1
|
Kato Y, Kuroda H, Ozawa SI, Saito K, Dogra V, Scholz M, Zhang G, de Vitry C, Ishikita H, Kim C, Hippler M, Takahashi Y, Sakamoto W. Characterization of tryptophan oxidation affecting D1 degradation by FtsH in the photosystem II quality control of chloroplasts. eLife 2023; 12:RP88822. [PMID: 37986577 PMCID: PMC10665015 DOI: 10.7554/elife.88822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2023] Open
Abstract
Photosynthesis is one of the most important reactions for sustaining our environment. Photosystem II (PSII) is the initial site of photosynthetic electron transfer by water oxidation. Light in excess, however, causes the simultaneous production of reactive oxygen species (ROS), leading to photo-oxidative damage in PSII. To maintain photosynthetic activity, the PSII reaction center protein D1, which is the primary target of unavoidable photo-oxidative damage, is efficiently degraded by FtsH protease. In PSII subunits, photo-oxidative modifications of several amino acids such as Trp have been indeed documented, whereas the linkage between such modifications and D1 degradation remains elusive. Here, we show that an oxidative post-translational modification of Trp residue at the N-terminal tail of D1 is correlated with D1 degradation by FtsH during high-light stress. We revealed that Arabidopsis mutant lacking FtsH2 had increased levels of oxidative Trp residues in D1, among which an N-terminal Trp-14 was distinctively localized in the stromal side. Further characterization of Trp-14 using chloroplast transformation in Chlamydomonas indicated that substitution of D1 Trp-14 to Phe, mimicking Trp oxidation enhanced FtsH-mediated D1 degradation under high light, although the substitution did not affect protein stability and PSII activity. Molecular dynamics simulation of PSII implies that both Trp-14 oxidation and Phe substitution cause fluctuation of D1 N-terminal tail. Furthermore, Trp-14 to Phe modification appeared to have an additive effect in the interaction between FtsH and PSII core in vivo. Together, our results suggest that the Trp oxidation at its N-terminus of D1 may be one of the key oxidations in the PSII repair, leading to processive degradation by FtsH.
Collapse
Affiliation(s)
- Yusuke Kato
- Institute of Plant Science and Resources (IPSR), Okayama UniversityOkayamaJapan
- Faculty of Agriculture, Setsunan UniversityOsakaJapan
| | - Hiroshi Kuroda
- Research Institute for Interdisciplinary Science, Okayama UniversityOkayamaJapan
| | - Shin-Ichiro Ozawa
- Institute of Plant Science and Resources (IPSR), Okayama UniversityOkayamaJapan
- Research Institute for Interdisciplinary Science, Okayama UniversityOkayamaJapan
| | - Keisuke Saito
- Research Center for Advanced Science and Technology, The University of TokyoTokyoJapan
| | - Vivek Dogra
- Shanghai Center for Plant Stress Biology, Center for Excellence in Molecular Plant Sciences, Chinese Academy of SciencesShanghaiChina
- Biotechnology Division, CSIR-Institute of Himalayan Bioresource TechnologyPalampurIndia
| | - Martin Scholz
- Institute of Plant Biology and Biotechnology, University of MünsterMünsterGermany
| | - Guoxian Zhang
- Institute of Plant Science and Resources (IPSR), Okayama UniversityOkayamaJapan
| | - Catherine de Vitry
- Institut de Biologie Physico-Chimique, Unité Mixte de Recherche 7141, Centre National de la Recherche Scientifique and Sorbonne Université Pierre et Marie CurieParisFrance
| | - Hiroshi Ishikita
- Research Center for Advanced Science and Technology, The University of TokyoTokyoJapan
| | - Chanhong Kim
- Shanghai Center for Plant Stress Biology, Center for Excellence in Molecular Plant Sciences, Chinese Academy of SciencesShanghaiChina
| | - Michael Hippler
- Institute of Plant Science and Resources (IPSR), Okayama UniversityOkayamaJapan
- Institute of Plant Biology and Biotechnology, University of MünsterMünsterGermany
| | - Yuichiro Takahashi
- Research Institute for Interdisciplinary Science, Okayama UniversityOkayamaJapan
| | - Wataru Sakamoto
- Institute of Plant Science and Resources (IPSR), Okayama UniversityOkayamaJapan
| |
Collapse
|
2
|
Lei Y, Li B, Wang X, Wei J, Wang P, Zhao J, Yu F, Qi Y. Chloroplast SRP54 and FtsH protease coordinate thylakoid membrane-associated proteostasis in Arabidopsis. PLANT PHYSIOLOGY 2023; 192:2318-2335. [PMID: 36994815 PMCID: PMC10315307 DOI: 10.1093/plphys/kiad199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 02/24/2023] [Accepted: 03/01/2023] [Indexed: 06/19/2023]
Abstract
