1
|
Naschberger A, Fadeeva M, Klaiman D, Borovikova-Sheinker A, Caspy I, Nelson N, Amunts A. Structure of plant photosystem I in a native assembly state defines PsaF as a regulatory checkpoint. NATURE PLANTS 2024:10.1038/s41477-024-01699-8. [PMID: 38816499 DOI: 10.1038/s41477-024-01699-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 04/12/2024] [Indexed: 06/01/2024]
Abstract
Plant photosystem I (PSI) consists of at least 13 nuclear-encoded and 4 chloroplast-encoded subunits that together act as a sunlight-driven oxidoreductase. Here we report the structure of a PSI assembly intermediate that we isolated from greening oat seedlings. The assembly intermediate shows an absence of at least eight subunits, including PsaF and LHCI, and lacks photoreduction activity. The data show that PsaF is a regulatory checkpoint that promotes the assembly of LHCI, effectively coupling biogenesis to function.
Collapse
Affiliation(s)
- Andreas Naschberger
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, Solna, Sweden
| | - Mariia Fadeeva
- The George S. Wise Faculty of Life Sciences, Department of Biochemistry and Molecular Biology, Tel Aviv University, Tel Aviv, Israel
| | - Daniel Klaiman
- The George S. Wise Faculty of Life Sciences, Department of Biochemistry and Molecular Biology, Tel Aviv University, Tel Aviv, Israel
| | - Anna Borovikova-Sheinker
- The George S. Wise Faculty of Life Sciences, Department of Biochemistry and Molecular Biology, Tel Aviv University, Tel Aviv, Israel
| | - Ido Caspy
- The George S. Wise Faculty of Life Sciences, Department of Biochemistry and Molecular Biology, Tel Aviv University, Tel Aviv, Israel
| | - Nathan Nelson
- The George S. Wise Faculty of Life Sciences, Department of Biochemistry and Molecular Biology, Tel Aviv University, Tel Aviv, Israel.
| | - Alexey Amunts
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, Solna, Sweden.
- Westlake University, Hangzhou, China.
| |
Collapse
|
2
|
Melicher P, Dvořák P, Řehák J, Šamajová O, Pechan T, Šamaj J, Takáč T. Methyl viologen-induced changes in the Arabidopsis proteome implicate PATELLIN 4 in oxidative stress responses. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:405-421. [PMID: 37728561 PMCID: PMC10735431 DOI: 10.1093/jxb/erad363] [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: 06/21/2023] [Accepted: 09/12/2023] [Indexed: 09/21/2023]
Abstract
The photosynthesis-induced accumulation of reactive oxygen species in chloroplasts can lead to oxidative stress, triggering changes in protein synthesis, degradation, and the assembly/disassembly of protein complexes. Using shot-gun proteomics, we identified methyl viologen-induced changes in protein abundance in wild-type Arabidopsis and oxidative stress-hypersensitive fsd1-1 and fsd1-2 knockout mutants, which are deficient in IRON SUPEROXIDE DISMUTASE 1 (FSD1). The levels of proteins that are localized in chloroplasts and the cytoplasm were modified in all lines treated with methyl viologen. Compared with the wild-type, fsd1 mutants showed significant changes in metabolic protein and chloroplast chaperone levels, together with increased ratio of cytoplasmic, peroxisomal, and mitochondrial proteins. Different responses in proteins involved in the disassembly of photosystem II-light harvesting chlorophyll a/b binding proteins were observed. Moreover, the abundance of PATELLIN 4, a phospholipid-binding protein enriched in stomatal lineage, was decreased in response to methyl viologen. Reverse genetic studies using patl4 knockout mutants and a PATELLIN 4 complemented line indicate that PATELLIN 4 affects plant responses to oxidative stress by effects on stomatal closure.
Collapse
Affiliation(s)
- Pavol Melicher
- Department of Biotechnology, Faculty of Science, Palacký University Olomouc, Olomouc, Czech Republic
| | - Petr Dvořák
- Department of Biotechnology, Faculty of Science, Palacký University Olomouc, Olomouc, Czech Republic
| | - Jan Řehák
- Department of Biotechnology, Faculty of Science, Palacký University Olomouc, Olomouc, Czech Republic
| | - Olga Šamajová
- Department of Biotechnology, Faculty of Science, Palacký University Olomouc, Olomouc, Czech Republic
| | - Tibor Pechan
- Institute for Genomics, Biocomputing and Biotechnology, Mississippi Agricultural and Forestry Experiment Station, Mississippi State University, Starkville, MS, USA
| | - Jozef Šamaj
- Department of Biotechnology, Faculty of Science, Palacký University Olomouc, Olomouc, Czech Republic
| | - Tomáš Takáč
- Department of Biotechnology, Faculty of Science, Palacký University Olomouc, Olomouc, Czech Republic
| |
Collapse
|
3
|
Ribeiro DG, Bezerra ACM, Santos IR, Grynberg P, Fontes W, de Souza Castro M, de Sousa MV, Lisei-de-Sá ME, Grossi-de-Sá MF, Franco OL, Mehta A. Proteomic Insights of Cowpea Response to Combined Biotic and Abiotic Stresses. PLANTS (BASEL, SWITZERLAND) 2023; 12:plants12091900. [PMID: 37176957 PMCID: PMC10180824 DOI: 10.3390/plants12091900] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 04/19/2023] [Accepted: 04/25/2023] [Indexed: 05/15/2023]
Abstract
The co-occurrence of biotic and abiotic stresses in agricultural areas severely affects crop performance and productivity. Drought is one of the most adverse environmental stresses, and its association with root-knot nematodes further limits the development of several economically important crops, such as cowpea. Plant responses to combined stresses are complex and require novel adaptive mechanisms through the induction of specific biotic and abiotic signaling pathways. Therefore, the present work aimed to identify proteins involved in the resistance of cowpea to nematode and drought stresses individually and combined. We used the genotype CE 31, which is resistant to the root-knot nematode Meloidogyne spp. And tolerant to drought. Three biological replicates of roots and shoots were submitted to protein extraction, and the peptides were evaluated by LC-MS/MS. Shotgun proteomics revealed 2345 proteins, of which 1040 were differentially abundant. Proteins involved in essential biological processes, such as transcriptional regulation, cell signaling, oxidative processes, and photosynthesis, were identified. However, the main defense strategies in cowpea against cross-stress are focused on the regulation of hormonal signaling, the intense production of pathogenesis-related proteins, and the downregulation of photosynthetic activity. These are key processes that can culminate in the adaptation of cowpea challenged by multiple stresses. Furthermore, the candidate proteins identified in this study will strongly contribute to cowpea genetic improvement programs.
Collapse
Affiliation(s)
- Daiane Gonzaga Ribeiro
- Centro de Análises Proteômicas e Bioquímicas Programa de Pós-Graduação em Ciências Genômicas e Biotecnologia, Universidade Católica de Brasília (UCB), Brasília CEP 71966-700, DF, Brazil
| | | | - Ivonaldo Reis Santos
- Programa de Pós-Graduação em Ciências Biológicas (Biologia Molecular), Instituto de Ciências Biológicas, Campus Universitário Darcy Ribeiro-UnB, Universidade de Brasília, Brasília CEP 70910-900, DF, Brazil
| | - Priscila Grynberg
- Embrapa Recursos Genéticos e Biotecnologia, PBI, Av. W/5 Norte Final, Brasília CEP 70770-917, DF, Brazil
| | - Wagner Fontes
- Laboratório de Bioquímica e Química de Proteínas, Departamento de Biologia Celular, Universidade de Brasília, Brasília CEP 70910-900, DF, Brazil
| | - Mariana de Souza Castro
- Laboratório de Bioquímica e Química de Proteínas, Departamento de Biologia Celular, Universidade de Brasília, Brasília CEP 70910-900, DF, Brazil
| | - Marcelo Valle de Sousa
- Laboratório de Bioquímica e Química de Proteínas, Departamento de Biologia Celular, Universidade de Brasília, Brasília CEP 70910-900, DF, Brazil
| | - Maria Eugênia Lisei-de-Sá
- Embrapa Recursos Genéticos e Biotecnologia, PBI, Av. W/5 Norte Final, Brasília CEP 70770-917, DF, Brazil
| | - Maria Fatima Grossi-de-Sá
- Centro de Análises Proteômicas e Bioquímicas Programa de Pós-Graduação em Ciências Genômicas e Biotecnologia, Universidade Católica de Brasília (UCB), Brasília CEP 71966-700, DF, Brazil
- Embrapa Recursos Genéticos e Biotecnologia, PBI, Av. W/5 Norte Final, Brasília CEP 70770-917, DF, Brazil
- National Institute of Science and Technology, INCT PlantStress Biotech, Embrapa, Brasilia CEP 70770-917, DF, Brazil
| | - Octávio Luiz Franco
- Centro de Análises Proteômicas e Bioquímicas Programa de Pós-Graduação em Ciências Genômicas e Biotecnologia, Universidade Católica de Brasília (UCB), Brasília CEP 71966-700, DF, Brazil
- S-Inova Biotech, Universidade Católica Dom Bosco (UCDB), Campo Grande CEP 79117-900, MS, Brazil
| | - Angela Mehta
- Embrapa Recursos Genéticos e Biotecnologia, PBI, Av. W/5 Norte Final, Brasília CEP 70770-917, DF, Brazil
| |
Collapse
|
4
|
Su X, Yan S, Zhao W, Liu H, Jiang Q, Wei Y, Guo H, Yin M, Shen J, Cheng H. Self-assembled thiophanate-methyl/star polycation complex prevents plant cell-wall penetration and fungal carbon utilization during cotton infection by Verticillium dahliae. Int J Biol Macromol 2023; 239:124354. [PMID: 37028625 DOI: 10.1016/j.ijbiomac.2023.124354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 03/23/2023] [Accepted: 04/03/2023] [Indexed: 04/08/2023]
Abstract
No effective fungicides are available for the management of Verticillium dahliae, which causes vascular wilt disease. In this study, a star polycation (SPc)-based nanodelivery system was used for the first time to develop a thiophanate-methyl (TM) nanoagent for the management of V. dahliae. SPc spontaneously assembled with TM through hydrogen bonding and Van der Waals forces to decrease the particle size of TM from 834 to 86 nm. Compared to TM alone, the SPc-loaded TM further reduced the colony diameter of V. dahliae to 1.12 and 0.64 cm, and the spore number to 1.13 × 108 and 0.72 × 108 cfu/mL at the concentrations of 3.77 and 4.71 mg/L, respectively. The TM nanoagents disturbed the expression of various crucial genes in V. dahliae, and contributed to preventing plant cell-wall degradation and carbon utilization by V. dahliae, which mainly impaired the infective interaction between pathogens and plants. TM nanoagents remarkably decreased the plant disease index and the fungal biomass in the root compared to TM alone, and its control efficacy was the best (61.20 %) among the various formulations tested in the field. Furthermore, SPc showed negligible acute toxicity toward cotton seeds. To the best of our knowledge, this study is the first to design a self-assembled nanofungicide that efficiently inhibits V. dahliae growth and protects cotton from the destructive Verticillium wilt.
Collapse
Affiliation(s)
- Xiaofeng Su
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China; Western Agricultural Research Center, Chinese Academy of Agricultural Sciences, Changji 831100, PR China
| | - Shuo Yan
- Department of Plant Biosecurity and MARA Key Laboratory of Surveillance and Management for Plant Quarantine Pests, College of Plant Protection, China Agricultural University, Beijing 100193, PR China.
| | - Weisong Zhao
- Institute of Plant Protection, Hebei Academy of Agriculture and Forestry Sciences, Baoding 071000, PR China
| | - Haiyang Liu
- Institute of Plant Protection, Xinjiang Academy of Agricultural Sciences, Urumqi 830091, PR China
| | - Qinhong Jiang
- Department of Plant Biosecurity and MARA Key Laboratory of Surveillance and Management for Plant Quarantine Pests, College of Plant Protection, China Agricultural University, Beijing 100193, PR China
| | - Ying Wei
- Department of Plant Biosecurity and MARA Key Laboratory of Surveillance and Management for Plant Quarantine Pests, College of Plant Protection, China Agricultural University, Beijing 100193, PR China
| | - Huiming Guo
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China; Western Agricultural Research Center, Chinese Academy of Agricultural Sciences, Changji 831100, PR China
| | - Meizhen Yin
- State Key Laboratory of Chemical Resource Engineering, Beijing Lab of Biomedical Materials, Beijing University of Chemical Technology, Beijing 100029, PR China
| | - Jie Shen
- Department of Plant Biosecurity and MARA Key Laboratory of Surveillance and Management for Plant Quarantine Pests, College of Plant Protection, China Agricultural University, Beijing 100193, PR China.
| | - Hongmei Cheng
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China; Western Agricultural Research Center, Chinese Academy of Agricultural Sciences, Changji 831100, PR China.
| |
Collapse
|
5
|
Gao P, Xia H, Li Q, Li Z, Zhai C, Weng L, Mi H, Yan S, Datla R, Wang H, Yang J. PALE-GREEN LEAF 1, a rice cpSRP54 protein, is essential for the assembly of the PSI-LHCI supercomplex. PLANT DIRECT 2022; 6:e436. [PMID: 35949951 PMCID: PMC9358330 DOI: 10.1002/pld3.436] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 06/17/2022] [Accepted: 07/19/2022] [Indexed: 05/27/2023]
Abstract
Although photosynthetic multiprotein complexes have received major attention, our knowledge about the assembly of these proteins into functional complexes in plants is still limited. In the present study, we have identified a chlorophyll-deficient mutant, pale-green leaf 1 (pgl1), in rice that displays abnormally developed chloroplasts. Map-based cloning of this gene revealed that OsPGL1 encodes a chloroplast targeted protein homologous to the 54-kDa subunit of the signal recognition particle (cpSRP54). Immunoblot analysis revealed that the accumulation of the PSI core proteins PsaA and PsaB, subunits from the ATP synthase, cytochrome, and light-harvesting complex (LHC) is dramatically reduced in pgl1. Blue native gel analysis of thylakoid membrane proteins showed the existence of an extra band in the pgl1 mutant, which located between the dimeric PSII/PSI-LHCI and the monomeric PSII. Immunodetection after 2D separation indicated that the extra band consists of the proteins from the PSI core complex. Measurements of chlorophyll fluorescence at 77 K further confirmed that PSI, rather than PSII, was primarily impaired in the pgl1 mutant. These results suggest that OsPGL1 might act as a molecular chaperone that is required for the efficient assembly and specific integration of the peripheral LHCI proteins into the PSI core complex in rice.
