白的Rht位点中含有突变。这项研究可能会对提高农作物质量产生更广泛的影响。此外，一名博士后和四名本科生将在该项目中获得研究经验。这项研究的结果将被纳入杜克大学的三门本科课程。学生将学会欣赏从模式植物系统研究中获得的信息如何用于改善农业实践和造福社会。