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Doll NM, Nowack MK. Endosperm cell death: roles and regulation in angiosperms. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:4346-4359. [PMID: 38364847 PMCID: PMC7616292 DOI: 10.1093/jxb/erae052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Accepted: 02/08/2024] [Indexed: 02/18/2024]
Abstract
Double fertilization in angiosperms results in the formation of a second zygote, the fertilized endosperm. Unlike its embryo sibling, the endosperm is a transient structure that eventually undergoes developmentally controlled programmed cell death (PCD) at specific time points of seed development or germination. The nature of endosperm PCD exhibits a considerable diversity, both across different angiosperm taxa and within distinct endosperm tissues. In endosperm-less species, PCD might cause central cell degeneration as a mechanism preventing the formation of a fertilized endosperm. In most other angiosperms, embryo growth necessitates the elimination of surrounding endosperm cells. Nevertheless, complete elimination of the endosperm is rare and, in most cases, specific endosperm tissues persist. In mature seeds, these persisting cells may be dead, such as the starchy endosperm in cereals, or remain alive to die only during germination, like the cereal aleurone or the endosperm of castor beans. In this review, we explore current knowledge surrounding the cellular, molecular, and genetic aspects of endosperm PCD, and the influence environmental stresses have on PCD processes. Overall, this review provides an exhaustive overview of endosperm PCD processes in angiosperms, shedding light on its diverse mechanisms and its significance in seed development and seedling establishment.
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Affiliation(s)
- Nicolas M. Doll
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent 9052, Belgium
- VIB Center of Plant Systems Biology, Ghent 9052, Belgium
| | - Moritz K. Nowack
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent 9052, Belgium
- VIB Center of Plant Systems Biology, Ghent 9052, Belgium
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Yang H, Cai X, Lu D. Effects of Waterlogging at Flowering Stage on the Grain Yield and Starch Quality of Waxy Maize. PLANTS (BASEL, SWITZERLAND) 2023; 13:108. [PMID: 38202416 PMCID: PMC10780669 DOI: 10.3390/plants13010108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 12/24/2023] [Accepted: 12/27/2023] [Indexed: 01/12/2024]
Abstract
Waterlogging is a common abiotic stress in global maize production. Maize flowering stage (from tasseling to silking) is more fragile to environmental stresses, and this stage frequently overlapped the plum rain season in the middle and lower reaches of Yangtze river in China and affect the yield and quality of spring-sown maize severely. In the present study, the soil moisture content under control and waterlogging conditions at the flowering stage was controlled by a negative-pressure water supply and controlling pot device in a pot trial in 2014-2015. The grain yield, starch content, and starch structural and functional properties under two soil moisture levels were compared using Suyunuo5 (SYN5) and Yunuo7 (YN7) as materials, which are the control hybrids of National waxy maize hybrid regional trials in Southern China. The results observed that the grain yield was reduced by 29.1% for SYN5 with waterlogging due to the decreased grain weight and numbers, which was significantly higher than that of YN7 (14.7%), indicated that YN7 was more tolerant to waterlogging. The grain starch content in YN7 was decreased by 9.4% when plants suffered waterlogging at the flowering stage, whereas the content in SYN5 was only decreased in 2014 and unaffected in 2015. The size of starch granules and proportion of small-molecule amylopectin with waterlogging at the flowering stage increased in SYN5 and decreased in YN7 in both years. The type of starch crystalline structure was not changed by waterlogging, whereas the relative crystallinity was reduced in SYN5 and increased in YN7. The pasting viscosities were decreased, and the pasting temperature was unaffected by waterlogging in general. The gelatinization enthalpy was unaffected by waterlogging in both hybrids in both years, whereas the retrogradation enthalpy and percentage in both hybrids were reduced by waterlogging in 2014 and unaffected in 2015. Between the two hybrids, YN7 has high pasting viscosities and low retrogradation percentage than SYN5, indicated its advantages on produce starch for more viscous and less retrograde food. In conclusion, waterlogging at the flowering stage reduced the grain yield, restricted starch accumulation, and deteriorated the pasting viscosity of waxy maize. Results provide information for utilization of waxy maize grain in food production.
