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Shi T, Fan D, Xu C, Zheng G, Zhong C, Feng F, Chow WS. The Fitting of the OJ Phase of Chlorophyll Fluorescence Induction Based on an Analytical Solution and Its Application in Urban Heat Island Research. PLANTS (BASEL, SWITZERLAND) 2024; 13:452. [PMID: 38337985 PMCID: PMC10857409 DOI: 10.3390/plants13030452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 01/28/2024] [Accepted: 02/01/2024] [Indexed: 02/12/2024]
Abstract
Chlorophyll (Chl) fluorescence induction (FI) upon a dark-light transition has been widely analyzed to derive information on initial events of energy conversion and electron transfer in photosystem II (PSII). However, currently, there is no analytical solution to the differential equation of QA reduction kinetics, raising a doubt about the fitting of FI by numerical iteration solution. We derived an analytical solution to fit the OJ phase of FI, thereby yielding estimates of three parameters: the functional absorption cross-section of PSII (σPSII), a probability parameter that describes the connectivity among PSII complexes (p), and the rate coefficient for QA- oxidation (kox). We found that σPSII, p, and kox exhibited dynamic changes during the transition from O to J. We postulated that in high excitation light, some other energy dissipation pathways may vastly outcompete against excitation energy transfer from a closed PSII trap to an open PSII, thereby giving the impression that connectivity seemingly does not exist. We also conducted a case study on the urban heat island effect on the heat stability of PSII using our method and showed that higher-temperature-acclimated leaves had a greater σPSII, lower kox, and a tendency of lower p towards more shade-type characteristics.
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Affiliation(s)
- Tongxin Shi
- The Key Laboratory for Silviculture and Conservation of Ministry of Education, College of Forestry, Beijing Forestry University, Beijing 100083, China; (T.S.)
| | - Dayong Fan
- The Key Laboratory for Silviculture and Conservation of Ministry of Education, College of Forestry, Beijing Forestry University, Beijing 100083, China; (T.S.)
| | - Chengyang Xu
- The Key Laboratory for Silviculture and Conservation of Ministry of Education, College of Forestry, Beijing Forestry University, Beijing 100083, China; (T.S.)
| | - Guoming Zheng
- Yi Zong Qi Technology (Beijing) Co., Ltd., Beijing 100095, China
| | - Chuanfei Zhong
- Institute of Forestry and Pomology, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100093, China
| | - Fei Feng
- The Key Laboratory for Silviculture and Conservation of Ministry of Education, College of Forestry, Beijing Forestry University, Beijing 100083, China; (T.S.)
| | - Wah Soon Chow
- Division of Plant Sciences, Research School of Biology, The Australian National University, Acton, ACT 2601, Australia
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2
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Zavafer A, Mancilla C, Jolley G, Murakami K. On the concepts and correct use of radiometric quantities for assessing the light environment and their application to plant research. Biophys Rev 2023; 15:385-400. [PMID: 37396445 PMCID: PMC10310645 DOI: 10.1007/s12551-023-01051-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Accepted: 03/06/2023] [Indexed: 04/07/2023] Open
Abstract
Light is one of the most important factors for photosynthetic organisms to grow. Historically, the amount of light in plant sciences has been referred to as light intensity, irradiance, photosynthetic active radiation, photon flux, photon flux density, etc. On occasion, all these terms are used interchangeably, yet they refer to different physical units and each metric offers distinct information. Even for experts in the fields of plant photobiology, the use of these terms is confusing, and there is a loose implementation of each concept. This makes the use of radiometric units even more confusing to non-experts when looking for ways to measure light, since they could easily feel overwhelmed by the specialized literature. The use of scientific concepts must be accurate, as ambiguity in the use of radiometric quantities can lead to inconsistencies in analysis, thus decreasing the comparability between experiments and to the formulation of incorrect experimental designs. In this review, we provide a simple yet comprehensive view of the use of radiometric quantities in an effort to clarify their meaning and applications. To facilitate understanding, we adopt a minimum amount of mathematical expressions and provide a historical summary of the use of radiometry (with emphasis on plant sciences), examples of uses, and a review of the available instrumentation for radiometric measurements.