Thylakoid membrane protein quality control (PQC), which requires the coordination of membrane protein translocation and degradation of unassembled proteins, determines chloroplast development during de-etiolation. Despite numerous efforts, the regulation of this process in land plants is largely unknown. Here, we report the isolation and characterization of pale green Arabidopsis4 (pga4) mutants in Arabidopsis (Arabidopsis thaliana) with defects in chloroplast development during de-etiolation. Map-based cloning and complementation assays confirmed that PGA4 encodes the chloroplast Signal Recognition Particle 54 kDa (cpSRP54) protein. A heterogeneous Light-Harvesting Chlorophyll a/b Binding-Green Fluorescent Protein (LhcB2-GFP) fusion protein was generated as an indicative reporter for cpSRP54-mediated thylakoid translocation. LhcB2-GFP was dysfunctional and degraded to a short-form dLhcB2-GFP during de-etiolation through an N-terminal degradation initiated on thylakoid membranes. Further biochemical and genetic evidence demonstrated that the degradation of LhcB2-GFP to dLhcB2-GFP was disrupted in pga4 and yellow variegated2 (var2) mutants caused by mutations in the Filamentous Temperature-Sensitive H2 (VAR2/AtFtsH2) subunit of thylakoid FtsH. The yeast two-hybrid assay showed that the N-terminus of LhcB2-GFP interacts with the protease domain of VAR2/AtFtsH2. Moreover, the over-accumulated LhcB2-GFP in pga4 and var2 formed protein aggregates, which were insoluble in mild nonionic detergents. Genetically, cpSRP54 is a suppressor locus for the leaf variegation phenotype of var2. Together, these results demonstrate the coordination of cpSRP54 and thylakoid FtsH in maintaining thylakoid membrane PQC during the assembly of photosynthetic complexes and provide a trackable substrate and product for monitoring cpSRP54-dependent protein translocation and FtsH-dependent protein degradation.
Collapse
Affiliation(s)
- Yang Lei
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Bilang Li
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Xiaomin Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Junyou Wei
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Peiyi Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Jun Zhao
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Fei Yu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Yafei Qi
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| |
Collapse
|
3
|
Wang F, Dischinger K, Westrich LD, Meindl I, Egidi F, Trösch R, Sommer F, Johnson X, Schroda M, Nickelsen J, Willmund F, Vallon O, Bohne AV. One-helix protein 2 is not required for the synthesis of photosystem II subunit D1 in Chlamydomonas. PLANT PHYSIOLOGY 2023; 191:1612-1633. [PMID: 36649171 PMCID: PMC10022639 DOI: 10.1093/plphys/kiad015] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 12/13/2022] [Indexed: 06/17/2023]
Abstract
In land plants and cyanobacteria, co-translational association of chlorophyll (Chl) to the nascent D1 polypeptide, a reaction center protein of photosystem II (PSII), requires a Chl binding complex consisting of a short-chain dehydrogenase (high chlorophyll fluorescence 244 [HCF244]/uncharacterized protein 39 [Ycf39]) and one-helix proteins (OHP1 and OHP2 in chloroplasts) of the light-harvesting antenna complex superfamily. Here, we show that an ohp2 mutant of the green alga Chlamydomonas (Chlamydomonas reinhardtii) fails to accumulate core PSII subunits, in particular D1 (encoded by the psbA mRNA). Extragenic suppressors arose at high frequency, suggesting the existence of another route for Chl association to PSII. The ohp2 mutant was complemented by the Arabidopsis (Arabidopsis thaliana) ortholog. In contrast to land plants, where psbA translation is prevented in the absence of OHP2, ribosome profiling experiments showed that the Chlamydomonas mutant translates the psbA transcript over its full length. Pulse labeling suggested that D1 is degraded during or immediately after translation. The translation of other PSII subunits was affected by assembly-controlled translational regulation. Proteomics showed that HCF244, a translation factor which associates with and is stabilized by OHP2 in land plants, still partly accumulates in the Chlamydomonas ohp2 mutant, explaining the persistence of psbA translation. Several Chl biosynthesis enzymes overaccumulate in the mutant membranes. Partial inactivation of a D1-degrading protease restored a low level of PSII activity in an ohp2 background, but not photoautotrophy. Taken together, our data suggest that OHP2 is not required for psbA translation in Chlamydomonas, but is necessary for D1 stabilization.
