Liquid-liquid phase separation around a membrane: Investigating the assembly of the pyrenoid around the thylakoid membrane in Chlamydomonas reinhardtii

膜周围的液-液相分离：研究莱茵衣藻类囊体膜周围蛋白核的组装

• 批准号: 456013262
• 负责人: Dr. Philipp Girr
• 金额: --
• 依托单位: University of York
• 依托单位国家: 德国
• 项目类别: WBP Fellowship
• 财政年份: 2021
• 资助国家: 德国
• 起止时间: 2020-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/456013262?language=en
• 关键词: Liquid; liquid; phase; separation; around

It is currently a major challenge for humankind to ensure global food security for a growing world population and to fulfil the demands of carbon-neutral energy sources in times of climate change. Critical to addressing this challenge is an increase in crop yields to ensure that increases in food and biofuel production are achieved without further agriculture driven ecosystem loss. One promising approach that is predicted to increase crop yields by up to 60% is the engineering of an algal CO2 concentrating mechanism (CCM) into crop plants. The heart of the algal CCM is a liquid-liquid phase separated organelle within the chloroplast, the pyrenoid. The pyrenoid contains most of the cells Rubisco and is constantly supplied with CO2 by active transport mechanisms. CO2 enters the pyrenoid ultimately through specialised regions of the thylakoid membrane that transverse the pyrenoid, the so-called thylakoid tubules. Even though the thylakoid tubules are important for the CO2 supply and the exchange of metabolites between the pyrenoid and the chloroplast stroma, we basically know nothing about the interaction between the Rubisco containing matrix of the pyrenoid and thylakoid tubules and the biogenesis of the thylakoid tubules. In the proposed project, I will investigate these knowledge gaps in the model organism Chlamydomonas reinhardtii. Through literature and bioinformatic analysis I have identified candidate proteins that could act as tether proteins between the thylakoid tubules and the pyrenoid matrix, and others that are potentially involved the biogenesis of the thylakoid tubules. In the proposed project, I will biochemically analyse the function of those proteins both in vivo and in vitro to elucidate their function. Furthermore, I will use the identified underlying fundamental principles of pyrenoid assembly to guide the engineering of a synthetic CCM system in vitro. Together, the data obtained in the proposed project will guide the engineering of a pyrenoid in crops to increase yields.

确保不断增长的世界人口的全球粮食安全并满足气候变化时期对碳中和能源的需求是当前人类面临的重大挑战。应对这一挑战的关键是提高农作物产量，以确保在不进一步造成农业驱动的生态系统损失的情况下实现粮食和生物燃料产量的增加。一种有望将农作物产量提高高达 60% 的方法是在农作物中设计藻类二氧化碳浓缩机制 (CCM)。藻类 CCM 的核心是叶绿体内的液-液相分离细胞器，即类核蛋白。蛋白核含有大部分 Rubisco 细胞，并通过主动运输机制持续提供二氧化碳。二氧化碳最终通过横穿蛋白核的类囊体膜的特殊区域（即所谓的类囊体小管）进入蛋白核。尽管类囊体小管对于核糖体和叶绿体基质之间的 CO2 供应和代谢物交换很重要，但我们基本上对类囊体小管和类囊体小管的含 Rubisco 基质之间的相互作用一无所知。在拟议的项目中，我将研究模式生物莱茵衣藻中的这些知识差距。通过文献和生物信息学分析，我已经确定了可以充当类囊体小管和蛋白核基质之间的系链蛋白的候选蛋白，以及其他可能参与类囊体小管生物发生的蛋白。在拟议的项目中，我将在体内和体外对这些蛋白质的功能进行生化分析，以阐明它们的功能。此外，我将使用已确定的核糖核组装的基本原理来指导体外合成 CCM 系统的工程设计。总之，拟议项目中获得的数据将指导作物中核蛋白的工程设计以提高产量。