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Affiliation(s)
- Alonso Zavafer
- Department of Engineering, Brock University, St. Catharines, ON Canada
| | - Cristian Mancilla
- Department of Engineering, Brock University, St. Catharines, ON Canada
| | - Gregory Jolley
- Research School of Chemistry, The Australian National University, Canberra, ACT 2600 Australia
| | - Keach Murakami
- Hokkaido Agricultural Research Center, National Agriculture and Food Research Organization, Sapporo, Japan
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3
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Lysenko V, Varduny T. High levels of anoxygenic photosynthesis revealed by dual-frequency Fourier photoacoustics in Ailanthus altissima leaves. FUNCTIONAL PLANT BIOLOGY : FPB 2022; 49:573-586. [PMID: 35413232 DOI: 10.1071/fp21093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 03/02/2022] [Indexed: 06/14/2023]
Abstract
In contrast to oxygenic photosynthesis, true anoxygenic photosynthesis is not associated with O2 evolution originated from water photolysis but still converts light energy to that of the phosphoanhydride bonds of ATP. In a narrow sense, anoxygenic photosynthesis is mainly known as to be related to the purple and green sulfur bacteria, but in a broad sense, it also occurs in the vascular plants. The portion of photosynthetic water photolysis that is compensated by the processes of O2 uptake (respiration, photorespiration, Mehler cycle, etc.) may be referred to as 'quasi' anoxygenic photosynthesis. Photoacoustic method allows for the separate detection of photolytic O2 at frequencies of measuring light about 20-40Hz, whereas at 250-400Hz, it detects the photochemical energy storage. We have developed a fast-Fourier transform photoacoustic method enabling measurements of both these signals simultaneously in one sample. This method allows to calculate oxygenic coefficients, which reflect the part of photochemically stored light energy that is used for the water photolysis. We show that the true anoxygenic photosynthesis in Ailanthus altissima Mill. leaves reached very high levels under low light, under moderate light at the beginning of the 1-h period, and at the end of the 40-min period under saturating light.
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Affiliation(s)
- Vladimir Lysenko
- Academy of Biology and Biotechnology, Southern Federal University, Botanichesky spusk 7, 344041 Rostov-on-Don, Russia
| | - Tatyana Varduny
- Academy of Biology and Biotechnology, Southern Federal University, Botanichesky spusk 7, 344041 Rostov-on-Don, Russia
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Chow WS. My precarious career in photosynthesis: a roller-coaster journey into the fascinating world of chloroplast ultrastructure, composition, function and dysfunction. PHOTOSYNTHESIS RESEARCH 2021; 149:5-24. [PMID: 33543372 DOI: 10.1007/s11120-021-00818-2] [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: 10/23/2020] [Accepted: 01/04/2021] [Indexed: 06/12/2023]
Abstract
Despite my humble beginnings in rural China, I had the good fortune of advancing my career and joining an international community of photosynthesis researchers to work on the 'light reactions' that are a fundamental process in Nature. Along with supervisors, mentors, colleagues, students and lab assistants, I worked on ionic redistributions across the photosynthetic membrane in response to illumination, photophosphorylation, forces that regulate the stacking of photosynthetic membranes, the composition of components of the photosynthetic apparatus during acclimation to the light environment, and the failure of the photosynthetic machinery to acclimate to too much light or even to cope with moderate light due to inevitable photodamage. These fascinating underlying mechanisms were investigated in vitro and in vivo. My career path, with its ups and downs, was never secure, but the reward of knowing a little more of the secret of Nature offset the job uncertainty.
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Affiliation(s)
- Wah Soon Chow
- Division of Plant Sciences, Research School of Biology, The Australian National University, 46 Sullivans Creek Road, Acton, ACT, 2601, Australia.