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Affiliation(s)
| | | | - Dalei Lu
- Jiangsu Key Laboratory of Crop Genetics and Physiology, Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou 225009, China
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Feng F, Wang Q, Jiang K, Lei D, Huang S, Wu H, Yue G, Wang B. Transcriptome analysis reveals ZmERF055 contributes to waterlogging tolerance in sweetcorn. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2023; 204:108087. [PMID: 37847974 DOI: 10.1016/j.plaphy.2023.108087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 09/24/2023] [Accepted: 10/09/2023] [Indexed: 10/19/2023]
Abstract
Waterlogging is a major disaster damaging crop production. However, most sweetcorn cultivars are not tolerant to waterlogging, which severely threatens their production. In order to understand the genetic mechanisms underlying waterlogging tolerance in sweetcorn, this study conducted a comprehensive investigation of sweetcorn waterlogging tolerance at the levels of physiology, biochemistry, and transcriptome in two sweetcorn CSSLs (chromosome segment substitution lines), D120 and D81. We found that D120 showed increased plant height, root length, root area, adventitious root numbers, antioxidant enzyme activities, and aerenchyma area ratio compared to D81. The transcriptome results showed that 2492 and 2351 differentially expressed genes (DEGs) were obtained at 4 h and 8 h of waterlogging treatment, respectively. Genes involved in reactive oxygen species (ROS) homeostasis, photosynthesis, and alcohol fermentation are sensitive in the waterlogging tolerant genotype D120, resulting in enhanced ROS scavenging ability, adventitious roots, and aerenchyma formation. Additionally, ethylene-, auxin-, and ABA-related genes exhibited different responses to waterlogging stress in sweetcorn. We integrated transcriptome and differential chromosomal fragments data and identified that ZmERF055 on chromosome 9 was directly involved in waterlogging stress. ZmERF055-overexpressing plants consistently exhibited significantly increased waterlogging tolerance and ROS homeostasis in Arabidopsis. These results offer a network of plant hormone signaling, ROS homeostasis, and energy metabolism co-modulating waterlogging tolerance in sweetcorn. Additionally, the findings support ZmERF055 as a potential ideal target gene in crop breeding to improve plant waterlogging tolerance.
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Affiliation(s)
- Faqiang Feng
- Guangdong Key Laboratory of Plant Molecular Breeding, College of Agriculture, South China Agricultural University, Guangzhou, 510642, China
| | - Qing Wang
- Guangdong Key Laboratory of Plant Molecular Breeding, College of Agriculture, South China Agricultural University, Guangzhou, 510642, China
| | - Kerui Jiang
- Guangdong Key Laboratory of Plant Molecular Breeding, College of Agriculture, South China Agricultural University, Guangzhou, 510642, China
| | - Dan Lei
- Guangdong Key Laboratory of Plant Molecular Breeding, College of Agriculture, South China Agricultural University, Guangzhou, 510642, China
| | - Shilin Huang
- Guangdong Key Laboratory of Plant Molecular Breeding, College of Agriculture, South China Agricultural University, Guangzhou, 510642, China
| | - Huichao Wu
- Guangdong Key Laboratory of Plant Molecular Breeding, College of Agriculture, South China Agricultural University, Guangzhou, 510642, China
| | - Gaohong Yue
- Southern Zhejiang Key Laboratory of Crop Breeding, Wenzhou Vocational College of Science and Technology, Wenzhou, Zhejiang, 325006, China.
| | - Bo Wang
- Guangdong Key Laboratory of Plant Molecular Breeding, College of Agriculture, South China Agricultural University, Guangzhou, 510642, China.
