Crosstalk between gibberellin and other signaling molecules in the regulation of seed dormancy

赤霉素与其他信号分子在种子休眠调节中的串扰

• 批准号: RGPIN-2016-05899
• 负责人: Ayele, Belay
• 金额: $ 2.55万
• 依托单位: University of Manitoba
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=644351
• 关键词: Crosstalk; between; gibberellin; other; signaling

Gibberellin (GA) is among the plant-produced signaling compounds that influence a wide range of developmental processes at very low concentrations, usually described as “plant hormones”. GA controls the ability of seeds to germinate, or to remain dormant, and this is mediated by the amount of GA present in the seed and seed response to GA. Excess amounts of GA in seeds, or high seed response to the GA, triggers premature germination. Conversely, seeds with low amounts of GA or low response to GA, fail to germinate and remain dormant; and dormancy loss is often associated with increased seed GA level and response. Dormancy control by GA is also mediated by its crosstalk with other signaling molecules that take part in the regulation of seeds' ability to germinate or not, such as jasmonate (JA) and reactive oxygen species (ROS). Seeds employ different strategies to mediate the regulation of GA level and response by other signaling molecules or vice versa, and thereby maintain or lose their state of dormancy. Several of these strategies and the associated regulatory elements have been identified in the seeds of dicots, and understanding this phenomenon has been lagging in monocots, particularly in cereals such as wheat. The overall goal of my research program is to understand how plant hormones regulate developmental processes in sufficient detail to enable genetic manipulation for enhancing crop yield and quality. Within this context, the specific objective of the proposed research is to identify new strategies used by wheat seeds to mediate the control of GA level and response by JA or ROS and vice versa, and thereby control their developmental switch between dormancy and germination. The outcomes of this study not only advance our knowledge of how dormancy is regulated by crosstalk between GA and ROS or JA but also provide new avenues to further increase our understanding of the strategies underlying hormonal control of seed dormancy and germination. The findings of this work will also provide powerful tools for improving the success of seed germination and seedling establishment under diverse environmental conditions and the tolerance of maturing seeds to preharvest sprouting, a serious problem in the production of wheat, thus enhancing yield and quality. Furthermore, this research will train 4 Ph.D., 1 M.Sc. and 5 undergraduate students with a wide range of skills highly valued in the area of plant biology, making the trainees well-positioned to succeed in their career goals while contributing to Canada's need for highly qualified plant biologists.

赤霉素(GA)是植物产生的信号化合物之一，在很低的浓度下影响广泛的发育过程，通常被称为“植物激素”。GA控制种子萌发或休眠的能力，这是通过种子中GA的含量和种子对GA的反应来调节的。种子中GA含量过多，或种子对GA的反应较高，都会引发早熟萌发。相反，GA含量低或对GA的响应低的种子不能萌发并保持休眠；休眠的丧失通常与种子GA水平和响应的增加有关。GA对休眠的控制也是通过与其他参与调节种子萌发能力的信号分子的串扰来实现的，如茉莉酸(JA)和活性氧(ROS)。种子采用不同的策略来调节GA水平和其他信号分子的响应，反之亦然，从而维持或解除其休眠状态。在双子叶植物的种子中已经确定了其中的几种策略和相关的调控元件，对这种现象的理解在单子叶植物中一直滞后，特别是在小麦等谷物中。我的研究计划的总体目标是充分详细地了解植物激素如何调节发育过程，以实现提高作物产量和质量的遗传操作。在这一背景下，本研究的具体目标是确定小麦种子所使用的新策略，以中介JA或ROS对GA水平和反应的控制，反之亦然，从而控制其在休眠和萌发之间的发育转换。这项研究的结果不仅加深了我们对GA和ROS或JA之间的串扰如何调节休眠的了解，而且也为进一步了解激素控制种子休眠和萌发的策略提供了新的途径。这项工作的结果还将为提高不同环境条件下种子萌发和成苗的成功率以及成熟种子对小麦生产中的严重问题--穗发芽的耐受性提供有力的工具，从而提高产量和质量。此外，本研究还将培养4名博士和1名硕士。以及5名在植物生物学领域拥有广泛技能的本科生，使学员处于有利地位，能够成功实现他们的职业目标，同时为加拿大对高素质植物生物学家的需求做出贡献。