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5
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Wei Z, Duan F, Sun X, Song X, Zhou W. Leaf photosynthetic and anatomical insights into mechanisms of acclimation in rice in response to long-term fluctuating light. PLANT, CELL & ENVIRONMENT 2021; 44:747-761. [PMID: 33215722 DOI: 10.1111/pce.13954] [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: 09/01/2020] [Accepted: 11/09/2020] [Indexed: 05/18/2023]
Abstract
Long-term fluctuating light (FL) conditions are very common in natural environments. The physiological and biochemical mechanisms for acclimation to FL differ between species. However, most of the current conclusions regarding acclimation to FL were made based on studies in algae or Arabidopsis thaliana. It is still unclear how rice (Oryza sativa L.) integrate multiple physiological changes to acclimate to long-term FL. In this study, we found that rice growth was repressed under long-term FL. By systematically measuring phenotypes and physiological parameters, we revealed that: (a) under short-term FL, photosystem I (PSI) was inhibited, while after 1-7 days of long-term FL, both PSI and PSII were inhibited. Higher acceptor-side limitation in electron transport and higher overall nonphotochemical quenching (NPQ) explained the lower efficiencies of PSI and PSII, respectively. (b) An increase in pH differences across the thylakoid membrane and a decrease in thylakoid proton conductivity revealed a reduction of ATP synthase activity. (c) Using electron microscopy, we showed a decrease in membrane stacking and stomatal opening after 7 days of FL treatment. Taken together, our results show that electron flow, ATP synthase activity and NPQ regulation are the major processes determining the growth performance of rice under long-term FL conditions.
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Affiliation(s)
- Ze Wei
- State Key Laboratory of Crop Biology/Agronomy College, Shandong Agricultural University, Taian, China
- State Key Laboratory of Crop Physiology and Ecology, Ministry of Agriculture and Rural Affairs of China, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Fengying Duan
- State Key Laboratory of Crop Physiology and Ecology, Ministry of Agriculture and Rural Affairs of China, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xuezhen Sun
- State Key Laboratory of Crop Biology/Agronomy College, Shandong Agricultural University, Taian, China
| | - Xianliang Song
- State Key Laboratory of Crop Biology/Agronomy College, Shandong Agricultural University, Taian, China
| | - Wenbin Zhou
- State Key Laboratory of Crop Physiology and Ecology, Ministry of Agriculture and Rural Affairs of China, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
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6
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Yanhui C, Hongrui W, Beining Z, Shixing G, Zihan W, Yue W, Huihui Z, Guangyu S. Elevated air temperature damage to photosynthetic apparatus alleviated by enhanced cyclic electron flow around photosystem I in tobacco leaves. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 204:111136. [PMID: 32798755 DOI: 10.1016/j.ecoenv.2020.111136] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 08/03/2020] [Accepted: 08/04/2020] [Indexed: 06/11/2023]
Abstract
High temperature can lead to increased production of excess light energy, thus reducing photosynthetic capacity in plants. Photosynthetic cyclic electron flow (CEF) in photosystem I (PSI) can effectively protect photosystems, but its physiological mechanism under high temperature is poorly understood. In this study, antimycin A (AA) and thenoyltrifluoroacetone (TTFA) were used to inhibit PGR5-and NDH-dependent CEF pathways, respectively, to reveal the photoprotective functions of CEF for PSII in tobacco leaves under high temperature stress (37 °C, HT). High temperatures caused decreases in maximal photochemistry efficiency (Fv/Fm) and damaged photosystem II (PSII) in tobacco leaves. Under AA inhibition of PGR5-dependent CEF, high temperature increased the fluorescence intensity of point O (Fo) in OJIP curves, i.e., the energy absorption per active reaction center (ABS/RC), the trapping rate of the reaction center (TRo/RC), and the electron transport efficiency per reaction center (ETo/RC) in tobacco leaves. High temperature induced an increase in the hydrogen peroxide content and a decrease in pigment content in tobacco leaves. Under the high temperature treatment, inhibition of PGR5-dependent CEF reduced the activities of the PSII reaction center significantly, destroyed the oxygen-evolving complex (OEC), and impeded photosynthetic electron transfer from PSII to the plastoquinone (PQ) pool in tobacco leaves. The TTFA treatment inhibited the NDH-dependent pathway under high temperature conditions, with the relative fluorescence intensity of point I (VI) decreased significantly, and the content of hydrogen peroxide and superoxide anion increased significantly. Additionally, Fo and the redox degree of the PSII donor side (Wk) increased, and pigment content decreased compared to the control, but with little change compared to high temperature treatment, indicating that the inhibition of the NDH-dependent pathway directly weakened the capacity of the PQ pool to lead to the accumulation of reactive oxygen species (ROS) in tobacco leaves. In conclusion, CEF alleviated damage to the photosynthetic apparatus in tobacco leaves by increasing PSII heat dissipation, reducing ROS production, and maintaining the stability of the PQ pool to accommodate photosynthetic electron flow.