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Zhao C, Xu W, Li H, Dai W, Zhang Z, Qiang S, Song X. The Rapid Cytological Process of Grain Determines Early Maturity in Weedy Rice. FRONTIERS IN PLANT SCIENCE 2021; 12:711321. [PMID: 34531884 PMCID: PMC8438156 DOI: 10.3389/fpls.2021.711321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 08/09/2021] [Indexed: 06/13/2023]
Abstract
Shorter grain-filling period and rapid endosperm development endow weedy rice (WR) with early maturity compared to cultivated rice (CR). However, the role of the cytological features and antioxidative enzyme system during grain development are largely unexplored. We selected four biotypes of WR and their associated cultivated rice (ACR) types from different latitudes to conduct a common garden experiment. The difference in the cytological features of endosperm between WR and ACR was compared by chemical staining, and the cell viability and nuclear morphometry of endosperm cells were observed by optical microscopy. Furthermore, antioxidative enzyme activity was measured during grain filling. Anatomic observation of endosperm shows that the development process of endosperm cell in WR was more rapid and earlier than that in ACR. The percentage of degraded nuclei of WR was 2-83% more than that of ACR. Endosperm cells in WR lost viability 2-6 days earlier than those in ACR. The antioxidant enzyme activity of WR was lower than that of ACR during grain filling. The ability of WR to scavenge reactive oxygen species (ROS) was weaker than that of ACR, which may contribute to the rapid cytological process in the endosperm cells of WR. The rapid cytological process and weaker ability to scavenge ROS in endosperm cells may contribute to early maturity in WR.
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Matilla AJ. Cellular oxidative stress in programmed cell death: focusing on chloroplastic 1O 2 and mitochondrial cytochrome-c release. JOURNAL OF PLANT RESEARCH 2021; 134:179-194. [PMID: 33569718 DOI: 10.1007/s10265-021-01259-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 01/28/2021] [Indexed: 06/12/2023]
Abstract
The programmed cell death (PCD) occurs when the targeted cells have fulfilled their task or under conditions as oxidative stress generated by ROS species. Thus, plants have to deal with the singlet oxygen 1O2 produced in chloroplasts. 1O2 is unlikely to act as a primary retrograde signal owing to its high reactivity and short half-life. In addition to its high toxicity, the 1O2 generated under an excess or low excitation energy might also act as a highly versatile signal triggering chloroplast-to-nucleus retrograde signaling (ChNRS) and nuclear reprogramming or cell death. Molecular and biochemical studies with the flu mutant, which accumulates protochlorophyllide in the dark, demonstrated that chloroplastic 1O2-driven EXECUTER-1 (EX1) and EX2 proteins are involved in the 1O2-dependent response. Both EX1 and EX2 are necessary for full suppression of 1O2-induced gene expression. That is, EXECUTER proteolysis via the ATP-dependent zinc protease (FtsH) is an integral part of 1O2-triggered retrograde signaling. The existence of at least two independent ChNRS involving EX1 and β-cyclocitral, and dihydroactinidiolide and OXI1, respectively, seem clear. Besides, this update also focuses on plant PCD and its relation with mitochondrial cytochrome-c (Cytc) release to cytosol. Changes in the dynamics and morphology of mitochondria were shown during the onset of cell death. The mitochondrial damage and translocation of Cytc may be one of the major causes of PCD triggering. Together, this current overview illustrates the complexity of the cellular response to oxidative stress development. A puzzle with the majority of its pieces still not placed.
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Affiliation(s)
- Angel J Matilla
- Departamento de Biología Funcional, Facultad de Farmacia, Universidad de Santiago de Compostela (USC), Campus Vida, 15782, Santiago de Compostela, A Coruña, Spain.
