Deciphering components of the nitrogen limitation response in arabidopsis

破译拟南芥氮限制反应的组成部分

• 批准号: 38039-2009
• 负责人: Rothstein, Steven
• 金额: $ 5.17万
• 依托单位: University of Guelph
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2011
• 资助国家: 加拿大
• 起止时间: 2011-01-01 至 2012-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=474793
• 关键词: Deciphering; components; nitrogen; limitation; response

Considerable stress will be placed on world-wide crop production due to an increased human population, an increase in the crops used per person and environmental issues. Besides water availability, nitrogen is the major limiting factor in crop production. To develop crops that can use nitrogen more efficiently, we must understand the role of genotype on its acquisition and use. Therefore, it is essential to understand the role of signaling and regulatory mechanisms that control nitrogen metabolism under nitrogen limitation conditions. In this proposal, the studies will focus on molecular genetic and genomic studies in Arabidopsis. First, we wish to understand in much greater detail how a plant senses nitrogen limitation. Second, we wish to target a set of transcription factors (GNC and CGA-1) for which we have considerable evidence for their role in controlling the carbon-nitrogen balance under nitrogen limitation. Further, over-expression of these genes can lead to an enhanced growth phenotype in Arabidopsis and rice. We identified the nitrogen limitation adaptability (nla) gene as a key component for the adaptation of Arabidopsis plant grown under limited nitrogen conditions. We will use a variety of techniques including genetic, biochemical and physiological approaches to identify additional genes that are essential for the nitrogen limitation adaptability pathway. In addition, we will delineate the targets of GNC and CGA-1 transcription factors that will allow us to further understand their roles. Finally, we will do a metabolome and transcriptome analysis of the response of Arabidopsis to limiting nitrogen both in wild-type and in the various mutant and over-expression lines that we have developed or will develop in the future. The long term goal is to use this information to target genes in crop plants to develop genetic lines that yield better under field conditions where less nitrogen fertilizer is used. This, in turn, would significantly improve both the economic and environmental sustainability of crop production.

由于人口增加、人均农作物使用量增加以及环境问题，世界范围内的农作物生产将面临相当大的压力。 除了水的可用性之外，氮是作物生产的主要限制因素。 为了开发能够更有效地利用氮的作物，我们必须了解基因型对其获取和利用的作用。 因此，了解氮限制条件下控制氮代谢的信号和调节机制的作用至关重要。 在该提案中，研究将集中于拟南芥的分子遗传学和基因组研究。 首先，我们希望更详细地了解植物如何感知氮限制。 其次，我们希望针对一组转录因子（GNC 和 CGA-1），我们有大量证据证明它们在氮限制下控制碳氮平衡方面的作用。 此外，这些基因的过度表达可以导致拟南芥和水稻的生长表型增强。 我们确定氮限制适应性（nla）基因是拟南芥植物适应在有限氮条件下生长的关键组成部分。我们将使用包括遗传、生化和生理学方法在内的各种技术来识别对于氮限制适应性途径至关重要的其他基因。 此外，我们将描述 GNC 和 CGA-1 转录因子的靶标，这将使我们能够进一步了解它们的作用。 最后，我们将对野生型以及我们已经开发或将来开发的各种突变体和过表达系中拟南芥对限制氮的反应进行代谢组和转录组分析。 长期目标是利用这些信息来靶向农作物中的基因，以开发在使用较少氮肥的田间条件下产量更高的遗传系。 反过来，这将显着提高作物生产的经济和环境可持续性。