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Affiliation(s)
- Che Yanhui
- Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, College of Life Sciences, Northeast Forestry University, Harbin, 150040, China
| | - Wang Hongrui
- Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, College of Life Sciences, Northeast Forestry University, Harbin, 150040, China
| | - Zhang Beining
- Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, College of Life Sciences, Northeast Forestry University, Harbin, 150040, China
| | - Gao Shixing
- Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, College of Life Sciences, Northeast Forestry University, Harbin, 150040, China
| | - Wang Zihan
- Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, College of Life Sciences, Northeast Forestry University, Harbin, 150040, China
| | - Wang Yue
- Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, College of Life Sciences, Northeast Forestry University, Harbin, 150040, China
| | - Zhang Huihui
- Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, College of Life Sciences, Northeast Forestry University, Harbin, 150040, China; College of Resources and Environment, Northeast Agricultural University, Harbin Heilongjiang, China
| | - Sun Guangyu
- Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, College of Life Sciences, Northeast Forestry University, Harbin, 150040, China.
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Yin X, Niu Y, van der Putten PEL, Struik PC. The Kok effect revisited. THE NEW PHYTOLOGIST 2020; 227:1764-1775. [PMID: 32369617 PMCID: PMC7497127 DOI: 10.1111/nph.16638] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 04/24/2020] [Indexed: 05/18/2023]
Abstract
The Kok effect refers to the abrupt decrease around the light compensation point in the slope of net photosynthetic rate vs irradiance. Arguably, this switch arises from light inhibition of respiration, allowing the Kok method to estimate day respiration (Rd ). Recent analysis suggests that increasing proportions of photorespiration (quantified as Γ*/Cc , the ratio of CO2 compensation point Γ* to chloroplast CO2 concentration, Cc ) with irradiance explain much of the Kok effect. Also, the Kok method has been modified to account for the decrease in PSII photochemical efficiency (Φ2 ) with irradiance. Using a model that illustrates how varying Rd , Γ*/Cc , Φ2 and proportions of alternative electron transport could engender the Kok effect, we quantified the contribution of these parameters to the Kok effect measured in sunflower across various O2 and CO2 concentrations and various temperatures. Overall, the decreasing Φ2 with irradiance explained c. 12%, and the varying Γ*/Cc explained c. 25%, of the Kok effect. Maximum real light inhibition of Rd was much lower than the inhibition derived from the Kok method, but still increased with photorespiration. Photorespiration had a dual contribution to the Kok effect, one via the varying Γ*/Cc and the other via its participation in light inhibition of Rd .
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Affiliation(s)
- Xinyou Yin
- Centre for Crop Systems AnalysisDepartment of Plant SciencesWageningen University & ResearchPO Box 430Wageningen6700 AKthe Netherlands
| | - Yuxi Niu
- Centre for Crop Systems AnalysisDepartment of Plant SciencesWageningen University & ResearchPO Box 430Wageningen6700 AKthe Netherlands
| | - Peter E. L. van der Putten
- Centre for Crop Systems AnalysisDepartment of Plant SciencesWageningen University & ResearchPO Box 430Wageningen6700 AKthe Netherlands
| | - Paul C. Struik
- Centre for Crop Systems AnalysisDepartment of Plant SciencesWageningen University & ResearchPO Box 430Wageningen6700 AKthe Netherlands
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Huihui Z, Yue W, Xin L, Guoqiang H, Yanhui C, Zhiyuan T, Jieyu S, Nan X, Guangyu S. Chlorophyll synthesis and the photoprotective mechanism in leaves of mulberry (Morus alba L.) seedlings under NaCl and NaHCO 3 stress revealed by TMT-based proteomics analyses. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 190:110164. [PMID: 31927191 DOI: 10.1016/j.ecoenv.2020.110164] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 12/12/2019] [Accepted: 01/02/2020] [Indexed: 05/20/2023]