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Effects of waterlogging at grain formation stage on starch structure and functionality of waxy maize. Food Chem 2019; 294:187-193. [DOI: 10.1016/j.foodchem.2019.05.072] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 03/09/2019] [Accepted: 05/07/2019] [Indexed: 11/20/2022]
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Qi YH, Mao FF, Zhou ZQ, Liu DC, Deng XY, Li JW, Mei FZ. The release of cytochrome c and the regulation of the programmed cell death progress in the endosperm of winter wheat (Triticum aestivum L.) under waterlogging. PROTOPLASMA 2018; 255:1651-1665. [PMID: 29717349 DOI: 10.1007/s00709-018-1256-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Accepted: 04/16/2018] [Indexed: 06/08/2023]
Abstract
It has been shown in mammalian systems that the mitochondria can play a key role in the regulation of apoptosis by releasing intermembrane proteins (such as cytochrome c) into the cytosol. Cytochrome c released from the mitochondria to the cytoplasm activates proteolytic enzyme cascades, leading to specific nuclear DNA degradation and cell death. This pathway is considered to be one of the important regulatory mechanisms of apoptosis. Previous studies have shown that endosperm cell development in wheat undergoes specialized programmed cell death (PCD) and that waterlogging stress accelerates the PCD process; however, little is known regarding the associated molecular mechanism. In this study, changes in mitochondrial structure, the release of cytochrome c, and gene expression were studied in the endosperm cells of the wheat (Triticum aestivum L.) cultivar "huamai 8" during PCD under different waterlogging durations. The results showed that waterlogging aggravated the degradation of mitochondrial structure, increased the mitochondrial permeability transition (MPT), and decreased mitochondrial transmembrane potential (ΔΨm), resulting in the advancement of the endosperm PCD process. In situ localization and western blotting of cytochrome c indicated that with the development of the endosperm cell, cytochrome c was gradually released from the mitochondria to the cytoplasm, and waterlogging stress led to an advancement and increase in the release of cytochrome c. In addition, waterlogging stress resulted in the increased expression of the voltage-dependent anion channel (VDAC) and adenine nucleotide translocator (ANT), suggesting that the mitochondrial permeability transition pore (MPTP) may be involved in endosperm PCD under waterlogging stress. The MPTP inhibitor cyclosporine A effectively suppressed cell death and cytochrome c release during wheat endosperm PCD. Our results indicate that the mitochondria play important roles in the PCD of endosperm cells and that the increase in mitochondrial damage and corresponding release of cytochrome c may be one of the major causes of endosperm PCD advancement under waterlogging.
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Affiliation(s)
- Yuan-Hong Qi
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, Hubei, China
| | - Fang-Fang Mao
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, Hubei, China
| | - Zhu-Qing Zhou
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, Hubei, China.
| | - Dong-Cheng Liu
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, Hubei, China
| | - Xiang-Yi Deng
- College of Food and Biological Science and Technology, Wuhan Institute of Design and Sciences, Wuhan, 430070, Hubei, China
| | - Ji-Wei Li
- College of Food and Biological Science and Technology, Wuhan Institute of Design and Sciences, Wuhan, 430070, Hubei, China
| | - Fang-Zhu Mei
- Division of Science and Technology, Huazhong Agricultural University, Wuhan, 430070, Hubei, China
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Li C, Li C, Wang B, Zhang R, Fu K, Gale WJ, Li C. Programmed cell death in wheat (Triticum aestivum L.) endosperm cells is affected by drought stress. PROTOPLASMA 2018; 255:1039-1052. [PMID: 29380071 DOI: 10.1007/s00709-018-1203-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2017] [Accepted: 01/08/2018] [Indexed: 05/28/2023]
Abstract
Drought frequently occurs during wheat (Triticum aestivum L.) grain filling. The objectives of this study were (i) to investigate the effect of post-anthesis drought on programmed cell death (PCD) in wheat endosperm cells and (ii) to examine the role of ethylene (ETH) receptors and abscisic acid (ABA) in regulating wheat endosperm PCD. Two winter wheat cultivars ('Xindong 18' and 'Xindong 22') were used in this study. Grain samples were collected from normal and drought stressed plants at 5-day intervals between 5 and 35 days post-anthesis. The samples were then compared with respect to cell viability, nuclear morphometry, cell ultrastructure, DNA integrity, nucleic acid content, and nuclease activity. Analysis was also conducted about gene transcripts related to PCD, ETH receptors, and ABA biosynthesis and degradation. Drought stress reduced cell viability, accelerated nuclear deformation, and increased mitochondrial dissolution. The activity of nucleic acid hydrolase was greater, and the nucleic acid concentrations were less in the drought treatments than in the control. As a result, the peak in DNA fragmentation occurred earlier in the drought treatment. Drought stress significantly increased the expression of four genes related to ABA (nced1, nced2, ao1, ao2). In contrast, drought significantly reduced the expression of four genes related to ETH receptors (ers1, ers2 etr1, etr2) and one gene related to PCD (dad1). In summary, the results indicated that drought stress caused PCD to occur earlier in the endosperm of winter wheat.