Collapse
Affiliation(s)
- Fei Wang
- Molecular Plant Sciences, LMU Munich, Planegg-Martinsried 82152, Germany
- UMR 7141, Centre National de la Recherche Scientifique/Sorbonne Université, Institut de Biologie Physico-Chimique, Paris 75005, France
- College of Life Sciences, Northwest University, Xi'an 710069, China
| | | | - Lisa Désirée Westrich
- Molecular Genetics of Eukaryotes, University of Kaiserslautern, 67663 Kaiserslautern, Germany
| | - Irene Meindl
- Molecular Plant Sciences, LMU Munich, Planegg-Martinsried 82152, Germany
| | - Felix Egidi
- Molecular Plant Sciences, LMU Munich, Planegg-Martinsried 82152, Germany
| | - Raphael Trösch
- Molecular Genetics of Eukaryotes, University of Kaiserslautern, 67663 Kaiserslautern, Germany
| | - Frederik Sommer
- Molecular Biotechnology and Systems Biology, University of Kaiserslautern, 67663 Kaiserslautern, Germany
| | - Xenie Johnson
- UMR 7141, Centre National de la Recherche Scientifique/Sorbonne Université, Institut de Biologie Physico-Chimique, Paris 75005, France
| | - Michael Schroda
- Molecular Biotechnology and Systems Biology, University of Kaiserslautern, 67663 Kaiserslautern, Germany
| | - Joerg Nickelsen
- Molecular Plant Sciences, LMU Munich, Planegg-Martinsried 82152, Germany
| | - Felix Willmund
- Molecular Genetics of Eukaryotes, University of Kaiserslautern, 67663 Kaiserslautern, Germany
| | - Olivier Vallon
- UMR 7141, Centre National de la Recherche Scientifique/Sorbonne Université, Institut de Biologie Physico-Chimique, Paris 75005, France
| | | |
Collapse
|
4
|
Yue X, Ke X, Shi Y, Li Y, Zhang C, Wang Y, Hou X. Chloroplast inner envelope protein FtsH11 is involved in the adjustment of assembly of chloroplast ATP synthase under heat stress. PLANT, CELL & ENVIRONMENT 2023; 46:850-864. [PMID: 36573466 DOI: 10.1111/pce.14525] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 12/08/2022] [Accepted: 12/11/2022] [Indexed: 06/17/2023]
Abstract
The maintenance of a proton gradient across the thylakoid membrane is an integral aspect of photosynthesis that is mainly established by the splitting of water molecules in photosystem II and plastoquinol oxidation at the cytochrome complex, and it is necessary for the generation of ATP in the last step of photophosphorylation. Although environmental stresses, such as high temperatures, are known to disrupt this fundamental process, only a few studies have explored the molecular mechanisms underlying proton gradient regulation during stress. The present study identified a heat-sensitive mutant that displays aberrant photosynthesis at high temperatures. This mutation was mapped to AtFtsH11, which encodes an ATP-dependent AAA-family metalloprotease. We showed that AtFtsH11 localizes to the chloroplast inner envelope membrane and is capable of degrading the ATP synthase assembly factor BFA3 under heat stress. We posit that this function limits the amount of ATP synthase integrated into the thylakoid membrane to regulate proton efflux from the lumen to the stroma. Our data also suggest that AtFtsH11 is critical in stabilizing photosystem II and cytochrome complexes at high temperatures, and additional studies can further elucidate the specific molecular functions of this critical regulator of photosynthetic thermotolerance.