Abstract
Chlorophyll (Chl) and effective photoprotective mechanism are important prerequisites to ensure the photosynthetic function of plants under stress. In this study, the effects of 100 mmol L-1 NaCl and NaHCO3 stress on chlorophyll synthesis and photosynthetic function of mulberry seedlings were studied by physiological combined with proteomics technology. The results show that: NaCl stress had little effect on the expression of Chl synthesis related proteins, and there were no significant changes in Chl content and Chl a:b ratio. However, 13 of the 15 key proteins in the process of Chl synthesis were significantly decreased under NaHCO3 stress, and the contents of Chl a and Chl b were significantly decreased (especially Chl a). Although stomatal conductance (Gs) decreased significantly under NaCl stress, net photosynthetic rate (Pn), PSII maximum photochemical efficiency (Fv/Fm) and electron transfer rate (ETR) did not change significantly, but under NaHCO3 stress, not only Gs decreased significantly, PSII activity and photosynthetic carbon were the same. In the photoprotective mechanism under NaCl stress, NAD(P)H dehydrogenase (NDH)-dependent cyclic electron flow (CEF) enhanced, the expression of related proteins subunit, ndhH, ndhI, ndhK, and ndhM, the key enzyme of the xanthophyll cycle, violaxanthin de-epoxidase (VDE) were up-regulated, the ratio of (A + Z)/(V + A + Z) and non-photochemical quenching (NPQ) was increased. The expressions of proteins FTR and Fd-NiR were also significant up-regulated under NaCl stress, Fd-dependent ROS metabolism and nitrogen metabolism can effectively reduce the electronic pressure on Fd. Under NaHCO3 stress, the expressions of NDH-dependent CEF related proteins subunit (ndhH, ndhI, ndhK, ndhM and ndhN), VDE, ZE, FTR, Fd-NiR and Fd-GOGAT, were significant down-regulated, and ZE, CP26, ndhK, ndhM, Fd-NiR, Fd-GOGAT and FTR genes expression also significantly decreased, the photoprotective mechanism, like the xanthophyll cycle,CEF and Fd-dependent ROS metabolism and nitrogen metabolism might be damaged, resulting in the inhibition of PSII electron transfer and carbon assimilation in mulberry leaves under NaHCO3 stress.
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Affiliation(s)
- Zhang Huihui
- College of Resources and Environment, Northeast Agricultural University, Harbin, Heilongjiang, China; Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, College of Life Sciences, Northeast Forestry University, Harbin, Heilongjiang, China
| | - Wang Yue
- Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, College of Life Sciences, Northeast Forestry University, Harbin, Heilongjiang, China
| | - Li Xin
- College of Resources and Environment, Northeast Agricultural University, Harbin, Heilongjiang, China; Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, College of Life Sciences, Northeast Forestry University, Harbin, Heilongjiang, China
| | - He Guoqiang
- Mudanjang Tobacco Science Research Institute, Mudanjang, Heilongjiang, China
| | - Che Yanhui
- Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, College of Life Sciences, Northeast Forestry University, Harbin, Heilongjiang, China
| | - Teng Zhiyuan
- Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, College of Life Sciences, Northeast Forestry University, Harbin, Heilongjiang, China
| | - Shao Jieyu
- Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, College of Life Sciences, Northeast Forestry University, Harbin, Heilongjiang, China
| | - Xu Nan
- Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, College of Life Sciences, Northeast Forestry University, Harbin, Heilongjiang, China; Natural Resources and Ecology Institute, Heilongjiang Sciences Academy, Harbin, Heilongjiang, China.
| | - Sun Guangyu
- Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, College of Life Sciences, Northeast Forestry University, Harbin, Heilongjiang, China.
