CO2 recycling by phosphoenolpyruvate carboxylase enables cassava leaf metabolism to tolerate low water availability

Frontiers in Plant Science

Plant Science

Nattharat Punyasu¹  Treenut Saithong²  Saowalak Kalapanulak² 

[1] Bioinformatics and Systems Biology Program, School of Bioresources and Technology, and School of Information Technology, King Mongkut’s University of Technology Thonburi (Bang Khun Thian), Bangkok, Thailand;Bioinformatics and Systems Biology Program, School of Bioresources and Technology, and School of Information Technology, King Mongkut’s University of Technology Thonburi (Bang Khun Thian), Bangkok, Thailand;School of Bioresources and Technology, King Mongkut’s University of Technology Thonburi (Bang Khun Thian), Bangkok, Thailand;Systems Biology and Bioinformatics Research Group, Pilot Plant Development and Training Institute, King Mongkut’s University of Technology Thonburi (Bang Khun Thian), Bangkok, Thailand;

关键词: carbon metabolism;    genome-scale metabolic modeling;    cassava leaf;    Manhiot esculenta;    drought response;    enol;    CO2 recycling;    PEPC;   

DOI  :  10.3389/fpls.2023.1159247

 received in 2023-02-05, accepted in 2023-04-12,  发布年份 2023

来源: Frontiers

【 摘 要 】

Cassava is a staple crop that acclimatizes well to dry weather and limited water availability. The drought response mechanism of quick stomatal closure observed in cassava has no explicit link to the metabolism connecting its physiological response and yield. Here, a genome-scale metabolic model of cassava photosynthetic leaves (leaf-MeCBM) was constructed to study on the metabolic response to drought and stomatal closure. As demonstrated by leaf-MeCBM, leaf metabolism reinforced the physiological response by increasing the internal CO2 and then maintaining the normal operation of photosynthetic carbon fixation. We found that phosphoenolpyruvate carboxylase (PEPC) played a crucial role in the accumulation of the internal CO2 pool when the CO2 uptake rate was limited during stomatal closure. Based on the model simulation, PEPC mechanistically enhanced drought tolerance in cassava by providing sufficient CO2 for carbon fixation by RuBisCO, resulting in high production of sucrose in cassava leaves. The metabolic reprogramming decreased leaf biomass production, which may lead to maintaining intracellular water balance by reducing the overall leaf area. This study indicates the association of metabolic and physiological responses to enhance tolerance, growth, and production of cassava in drought conditions.

【 授权许可】

Unknown   
Copyright © 2023 Punyasu, Kalapanulak and Saithong