Collapse
Affiliation(s)
- Peng Gao
- Saskatoon Research and Development CentreAgriculture and Agri‐food CanadaSaskatoonSKCanada
| | - Haoqiang Xia
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghaiChina
| | - Qiang Li
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanChina
| | - Zongzhu Li
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghaiChina
| | - Chun Zhai
- Saskatoon Research and Development CentreAgriculture and Agri‐food CanadaSaskatoonSKCanada
| | - Lin Weng
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghaiChina
| | - Hualing Mi
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghaiChina
| | - Song Yan
- Rice Research InstituteJiangxi Academy of Agricultural SciencesNanchangChina
| | - Raju Datla
- Global Institute for Food SecurityUniversity of SaskatchewanSaskatoonSKCanada
| | - Hua Wang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro‐products, Institute of Virology and BiotechnologyZhejiang Academy of Agricultural SciencesHangzhouChina
| | - Jun Yang
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghaiChina
| |
Collapse
|
6
|
Lin N, Gao Y, Zhou Q, Ping X, Li J, Liu L, Yin J. Genetic mapping and physiological analysis of chlorophyll-deficient mutant in Brassica napus L. BMC PLANT BIOLOGY 2022; 22:244. [PMID: 35585493 PMCID: PMC9115954 DOI: 10.1186/s12870-022-03630-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Accepted: 05/04/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND Leaf color mutants have reduced photosynthetic efficiency, which has severely negative impacts on crop growth and economic product yield. There are different chlorophyll mutants in Arabidopsis and crops that can be used for genetic control and molecular mechanism studies of chlorophyll biosynthesis, chloroplast development and photoefficiency. Chlorophyll mutants in Brassica napus are mostly used for mapping and location research but are rarely used for physiological research. The chlorophyll-deficient mutant in this experiment were both genetically mapped and physiologically analyzed. RESULTS In this study, yellow leaf mutant of Brassica napus L. mutated by ethyl methyl sulfone (EMS) had significantly lower chlorophyll a, b and carotenoid contents than the wild type, and the net photosynthetic efficiency, stomatal conductance and transpiration rate were all significantly reduced. The mutant had sparse chloroplast distribution and weak autofluorescence. The granule stacks were reduced, and the shape was extremely irregular, with more broken stromal lamella. Transcriptome data analysis enriched the differentially expressed genes mainly in phenylpropane and sugar metabolism. The mutant was mapped to a 2.72 Mb region on A01 by using BSA-Seq, and the region was validated by SSR markers. CONCLUSIONS The mutant chlorophyll content and photosynthetic efficiency were significantly reduced compared with those of the wild type. Abnormal chloroplasts and thylakoids less connected to the stroma lamella appeared in the mutant. This work on the mutant will facilitate the process of cloning the BnaA01.cd gene and provide more genetic and physiological information concerning chloroplast development in Brassica napus.
Collapse
Affiliation(s)
- Na Lin
- College of Agronomy and Biotechnology, Southwest University, Beibei, Chongqing, 400715, PR China
| | - Yumin Gao
- College of Agronomy and Biotechnology, Southwest University, Beibei, Chongqing, 400715, PR China
| | - Qingyuan Zhou
- College of Agronomy and Biotechnology, Southwest University, Beibei, Chongqing, 400715, PR China
| | - Xiaoke Ping
- College of Agronomy and Biotechnology, Southwest University, Beibei, Chongqing, 400715, PR China
- Academy of Agricultural Sciences, Southwest University, Tiansheng Rd2#, Beibei, Chongqing, 400715, PR China
| | - Jiana Li
- College of Agronomy and Biotechnology, Southwest University, Beibei, Chongqing, 400715, PR China
- Academy of Agricultural Sciences, Southwest University, Tiansheng Rd2#, Beibei, Chongqing, 400715, PR China
| | - Liezhao Liu
- College of Agronomy and Biotechnology, Southwest University, Beibei, Chongqing, 400715, PR China
- Academy of Agricultural Sciences, Southwest University, Tiansheng Rd2#, Beibei, Chongqing, 400715, PR China
| | - Jiaming Yin
- College of Agronomy and Biotechnology, Southwest University, Beibei, Chongqing, 400715, PR China.
| |
Collapse
|
7
|
Gisriel CJ, Flesher DA, Shen G, Wang J, Ho MY, Brudvig GW, Bryant DA. Structure of a photosystem I-ferredoxin complex from a marine cyanobacterium provides insights into far-red light photoacclimation. J Biol Chem 2022; 298:101408. [PMID: 34793839 PMCID: PMC8689207 DOI: 10.1016/j.jbc.2021.101408] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 11/08/2021] [Accepted: 11/09/2021] [Indexed: 01/08/2023] Open
Abstract
Far-red light photoacclimation exhibited by some cyanobacteria allows these organisms to use the far-red region of the solar spectrum (700-800 nm) for photosynthesis. Part of this process includes the replacement of six photosystem I (PSI) subunits with isoforms that confer the binding of chlorophyll (Chl) f molecules that absorb far-red light (FRL). However, the exact sites at which Chl f molecules are bound are still challenging to determine. To aid in the identification of Chl f-binding sites, we solved the cryo-EM structure of PSI from far-red light-acclimated cells of the cyanobacterium Synechococcus sp. PCC 7335. We identified six sites that bind Chl f with high specificity and three additional sites that are likely to bind Chl f at lower specificity. All of these binding sites are in the core-antenna regions of PSI, and Chl f was not observed among the electron transfer cofactors. This structural analysis also reveals both conserved and nonconserved Chl f-binding sites, the latter of which exemplify the diversity in FRL-PSI among species. We found that the FRL-PSI structure also contains a bound soluble ferredoxin, PetF1, at low occupancy, which suggests that ferredoxin binds less transiently than expected according to the canonical view of ferredoxin-binding to facilitate electron transfer. We suggest that this may result from structural changes in FRL-PSI that occur specifically during FRL photoacclimation.
Collapse
Affiliation(s)
| | - David A Flesher
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA
| | - Gaozhong Shen
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Jimin Wang
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA
| | - Ming-Yang Ho
- Department of Life Science, National Taiwan University, Taipei, Taiwan
| | - Gary W Brudvig
- Department of Chemistry, Yale University, New Haven, Connecticut, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA.
| | - Donald A Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA.
| |
Collapse
|
8
|
Ríos-Meléndez S, Valadez-Hernández E, Delgadillo C, Luna-Guevara ML, Martínez-Núñez MA, Sánchez-Pérez M, Martínez-Y-Pérez JL, Arroyo-Becerra A, Cárdenas L, Bibbins-Martínez M, Maldonado-Mendoza IE, Villalobos-López MA. Pseudocrossidium replicatum (Taylor) R.H. Zander is a fully desiccation-tolerant moss that expresses an inducible molecular mechanism in response to severe abiotic stress. PLANT MOLECULAR BIOLOGY 2021; 107:387-404. [PMID: 34189708 PMCID: PMC8648698 DOI: 10.1007/s11103-021-01167-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 06/10/2021] [Indexed: 05/04/2023]
Abstract
KEY MESSAGE The moss Pseudocrossidium replicatum is a desiccation-tolerant species that uses an inducible system to withstand severe abiotic stress in both protonemal and gametophore tissues. Desiccation tolerance (DT) is the ability of cells to recover from an air-dried state. Here, the moss Pseudocrossidium replicatum was identified as a fully desiccation-tolerant (FDT) species. Its gametophores rapidly lost more than 90% of their water content when exposed to a low-humidity atmosphere [23% relative humidity (RH)], but abscisic acid (ABA) pretreatment diminished the final water loss after equilibrium was reached. P. replicatum gametophores maintained good maximum photosystem II (PSII) efficiency (Fv/Fm) for up to two hours during slow dehydration; however, ABA pretreatment induced a faster decrease in the Fv/Fm. ABA also induced a faster recovery of the Fv/Fm after rehydration. Protein synthesis inhibitor treatment before dehydration hampered the recovery of the Fv/Fm when the gametophores were rehydrated after desiccation, suggesting the presence of an inducible protective mechanism that is activated in response to abiotic stress. This observation was also supported by accumulation of soluble sugars in gametophores exposed to ABA or NaCl. Exogenous ABA treatment delayed the germination of P. replicatum spores and induced morphological changes in protonemal cells that resembled brachycytes. Transcriptome analyses revealed the presence of an inducible molecular mechanism in P. replicatum protonemata that was activated in response to dehydration. This study is the first RNA-Seq study of the protonemal tissues of an FDT moss. Our results suggest that P. replicatum is an FDT moss equipped with an inducible molecular response that prepares this species for severe abiotic stress and that ABA plays an important role in this response.
Collapse
Affiliation(s)
- Selma Ríos-Meléndez
- Laboratorio de Genómica Funcional y Biotecnología de Plantas, Centro de Investigación en Biotecnología Aplicada, Instituto Politécnico Nacional, C.P. 90700, Tepetitla de Lardizábal, Tlaxcala, México
| | - Emmanuel Valadez-Hernández
- Laboratorio de Genómica Funcional y Biotecnología de Plantas, Centro de Investigación en Biotecnología Aplicada, Instituto Politécnico Nacional, C.P. 90700, Tepetitla de Lardizábal, Tlaxcala, México
| | - Claudio Delgadillo
- Instituto de Biología, Universidad Nacional Autónoma de México, Ciudad de México, México
| | - Maria L Luna-Guevara
- Facultad de Ingeniería Química, Benemérita Universidad Autónoma de Puebla, C.P. 72000, Puebla, Puebla, México
| | - Mario A Martínez-Núñez
- UMDI-Sisal, Facultad de Ciencias, Universidad Nacional Autónoma de México, C.P. 97302, Mérida, Yucatán, México
| | - Mishael Sánchez-Pérez
- Unidad de Análisis Bioinformáticos, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, C.P. 62210, Cuernavaca, Morelos, México
| | - José L Martínez-Y-Pérez
- Centro de Investigación en Genética y Ambiente, Universidad Autónoma de Tlaxcala, C.P. 90210, Ixtacuixtla, Tlaxcala, México
| | - Analilia Arroyo-Becerra
- Laboratorio de Genómica Funcional y Biotecnología de Plantas, Centro de Investigación en Biotecnología Aplicada, Instituto Politécnico Nacional, C.P. 90700, Tepetitla de Lardizábal, Tlaxcala, México
| | - Luis Cárdenas
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, C.P. 62210, Cuernavaca, Morelos, México
| | - Martha Bibbins-Martínez
- Laboratorio de Genómica Funcional y Biotecnología de Plantas, Centro de Investigación en Biotecnología Aplicada, Instituto Politécnico Nacional, C.P. 90700, Tepetitla de Lardizábal, Tlaxcala, México
| | - Ignacio E Maldonado-Mendoza
- Centro Interdisciplinario de Investigación para el Desarrollo Integral Regional, Unidad Sinaloa, Instituto Politécnico Nacional, C.P. 81049, Guasave, Sinaloa, México
| | - Miguel Angel Villalobos-López
- Laboratorio de Genómica Funcional y Biotecnología de Plantas, Centro de Investigación en Biotecnología Aplicada, Instituto Politécnico Nacional, C.P. 90700, Tepetitla de Lardizábal, Tlaxcala, México.
| |
Collapse
|
9
|
Meng X, Wang X, Zhang Z, Xiong S, Wei Y, Guo J, Zhang J, Wang L, Ma X, Tegeder M. Transcriptomic, proteomic, and physiological studies reveal key players in wheat nitrogen use efficiency under both high and low nitrogen supply. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:4435-4456. [PMID: 33829261 DOI: 10.1093/jxb/erab153] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 04/02/2021] [Indexed: 06/12/2023]
Abstract
The effective use of available nitrogen (N) to improve crop grain yields provides an important strategy to reduce environmental N pollution and promote sustainable agriculture. However, little is known about the common genetic basis of N use efficiency (NUE) at varying N availability. Two wheat (Triticum aestivum L.) cultivars were grown in the field with high, moderate, and low N supply. Cultivar Zhoumai 27 outperformed Aikang 58 independent of the N supply and showed improved growth, canopy leaf area index, flag leaf surface area, grain number, and yield, and enhanced NUE due to both higher N uptake and utilization efficiency. Further, transcriptome and proteome analyses were performed using flag leaves that provide assimilates for grain growth. The results showed that many genes or proteins that are up- or down-regulated under all N regimes are associated with N and carbon metabolism and transport. This was reinforced by cultivar differences in photosynthesis, assimilate phloem transport, and grain protein/starch yield. Overall, our study establishes that improving NUE at both high and low N supply requires distinct adjustments in leaf metabolism and assimilate partitioning. Identified key genes/proteins may individually or concurrently regulate NUE and are promising targets for maximizing crop NUE irrespective of the N supply.