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Sagun JV, Badger MR, Chow WS, Ghannoum O. Cyclic electron flow and light partitioning between the two photosystems in leaves of plants with different functional types. PHOTOSYNTHESIS RESEARCH 2019; 142:321-334. [PMID: 31520186 PMCID: PMC6874625 DOI: 10.1007/s11120-019-00666-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 08/26/2019] [Indexed: 05/05/2023]
Abstract
Cyclic electron flow (CEF) around photosystem I (PSI) is essential for generating additional ATP and enhancing efficient photosynthesis. Accurate estimation of CEF requires knowledge of the fractions of absorbed light by PSI (fI) and PSII (fII), which are only known for a few model species such as spinach. No measures of fI are available for C4 grasses under different irradiances. We developed a new method to estimate (1) fII in vivo by concurrently measuring linear electron flux through both photosystems [Formula: see text] in leaf using membrane inlet mass spectrometry (MIMS) and total electron flux through PSII (ETR2) using chlorophyll fluorescence by a Dual-PAM at low light and (2) CEF as ETR1-[Formula: see text]. For a C3 grass, fI was 0.5 and 0.4 under control (high light) and shade conditions, respectively. C4 species belonging to NADP-ME and NAD-ME subtypes had fI of 0.6 and PCK subtype had 0.5 under control. All shade-grown C4 species had fI of 0.6 except for NADP-ME grass which had 0.7. It was also observed that fI ranged between 0.3 and 0.5 for gymnosperm, liverwort and fern species. CEF increased with irradiance and was induced at lower irradiances in C4 grasses and fern relative to other species. CEF was greater in shade-grown plants relative to control plants except for C4 NADP-ME species. Our study reveals a range of CEF and fI values in different plant functional groups. This variation must be taken into account for improved photosynthetic calculations and modelling.
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Affiliation(s)
- Julius Ver Sagun
- ARC Centre of Excellence for Translational Photosynthesis, Hawkesbury Institute for the Environment, Western Sydney University, Hawkesbury Campus, Locked Bag 1797, Penrith, NSW 2751 Australia
| | - Murray R. Badger
- ARC Centre of Excellence for Translational Photosynthesis, Research School of Biology, Australian National University, Canberra, ACT 2601 Australia
| | - Wah Soon Chow
- ARC Centre of Excellence for Translational Photosynthesis, Research School of Biology, Australian National University, Canberra, ACT 2601 Australia
| | - Oula Ghannoum
- ARC Centre of Excellence for Translational Photosynthesis, Hawkesbury Institute for the Environment, Western Sydney University, Hawkesbury Campus, Locked Bag 1797, Penrith, NSW 2751 Australia
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10
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Hui-Hui Z, Guang-Liang S, Jie-Yu S, Xin L, Ma-Bo L, Liang M, Nan X, Guang-Yu S. Photochemistry and proteomics of mulberry (Morus alba L.) seedlings under NaCl and NaHCO 3 stress. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2019; 184:109624. [PMID: 31487570 DOI: 10.1016/j.ecoenv.2019.109624] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 08/16/2019] [Accepted: 08/28/2019] [Indexed: 05/20/2023]
Abstract
In order to explore the response and adaptation mechanisms of photosynthesis of the leaves of mulberry (Morus alba L.) seedlings to saline-alkali stress. Photosynthetic activity, and the response of related proteomics of M. alba seedling leaves under NaCl and NaHCO3 stress were studied by using chlorophyll fluorescence and gas exchange technique combined with TMT proteomics. The results showed that NaCl stress had no significant effect on photosystem II (PSII) activity in M. alba seedling leaves. In addition, the expressions of proteins of the PSII oxygen-evolving complex (OEE3-1 and PPD4) and the LHCII antenna (CP24 10A, CP26, and CP29) were increased, and the photosystem I (PSI) activity in the leaves of M. alba seedlings was increased, as well as expressions of proteins, such as PsaF, PsaG, PsaH, PsaL, PsaN, and Ycf4. Under NaHCO3 stress, the activity of PSII and PSI and the expression of their protein complexes and the electron transfer-related proteins significantly decreased. NaCl stress had little effect on RuBP regeneration during dark reaction in the leaves and the expressions of glucose synthesis related proteins and net photosynthetic rate (Pn) did not decrease significantly. The leaves could adapt to NaCl stress by reducing stomatal conductance (Gs) and increasing water use efficiency (WUE). Under NaHCO3 stress, the expression of dark reaction-related proteins was mostly down-regulated, while Gs was reduced, which indicated that non-stomatal factors can be responsible for inhibition of carbon assimilation.