Collapse
Affiliation(s)
- Xiaohong Yue
- State Key Laboratory of Hybrid Rice, Hubei Hongshan Laboratory, College of Life Sciences, Wuhan University, Wuhan, China
| | - Xiangsheng Ke
- State Key Laboratory of Hybrid Rice, Hubei Hongshan Laboratory, College of Life Sciences, Wuhan University, Wuhan, China
| | - Yafei Shi
- State Key Laboratory of Hybrid Rice, Hubei Hongshan Laboratory, College of Life Sciences, Wuhan University, Wuhan, China
| | - Yangsheng Li
- State Key Laboratory of Hybrid Rice, Hubei Hongshan Laboratory, College of Life Sciences, Wuhan University, Wuhan, China
| | - Chenhao Zhang
- State Key Laboratory of Hybrid Rice, Hubei Hongshan Laboratory, College of Life Sciences, Wuhan University, Wuhan, China
| | - Yetao Wang
- State Key Laboratory of Hybrid Rice, Hubei Hongshan Laboratory, College of Life Sciences, Wuhan University, Wuhan, China
| | - Xin Hou
- State Key Laboratory of Hybrid Rice, Hubei Hongshan Laboratory, College of Life Sciences, Wuhan University, Wuhan, China
| |
Collapse
|
5
|
Fu W, Cui Z, Guo J, Cui X, Han G, Zhu Y, Hu J, Gao X, Li Y, Xu M, Fu A, Wang F. Immunophilin CYN28 is required for accumulation of photosystem II and thylakoid FtsH protease in Chlamydomonas. PLANT PHYSIOLOGY 2023; 191:1002-1016. [PMID: 36417279 PMCID: PMC9922407 DOI: 10.1093/plphys/kiac524] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 11/17/2022] [Indexed: 06/16/2023]
Abstract
Excess light causes severe photodamage to photosystem II (PSII) where the primary charge separation for electron transfer takes place. Dissection of mechanisms underlying the PSII maintenance and repair cycle in green algae promotes the usage of genetic engineering and synthetic biology to improve photosynthesis and biomass production. In this study, we systematically analyzed the high light (HL) responsive immunophilin genes in Chlamydomonas (Chlamydomonas reinhardtii) and identified one chloroplast lumen-localized immunophilin, CYN28, as an essential player in HL tolerance. Lack of CYN28 caused HL hypersensitivity, severely reduced accumulation of PSII supercomplexes and compromised PSII repair in cyn28. The thylakoid FtsH (filamentation temperature-sensitive H) is an essential AAA family metalloprotease involved in the degradation of photodamaged D1 during the PSII repair cycle and was identified as one potential target of CYN28. In the cyn28 mutant, the thylakoid FtsH undergoes inefficient turnover under HL conditions. The CYN28-FtsH1/2 interaction relies on the FtsH N-terminal proline residues and is strengthened particularly under HL. Further analyses demonstrated CYN28 displays peptidyl-prolyl isomerase (PPIase) activity, which is necessary for its physiological function. Taken together, we propose that immunophilin CYN28 participates in PSII maintenance and regulates the homeostasis of FtsH under HL stress via its PPIase activity.