Collapse
Affiliation(s)
- Xiaodan Meng
- Collaborative Innovation Center of Henan Grain Crops, Henan Agricultural University, ZhengzhouChina
- College of Agronomy, Henan Agricultural University, ZhengzhouChina
- School of Biological Sciences, Washington State University, Pullman, WAUSA
| | - Xiaochun Wang
- Collaborative Innovation Center of Henan Grain Crops, Henan Agricultural University, ZhengzhouChina
| | - Zhiyong Zhang
- Collaborative Innovation Center of Henan Grain Crops, Henan Agricultural University, ZhengzhouChina
- College of Agronomy, Henan Agricultural University, ZhengzhouChina
| | - Shuping Xiong
- Collaborative Innovation Center of Henan Grain Crops, Henan Agricultural University, ZhengzhouChina
- College of Agronomy, Henan Agricultural University, ZhengzhouChina
| | - Yihao Wei
- Collaborative Innovation Center of Henan Grain Crops, Henan Agricultural University, ZhengzhouChina
- College of Agronomy, Henan Agricultural University, ZhengzhouChina
| | - Jianbiao Guo
- College of Agronomy, Henan Agricultural University, ZhengzhouChina
| | - Jie Zhang
- College of Agronomy, Henan Agricultural University, ZhengzhouChina
| | - Lulu Wang
- College of Agronomy, Henan Agricultural University, ZhengzhouChina
| | - Xinming Ma
- Collaborative Innovation Center of Henan Grain Crops, Henan Agricultural University, ZhengzhouChina
- College of Agronomy, Henan Agricultural University, ZhengzhouChina
| | - Mechthild Tegeder
- School of Biological Sciences, Washington State University, Pullman, WAUSA
| |
Collapse
|
10
|
Landi M, Agati G, Fini A, Guidi L, Sebastiani F, Tattini M. Unveiling the shade nature of cyanic leaves: A view from the "blue absorbing side" of anthocyanins. PLANT, CELL & ENVIRONMENT 2021; 44:1119-1129. [PMID: 32515010 DOI: 10.1111/pce.13818] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 06/01/2020] [Indexed: 05/02/2023]
Abstract
Anthocyanins have long been suggested as having great potential in offering photoprotection to plants facing high light irradiance. Nonetheless, their effective ability in protecting the photosynthetic apparatus from supernumerary photons has been questioned by some authors, based upon the inexact belief that anthocyanins almost exclusively absorb green photons, which are poorly absorbed by chlorophylls. Here we focus on the blue light absorbing features of anthocyanins, a neglected issue in anthocyanin research. Anthocyanins effectively absorb blue photons: the absorbance of blue relative to green photons increases from tri- to mono-hydroxy B-ring substituted structures, reaching up to 50% of green photons absorption. We offer a comprehensive picture of the molecular events activated by low blue-light availability, extending our previous analysis in purple and green basil, which we suggest to be responsible for the "shade syndrome" displayed by cyanic leaves. While purple leaves display overexpression of genes promoting chlorophyll biosynthesis and light harvesting, in green leaves it is the genes involved in the stability/repair of photosystems that are largely overexpressed. As a corollary, this adds further support to the view of an effective photoprotective role of anthocyanins. We discuss the profound morpho-anatomical adjustments imposed by the epidermal anthocyanin shield, which reflect adjustments in light harvesting capacity under imposed shade and make complex the analysis of the photosynthetic performance of cyanic versus acyanic leaves.
Collapse
Affiliation(s)
- Marco Landi
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
| | - Giovanni Agati
- Institute of Applied Physics 'Nello Carrara', Florence, Italy
| | - Alessio Fini
- Department of Agricultural and Environmental Sciences-Production, Landscape, Agroenergy University of Milan, Milan, Italy
| | - Lucia Guidi
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
| | - Federico Sebastiani
- Institute for Sustainable Plant Protection, National Research Council of Italy, Florence, Italy
| | - Massimiliano Tattini
- Institute for Sustainable Plant Protection, National Research Council of Italy, Florence, Italy
| |
Collapse
|
11
|
Skalák J, Vercruyssen L, Claeys H, Hradilová J, Černý M, Novák O, Plačková L, Saiz-Fernández I, Skaláková P, Coppens F, Dhondt S, Koukalová Š, Zouhar J, Inzé D, Brzobohatý B. Multifaceted activity of cytokinin in leaf development shapes its size and structure in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2019; 97:805-824. [PMID: 30748050 DOI: 10.1111/tpj.14285] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 01/05/2019] [Accepted: 01/10/2019] [Indexed: 05/20/2023]
Abstract
The phytohormone cytokinin has been shown to affect many aspects of plant development ranging from the regulation of the shoot apical meristem to leaf senescence. However, some studies have reported contradictory effects of cytokinin on leaf physiology. Therefore cytokinin treatments cause both chlorosis and increased greening and both lead to decrease or increase in cell size. To elucidate this multifaceted role of cytokinin in leaf development, we have employed a system of temporal controls over the cytokinin pool and investigated the consequences of modulated cytokinin levels in the third leaf of Arabidopsis. We show that, at the cell proliferation phase, cytokinin is needed to maintain cell proliferation by blocking the transition to cell expansion and the onset of photosynthesis. Transcriptome profiling revealed regulation by cytokinin of a gene suite previously shown to affect cell proliferation and expansion and thereby a molecular mechanism by which cytokinin modulates a molecular network underlying the cellular responses. During the cell expansion phase, cytokinin stimulates cell expansion and differentiation. Consequently, a cytokinin excess at the cell expansion phase results in an increased leaf and rosette size fueled by higher cell expansion rate, yielding higher shoot biomass. Proteome profiling revealed the stimulation of primary metabolism by cytokinin, in line with an increased sugar content that is expected to increase turgor pressure, representing the driving force of cell expansion. Therefore, the developmental timing of cytokinin content fluctuations, together with a tight control of primary metabolism, is a key factor mediating transitions from cell proliferation to cell expansion in leaves.
Collapse
Affiliation(s)
- Jan Skalák
- Department of Molecular Biology and Radiobiology, Faculty of AgriSciences, Mendel University in Brno, Zemědělská 1, CZ-61300, Brno, Czech Republic
| | - Liesbeth Vercruyssen
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052, Ghent, Belgium
- VIB Center for Plant Systems Biology, 9052, Ghent, Belgium
| | - Hannes Claeys
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052, Ghent, Belgium
- VIB Center for Plant Systems Biology, 9052, Ghent, Belgium
| | - Jana Hradilová
- Department of Molecular Biology and Radiobiology, Faculty of AgriSciences, Mendel University in Brno, Zemědělská 1, CZ-61300, Brno, Czech Republic
| | - Martin Černý
- Department of Molecular Biology and Radiobiology, Faculty of AgriSciences, Mendel University in Brno, Zemědělská 1, CZ-61300, Brno, Czech Republic
| | - Ondřej Novák
- Laboratory of Growth Regulators, The Czech Academy of Sciences, Institute of Experimental Botany & Palacký University, Šlechtitelů 27, CZ-78371, Olomouc, Czech Republic
| | - Lenka Plačková
- Laboratory of Growth Regulators, The Czech Academy of Sciences, Institute of Experimental Botany & Palacký University, Šlechtitelů 27, CZ-78371, Olomouc, Czech Republic
| | - Iñigo Saiz-Fernández
- Department of Molecular Biology and Radiobiology, Faculty of AgriSciences, Mendel University in Brno, Zemědělská 1, CZ-61300, Brno, Czech Republic
| | - Patricie Skaláková
- Department of Molecular Biology and Radiobiology, Faculty of AgriSciences, Mendel University in Brno, Zemědělská 1, CZ-61300, Brno, Czech Republic
| | - Frederik Coppens
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052, Ghent, Belgium
- VIB Center for Plant Systems Biology, 9052, Ghent, Belgium
| | - Stijn Dhondt
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052, Ghent, Belgium
- VIB Center for Plant Systems Biology, 9052, Ghent, Belgium
| | - Šárka Koukalová
- Department of Molecular Biology and Radiobiology, Faculty of AgriSciences, Mendel University in Brno, Zemědělská 1, CZ-61300, Brno, Czech Republic
- CEITEC - Central European Institute of Technology, Mendel University in Brno, Zemědělská 1, CZ-61300, Brno, Czech Republic
| | - Jan Zouhar
- Department of Molecular Biology and Radiobiology, Faculty of AgriSciences, Mendel University in Brno, Zemědělská 1, CZ-61300, Brno, Czech Republic
- CEITEC - Central European Institute of Technology, Mendel University in Brno, Zemědělská 1, CZ-61300, Brno, Czech Republic
| | - Dirk Inzé
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052, Ghent, Belgium
- VIB Center for Plant Systems Biology, 9052, Ghent, Belgium
| | - Břetislav Brzobohatý
- Department of Molecular Biology and Radiobiology, Faculty of AgriSciences, Mendel University in Brno, Zemědělská 1, CZ-61300, Brno, Czech Republic
- CEITEC - Central European Institute of Technology, Mendel University in Brno, Zemědělská 1, CZ-61300, Brno, Czech Republic
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, CZ-61265, Brno, Czech Republic
| |
Collapse
|
12
|
Xie D, Shi J, Zhang A, Lei Z, Zu G, Fu Y, Gan X, Yin L, Song B, Hu D. Syntheses, antiviral activities and induced resistance mechanisms of novel quinazoline derivatives containing a dithioacetal moiety. Bioorg Chem 2018; 80:433-443. [PMID: 29986188 DOI: 10.1016/j.bioorg.2018.06.026] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 06/09/2018] [Accepted: 06/20/2018] [Indexed: 11/26/2022]
Abstract
A series of novel quinazoline derivatives containing a dithioacetal moiety were designed and synthesized, and their structures were characterized by 1H nuclear magnetic resonance, 13C nuclear magnetic resonance, and high-resolution mass spectrometry. Bioassay results indicated that compound 4b exhibited remarkable protective activity against cucumber mosaic virus (CMV, EC50 = 248.6 μg/mL) and curative activity against potato virus Y (EC50 = 350.5 μg/mL), which were better than those of ningnanmycin (357.7 μg/mL and 493.7 μg/mL, respectively). Moreover, compound 4b could increase the chlorophyll content in plants, improve photosynthesis, and effectively induce tobacco anti-CMV activity.
Collapse
Affiliation(s)
- Dandan Xie
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Jing Shi
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Awei Zhang
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Zhiwei Lei
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Guangcheng Zu
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Yun Fu
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Xiuhai Gan
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Limin Yin
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Baoan Song
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China.
| | - Deyu Hu
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China.
| |
Collapse
|
13
|
Pan X, Ma J, Su X, Cao P, Chang W, Liu Z, Zhang X, Li M. Structure of the maize photosystem I supercomplex with light-harvesting complexes I and II. Science 2018; 360:1109-1113. [PMID: 29880686 DOI: 10.1126/science.aat1156] [Citation(s) in RCA: 115] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Accepted: 04/16/2018] [Indexed: 01/15/2023]
Abstract
Plants regulate photosynthetic light harvesting to maintain balanced energy flux into photosystems I and II (PSI and PSII). Under light conditions favoring PSII excitation, the PSII antenna, light-harvesting complex II (LHCII), is phosphorylated and forms a supercomplex with PSI core and the PSI antenna, light-harvesting complex I (LHCI). Both LHCI and LHCII then transfer excitation energy to the PSI core. We report the structure of maize PSI-LHCI-LHCII solved by cryo-electron microscopy, revealing the recognition site between LHCII and PSI. The PSI subunits PsaN and PsaO are observed at the PSI-LHCI interface and the PSI-LHCII interface, respectively. Each subunit relays excitation to PSI core through a pair of chlorophyll molecules, thus revealing previously unseen paths for energy transfer between the antennas and the PSI core.
