Engineering a New Chloroplastic Photorespiratory Bypass to In crease Photosynthetic Efficiency and Productivity in Rice  

作　　者：Bo-Ran Shen Li-Min Wang Xiu-Ling Lin Zhen Yao Hua-Wei Xu Cheng-Hua Zhu Hai-Yan Teng Li-Li Cui E.-E. Liu Jian-Jun Zhang Zheng-Hui He Xin-Xiang Peng 

机构地区：[1]State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China [2]College of Agricultural, Henan University of Science and Technology, Luoyang, Henan, China [3]Departme nt of Biology, San Fran cisco State University, San Fran cisco, CA, USA [4]These authors contributed equally to this article.

出　　处：《Molecular Plant》2019年第2期199-214,共16页分子植物（英文版）

基　　金：the National Natural Science Foundation of China (31470343, 31770256);the Science and Technology Project of Guangzhou City (201607020006).

摘　　要：Over the past few years, three photorespiratory bypasses have been introduced into plants, two of which led to observable in creases in photos yn thesis and biomass yield. However, most of the experiments were carried out using Arabidopsis under controlled environmental conditions, and the increases were only observed under low-light and short-day conditions. In this study, we designed a new photorespiratory bypass (called GOC bypass), characterized by no reducing equivalents being produced during a complete oxidation of glycolate into CO2 catalyzed by three rice-self-originating enzymes, i.e., glycolate oxidase, oxalate oxidase, and catalase. We successfully established this bypass in rice chloroplasts using a multi-gene assembly and transformation system. Transgenic rice plants carrying GOC bypass (GOC plants) showed significant increases in photosynthesis efficiency, biomass yield, and nitrogen content, as well as several other CO2-enriched phe no types under both greenhouse and field conditions .Grain yield of GOC plants varied depending on seeding season and was increased significantly in the spring. We further demonstrated that GOC plants had significant advantages under high-light conditions and that the improvements in GOC plants resulted primarily from a photosynthetic CO2-concentrating effect rather than from improved energy balance. Taken together, our results reveal that engineering a newly designed chloroplastic photorespiratory bypass could increase photosynthetic efficiency and yield of rice plants grown in field conditions, particularly under high light.

关 键 词：photorespiratory BYPASS PHOTOSYNTHETIC EFFICIENCY PRODUCTIVITY RICE 

分 类 号：Q[生物学]