Collapse
Affiliation(s)
- Weihan Fu
- Chinese Education Ministry's Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| | - Zheng Cui
- Chinese Education Ministry's Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| | - Jia Guo
- Chinese Education Ministry's Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| | - Xiayu Cui
- Chinese Education Ministry's Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| | - Guomao Han
- Chinese Education Ministry's Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| | - Yunpeng Zhu
- Chinese Education Ministry's Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| | - Jinju Hu
- Chinese Education Ministry's Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| | - Xiaoling Gao
- Chinese Education Ministry's Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| | - Yeqing Li
- Chinese Education Ministry's Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| | - Min Xu
- Chinese Education Ministry's Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| | - Aigen Fu
- Chinese Education Ministry's Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| | - Fei Wang
- Chinese Education Ministry's Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| |
Collapse
|
6
|
Calderon RH, de Vitry C, Wollman FA, Niyogi KK. Rubredoxin 1 promotes the proper folding of D1 and is not required for heme b 559 assembly in Chlamydomonas photosystem II. J Biol Chem 2023; 299:102968. [PMID: 36736898 PMCID: PMC9986647 DOI: 10.1016/j.jbc.2023.102968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 01/20/2023] [Accepted: 01/23/2023] [Indexed: 02/04/2023] Open
Abstract
Photosystem II (PSII), the water:plastoquinone oxidoreductase of oxygenic photosynthesis, contains a heme b559 iron whose axial ligands are provided by histidine residues from the α (PsbE) and β (PsbF) subunits. PSII assembly depends on accessory proteins that facilitate the step-wise association of its protein and pigment components into a functional complex, a process that is challenging to study due to the low accumulation of assembly intermediates. Here, we examined the putative role of the iron[1Fe-0S]-containing protein rubredoxin 1 (RBD1) as an assembly factor for cytochrome b559, using the RBD1-lacking 2pac mutant from Chlamydomonas reinhardtii, in which the accumulation of PSII was rescued by the inactivation of the thylakoid membrane FtsH protease. To this end, we constructed the double mutant 2pac ftsh1-1, which harbored PSII dimers that sustained its photoautotrophic growth. We purified PSII from the 2pac ftsh1-1 background and found that α and β cytochrome b559 subunits are still present and coordinate heme b559 as in the WT. Interestingly, immunoblot analysis of dark- and low light-grown 2pac ftsh1-1 showed the accumulation of a 23-kDa fragment of the D1 protein, a marker typically associated with structural changes resulting from photodamage of PSII. Its cleavage occurs in the vicinity of a nonheme iron which binds to PSII on its electron acceptor side. Altogether, our findings demonstrate that RBD1 is not required for heme b559 assembly and point to a role for RBD1 in promoting the proper folding of D1, possibly via delivery or reduction of the nonheme iron during PSII assembly.
Collapse
Affiliation(s)
- Robert H Calderon
- Department of Plant and Microbial Biology, University of California, Berkeley, California, USA; Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, Umeå, Sweden.
| | - Catherine de Vitry
- Institut de Biologie Physico-Chimique, Unité Mixte de Recherche 7141, Centre National de la Recherche Scientifique and Sorbonne Université, Institut de Biologie Physico-Chimique, Paris, France
| | - Francis-André Wollman
- Institut de Biologie Physico-Chimique, Unité Mixte de Recherche 7141, Centre National de la Recherche Scientifique and Sorbonne Université, Institut de Biologie Physico-Chimique, Paris, France
| | - Krishna K Niyogi
- Department of Plant and Microbial Biology, University of California, Berkeley, California, USA; Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA; Howard Hughes Medical Institute, University of California, Berkeley, California, USA
| |
Collapse
|
7
|
Gao LL, Hong ZH, Wang Y, Wu GZ. Chloroplast proteostasis: A story of birth, life, and death. PLANT COMMUNICATIONS 2023; 4:100424. [PMID: 35964157 PMCID: PMC9860172 DOI: 10.1016/j.xplc.2022.100424] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 08/02/2022] [Accepted: 08/10/2022] [Indexed: 06/02/2023]
Abstract
Protein homeostasis (proteostasis) is a dynamic balance of protein synthesis and degradation. Because of the endosymbiotic origin of chloroplasts and the massive transfer of their genetic information to the nucleus of the host cell, many protein complexes in the chloroplasts are constituted from subunits encoded by both genomes. Hence, the proper function of chloroplasts relies on the coordinated expression of chloroplast- and nucleus-encoded genes. The biogenesis and maintenance of chloroplast proteostasis are dependent on synthesis of chloroplast-encoded proteins, import of nucleus-encoded chloroplast proteins from the cytosol, and clearance of damaged or otherwise undesired "old" proteins. This review focuses on the regulation of chloroplast proteostasis, its interaction with proteostasis of the cytosol, and its retrograde control over nuclear gene expression. We also discuss significant issues and perspectives for future studies and potential applications for improving the photosynthetic performance and stress tolerance of crops.