Collapse
Affiliation(s)
- Xiaowei Pan
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, P.R. China
| | - Jun Ma
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, P.R. China
| | - Xiaodong Su
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, P.R. China
| | - Peng Cao
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, P.R. China
| | - Wenrui Chang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, P.R. China.,University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Zhenfeng Liu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, P.R. China.,University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Xinzheng Zhang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, P.R. China. .,University of Chinese Academy of Sciences, Beijing 100049, P.R. China.,Center for Biological Imaging, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, P.R. China
| | - Mei Li
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, P.R. China.
| |
Collapse
|
14
|
Marco P, Kozuleva M, Eilenberg H, Mazor Y, Gimeson P, Kanygin A, Redding K, Weiner I, Yacoby I. Binding of ferredoxin to algal photosystem I involves a single binding site and is composed of two thermodynamically distinct events. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2018; 1859:234-243. [DOI: 10.1016/j.bbabio.2018.01.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Revised: 01/07/2018] [Accepted: 01/08/2018] [Indexed: 10/18/2022]
|
15
|
Ramamoorthy R, Vishal B, Ramachandran S, Kumar PP. The OsPS1-F gene regulates growth and development in rice by modulating photosynthetic electron transport rate. PLANT CELL REPORTS 2018; 37:377-385. [PMID: 29149369 DOI: 10.1007/s00299-017-2235-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 11/08/2017] [Indexed: 05/24/2023]
Abstract
Ds insertion in rice OsPS1-F gene results in semi-dwarf plants with reduced tiller number and grain yield, while genetic complementation with OsPS1-F rescued the mutant phenotype. Photosynthetic electron transport is regulated in the chloroplast thylakoid membrane by multi-protein complexes. Studies about photosynthetic machinery and its subunits in crop plants are necessary, because they could be crucial for yield enhancement in the long term. Here, we report the characterization of OsPS1-F (encoding Oryza sativa PHOTOSYSTEM 1-F subunit) using a single copy Ds insertion rice mutant line. The homozygous mutant (osps1-f) showed striking difference in growth and development compared to the wild type (WT), including, reduction in plant height, tiller number, grain yield as well as pale yellow leaf coloration. Chlorophyll concentration and electron transport rate were significantly reduced in the mutant compared to the WT. OsPS1-F gene was highly expressed in rice leaves compared to other tissues at different developmental stages tested. Upon complementation of the mutant with proUBI::OsPS1-F, the observed mutant phenotypes were rescued. Our results illustrate that OsPS1-F plays an important role in regulating proper growth and development of rice plants.
Collapse
Affiliation(s)
- Rengasamy Ramamoorthy
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, 117543, Republic of Singapore
| | - Bhushan Vishal
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, 117543, Republic of Singapore
| | - Srinivasan Ramachandran
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, 117604, Republic of Singapore
| | - Prakash P Kumar
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, 117543, Republic of Singapore.
| |
Collapse
|
16
|
Extensive gain and loss of photosystem I subunits in chromerid algae, photosynthetic relatives of apicomplexans. Sci Rep 2017; 7:13214. [PMID: 29038514 PMCID: PMC5643376 DOI: 10.1038/s41598-017-13575-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 09/26/2017] [Indexed: 12/16/2022] Open
Abstract
In oxygenic photosynthesis the initial photochemical processes are carried out by photosystem I (PSI) and II (PSII). Although subunit composition varies between cyanobacterial and plastid photosystems, the core structures of PSI and PSII are conserved throughout photosynthetic eukaryotes. So far, the photosynthetic complexes have been characterised in only a small number of organisms. We performed in silico and biochemical studies to explore the organization and evolution of the photosynthetic apparatus in the chromerids Chromera velia and Vitrella brassicaformis, autotrophic relatives of apicomplexans. We catalogued the presence and location of genes coding for conserved subunits of the photosystems as well as cytochrome b6f and ATP synthase in chromerids and other phototrophs and performed a phylogenetic analysis. We then characterised the photosynthetic complexes of Chromera and Vitrella using 2D gels combined with mass-spectrometry and further analysed the purified Chromera PSI. Our data suggest that the photosynthetic apparatus of chromerids underwent unique structural changes. Both photosystems (as well as cytochrome b6f and ATP synthase) lost several canonical subunits, while PSI gained one superoxide dismutase (Vitrella) or two superoxide dismutases and several unknown proteins (Chromera) as new regular subunits. We discuss these results in light of the extraordinarily efficient photosynthetic processes described in Chromera.
Collapse
|
17
|
Wittenberg G, Järvi S, Hojka M, Tóth SZ, Meyer EH, Aro EM, Schöttler MA, Bock R. Identification and characterization of a stable intermediate in photosystem I assembly in tobacco. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2017; 90:478-490. [PMID: 28161893 DOI: 10.1111/tpj.13505] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 01/29/2017] [Accepted: 01/31/2017] [Indexed: 05/06/2023]
Abstract
Photosystem I (PSI) is the most efficient bioenergetic nanomachine in nature and one of the largest membrane protein complexes known. It is composed of 18 protein subunits that bind more than 200 co-factors and prosthetic groups. While the structure and function of PSI have been studied in great detail, very little is known about the PSI assembly process. In this work, we have characterized a PSI assembly intermediate in tobacco plants, which we named PSI*. We found PSI* to contain only a specific subset of the core subunits of PSI. PSI* is particularly abundant in young leaves where active thylakoid biogenesis takes place. Moreover, PSI* was found to overaccumulate in PsaF-deficient mutant plants, and we show that re-initiation of PsaF synthesis promotes the maturation of PSI* into PSI. The attachment of antenna proteins to PSI also requires the transition from PSI* to mature PSI. Our data could provide a biochemical entry point into the challenging investigation of PSI biogenesis and allow us to improve the model for the assembly pathway of PSI in thylakoid membranes of vascular plants.
Collapse
Affiliation(s)
- Gal Wittenberg
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476, Potsdam-Golm, Germany
| | - Sari Järvi
- Department of Biochemistry, Molecular Plant Biology, University of Turku, FI-20014, Turku, Finland
| | - Marta Hojka
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476, Potsdam-Golm, Germany
| | - Szilvia Z Tóth
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476, Potsdam-Golm, Germany
| | - Etienne H Meyer
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476, Potsdam-Golm, Germany
| | - Eva-Mari Aro
- Department of Biochemistry, Molecular Plant Biology, University of Turku, FI-20014, Turku, Finland
| | - Mark A Schöttler
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476, Potsdam-Golm, Germany
| | - Ralph Bock
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476, Potsdam-Golm, Germany
| |
Collapse
|
18
|
Schöttler MA, Thiele W, Belkius K, Bergner SV, Flügel C, Wittenberg G, Agrawal S, Stegemann S, Ruf S, Bock R. The plastid-encoded PsaI subunit stabilizes photosystem I during leaf senescence in tobacco. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:1137-1155. [PMID: 28180288 PMCID: PMC5429015 DOI: 10.1093/jxb/erx009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
PsaI is the only subunit of PSI whose precise physiological function has not yet been elucidated in higher plants. While PsaI is involved in PSI trimerization in cyanobacteria, trimerization was lost during the evolution of the eukaryotic PSI, and the entire PsaI side of PSI underwent major structural remodelling to allow for binding of light harvesting complex II antenna proteins during state transitions. Here, we have generated a tobacco (Nicotiana tabacum) knockout mutant of the plastid-encoded psaI gene. We show that PsaI is not required for the redox reactions of PSI. Neither plastocyanin oxidation nor the processes at the PSI acceptor side are impaired in the mutant, and both linear and cyclic electron flux rates are unaltered. The PSI antenna cross section is unaffected, state transitions function normally, and binding of other PSI subunits to the reaction centre is not compromised. Under a wide range of growth conditions, the mutants are phenotypically and physiologically indistinguishable from wild-type tobacco. However, in response to high-light and chilling stress, and especially during leaf senescence, PSI content is reduced in the mutants, indicating that the I-subunit plays a role in stabilizing PSI complexes.
Collapse
Affiliation(s)
- Mark Aurel Schöttler
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany
| | - Wolfram Thiele
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany
| | - Karolina Belkius
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany
| | - Sonja Verena Bergner
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany
| | - Claudia Flügel
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany
| | - Gal Wittenberg
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany
| | - Shreya Agrawal
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany
| | - Sandra Stegemann
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany
| | - Stephanie Ruf
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany
| | - Ralph Bock
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany
| |
Collapse
|
19
|
Validation of reference genes for cryopreservation studies with the gorgonian coral endosymbiont Symbiodinium. Sci Rep 2017; 7:39396. [PMID: 28067273 PMCID: PMC5220285 DOI: 10.1038/srep39396] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 11/23/2016] [Indexed: 12/18/2022] Open
Abstract
Quantification by real-time RT-PCR requires a stable internal reference known as a housekeeping gene (HKG) for normalising the mRNA levels of target genes. The present study identified and validated stably expressed HKGs in post-thaw Symbiodinium clade G. Six potential HKGs, namely, pcna, gapdh, 18S rRNA, hsp90, rbcl, and ps1, were analysed using three different algorithms, namely, GeNorm, NormFinder, and BestKeeper. The GeNorm algorithm ranked the candidate genes as follows in the order of decreasing stability: pcna and gapdh > ps1 > 18S rRNA > hsp90 > rbcl. Results obtained using the NormFinder algorithm also showed that pcna was the most stable HKG and ps1 was the second most stable HKG. We found that the candidate HKGs examined in this study showed variable stability with respect to the three algorithms. These results indicated that both pcna and ps1 were suitable for normalising target gene expression determined by performing real-time RT-PCR in cryopreservation studies on Symbiodinium clade G. The results of the present study would help future studies to elucidate the effect of cryopreservation on gene expression in dinoflagellates.
Collapse
|
20
|
Wang L, Li Q, Zhang A, Zhou W, Jiang R, Yang Z, Yang H, Qin X, Ding S, Lu Q, Wen X, Lu C. The Phytol Phosphorylation Pathway Is Essential for the Biosynthesis of Phylloquinone, which Is Required for Photosystem I Stability in Arabidopsis. MOLECULAR PLANT 2017; 10:183-196. [PMID: 28007557 DOI: 10.1016/j.molp.2016.12.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2016] [Revised: 12/03/2016] [Accepted: 12/12/2016] [Indexed: 05/16/2023]
Abstract
Phytyl-diphosphate, which provides phytyl moieties as a common substrate in both tocopherol and phylloquinone biosynthesis, derives from de novo isoprenoid biosynthesis or a salvage pathway via phytol phosphorylation. However, very little is known about the role and origin of the phytyl moiety for phylloquinone biosynthesis. Since VTE6, a phytyl-phosphate kinase, is a key enzyme for phytol phosphorylation, we characterized Arabidopsis vte6 mutants to gain insight into the roles of phytyl moieties in phylloquinone biosynthesis and of phylloquinone in photosystem I (PSI) biogenesis. The VTE6 knockout mutants vte6-1 and vte6-2 lacked detectable phylloquinone, whereas the phylloquinone content in the VTE6 knockdown mutant vte6-3 was 90% lower than that in wild-type. In vte6 mutants, PSI function was impaired and accumulation of the PSI complex was defective. The PSI core subunits PsaA/B were efficiently synthesized and assembled into the PSI complex in vte6-3. However, the degradation rate of PSI subunits in the assembled PSI complex was more rapid in vte6-3 than in wild-type. In vte6-3, PSI was more susceptible to high-light damage than in wild-type. Our results provide the first genetic evidence that the phytol phosphorylation pathway is essential for phylloquinone biosynthesis, and that phylloquinone is required for PSI complex stability.
Collapse
Affiliation(s)
- Lei Wang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qingwei Li
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Aihong Zhang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Wen Zhou
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Rui Jiang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhipan Yang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Huixia Yang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Xiaochun Qin
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Shunhua Ding
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Qingtao Lu
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Xiaogang Wen
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Congming Lu
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; National Center for Plant Gene Research, Beijing 100093, China.
| |
Collapse
|
21
|
Yousuf PY, Ahmad A, Aref IM, Ozturk M, Ganie AH, Iqbal M. Salt-stress-responsive chloroplast proteins in Brassica juncea genotypes with contrasting salt tolerance and their quantitative PCR analysis. PROTOPLASMA 2016; 253:1565-1575. [PMID: 26638208 DOI: 10.1007/s00709-015-0917-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2015] [Accepted: 11/23/2015] [Indexed: 05/21/2023]
Abstract
Brassica juncea is mainly cultivated in the arid and semi-arid regions of India where its production is significantly affected by soil salinity. Adequate knowledge of the mechanisms underlying the salt tolerance at sub-cellular levels must aid in developing the salt-tolerant plants. A proper functioning of chloroplasts under salinity conditions is highly desirable to maintain crop productivity. The adaptive molecular mechanisms offered by plants at the chloroplast level to cope with salinity stress must be a prime target in developing the salt-tolerant plants. In the present study, we have analyzed differential expression of chloroplast proteins in two Brassica juncea genotypes, Pusa Agrani (salt-sensitive) and CS-54 (salt-tolerant), under the effect of sodium chloride. The chloroplast proteins were isolated and resolved using 2DE, which facilitated identification and quantification of 12 proteins that differed in expression in the salt-tolerant and salt-sensitive genotypes. The identified proteins were related to a variety of chloroplast-associated molecular processes, including oxygen-evolving process, PS I and PS II functioning, Calvin cycle and redox homeostasis. Expression analysis of genes encoding differentially expressed proteins through real time PCR supported our findings with proteomic analysis. The study indicates that modulating the expression of chloroplast proteins associated with stabilization of photosystems and oxidative defence plays imperative roles in adaptation to salt stress.
