Engineering of Improving Thermotolerance of Rubisco Activase

Improving the photosynthetic efficiency of plants contributes to increased crop yields. Lifeasible has successfully developed a variety of reliable and economical solutions for engineering chloroplast photosynthesis. Here, our engineers focused on using chloroplast genetic engineering to improve photosynthesis at high temperatures by Rubisco activase to increase crop yield.

Introduction

Rubisco activase (RCA) maintains Rubisco activity by removing inhibitors from the Rubisco catalytic site in an ATP-dependent manner. Studies have shown that in many plant species the activation state of Rubisco is reduced at high temperature because the activity of Rubisco activase is not sufficient to keep up with the faster rate of Rubisco inactivation at high temperature due to its thermotolerance. In addition, heat stress may be a key factor negatively affecting plant biomass and crop yield, given the increased global temperature. Therefore, the thermal sensitivity of RCA under heat stress is one of the key factors hindering photosynthesis and plant productivity. It would be interesting to investigate methods capable of maintaining RCA activity without denaturing itself and forming insoluble aggregates beyond species-specific temperatures.

Fig. 1. A model on the mechanism of activation of Rubisco by Rubisco activase. (Wijewardene I, et al., 2017)

Solutions

Sustaining photosynthetic activity at high temperature by enhancing the thermal stability of RCA becomes an attractive and practical strategy. Based on the chloroplast transformation technology platform, Lifeasible can provide specialized solutions to improve the thermostability of Rubisco activase at high temperature. Our goal was to overexpress different RCAs in multiple plant species to determine their ability to enhance thermotolerance, thereby increasing photosynthetic rate and plant productivity at high temperatures.

Our engineers are committed to developing molecular methods that can be used to improve thermal tolerance by identifying and characterizing subunits and isoforms of RCA. We have successfully detected heat-induced RCA isoforms as well as constitutively expressed isoforms in many crops including wheat, cotton and maize. In addition, we employed various strategies to keep the RCA fully functional at high temperature.

• Identifing or manipulate 3'-UTR length of RCA isoforms.
• ldentifing heat-inducible RCA isoforms.
• RCA gene shuffling.
• Synthesis of chimeric RCA.
• Overexpression of a naturally thermomostable RCA.
• Overexpression of thermostable RCA isoform.
• Editing the thermolabile RCA isoforms.
• ldentifing thermotolerant cultivars in a crop species.

Attractive Advantages of Our Solutions

• Multiple biological tool support, including whole genomes of genetically engineered plant species, multiple databases, bioinformatics tools, next-generation sequencing, and more.
• We can help you design more thermostable RCAs with better Rubisco activation properties, as well as molecular markers important for determining thermostable traits in plants.
• Achieving retention of RCA activity at high temperature and interaction with Rubisco at the molecular level.
• Helping to accelerate the process of identifying and predicting novel and putative heat-responsive genes in plant germplasm.

Lifeasible's goal is to provide customers around the world with fully customized chloroplast engineered solutions for improving the thermostability of Rubisco Activase at high temperature. Our various strategies will fully meet your needs. Please contact us to discuss further details to ensure your next success.

References

1. Wijewardene I, Shen G, Zhang H. (2021) Enhancing crop yield by using Rubisco activase to improve photosynthesis under elevated temperatures[J]. Stress Biology. 1(1): 1-20.
2. Crafts-Brandner S J, Salvucci M E. (2000) Rubisco activase constrains the photosynthetic potential of leaves at high temperature and CO₂[J]. Proceedings of the National Academy of Sciences. 97(24): 13430-13435.