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Affiliation(s)
- Chao Li
- College of Agriculture/The Key Laboratory of Oasis Eco-agriculture, Xinjiang Production and Construction Group, Shihezi University, Shihezi, Xinjiang, 832000, People's Republic of China
| | - Cheng Li
- College of Agriculture/The Key Laboratory of Oasis Eco-agriculture, Xinjiang Production and Construction Group, Shihezi University, Shihezi, Xinjiang, 832000, People's Republic of China
| | - Bingbing Wang
- College of Agriculture/The Key Laboratory of Oasis Eco-agriculture, Xinjiang Production and Construction Group, Shihezi University, Shihezi, Xinjiang, 832000, People's Republic of China
| | - Runqi Zhang
- College of Agriculture/The Key Laboratory of Oasis Eco-agriculture, Xinjiang Production and Construction Group, Shihezi University, Shihezi, Xinjiang, 832000, People's Republic of China
| | - Kaiyong Fu
- College of Agriculture/The Key Laboratory of Oasis Eco-agriculture, Xinjiang Production and Construction Group, Shihezi University, Shihezi, Xinjiang, 832000, People's Republic of China
| | - William J Gale
- College of Agriculture/The Key Laboratory of Oasis Eco-agriculture, Xinjiang Production and Construction Group, Shihezi University, Shihezi, Xinjiang, 832000, People's Republic of China
| | - Chunyan Li
- College of Agriculture/The Key Laboratory of Oasis Eco-agriculture, Xinjiang Production and Construction Group, Shihezi University, Shihezi, Xinjiang, 832000, People's Republic of China.
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Cheng XX, Yu M, Zhang N, Zhou ZQ, Xu QT, Mei FZ, Qu LH. Reactive oxygen species regulate programmed cell death progress of endosperm in winter wheat (Triticum aestivum L.) under waterlogging. PROTOPLASMA 2016; 253:311-27. [PMID: 25854793 DOI: 10.1007/s00709-015-0811-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2014] [Accepted: 03/20/2015] [Indexed: 05/18/2023]
Abstract
Previous studies have proved that waterlogging stress accelerates the programmed cell death (PCD) progress of wheat endosperm cells. A highly waterlogging-tolerant wheat cultivar Hua 8 and a waterlogging susceptible wheat cultivar Hua 9 were treated with different waterlogging durations, and then, dynamic changes of reactive oxygen species (ROS), gene expressions, and activities of antioxidant enzymes in endosperm cells were detected. The accumulation of ROS increased considerably after 7 days of waterlogging treatment (7 DWT) and 12 DWT in both cultivars compared with control group (under non-waterlogged conditions), culminated at 12 DAF (days after flowering) and reduced hereafter. Waterlogging resulted in a great increase of H2O2 and O2 (-) in plasma membranes, cell walls, mitochondrias, and intercellular spaces with ultracytochemical localization. Moreover, the deformation and rupture of cytomembranes as well as the swelling and distortion of mitochondria were obvious. Under waterlogging treatment conditions, catalase (CAT) gene expression increased in endosperm of Hua 8 but activity decreased. In addition, Mn superoxide dismutase (MnSOD) gene expression and superoxide dismutase (SOD) activity increased. Compared with Hua 8, both CAT, MnSOD gene expressions and CAT, SOD activities decreased in Hua 9. Moreover, ascorbic acid and mannitol relieve the intensifying of PCD processes in Hua 8 endosperm cells induced by waterlogging. These results indicate that ROS have important roles in the PCD of endosperm cells, the changes both CAT, MnSOD gene expressions and CAT, SOD activities directly affected the accumulation of ROS in two different wheat cultivars under waterlogging, ultimately led to the PCD acceleration of endosperm.