Collapse
Affiliation(s)
- Peerzada Yasir Yousuf
- Department of Botany, Molecular Ecology Laboratory, Jamia Hamdard, New Delhi, 110062, India
| | - Altaf Ahmad
- Department of Botany, Aligarh Muslim University, Aligarh, 202002, India
| | - Ibrahim M Aref
- Department of Plant Production, College of Food and Agricultural Science, King Saud University, Post Box 2460, Riyadh, 11451, Saudi Arabia
| | - Munir Ozturk
- Department of Biology, Ege University, Izmir, 350000, Turkey
| | - Arshid Hussain Ganie
- Department of Botany, Molecular Ecology Laboratory, Jamia Hamdard, New Delhi, 110062, India
| | - Muhammad Iqbal
- Department of Botany, Molecular Ecology Laboratory, Jamia Hamdard, New Delhi, 110062, India.
| |
Collapse
|
22
|
Chakrabarti M, Dinkins RD, Hunt AG. De novo Transcriptome Assembly and Dynamic Spatial Gene Expression Analysis in Red Clover. THE PLANT GENOME 2016; 9. [PMID: 27898811 DOI: 10.3835/plantgenome2015.06.0048] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Red clover ( L.) is a cool-season forage legume grown throughout the northeastern United States and is the most widely planted forage legume after alfalfa ( L.). Red clover provides high-value feed to the livestock because of high protein content and easy digestibility. To date, genomic resources for red clover are scarce. In the current study, a de novo transcriptome assembly of red clover was constructed representing different tissue types. The draft assembly consists of 37,565 contigs with N50 and average contig length of 1707 and 1262 bp, respectively. A comparative study with three other legume species displayed a high degree of sequence conservation between red clover and other legumes. The assembled transcriptome was annotated to allow identification of desirable genes. In particular, a genome-wide identification of red clover transcripts encoding putative transcription factors was performed. A comparative gene expression analysis between different tissue types was performed using the assembled transcriptome as the reference, which revealed dynamic gene expression patterns across different tissue types and also identified spatially dynamic gene coexpression clusters. Genes representing tissue-enriched clusters were subjected to gene ontology (GO) enrichment analysis to identify over-represented functional groups. Identification of these tissue-enriched gene coexpression clusters can help in future research focusing on developmental studies across tissues or in biotechnological improvement of red clover.
Collapse
|
23
|
Yang H, Liu J, Wen X, Lu C. Molecular mechanism of photosystem I assembly in oxygenic organisms. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1847:838-48. [PMID: 25582571 DOI: 10.1016/j.bbabio.2014.12.011] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 12/27/2014] [Accepted: 12/30/2014] [Indexed: 11/26/2022]
Abstract
Photosystem I, an integral membrane and multi-subunit complex, catalyzes the oxidation of plastocyanin and the reduction of ferredoxin by absorbed light energy. Photosystem I participates in photosynthetic acclimation processes by being involved in cyclic electron transfer and state transitions for sustaining efficient photosynthesis. The photosystem I complex is highly conserved from cyanobacteria to higher plants and contains the light-harvesting complex and the reaction center complex. The assembly of the photosystem I complex is highly complicated and involves the concerted assembly of multiple subunits and hundreds of cofactors. A suite of regulatory factors for the assembly of photosystem I subunits and cofactors have been identified that constitute an integrative network regulating PSI accumulation. This review aims to discuss recent findings in the field relating to how the photosystem I complex is assembled in oxygenic organisms. This article is part of a Special Issue entitled: Chloroplast Biogenesis.
Collapse
Affiliation(s)
- Huixia Yang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Jun Liu
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
| | - Xiaogang Wen
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Congming Lu
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
| |
Collapse
|
24
|
Roose JL, Frankel LK, Bricker TM. The PsbP domain protein 1 functions in the assembly of lumenal domains in photosystem I. J Biol Chem 2014; 289:23776-85. [PMID: 25008325 DOI: 10.1074/jbc.m114.589085] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Photosystem I (PS I) is a multisubunit membrane protein complex that functions as a light-driven plastocyanin-ferredoxin oxidoreductase. The PsbP domain protein 1 (PPD1; At4g15510) is located in the thylakoid lumen of plant chloroplasts and is essential for photoautotrophy, functioning as a PS I assembly factor. In this work, RNAi was used to suppress PPD1 expression, yielding mutants displaying a range of phenotypes with respect to PS I accumulation and function. These PPD1 RNAi mutants showed a loss of assembled PS I that was correlated with loss of the PPD1 protein. In the most severely affected PPD1 RNAi lines, the accumulated PS I complexes exhibited defects in electron transfer from plastocyanin to the oxidized reaction center P700 (+). The defects in PS I assembly in the PPD1 RNAi mutants also had secondary effects with respect to the association of light-harvesting antenna complexes to PS I. Because of the imbalance in photosystem function in the PPD1 RNAi mutants, light-harvesting complex II associated with and acted as an antenna for the PS I complexes. These results provide new evidence for the role of PPD1 in PS I biogenesis, particularly as a factor essential for proper assembly of the lumenal portion of the complex.
Collapse
Affiliation(s)
- Johnna L Roose
- From the Department of Biological Sciences, Biochemistry and Molecular Biology Section, Louisiana State University, Baton Rouge, Louisiana 70803
| | - Laurie K Frankel
- From the Department of Biological Sciences, Biochemistry and Molecular Biology Section, Louisiana State University, Baton Rouge, Louisiana 70803
| | - Terry M Bricker
- From the Department of Biological Sciences, Biochemistry and Molecular Biology Section, Louisiana State University, Baton Rouge, Louisiana 70803
| |
Collapse
|
25
|
Pribil M, Labs M, Leister D. Structure and dynamics of thylakoids in land plants. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:1955-72. [PMID: 24622954 DOI: 10.1093/jxb/eru090] [Citation(s) in RCA: 173] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Thylakoids of land plants have a bipartite structure, consisting of cylindrical grana stacks, made of membranous discs piled one on top of the other, and stroma lamellae which are helically wound around the cylinders. Protein complexes predominantly located in the stroma lamellae and grana end membranes are either bulky [photosystem I (PSI) and the chloroplast ATP synthase (cpATPase)] or are involved in cyclic electron flow [the NAD(P)H dehydrogenase (NDH) and PGRL1-PGR5 heterodimers], whereas photosystem II (PSII) and its light-harvesting complex (LHCII) are found in the appressed membranes of the granum. Stacking of grana is thought to be due to adhesion between Lhcb proteins (LHCII or CP26) located in opposed thylakoid membranes. The grana margins contain oligomers of CURT1 proteins, which appear to control the size and number of grana discs in a dosage- and phosphorylation-dependent manner. Depending on light conditions, thylakoid membranes undergo dynamic structural changes that involve alterations in granum diameter and height, vertical unstacking of grana, and swelling of the thylakoid lumen. This plasticity is realized predominantly by reorganization of the supramolecular structure of protein complexes within grana stacks and by changes in multiprotein complex composition between appressed and non-appressed membrane domains. Reversible phosphorylation of LHC proteins (LHCPs) and PSII components appears to initiate most of the underlying regulatory mechanisms. An update on the roles of lipids, proteins, and protein complexes, as well as possible trafficking mechanisms, during thylakoid biogenesis and the de-etiolation process complements this review.
Collapse
Affiliation(s)
- Mathias Pribil
- Plant Molecular Biology, Department of Biology, Ludwig-Maximilians-University Munich (LMU), D-82152 Planegg-Martinsried, Germany
| | | | | |
Collapse
|
26
|
Musser RO, Hum-Musser SM, Gallucci M, DesRochers B, Brown JK. Microarray analysis of tomato plants exposed to the nonviruliferous or viruliferous whitefly vector harboring Pepper golden mosaic virus. JOURNAL OF INSECT SCIENCE (ONLINE) 2014; 14:230. [PMID: 25525099 PMCID: PMC5634132 DOI: 10.1093/jisesa/ieu092] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Accepted: 12/05/2013] [Indexed: 05/23/2023]
Abstract
Plants are routinely exposed to biotic and abiotic stresses to which they have evolved by synthesizing constitutive and induced defense compounds. Induced defense compounds are usually made, initially, at low levels; however, following further stimulation by specific kinds of biotic and abiotic stresses, they can be synthesized in relatively large amounts to abate the particular stress. cDNA microarray hybridization was used to identify an array of genes that were differentially expressed in tomato plants 15 d after they were exposed to feeding by nonviruliferous whiteflies or by viruliferous whiteflies carrying Pepper golden mosaic virus (PepGMV) (Begomovirus, Geminiviridae). Tomato plants inoculated by viruliferous whiteflies developed symptoms characteristic of PepGMV, whereas plants exposed to nonviruliferous whitefly feeding or nonwounded (negative) control plants exhibited no disease symptoms. The microarray analysis yielded over 290 spotted probes, with significantly altered expression of 161 putative annotated gene targets, and 129 spotted probes of unknown identities. The majority of the differentially regulated "known" genes were associated with the plants exposed to viruliferous compared with nonviruliferous whitefly feeding. Overall, significant differences in gene expression were represented by major physiological functions including defense-, pathogen-, photosynthesis-, and signaling-related responses and were similar to genes identified for other insect-plant systems. Viruliferous whitefly-stimulated gene expression was validated by real-time quantitative polymerase chain reaction of selected, representative candidate genes (messenger RNA): arginase, dehydrin, pathogenesis-related proteins 1 and -4, polyphenol oxidase, and several protease inhibitors. This is the first comparative profiling of the expression of tomato plants portraying different responses to biotic stress induced by viruliferous whitefly feeding (with resultant virus infection) compared with whitefly feeding only and negative control nonwounded plants exposed to neither. These results may be applicable to many other plant-insect-pathogen system interactions.
Collapse
Affiliation(s)
- Richard O Musser
- Department of Biological Sciences, Western Illinois University, Macomb, IL 61455
| | - Sue M Hum-Musser
- Department of Biological Sciences, Western Illinois University, Macomb, IL 61455
| | - Matthew Gallucci
- School of Plant Sciences, The University of Arizona, Tucson, AZ 85721
| | - Brittany DesRochers
- Department of Biological Sciences, Western Illinois University, Macomb, IL 61455
| | - Judith K Brown
- School of Plant Sciences, The University of Arizona, Tucson, AZ 85721
| |
Collapse
|
27
|
Dall'Osto L, Piques M, Ronzani M, Molesini B, Alboresi A, Cazzaniga S, Bassi R. The Arabidopsis nox mutant lacking carotene hydroxylase activity reveals a critical role for xanthophylls in photosystem I biogenesis. THE PLANT CELL 2013; 25:591-608. [PMID: 23396829 PMCID: PMC3608780 DOI: 10.1105/tpc.112.108621] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2012] [Revised: 01/15/2013] [Accepted: 01/18/2013] [Indexed: 05/05/2023]
Abstract
Carotenes, and their oxygenated derivatives xanthophylls, are essential components of the photosynthetic apparatus. They contribute to the assembly of photosynthetic complexes and participate in light absorption and chloroplast photoprotection. Here, we studied the role of xanthophylls, as distinct from that of carotenes, by characterizing a no xanthophylls (nox) mutant of Arabidopsis thaliana, which was obtained by combining mutations targeting the four carotenoid hydroxylase genes. nox plants retained α- and β-carotenes but were devoid in xanthophylls. The phenotype included depletion of light-harvesting complex (LHC) subunits and impairment of nonphotochemical quenching, two effects consistent with the location of xanthophylls in photosystem II antenna, but also a decreased efficiency of photosynthetic electron transfer, photosensitivity, and lethality in soil. Biochemical analysis revealed that the nox mutant was specifically depleted in photosystem I function due to a severe deficiency in PsaA/B subunits. While the stationary level of psaA/B transcripts showed no major differences between genotypes, the stability of newly synthesized PsaA/B proteins was decreased and translation of psaA/B mRNA was impaired in nox with respect to wild-type plants. We conclude that xanthophylls, besides their role in photoprotection and LHC assembly, are also needed for photosystem I core translation and stability, thus making these compounds indispensable for autotrophic growth.
Collapse
Affiliation(s)
- Luca Dall'Osto
- Dipartimento di Biotecnologie, Università di Verona, 37134 Verona, Italy.
| | | | | | | | | | | | | |
Collapse
|
28
|
Liu J, Yang H, Lu Q, Wen X, Chen F, Peng L, Zhang L, Lu C. PsbP-domain protein1, a nuclear-encoded thylakoid lumenal protein, is essential for photosystem I assembly in Arabidopsis. THE PLANT CELL 2012; 24:4992-5006. [PMID: 23221595 PMCID: PMC3556971 DOI: 10.1105/tpc.112.106542] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
To gain insights into the molecular details of photosystem I (PSI) biogenesis, we characterized the PsbP-domain protein1 (ppd1) mutant of Arabidopsis thaliana that specifically lacks PSI activity. Deletion of PPD1 results in an inability of the mutant to grow photoautotrophically and a specific loss of the stable PSI complex. Unaltered transcription and translation of plastid-encoded PSI genes indicate that PPD1 acts at the posttranslational level. In vivo protein labeling experiments reveal that the rate of synthesis of PSI reaction center proteins PsaA/B in ppd1 is comparable to that of wild-type plants, whereas the rate of turnover of PsaA/B proteins is higher in ppd1 than in wild-type plants. With increasing leaf age, PPD1 content decreases considerably, while PSI content remains constant. PPD1 is a nuclear-encoded thylakoid lumenal protein and is associated with PSI but is not an integral subunit of PSI. Biochemical and molecular analyses reveal that PPD1 interacts directly and specifically with PsaB and PsaA. Yeast two-hybrid experiments show that PPD1 interacts with some lumenal loops of PsaB and PsaA. Our results suggest that PPD1 is a PSI assembly factor that assists the proper folding and integration of PsaB and PsaA into the thylakoid membrane.
