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Zhang Q, Qi X, Xu W, Li Y, Zhang Y, Peng C, Fang Y. Response of transgenic Arabidopsis expressing maize C 4 photosynthetic enzyme genes to high light. Plant Signal Behav 2021; 16:1885894. [PMID: 33566717 PMCID: PMC7971240 DOI: 10.1080/15592324.2021.1885894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 01/30/2021] [Accepted: 02/01/2021] [Indexed: 06/12/2023]
Abstract
This study assessed the responses of wild-type (WT) and transgenic Arabidopsis expressing seven combinations of maize (Zea mays) genes phosphoenolpyruvate carboxylase (pepc), pyruvate phosphate dikinase (ppdk), and NADP-malic enzyme (nadp-me) to high light. Our results showed that the net CO2 assimilation rate (Pn) and shoot dry weight of four of the transgenic Arabidopsis genotypes were significantly different from those of WT under high-light treatment, being in the order of Zmpepc+Zmppdk+Zmnadp-me (PC-K-M) > Zmpepc+Zmppdk (PC-K) > Zmpepc (PC), Zmpepc+Zmnadp-me (PC-M) > WT. The other genotypes did not differ from WT. This indicated that Zmpepc was essential for maintaining high photosynthetic performance under high light, Zmppdk had a positive synergistic effect on Zmpepc, and the combination of all three genes had the greatest synergistic effect. These four genotypes also maintained higher photosystem II (PSII) activity (K-phase, J-phase, RC/CSm), electron transfer capacity (J-phase), and photochemical efficiency (TRo/ABS), and accumulated less reactive oxygen species (O2·-, H2O2) and suffered less damage to the membrane system (MDA) than WT under high light. Collectively, PC, PC-K, PC-M, and PC-K-M used most of the absorbed energy for CO2 assimilation through a significantly higher Pn, which reduced the generation of excess electrons in the photosynthetic apparatus, thereby reducing damage to the membrane system and PSII. This ultimately resulted in improved high-light tolerance. Pn was the main reason for the significant difference in the high-light tolerance of the four genotypes. Joint expression of the three maize genes may be of great value in the genetic improvement of high-light tolerance in C3 crops.
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Affiliation(s)
- Qingchen Zhang
- National Engineering Laboratory of Wheat, Key Laboratory of Wheat Biology and Genetic Breeding in Central Huanghuai Area, Ministry of Agriculture, Institute of Crop Molecular Breeding, Henan Academy of Agricultural Sciences, Zhengzhou, China
- College of Biology and Food, Shangqiu Normal University, Shangqiu, China
| | - Xueli Qi
- National Engineering Laboratory of Wheat, Key Laboratory of Wheat Biology and Genetic Breeding in Central Huanghuai Area, Ministry of Agriculture, Institute of Crop Molecular Breeding, Henan Academy of Agricultural Sciences, Zhengzhou, China
| | - Weigang Xu
- National Engineering Laboratory of Wheat, Key Laboratory of Wheat Biology and Genetic Breeding in Central Huanghuai Area, Ministry of Agriculture, Institute of Crop Molecular Breeding, Henan Academy of Agricultural Sciences, Zhengzhou, China
| | - Yan Li
- National Engineering Laboratory of Wheat, Key Laboratory of Wheat Biology and Genetic Breeding in Central Huanghuai Area, Ministry of Agriculture, Institute of Crop Molecular Breeding, Henan Academy of Agricultural Sciences, Zhengzhou, China
| | - Yu Zhang
- National Engineering Laboratory of Wheat, Key Laboratory of Wheat Biology and Genetic Breeding in Central Huanghuai Area, Ministry of Agriculture, Institute of Crop Molecular Breeding, Henan Academy of Agricultural Sciences, Zhengzhou, China
| | - Chaojun Peng
- National Engineering Laboratory of Wheat, Key Laboratory of Wheat Biology and Genetic Breeding in Central Huanghuai Area, Ministry of Agriculture, Institute of Crop Molecular Breeding, Henan Academy of Agricultural Sciences, Zhengzhou, China
| | - Yuhui Fang
- National Engineering Laboratory of Wheat, Key Laboratory of Wheat Biology and Genetic Breeding in Central Huanghuai Area, Ministry of Agriculture, Institute of Crop Molecular Breeding, Henan Academy of Agricultural Sciences, Zhengzhou, China
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Chastain CJ, Baird LM, Walker MT, Bergman CC, Novbatova GT, Mamani-Quispe CS, Burnell JN. Maize leaf PPDK regulatory protein isoform-2 is specific to bundle sheath chloroplasts and paradoxically lacks a Pi-dependent PPDK activation activity. J Exp Bot 2018; 69:1171-1181. [PMID: 29281064 PMCID: PMC6019023 DOI: 10.1093/jxb/erx471] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 12/04/2017] [Indexed: 05/18/2023]
Abstract
In C4 plants, the pyruvate phosphate dikinase regulatory protein (PDRP) regulates the C4 pathway enzyme pyruvate phosphate dikinase (PPDK) in response to changes in incident light intensity. In maize (Zea mays) leaves, two distinct isoforms of PDRP are expressed, ZmPDRP1 and ZmPDRP2. The properties and C4 function of the ZmPDRP1 isoform are well understood. However, the PDRP2 isoform has only recently been identified and its properties and function(s) in maize leaves are unknown. We therefore initiated an investigation into the maize PDRP2 isoform by performing a side by side comparison of its enzyme properties and cell-specific distribution with PDRP1. In terms of enzyme functionality, PDRP2 was found to possess the same protein kinase-specific activity as PDRP1. However, the PDRP2 isoform was found to lack the phosphotransferase activity of the bifunctional PDRP1 isoform except when PDRP2 in the assays is elevated 5- to 10-fold. A primarily immuno-based approach was used to show that PDRP1 is strictly expressed in mesophyll cells and PDRP2 is strictly expressed in bundle sheath strand cells (BSCs). Additionally, using in situ immunolocalization, we establish a regulatory target for PDRP2 by showing a significant presence of C4 PPDK in BSC chloroplasts. However, a metabolic role for PPDK in this compartment is obscure, assuming PPDK accumulating in this compartment would be irreversibly inactivated each dark cycle by a monofunctional PDRP2.
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Affiliation(s)
- Chris J Chastain
- Department of Biosciences, Minnesota State University-Moorhead, USA
- Correspondence:
| | - Lisa M Baird
- Department of Biology, University of San Diego, San Diego, CA, USA
| | | | | | | | | | - Jim N Burnell
- Department of Molecular and Cell Biology, James Cook University, Australia
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