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Affiliation(s)
- Zhang Hui-Hui
- College of Resources and Environment, Northeast Agricultural University, Harbin, Heilongjiang, China
| | - Shi Guang-Liang
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, Heilongjiang, China
| | - Shao Jie-Yu
- College of Life Sciences, Northeast Forestry University, Harbin, Heilongjiang, China
| | - Li Xin
- College of Resources and Environment, Northeast Agricultural University, Harbin, Heilongjiang, China
| | - Li Ma-Bo
- College of Resources and Environment, Northeast Agricultural University, Harbin, Heilongjiang, China
| | - Meng Liang
- College of Resources and Environment, Northeast Agricultural University, Harbin, Heilongjiang, China
| | - Xu Nan
- College of Life Sciences, Northeast Forestry University, Harbin, Heilongjiang, China; Natural Resources and Ecology Institute, Heilongjiang Sciences Academy, Harbin, Heilongjiang, China.
| | - Sun Guang-Yu
- College of Life Sciences, Northeast Forestry University, Harbin, Heilongjiang, China.
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11
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Zhang MM, Fan DY, Murakami K, Badger MR, Sun GY, Chow WS. Partially Dissecting Electron Fluxes in Both Photosystems in Spinach Leaf Disks during Photosynthetic Induction. PLANT & CELL PHYSIOLOGY 2019; 60:2206-2219. [PMID: 31271439 DOI: 10.1093/pcp/pcz114] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Accepted: 05/29/2019] [Indexed: 06/09/2023]
Abstract
Photosynthetic induction, a gradual increase in photosynthetic rate on a transition from darkness or low light to high light, has ecological significance, impact on biomass accumulation in fluctuating light and relevance to photoprotection in strong light. However, the experimental quantification of the component electron fluxes in and around both photosystems during induction has been rare. Combining optimized chlorophyll fluorescence, the redox kinetics of P700 [primary electron donor in Photosystem I (PSI)] and membrane inlet mass spectrometry in the absence/presence of inhibitors/mediator, we partially estimated the components of electron fluxes in spinach leaf disks on transition from darkness to 1,000 �mol photons�m-2�s-1 for up to 10 min, obtaining the following findings: (i) the partitioning of energy between both photosystems did not change noticeably; (ii) in Photosystem II (PSII), the combined cyclic electron flow (CEF2) and charge recombination (CR2) to the ground state decreased gradually toward 0 in steady state; (iii) oxygen reduction by electrons from PSII, partly bypassing PSI, was small but measurable; (iv) cyclic electron flow around PSI (CEF1) peaked before becoming somewhat steady; (v) peak magnitudes of some of the electron fluxes, all probably photoprotective, were in the descending order: CEF1 > CEF2 + CR2 > chloroplast O2 uptake; and (vi) the chloroplast NADH dehydrogenase-like complex appeared to aid the antimycin A-sensitive CEF1. The results are important for fine-tuning in silico simulation of in vivo photosynthetic electron transport processes; such simulation is, in turn, necessary to probe partial processes in a complex network of interactions in response to environmental changes.
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Affiliation(s)
- Meng-Meng Zhang
- Department of Plant Physiology, College of Life Science, Northeast Forestry University, Harbin, Heilongjiang, China
- Division of Plant Sciences, Research School of Biology, The Australian National University, Acton, ACT, Australia
| | - Da-Yong Fan
- Division of Plant Sciences, Research School of Biology, The Australian National University, Acton, ACT, Australia
- College of Forestry, Beijing Forestry University, Beijing, China
| | - Keach Murakami
- Division of Plant Sciences, Research School of Biology, The Australian National University, Acton, ACT, Australia
- National Agriculture and Food Research Organization (NARO), Hokkaido Agricultural Research Center (HARC), Hitsujigaoka 1, Toyohira, Sapporo, Japan
| | - Murray R Badger
- ARC Centre of Excellence for Translational Photosynthesis, Research School of Biology, The Australian National University, Acton, ACT, Australia
| | - Guang-Yu Sun
- Department of Plant Physiology, College of Life Science, Northeast Forestry University, Harbin, Heilongjiang, China
| | - Wah Soon Chow
- ARC Centre of Excellence for Translational Photosynthesis, Research School of Biology, The Australian National University, Acton, ACT, Australia
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