Collapse
Affiliation(s)
- Jun Liu
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- Graduate University of Chinese Academy of Sciences, Beijing 100049, China
| | - Huixia Yang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Qingtao Lu
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Xiaogang Wen
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Fan Chen
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Lianwei Peng
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Lixin Zhang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- National Center for Plant Gene Research, Beijing 100093, China
| | - Congming Lu
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- National Center for Plant Gene Research, Beijing 100093, China
- Address correspondence to
| |
Collapse
|
29
|
Kargul J, Janna Olmos JD, Krupnik T. Structure and function of photosystem I and its application in biomimetic solar-to-fuel systems. JOURNAL OF PLANT PHYSIOLOGY 2012; 169:1639-1653. [PMID: 22784471 DOI: 10.1016/j.jplph.2012.05.018] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Revised: 05/09/2012] [Accepted: 05/11/2012] [Indexed: 06/01/2023]
Abstract
Photosystem I (PSI) is one of the most efficient biological macromolecular complexes that converts solar energy into condensed energy of chemical bonds. Despite high structural complexity, PSI operates with a quantum yield close to 1.0 and to date, no man-made synthetic system approached this remarkable efficiency. This review highlights recent developments in dissecting molecular structure and function of the prokaryotic and eukaryotic PSI. It also overviews progress in the application of this complex as a natural photocathode for production of hydrogen within the biomimetic solar-to-fuel nanodevices.
Collapse
Affiliation(s)
- Joanna Kargul
- Department of Plant Molecular Physiology, University of Warsaw, ul. Miecznikowa 1, 02-096 Warsaw, Poland.
| | | | | |
Collapse
|
30
|
Kim BH, Malec P, Waloszek A, von Arnim AG. Arabidopsis BPG2: a phytochrome-regulated gene whose protein product binds to plastid ribosomal RNAs. PLANTA 2012; 236:677-90. [PMID: 22526496 DOI: 10.1007/s00425-012-1638-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2012] [Accepted: 03/22/2012] [Indexed: 05/08/2023]
Abstract
BPG2 (Brz-insensitive pale green 2) is a dark-repressible and light-inducible gene that is required for the greening process in Arabidopsis. Light pulse experiments suggested that light-regulated gene expression of BPG2 is mediated by phytochrome. The T-DNA insertion mutant bpg2-2 exhibited a reduced level of chlorophyll and carotenoid pigmentation in the plastids. Measurements of time resolved chlorophyll fluorescence and of fluorescence emission at 77 K indicated defective photosystem II and altered photosystem I functions in bpg2 mutants. Kinetic analysis of chlorophyll fluorescence induction suggested that the reduction of the primary acceptor (QA) is impaired in bpg2. The observed alterations resulted in reduced photosynthetic efficiency as measured by the electron transfer rate. BPG2 protein is localized in the plastid stroma fraction. Co-immunoprecipitation of a formaldehyde cross-linked RNA-protein complex indicated that BPG2 protein binds with specificity to chloroplast 16S and 23S ribosomal RNAs. The direct physical interaction with the plastid rRNAs supports an emerging model whereby BPG2 provides light-regulated ribosomal RNA processing functions, which are rate limiting for development of the plastid and its photosynthetic apparatus.
Collapse
Affiliation(s)
- Byung-Hoon Kim
- Department of Natural Sciences, Albany State University, 504 College Drive, Albany, GA 31705, USA.
| | | | | | | |
Collapse
|
31
|
Ye JW, Gong ZY, Chen CG, Mi HL, Chen GY. A mutation of OSOTP 51 leads to impairment of photosystem I complex assembly and serious photo-damage in rice. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2012; 54:87-98. [PMID: 22353560 DOI: 10.1111/j.1744-7909.2012.01094.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Gene expression in chloroplasts is regulated by many nuclear-encoded proteins. In this study, we isolated a rice (Oryza sativa subsp. japonica) mutant osotp51 with significant reduction in photosystem I (PSI). The osotp51 is extremely sensitive to light and accumulates a higher level of reactive oxygen species. Its leaves are almost albino when grown at 40 μmol photons/m(2) per s. However, grown at 4 μmol photons/m(2) per s, osotp51 has a similar phenotype to the wild-type. 77K chlorophyll fluorescence analysis showed a blue shift in the highest peak emission from PSI in osotp51. In addition, the level of PSI and PSII dimer is dramatically reduced in osotp51. OSOTP 51 encodes a pentatricopeptide repeats protein, homologous to organelle transcript processing 51 in Arabidopsis. Loss-of-function OSOTP51 affects intron splicing of a number of plastid genes, particularly the ycf3 coding a protein involved in the assembly of PSI complex. OSOTP51 is functionally conserved in higher plants. The mutation of osotp51 indirectly leads to a widespread change in the structure and functions of PSI, results in severe photoinhibition, and finally dies, even when grown under very low light intensity.
Collapse
Affiliation(s)
- Jian-Wei Ye
- National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | | | | | | | | |
Collapse
|
32
|
Schöttler MA, Albus CA, Bock R. Photosystem I: its biogenesis and function in higher plants. JOURNAL OF PLANT PHYSIOLOGY 2011; 168:1452-61. [PMID: 21255865 DOI: 10.1016/j.jplph.2010.12.009] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2010] [Revised: 12/21/2010] [Accepted: 12/21/2010] [Indexed: 05/06/2023]
Abstract
Photosystem I (PSI), the plastocyanin-ferredoxin oxidoreductase of the photosynthetic electron transport chain, is one of the largest bioenergetic complexes known. It is composed of subunits encoded in both the chloroplast genome and the nuclear genome and thus, its assembly requires an intricate coordination of gene expression and intensive communication between the two compartments. In this review, we first briefly describe PSI structure and then focus on recent findings on the role of the two small chloroplast genome-encoded subunits PsaI and PsaJ in the stability and function of PSI in higher plants. We then address the sequence of PSI biogenesis, discuss the role of auxiliary proteins involved in cofactor insertion into the PSI apoproteins and in the establishment of protein-protein interactions during subunit assembly. Finally, we consider potential limiting steps of PSI biogenesis, and how they may contribute to the control of PSI accumulation.
Collapse
Affiliation(s)
- Mark Aurel Schöttler
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, Potsdam-Golm, Germany.
| | | | | |
Collapse
|
33
|
Busch A, Hippler M. The structure and function of eukaryotic photosystem I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1807:864-77. [PMID: 20920463 DOI: 10.1016/j.bbabio.2010.09.009] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2010] [Revised: 09/20/2010] [Accepted: 09/28/2010] [Indexed: 12/27/2022]
Abstract
Eukaryotic photosystem I consists of two functional moieties: the photosystem I core, harboring the components for the light-driven charge separation and the subsequent electron transfer, and the peripheral light-harvesting complex (LHCI). While the photosystem I-core remained highly conserved throughout the evolution, with the exception of the oxidizing side of photosystem I, the LHCI complex shows a high degree of variability in size, subunits composition and bound pigments, which is due to the large variety of different habitats photosynthetic organisms dwell in. Besides summarizing the most current knowledge on the photosystem I-core structure, we will discuss the composition and structure of the LHCI complex from different eukaryotic organisms, both from the red and the green clade. Furthermore, mechanistic insights into electron transfer between the donor and acceptor side of photosystem I and its soluble electron transfer carrier proteins will be given. This article is part of a Special Issue entitled: Regulation of Electron Transport in Chloroplasts.
Collapse
Affiliation(s)
- Andreas Busch
- Department of Plant Biology and Biotechnology, Faculty of Life Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark.
| | | |
Collapse
|
34
|
Lütken H, Lloyd JR, Glaring MA, Baunsgaard L, Laursen KH, Haldrup A, Kossmann J, Blennow A. Repression of both isoforms of disproportionating enzyme leads to higher malto-oligosaccharide content and reduced growth in potato. PLANTA 2010; 232:1127-39. [PMID: 20700743 DOI: 10.1007/s00425-010-1245-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2010] [Accepted: 07/29/2010] [Indexed: 05/29/2023]
Abstract
Two glucanotransferases, disproportionating enzyme 1 (StDPE1) and disproportionating enzyme 2 (StDPE2), were repressed using RNA interference technology in potato, leading to plants repressed in either isoform individually, or both simultaneously. This is the first detailed report of their combined repression. Plants lacking StDPE1 accumulated slightly more starch in their leaves than control plants and high levels of maltotriose, while those lacking StDPE2 contained maltose and large amounts of starch. Plants repressed in both isoforms accumulated similar amounts of starch to those lacking StDPE2. In addition, they contained a range of malto-oligosaccharides from maltose to maltoheptaose. Plants repressed in both isoforms had chlorotic leaves and did not grow as well as either the controls or lines where only one of the isoforms was repressed. Examination of photosynthetic parameters suggested that this was most likely due to a decrease in carbon assimilation. The subcellular localisation of StDPE2 was re-addressed in parallel with DPE2 from Arabidopsis thaliana by transient expression of yellow fluorescent protein fusions in tobacco. No translocation to the chloroplasts was observed for any of the fusion proteins, supporting a cytosolic role of the StDPE2 enzyme in leaf starch metabolism, as has been observed for Arabidopsis DPE2. It is concluded that StDPE1 and StDPE2 have individual essential roles in starch metabolism in potato and consequently repression of these disables regulation of leaf malto-oligosaccharides, starch content and photosynthetic activity and thereby plant growth possibly by a negative feedback mechanism.
Collapse
Affiliation(s)
- Henrik Lütken
- Department of Plant Biology and Biotechnology, University of Copenhagen, Frederiksberg C, Denmark.
| | | | | | | | | | | | | | | |
Collapse
|
35
|
Jung HS, Okegawa Y, Shih PM, Kellogg E, Abdel-Ghany SE, Pilon M, Sjölander K, Shikanai T, Niyogi KK. Arabidopsis thaliana PGR7 encodes a conserved chloroplast protein that is necessary for efficient photosynthetic electron transport. PLoS One 2010; 5:e11688. [PMID: 20657737 PMCID: PMC2908147 DOI: 10.1371/journal.pone.0011688] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Accepted: 06/22/2010] [Indexed: 11/18/2022] Open
Abstract
A significant fraction of a plant's nuclear genome encodes chloroplast-targeted proteins, many of which are devoted to the assembly and function of the photosynthetic apparatus. Using digital video imaging of chlorophyll fluorescence, we isolated proton gradient regulation 7 (pgr7) as an Arabidopsis thaliana mutant with low nonphotochemical quenching of chlorophyll fluorescence (NPQ). In pgr7, the xanthophyll cycle and the PSBS gene product, previously identified NPQ factors, were still functional, but the efficiency of photosynthetic electron transport was lower than in the wild type. The pgr7 mutant was also smaller in size and had lower chlorophyll content than the wild type in optimal growth conditions. Positional cloning located the pgr7 mutation in the At3g21200 (PGR7) gene, which was predicted to encode a chloroplast protein of unknown function. Chloroplast targeting of PGR7 was confirmed by transient expression of a GFP fusion protein and by stable expression and subcellular localization of an epitope-tagged version of PGR7. Bioinformatic analyses revealed that the PGR7 protein has two domains that are conserved in plants, algae, and bacteria, and the N-terminal domain is predicted to bind a cofactor such as FMN. Thus, we identified PGR7 as a novel, conserved nuclear gene that is necessary for efficient photosynthetic electron transport in chloroplasts of Arabidopsis.
Collapse
Affiliation(s)
- Hou-Sung Jung
- Department of Plant and Microbial Biology, University of California, Berkeley, California, United States of America
| | - Yuki Okegawa
- Graduate School of Agriculture, Kyushu University, Fukuoka, Japan
- Department of Botany, Graduate School of Science, Kyoto University, Kyoto, Japan
| | - Patrick M. Shih
- Department of Plant and Microbial Biology, University of California, Berkeley, California, United States of America
| | - Elizabeth Kellogg
- Department of Bioengineering, University of California, Berkeley, California, United States of America
| | - Salah E. Abdel-Ghany
- Biology Department, Colorado State University, Fort Collins, Colorado, United States of America
| | - Marinus Pilon
- Biology Department, Colorado State University, Fort Collins, Colorado, United States of America
| | - Kimmen Sjölander
- Department of Plant and Microbial Biology, University of California, Berkeley, California, United States of America
- Department of Bioengineering, University of California, Berkeley, California, United States of America
| | - Toshiharu Shikanai
- Department of Botany, Graduate School of Science, Kyoto University, Kyoto, Japan
| | - Krishna K. Niyogi
- Department of Plant and Microbial Biology, University of California, Berkeley, California, United States of America
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America
| |
Collapse
|
36
|
Ozawa SI, Onishi T, Takahashi Y. Identification and characterization of an assembly intermediate subcomplex of photosystem I in the green alga Chlamydomonas reinhardtii. J Biol Chem 2010; 285:20072-9. [PMID: 20413595 DOI: 10.1074/jbc.m109.098954] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Photosystem I (PSI) is a multiprotein complex consisting of the PSI core and peripheral light-harvesting complex I (LHCI) that together form the PSI-LHCI supercomplex in algae and higher plants. The supercomplex is synthesized in steps during which 12-15 core and 4-9 LHCI subunits are assembled. Here we report the isolation of a PSI subcomplex that separated on a sucrose density gradient from the thylakoid membranes isolated from logarithmic growth phase cells of the green alga Chlamydomonas reinhardtii. Pulse-chase labeling of total cellular proteins revealed that the subcomplex was synthesized de novo within 1 min and was converted to the mature PSI-LHCI during the 2-h chase period, indicating that the subcomplex was an assembly intermediate. The subcomplex was functional; it photo-oxidized P700 and demonstrated electron transfer activity. The subcomplex lacked PsaK and PsaG, however, and it bound PsaF and PsaJ weakly and was not associated with LHCI. It seemed likely that LHCI had been integrated into the subcomplex unstably and was dissociated during solubilization and/or fractionation. We, thus, infer that PsaK and PsaG stabilize the association between PSI core and LHCI complexes and that PsaK and PsaG bind to the PSI core complex after the integration of LHCI in one of the last steps of PSI complex assembly.