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Affiliation(s)
- Xiang-Xu Cheng
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Min Yu
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Nan Zhang
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Zhu-Qing Zhou
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China.
| | - Qiu-Tao Xu
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Fang-Zhu Mei
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Liang-Huan Qu
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
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Chen Y, Chen X, Wang H, Bao Y, Zhang W. Examination of the leaf proteome during flooding stress and the induction of programmed cell death in maize. Proteome Sci 2014; 12:33. [PMID: 25028572 PMCID: PMC4099015 DOI: 10.1186/1477-5956-12-33] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Accepted: 05/30/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Maize is a major economic crop worldwide, with substantial crop loss attributed to flooding. During a stress response, programmed cell death (PCD) can be an effective way for plants better adapt. To identify flooding stress related PCD proteins in maize leaves, proteomic analysis was performed using two-dimensional fluorescence difference gel electrophoresis (2D-DIGE) and mass spectrometry. RESULTS Comparative proteomics was combined with physiological and biochemical analysis of maize leaves under flooding stress. Fv/Fm, qP, qN and relative water content (RWC) were found to be altered in response to flooding stress, with an increase in H2O2 content noted in vivo. Furthermore, DNA ladder detection indicated that PCD had occurred under flooding treatment. The maize leaf proteome was analyzed via 2D-DIGE gel, with a total of 32 differentially expressed spots isolated, 31 spots were successfully identified via MALDI-TOF/TOF MS which represent 28 proteins. The identified proteins were related to energy metabolism and photosynthesis, PCD, phytohormones and polyamines. To better characterize the role of translationally controlled tumor protein (TCTP) in PCD during a stress response, mRNA expression was examined in different plants by stress-induced PCD. These included heat stress induced rice protoplasts, Tobacco Mosaic Virus infected tobacco leaves and dark induced rice and Arabidopsis thaliana leaves, all of which showed active PCD, and TCTP expression was increased in different degrees. Moreover, S-adenosylmethionine synthase 2 (SAMS2) and S-adenosylmethionine decarboxylase (SAMDC) mRNA expression were also increased, but ACC synthase (ACS) and ACC oxidase (ACO) mRNA expression were not found in maize leaves following flooding. Lastly, ethylene and polyamine concentrations were increased in response to flooding treatment in maize leaves. CONCLUSIONS Following flooding stress, the photosynthetic systems were damaged, resulting in a disruption in energy metabolism, with the noted photosynthetic decline also possibly attributed to ROS production. The observed PCD could be regulated by TCTP with a possible role for H2O2 in TCTP induction under flooding stress. Additionally, increased SAMS2 expression was closely associated with an increased polyamine synthesis during flooding treatment.
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Affiliation(s)
- Yu Chen
- Department of Biochemistry and Molecular Biology, College of Life Science, Nanjing Agricultural University, Nanjing, Jiangsu, PR, China
| | - Xi Chen
- Department of Biochemistry and Molecular Biology, College of Life Science, Nanjing Agricultural University, Nanjing, Jiangsu, PR, China
| | - Hongjuan Wang
- Department of Biochemistry and Molecular Biology, College of Life Science, Nanjing Agricultural University, Nanjing, Jiangsu, PR, China
| | - Yiqun Bao
- Department of Biochemistry and Molecular Biology, College of Life Science, Nanjing Agricultural University, Nanjing, Jiangsu, PR, China
| | - Wei Zhang
- Department of Biochemistry and Molecular Biology, College of Life Science, Nanjing Agricultural University, Nanjing, Jiangsu, PR, China
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