Plastidic phosphate transport and plant biomass allocation

质体磷酸盐运输和植物生物量分配

• 批准号: 0956486
• 负责人: Wayne Versaw
• 金额: $ 42.9万
• 依托单位: Texas A&M Research Foundation
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-02-15 至 2014-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0956486&HistoricalAwards=false
• 关键词: Plastidic; phosphate; transport; plant; biomass

Plastids are a defining feature of plant cells. These diverse organelles are the sites of a wide array of essential processes that include photosynthesis and the subsequent partitioning of carbon between sugars for immediate use throughout the plant, and starch for temporary storage that is reclaimed during the night. Phosphate concentrations strongly influence these processes, but understanding of the transport proteins needed to coordinate plastidic phosphate levels with environmental and metabolic conditions is incomplete. The objectives of this project are to determine the transport mechanism and physiological role of phosphate transporters that reside in either chloroplasts or non-photosynthetic plastids of the model plant Arabidopsis thaliana. Loss-of-function mutants for these transporters display unique growth and metabolic phenotypes that suggest distinct roles. Notably, a mutant for a root plastid transporter exhibits increased cell proliferation in leaves with a corresponding increase in leaf biomass. Grafting studies combined with genetic and biochemical studies will be used to test the hypothesis that carbon allocation between root and shoot tissues influences mitotic activity in leaves. This project will provide new insight into how plants integrate phosphate and carbon metabolism at the cellular level to control the physiology of photosynthetic and non-photosynthetic tissues. Moreover, these studies may have practical implications for agriculture. Graduate and undergraduate students will receive multidisciplinary research training, formal teaching opportunities, and will participate in the development and implementation of undergraduate biology education workshops.

质体是植物细胞的一个决定性特征。这些不同的细胞器是一系列重要过程的场所，包括光合作用和随后在整个植物中立即使用的糖和在夜间回收的临时储存淀粉之间的碳分配。磷酸盐浓度强烈影响这些过程，但对协调环境和代谢条件下塑性磷酸盐水平所需的转运蛋白的了解尚不完整。本项目的目的是确定模式植物拟南芥叶绿体或非光合质体中磷酸盐转运体的转运机制和生理作用。这些转运体的功能缺失突变体显示出独特的生长和代谢表型，表明其具有不同的作用。值得注意的是，一个根质体转运体突变体在叶片中表现出细胞增殖增加，叶片生物量相应增加。嫁接研究将结合遗传和生化研究来验证根和茎组织之间的碳分配影响叶片有丝分裂活性的假设。该项目将为植物如何在细胞水平上整合磷酸盐和碳代谢以控制光合和非光合组织的生理提供新的见解。此外，这些研究可能对农业有实际意义。研究生和本科生将接受多学科的研究培训，正式的教学机会，并将参与本科生生物学教育研讨会的制定和实施。