Collapse
Affiliation(s)
- Shin-Ichiro Ozawa
- Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Kita-ku, Tsushima-naka, Okayama 700-8530, Japan
| | | | | |
Collapse
|
37
|
Landau AM, Lokstein H, Scheller HV, Lainez V, Maldonado S, Prina AR. A cytoplasmically inherited barley mutant is defective in photosystem I assembly due to a temperature-sensitive defect in ycf3 splicing. PLANT PHYSIOLOGY 2009; 151:1802-11. [PMID: 19812182 PMCID: PMC2785965 DOI: 10.1104/pp.109.147843] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2009] [Accepted: 10/05/2009] [Indexed: 05/20/2023]
Abstract
A cytoplasmically inherited chlorophyll-deficient mutant of barley (Hordeum vulgare) termed cytoplasmic line 3 (CL3), displaying a viridis (homogeneously light-green colored) phenotype, has been previously shown to be affected by elevated temperatures. In this article, biochemical, biophysical, and molecular approaches were used to study the CL3 mutant under different temperature and light conditions. The results lead to the conclusion that an impaired assembly of photosystem I (PSI) under higher temperatures and certain light conditions is the primary cause of the CL3 phenotype. Compromised splicing of ycf3 transcripts, particularly at elevated temperature, resulting from a mutation in a noncoding region (intron 1) in the mutant ycf3 gene results in a defective synthesis of Ycf3, which is a chaperone involved in PSI assembly. The defective PSI assembly causes severe photoinhibition and degradation of PSII.
Collapse
Affiliation(s)
- Alejandra Mabel Landau
- Centro de Investigaciones en Ciencias Veterinarias y Agronómicas, Instituto Nacional de Tecnología Agropecuaria, B1712WAA Castelar, Province of Buenos Aires, Argentina.
| | | | | | | | | | | |
Collapse
|
38
|
Amunts A, Toporik H, Borovikova A, Nelson N. Structure determination and improved model of plant photosystem I. J Biol Chem 2009; 285:3478-86. [PMID: 19923216 DOI: 10.1074/jbc.m109.072645] [Citation(s) in RCA: 192] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Photosystem I functions as a sunlight energy converter, catalyzing one of the initial steps in driving oxygenic photosynthesis in cyanobacteria, algae, and higher plants. Functionally, Photosystem I captures sunlight and transfers the excitation energy through an intricate and precisely organized antenna system, consisting of a pigment network, to the center of the molecule, where it is used in the transmembrane electron transfer reaction. Our current understanding of the sophisticated mechanisms underlying these processes has profited greatly from elucidation of the crystal structures of the Photosystem I complex. In this report, we describe the developments that ultimately led to enhanced structural information of plant Photosystem I. In addition, we report an improved crystallographic model at 3.3-A resolution, which allows analysis of the structure in more detail. An improved electron density map yielded identification and tracing of subunit PsaK. The location of an additional ten beta-carotenes as well as five chlorophylls and several loop regions, which were previously uninterpretable, are now modeled. This represents the most complete plant Photosystem I structure obtained thus far, revealing the locations of and interactions among 17 protein subunits and 193 non-covalently bound photochemical cofactors. Using the new crystal structure, we examine the network of contacts among the protein subunits from the structural perspective, which provide the basis for elucidating the functional organization of the complex.
Collapse
Affiliation(s)
- Alexey Amunts
- Biochemistry Department, George S Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | | | | | | |
Collapse
|
39
|
Yu QB, Jiang Y, Chong K, Yang ZN. AtECB2, a pentatricopeptide repeat protein, is required for chloroplast transcript accD RNA editing and early chloroplast biogenesis in Arabidopsis thaliana. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2009; 59:1011-23. [PMID: 19500301 DOI: 10.1111/j.1365-313x.2009.03930.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Chloroplast biogenesis is a complex process in higher plants. Screening chloroplast biogenesis mutants, and elucidating their molecular mechanisms, will provide insight into the process of chloroplast biogenesis. In this paper, we obtained an early chloroplast biogenesis mutant atecb2 that displayed albino cotyledons and was seedling lethal. Microscopy observations revealed that the chloroplast of atecb2 mutants lacked an organized thylakoid membrane. The AtECB2 gene, which is highly expressed in cotyledons and seedlings, encodes a pentatricopeptide repeat protein (PPR) with a C-terminal DYW domain. The AtECB2 protein is localized in the chloroplast, and contains a conserved HxEx(n)CxxC motif that is similar to the activated site of cytidine deaminase. The AtECB2 mutation affects the expression pattern of plastid-encoded genes. Immunoblot analyses showed that the levels of photosynthetic proteins decreased substantially in atecb2 mutants. Inspection of all reported plastid RNA editing sites revealed that one editing site, accD, is not edited in atecb2 mutants. Therefore, the AtECB2 protein must regulate the RNA editing of this site, and the dysfunctional AccD protein from the unedited RNA molecules could lead to the mutated phenotype. All of these results indicate that AtECB2 is required for chloroplast transcript accD RNA editing and early chloroplast biogenesis in Arabidopsis thaliana.
Collapse
Affiliation(s)
- Qing-Bo Yu
- Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | | | | | | |
Collapse
|
40
|
Oh MH, Safarova RB, Eu YJ, Zulfugarov IS, Kim JH, Hwang HJ, Lee CB, Lee CH. Loss of peripheral polypeptides in the stromal side of photosystem I by light-chilling in cucumber leaves. Photochem Photobiol Sci 2009; 8:535-41. [PMID: 19337668 DOI: 10.1039/b817808a] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2008] [Accepted: 01/30/2009] [Indexed: 11/21/2022]
Abstract
Photosystem I (PSI) is severely damaged by chilling at 4 degrees C in low light, especially in the chilling sensitive plant cucumber. To investigate the early events in PSI photoinhibition, we examined structural changes in the level of pigment-protein complexes in cucumber leaves in comparison with pea leaves. The complexes were separated on a native green gel and an increase in the intensity of a band was observed only in light-chilled cucumber leaves. The 77 K fluorescence emission spectrum of this green band indicated that the band was mainly composed of PSI with light-harvesting complex I. Each lane was cut from the green gel and separated on a fully denaturing SDS-PAGE in the second dimension. The new green gel band observed after light-chilling in cucumber leaves lacked 19, 18, and 16.5 kDa polypeptides. These results suggest that light-chilling facilitates the release of three peripheral polypeptides as an early event of chilling stress in vivo, which results in the inactivation of PSI in intact cucumber leaves.
Collapse
Affiliation(s)
- Min-Hyuk Oh
- Department of Molecular Biology, Pusan National University, Busan 609-735, Korea
| | | | | | | | | | | | | | | |
Collapse
|
41
|
Pesaresi P, Scharfenberg M, Weigel M, Granlund I, Schröder WP, Finazzi G, Rappaport F, Masiero S, Furini A, Jahns P, Leister D. Mutants, overexpressors, and interactors of Arabidopsis plastocyanin isoforms: revised roles of plastocyanin in photosynthetic electron flow and thylakoid redox state. MOLECULAR PLANT 2009; 2:236-48. [PMID: 19825610 DOI: 10.1093/mp/ssn041] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Two homologous plastocyanin isoforms are encoded by the genes PETE1 and PETE2 in the nuclear genome of Arabidopsis thaliana. The PETE2 transcript is expressed at considerably higher levels and the PETE2 protein is the more abundant isoform. Null mutations in the PETE genes resulted in plants, designated pete1 and pete2, with decreased plastocyanin contents. However, despite reducing plastocyanin levels by over approximately 90%, a pete2 null mutation on its own affects rates of photosynthesis and growth only slightly, whereas pete1 knockout plants, with about 60-80% of the wild-type plastocyanin level, did not show any alteration. Hence, plastocyanin concentration is not limiting for photosynthetic electron flow under optimal growth conditions, perhaps implying other possible physiological roles for the protein. Indeed, plastocyanin has been proposed previously to cooperate with cytochrome c(6A) (Cyt c(6A)) in thylakoid redox reactions, but we find no evidence for a physical interaction between the two proteins, using interaction assays in yeast. We observed homodimerization of Cyt c(6A) in yeast interaction assays, but also Cyt c(6A) homodimers failed to interact with plastocyanin. Moreover, phenotypic analysis of atc6-1 pete1 and atc6-1 pete2 double mutants, each lacking Cyt c(6A) and one of the two plastocyanin-encoding genes, failed to reveal any genetic interaction. Overexpression of either PETE1 or PETE2 in the pete1 pete2 double knockout mutant background results in essentially wild-type photosynthetic performance, excluding the possibility that the two plastocyanin isoforms could have distinct functions in thylakoid electron flow.
Collapse
Affiliation(s)
- Paolo Pesaresi
- Dipartimento di Produzione Vegetale, Università degli studi di Milano c/o Parco Tecnologico Padano Via Einstein, Loc. Cascina Codazza, I-26900 Lodi, Italy
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
42
|
Ströher E, Dietz KJ. The dynamic thiol-disulphide redox proteome of the Arabidopsis thaliana chloroplast as revealed by differential electrophoretic mobility. PHYSIOLOGIA PLANTARUM 2008; 133:566-83. [PMID: 18433418 DOI: 10.1111/j.1399-3054.2008.01103.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The dynamics of the thiol-disulphide redox proteome is central to cell function and its regulation. Altered mobility of proteins in the oxidized and reduced state allows the MS-based identification of those thiol-disulphide proteins that undergo major conformational changes. A proteomic approach was taken with thylakoid-bound, luminal and ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco)-less stromal subproteome fractions of the chloroplast from Arabidopsis thaliana. Among the 49 verified polypeptides were 22 novel redox proteins, previously not reported as being part of the redox proteome. Among the redox-affected proteins were PsbA (D1), PsaA1 and PsaF, chloroplast monodehydroascorbate reductase and also the Deg1 protease. Recombinant Deg1 and Deg2 revealed redox dependence of their proteolytic activity. The data provide new insights into the redox network of the chloroplast.
Collapse
Affiliation(s)
- Elke Ströher
- Faculty of Biology, University of Bielefeld, Univ. Str. 25, D-33501 Bielefeld, Germany
| | | |
Collapse
|
43
|
Jensen PE, Bassi R, Boekema EJ, Dekker JP, Jansson S, Leister D, Robinson C, Scheller HV. Structure, function and regulation of plant photosystem I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2007; 1767:335-52. [PMID: 17442259 DOI: 10.1016/j.bbabio.2007.03.004] [Citation(s) in RCA: 168] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2007] [Revised: 03/03/2007] [Accepted: 03/06/2007] [Indexed: 12/20/2022]
Abstract
Photosystem I (PSI) is a multisubunit protein complex located in the thylakoid membranes of green plants and algae, where it initiates one of the first steps of solar energy conversion by light-driven electron transport. In this review, we discuss recent progress on several topics related to the functioning of the PSI complex, like the protein composition of the complex in the plant Arabidopsis thaliana, the function of these subunits and the mechanism by which nuclear-encoded subunits can be inserted into or transported through the thylakoid membrane. Furthermore, the structure of the native PSI complex in several oxygenic photosynthetic organisms and the role of the chlorophylls and carotenoids in the antenna complexes in light harvesting and photoprotection are reviewed. The special role of the 'red' chlorophylls (chlorophyll molecules that absorb at longer wavelength than the primary electron donor P700) is assessed. The physiology and mechanism of the association of the major light-harvesting complex of photosystem II (LHCII) with PSI during short term adaptation to changes in light quality and quantity is discussed in functional and structural terms. The mechanism of excitation energy transfer between the chlorophylls and the mechanism of primary charge separation is outlined and discussed. Finally, a number of regulatory processes like acclimatory responses and retrograde signalling is reviewed with respect to function of the thylakoid membrane. We finish this review by shortly discussing the perspectives for future research on PSI.
