Crops & Soil - Regulation of Rubisco in a synthetic pyrenoid-like condensate expressed in rice

核酮糖1,5-二磷酸羧化酶/加氧酶（Rubisco）是植物二氧化碳同化的驱动力。尽管Rubisco很重要，但它是一种缓慢且容易出错的酶，因此是生长的关键限制因素。这种限制在主要的C3作物，如水稻中尤为明显。作为补偿，一些生物体进化出了二氧化碳浓缩机制（CCMs），提高了Rubisco的效率。在藻类中，Rubisco被浓缩在一种称为类pyrenoid的液体状相分离的微室中，与提高光合效率的CCM有关。在C3作物中引入藻类CCM可以改善Rubisco的性能，显著提高产量和粮食生产效率。最近的三项进展为设计Rubisco和在作物中构建藻类CCM开辟了令人兴奋的新途径：1)通过修饰Rubisco的小亚基（SSU）和引入藻类成分，现在可以在植物中产生类芘凝聚物1,2)CRISPR/Cas方法能够取代作物植物中的SSU家族（例如在水稻中2），3)植物Rubisco可以在体外组装（例如在大肠杆菌中3）。该项目旨在组装大米中的类pyrenoid，并表征液体状冷凝物中Rubisco的性能和调节。

Ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) is the driving force behind CO2 assimilation in plants. Despite its importance, Rubisco is a slow and error-prone enzyme, and thus a key limiting factor for growth. This limitation is particularly evident in staple C3 crops, such as rice. To compensate, some organisms have evolved CO2-concentrating mechanisms (CCMs) that increases the efficiency of Rubisco. In algae, Rubisco is condensed within a liquid-like, phase separated microcompartment called the pyrenoid, in association with a CCM that enhance photosynthetic efficiencies. Introducing an algal CCM into a C3 crop could improve the performance of Rubisco and significantly increase yields and the efficiency of food production. Three recent developments have opened up exciting new avenues to engineer Rubisco and build an algal CCM into a crop plant: i) pyrenoid-like condensates can now be generated in plants by modification of the small subunit of Rubisco (SSU) and introduction of algal components1, ii) CRISPR/Cas approaches are able to replace the SSU family in crop plants (e.g. in rice2), iii) plant Rubiscos can be assembled in vitro (i.e. in E. coli3). This project will aim to assemble a pyrenoid in rice and characterise the performance and regulation of Rubisco within the liquid-like condensate.