CAPP: Combining Algal and Plant Photosynthesis

CAPP：结合藻类和植物光合作用

基本信息

批准号：
1105617
负责人：
Martin Jonikas
金额：
$ 71.99万
依托单位：
Carnegie Institution of Washington
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2011
资助国家：
美国
起止时间：
2011-03-15 至 2015-02-28
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1105617&HistoricalAwards=false
关键词：
CAPP Combining Algal Plant Photosynthesis

项目摘要

There is a clear need to increase crop productivity to feed our growing population. The enzyme RuBisCO is critical for the fixation of carbon dioxide into sugars in all plants, but its low efficiency makes it a major bottleneck in photosynthesis. To compensate for RuBisCO's low efficiency, plants with a photosynthetic process known as "C-3" (such as rice and wheat) devote a large fraction of their resources to producing the RuBisCO protein, which constitutes up to 50% of the total protein in their leaves. Unlike C3 plants, many algae have developed a means to drastically reduce the amounts of RuBisCO protein needed for efficient photosynthesis, by using a biophysical carbon concentrating mechanism (CCM). The CCM increases the carbon dioxide concentration within a subcellular compartment called the pyrenoid where RuBisCO is located, thus enhancing carbon dioxide assimilation with less RuBisCO protein.The ambitious goal of this program is to transfer the CCM from the green alga Chlamydomonas to the model C3 plant Arabidopsis, thus improving rates of carbon dioxide assimilation. The program will use a cutting-edge genome-wide screen to discover novel components of the algal CCM, including pyrenoid components. The physiological functions, localizations and physical interactions of known and newly-discovered components will be characterized by molecular and cell biological approaches, including electron microscopy and mass spectrometry. A modified RuBisCO will be developed and inserted into Arabidopsis to enable formation of a pyrenoid-like organelle. Known components and, progressively, key newly-discovered components, will be transferred to Arabidopsis and their impact on photosynthesis will be assessed. The process will be guided and supported by the development of advanced computational models.This transformative program represents a leap forward towards improving the photosynthetic efficiency of C3 crop plants, by introduction of a biophysical CCM from green algae. Additionally, the research will provide a much clearer molecular definition of the algal CCM, which is a fundamentally important yet poorly understood biological process. The research will provide undergraduate students opportunities to learn from a broad base of biological research.

显然需要提高作物生产力来养活不断增长的人口。 RuBisCO 酶对于所有植物将二氧化碳固定为糖至关重要，但其低效率使其成为光合作用的主要瓶颈。为了弥补RuBisCO的低效率，具有被称为“C-3”光合作用过程的植物（例如水稻和小麦）将其大部分资源用于生产RuBisCO蛋白质，该蛋白质占植物总蛋白质的50%他们的叶子。与 C3 植物不同，许多藻类已经开发出一种方法，通过使用生物物理碳浓缩机制 (CCM)，大幅减少高效光合作用所需的 RuBisCO 蛋白的量。 CCM 增加了 RuBisCO 所在的核糖体亚细胞区室中的二氧化碳浓度，从而用更少的 RuBisCO 蛋白增强二氧化碳同化。该计划的宏伟目标是将 CCM 从绿藻衣藻转移到模型 C3 植物拟南芥，从而提高二氧化碳同化率。该计划将使用尖端的全基因组筛选来发现藻类 CCM 的新成分，包括类核成分。已知和新发现的成分的生理功能、定位和物理相互作用将通过分子和细胞生物学方法（包括电子显微镜和质谱法）进行表征。将开发改良的 RuBisCO 并将其插入拟南芥中，以形成类蛋白核细胞器。已知的成分以及逐渐新发现的关键成分将被转移到拟南芥中，并评估它们对光合作用的影响。这一过程将得到先进计算模型开发的指导和支持。这一变革性计划通过引入来自绿藻的生物物理 CCM，代表着提高 C3 作物光合作用效率的飞跃。此外，该研究将为藻类 CCM 提供更清晰的分子定义，这是一个极其重要但人们了解甚少的生物过程。该研究将为本科生提供从广泛的生物学研究基础中学习的机会。