Collapse
Affiliation(s)
- Poul Erik Jensen
- Plant Biochemistry Laboratory, Department of Plant Biology, Faculty of Life Science, University of Copenhagen, DK-1871 Frederiksberg C, Denmark.
| | | | | | | | | | | | | | | |
Collapse
|
44
|
Hansson A, Amann K, Zygadlo A, Meurer J, Scheller HV, Jensen PE. Knock-out of the chloroplast-encoded PSI-J subunit of photosystem I in Nicotiana tabacum. FEBS J 2007; 274:1734-46. [PMID: 17331187 DOI: 10.1111/j.1742-4658.2007.05722.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The plastid-encoded psaJ gene encodes a hydrophobic low-molecular-mass subunit of photosystem I (PSI) containing one transmembrane helix. Homoplastomic transformants with an inactivated psaJ gene were devoid of PSI-J protein. The mutant plants were slightly smaller and paler than wild-type because of a 13% reduction in chlorophyll content per leaf area caused by an approximately 20% reduction in PSI. The amount of the peripheral antenna proteins, Lhca2 and Lhca3, was decreased to the same level as the core subunits, but Lhca1 and Lhca4 were present in relative excess. The functional size of the PSI antenna was not affected, suggesting that PSI-J is not involved in binding of light-harvesting complex I. The specific PSI activity, measured as NADP(+) photoreduction in vitro, revealed a 55% reduction in electron transport through PSI in the mutant. No significant difference in the second-order rate constant for electron transfer from reduced plastocyanin to oxidized P700 was observed in the absence of PSI-J. Instead, a large fraction of PSI was found to be inactive. Immunoblotting analysis revealed a secondary loss of the luminal PSI-N subunit in PSI particles devoid of PSI-J. Presumably PSI-J affects the conformation of PSI-F, which in turn affects the binding of PSI-N. This together renders a fraction of the PSI particles inactive. Thus, PSI-J is an important subunit that, together with PSI-F and PSI-N, is required for formation of the plastocyanin-binding domain of PSI. PSI-J is furthermore important for stability or assembly of the PSI complex.
Collapse
Affiliation(s)
- Andreas Hansson
- Plant Biochemistry Laboratory, Department of Plant Biology, Faculty of Life Sciences, University of Copenhagen, Frederiksberg, Denmark
| | | | | | | | | | | |
Collapse
|
45
|
Lefebvre-Legendre L, Rappaport F, Finazzi G, Ceol M, Grivet C, Hopfgartner G, Rochaix JD. Loss of phylloquinone in Chlamydomonas affects plastoquinone pool size and photosystem II synthesis. J Biol Chem 2007; 282:13250-63. [PMID: 17339322 DOI: 10.1074/jbc.m610249200] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Phylloquinone functions as the electron transfer cofactor at the A(1) site of photosystem I. We have isolated and characterized a mutant of Chlamydomonas reinhardtii, menD1, that is deficient in MenD, which encodes 2-succinyl-6-hydroxy-2,4-cyclohexadiene-1-carboxylate synthase, an enzyme that catalyzes the first specific step of the phylloquinone biosynthetic pathway. The mutant is photosynthetically active but light-sensitive. Analysis of total pigments by mass spectrometry reveals that phylloquinone is absent in menD1, but plastoquinone levels are not affected. This is further confirmed by the rescue of menD1 by addition of phylloquinone to the growth medium. Analysis of electron transfer by absorption spectroscopy indicates that plastoquinone replaces phylloquinone in photosystem I and that electron transfer from A(1) to the iron-sulfur centers is slowed down at least 40-fold. Consistent with a replacement of phylloquinone by plastoquinone, the size of the free plastoquinone pool of menD1 is reduced by 20-30%. In contrast to cyanobacterial MenD-deficient mutants, photosystem I accumulates normally in menD1, whereas the level of photosystem II declines. This decrease is because of reduced synthesis of the photosystem II core subunits. The relationship between plastoquinone occupancy of the A(1) site in photosystem I and the reduced accumulation of photosystem II is discussed.
Collapse
Affiliation(s)
- Linnka Lefebvre-Legendre
- Department of Molecular Biology, University of Geneva, 30, Quai Ernest Ansermet 1211 Geneva 4, Switzerland
| | | | | | | | | | | | | |
Collapse
|
46
|
Teardo E, de Laureto PP, Bergantino E, Dalla Vecchia F, Rigoni F, Szabò I, Giacometti GM. Evidences for interaction of PsbS with photosynthetic complexes in maize thylakoids. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2006; 1767:703-11. [PMID: 17250801 DOI: 10.1016/j.bbabio.2006.12.002] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2006] [Revised: 11/27/2006] [Accepted: 12/03/2006] [Indexed: 11/21/2022]
Abstract
The PsbS subunit of Photosystem II (PSII) has received much attention in the past few years, given its crucial role in photoprotection of higher plants. The exact location of this small subunit in thylakoids is also debated. In this work possible interaction partners of PsbS have been identified by immunoaffinity and immunoprecipitation, performed with mildly solubilized whole thylakoid membrane. The interacting proteins, as identified by mass spectrometry analysis of the immunoaffinity eluate, include CP29, some LHCII components, but also components of Photosystem I, of the cytochrome b(6)f complex as well as of ATP synthase. These proteins can be co-immunoprecipitated by using highly specific anti-PsbS antibodies and, vice-versa, PsbS is co-immunoprecipitated by antisera against components of the interacting complexes. We also find that PsbS co-migrates with bands containing PSII, ATP synthase and cytochrome b(6)f as well as with LHCII-containing bands on non-denaturing Deriphat PAGE. These results suggest multiple location of PsbS in the thylakoid membrane and point to an unexpected lateral mobility of this PSII subunit. As revealed by immunogold labelling with antibody against PsbS, the protein is associated either with granal membranes or prevalently with stroma lamellae in low or high-intensity light-treated intact leaves, respectively. This finding is consistent with the capability of PsbS to interact with complexes located in stroma lamellae, even though the exact physiological condition(s) under which these interactions may take place remain to be clarified.
Collapse
Affiliation(s)
- Enrico Teardo
- Department of Biology, University of Padova, Viale G. Colombo 3, 35131 Padua, Italy
| | | | | | | | | | | | | |
Collapse
|
47
|
Sommer F, Drepper F, Haehnel W, Hippler M. Identification of precise electrostatic recognition sites between cytochrome c6 and the photosystem I subunit PsaF using mass spectrometry. J Biol Chem 2006; 281:35097-103. [PMID: 16984911 DOI: 10.1074/jbc.m607384200] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The reduction of the photo-oxidized special chlorophyll pair P700 of photosystem I (PSI) in the photosynthetic electron transport chain of eukaryotic organisms is facilitated by the soluble copper-containing protein plastocyanin (pc). In the absence of copper, pc is functionally replaced by the heme-containing protein cytochrome c6 (cyt c6) in the green alga Chlamydomonas reinhardtii. Binding and electron transfer between both donors and PSI follows a two-step mechanism that depends on electrostatic and hydrophobic recognition between the partners. Although the electrostatic and hydrophobic recognition sites on pc and PSI are well known, the precise electrostatic recognition site on cyt c6 is unknown. To specify the interaction sites on a molecular level, we cross-linked cyt c6 and PSI using a zero-length cross-linker and obtained a cross-linked complex competent in fast and efficient electron transfer. As shown previously, cyt c6 cross-links specifically with the PsaF subunit of PSI. Mass spectrometric analysis of tryptic peptides from the cross-linked product revealed specific interaction sites between residues Lys27 of PsaF and Glu69 of cyt c6 and between Lys23 of PsaF and Glu69/Glu70 of cyt c6. Using these new data, we present a molecular model of the intermolecular electron transfer complex between eukaryotic cyt c6 and PSI.
Collapse
Affiliation(s)
- Frederik Sommer
- Institute of Plant Science, Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | | | | | | |
Collapse
|
48
|
Stöckel J, Bennewitz S, Hein P, Oelmüller R. The evolutionarily conserved tetratrico peptide repeat protein pale yellow green7 is required for photosystem I accumulation in Arabidopsis and copurifies with the complex. PLANT PHYSIOLOGY 2006; 141:870-8. [PMID: 16679416 PMCID: PMC1489899 DOI: 10.1104/pp.106.078147] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Pale yellow green7-1 (pyg7-1) is a photosystem I (PSI)-deficient Arabidopsis (Arabidopsis thaliana) mutant. PSI subunits are synthesized in the mutant, but do not assemble into a stable complex. In contrast, light-harvesting antenna proteins of both photosystems accumulate in the mutant. Deletion of Pyg7 results in severely reduced growth rates, alterations in leaf coloration, and plastid ultrastructure. Pyg7 was isolated by map-based cloning and encodes a tetratrico peptide repeat protein with homology to Ycf37 from Synechocystis. The protein is localized in the chloroplast associated with thylakoid membranes and copurifies with PSI. An independent pyg7 T-DNA insertion line, pyg7-2, exhibits the same phenotype. pyg7 gene expression is light regulated. Comparison of the roles of Ycf37 in cyanobacteria and Pyg7 in higher plants suggests that the ancient protein has altered its function during evolution. Whereas the cyanobacterial protein mediates more efficient PSI accumulation, the higher plant protein is absolutely required for complex assembly or maintenance.
Collapse
Affiliation(s)
- Jana Stöckel
- Institut für Allgemeine Botanik und Pflanzenphysiologie, Friedrich Schiller University, 07747 Jena, Germany
| | | | | | | |
Collapse
|
49
|
Chow WS, Kim EH, Horton P, Anderson JM. Granal stacking of thylakoid membranes in higher plant chloroplasts: the physicochemical forces at work and the functional consequences that ensue. Photochem Photobiol Sci 2005; 4:1081-90. [PMID: 16307126 DOI: 10.1039/b507310n] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The formation of grana in chloroplasts of higher plants is examined in terms of the subtle interplay of physicochemical forces of attraction and repulsion. The attractive forces between two adjacent membranes comprise (1) van der Waals attraction that depends on the abundance and type of atoms in each membrane, on the distance between the membranes and on the dielectric constant, (2) depletion attraction that generates local order by granal stacking at the expense of greater disorder (i.e. entropy) in the stroma, and (3) an electrostatic attraction of opposite charges located on adjacent membranes. The repulsive forces comprise (1) electrostatic repulsion due to the net negative charge on the outer surface of thylakoid membranes, (2) hydration repulsion that operates at small separations between thylakoid membranes due to layers of bound water molecules, and (3) steric hindrance due to bulky protrusions of Photosystem I (PSI) and ATP synthase into the stroma. In addition, specific interactions may occur, but they await experimental demonstration. Although grana are not essential for photosynthesis, they are ubiquitous in higher plants. Grana may have been selected during evolution for the functional advantages that they confer on higher plants. The functional consequences of grana stacking include (1) enhancement of light capture through a vastly increased area-to-volume ratio and connectivity of several PSIIs with large functional antenna size, (2) the ability to control the lateral separation of PSI from PSII and, therefore, the balanced distribution of excitation energy between two photosystems working in series, (3) the reversible fine-tuning of energy distribution between the photosystems by State 1-State 2 transitions, (4) the ability to regulate light-harvesting via controlled thermal dissipation of excess excitation energy, detected as non-photochemical quenching, (5) dynamic flexibility in the light reactions mediated by a granal structure in response to regulation by a trans-thylakoid pH gradient, (6) delaying the premature degradation of D1 and D2 reaction-centre protein(s) in PSII by harbouring photoinactived PSIIs in appressed granal domains, (7) enhancement of the rate of non-cyclic synthesis of adenosine triphosphate (ATP) as well as the regulation of non-cyclic vs. cyclic ATP synthesis, and (8) the potential increase of photosynthetic capacity for a given composition of chloroplast constituents in full sunlight, concomitantly with enhancement of photochemical efficiency in canopy shade. Hence chloroplast ultrastructure and function are intimately intertwined.
Collapse
Affiliation(s)
- Wah Soon Chow
- Photobioenergetics Group, Research School of Biological Sciences, GPO Box 475, Canberra, ACT 2601, Australia.
| | | | | | | |
Collapse
|
50
|
Yang MT, Chen SL, Lin CY, Chen YM. Chilling stress suppresses chloroplast development and nuclear gene expression in leaves of mung bean seedlings. PLANTA 2005; 221:374-385. [PMID: 15599759 DOI: 10.1007/s00425-004-1451-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2004] [Accepted: 11/10/2004] [Indexed: 05/24/2023]
Abstract
Etiolated leaves of 28 degrees C-dark-grown mung bean (Vigna radiata L. cv. 2937) seedlings fail to turn green after being shifted to a light and cold environment. At the visible phenotypic level, incapability of leaf greening is the only failure event for the de-etiolation of mung bean seedlings at low temperature. Ultrastructural studies revealed that chloroplast development was completely suppressed by chilling treatment. A cDNA library originating from 28 degrees C-light-grown seedling leaves was constructed for screening cold-suppressed (cos) genes. Thirteen full-length cDNA clones were obtained, with 12 clones encoding chloroplast proteins, which, according to their known physiological functions, were important for chloroplast development and photosynthesis. Another cos cDNA encodes CYP90A2, which is a cytochrome P450 protein involved in the biosynthesis of brassinosteroid hormones. All cos genes are light-regulated at normal temperature. The influence of chilling stress on cos expression was examined in 10 degrees C-light- and 10 degrees C-dark-grown etiolated seedlings, and in 10 degrees C-light-grown green plants. The data show that cos expression in these three treatments is severely suppressed. This suppression is controlled at the transcriptional level, as demonstrated by nuclear runoff experiments, and is reversible because cos mRNAs accumulate again after the cold-treated plants have been transferred to 28 degrees C.
Collapse
Affiliation(s)
- Ming-Tzong Yang
- Institute of Plant Biology, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd, Taipei, 106, Taiwan (ROC)
| | | | | | | |
Collapse
|