Collapse
Affiliation(s)
- Lin-Lin Gao
- Shanghai Collaborative Innovation Center of Agri-Seeds, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China; Joint Center for Single Cell Biology, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
| | - Zheng-Hui Hong
- Shanghai Collaborative Innovation Center of Agri-Seeds, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China; Joint Center for Single Cell Biology, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
| | - Yinsong Wang
- Shanghai Collaborative Innovation Center of Agri-Seeds, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China; Joint Center for Single Cell Biology, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
| | - Guo-Zhang Wu
- Shanghai Collaborative Innovation Center of Agri-Seeds, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China; Joint Center for Single Cell Biology, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China.
| |
Collapse
|
8
|
Ariga T, Sakuraba Y, Zhuo M, Yang M, Yanagisawa S. The Arabidopsis NLP7-HB52/54-VAR2 pathway modulates energy utilization in diverse light and nitrogen conditions. Curr Biol 2022; 32:5344-5353.e6. [PMID: 36332616 DOI: 10.1016/j.cub.2022.10.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 09/22/2022] [Accepted: 10/13/2022] [Indexed: 11/06/2022]
Abstract
In plants, nitrate is the dominant nitrogen (N) source and a critical nutrient signal regulating various physiological and developmental processes.1,2,3,4 Nitrate-responsive gene regulatory networks are widely believed to control growth, development, and life cycle in addition to N acquisition and utilization,1,2,3,4 and NIN-LIKE PROTEIN (NLP) transcriptional activators have been identified as the master regulators governing the networks.5,6,7 However, it remains to be elucidated how nitrate signaling regulates respective physiological and developmental processes. Here, we have identified a new nitrate-activated transcriptional cascade involved in chloroplast development and the maintenance of chloroplast function in Arabidopsis. This cascade consisting of NLP7 and two homeodomain-leucine zipper (HD-Zip) class I transcription factors, HOMEOBOX PROTEIN52 (HB52) and HB54,8,9 was responsible for nitrate- and light-dependent expression of VAR2 encoding the FtsH2 subunit of the chloroplast FtsH protease involved in the quality control of photodamaged thylakoid membrane proteins.10,11 Consistently, the nitrate-activated NLP7-HB52/54-VAR2 pathway underpinned photosynthetic light energy utilization, especially in high light environments. Furthermore, genetically enhancing the NLP7-HB52/54-VAR2 pathway resulted in improved light energy utilization under high light and low N conditions, a superior agronomic trait. These findings shed light on a new role of nitrate signaling and a novel mechanism for integrating information on N nutrient and light environments, providing a hint for enhancing the light energy utilization of plants in low N environments.
Collapse
Affiliation(s)
- Takuto Ariga
- Agro-Biotechnology Research Center, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan
| | - Yasuhito Sakuraba
- Agro-Biotechnology Research Center, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan
| | - Mengna Zhuo
- Agro-Biotechnology Research Center, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan
| | - Mailun Yang
- Agro-Biotechnology Research Center, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan
| | - Shuichi Yanagisawa
- Agro-Biotechnology Research Center, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan.
| |
Collapse
|
9
|
Sakuraba Y. Molecular basis of nitrogen starvation-induced leaf senescence. FRONTIERS IN PLANT SCIENCE 2022; 13:1013304. [PMID: 36212285 PMCID: PMC9538721 DOI: 10.3389/fpls.2022.1013304] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Accepted: 09/08/2022] [Indexed: 06/01/2023]
Abstract
Nitrogen (N), a macronutrient, is often a limiting factor in plant growth, development, and productivity. To adapt to N-deficient environments, plants have developed elaborate N starvation responses. Under N-deficient conditions, older leaves exhibit yellowing, owing to the degradation of proteins and chlorophyll pigments in chloroplasts and subsequent N remobilization from older leaves to younger leaves and developing organs to sustain plant growth and productivity. In recent years, numerous studies have been conducted on N starvation-induced leaf senescence as one of the representative plant responses to N deficiency, revealing that leaf senescence induced by N deficiency is highly complex and intricately regulated at different levels, including transcriptional, post-transcriptional, post-translational and metabolic levels, by multiple genes and proteins. This review summarizes the current knowledge of the molecular mechanisms associated with N starvation-induced leaf senescence.
Collapse
|
10
|
Chloroplast envelope ATPase PGA1/AtFtsH12 is required for chloroplast protein accumulation and cytosol-chloroplast protein homeostasis in Arabidopsis. J Biol Chem 2022; 298:102489. [PMID: 36113581 PMCID: PMC9574505 DOI: 10.1016/j.jbc.2022.102489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 09/05/2022] [Accepted: 09/06/2022] [Indexed: 11/20/2022] Open
Abstract
The establishment of photosynthetic protein complexes during chloroplast development requires the influx of a large number of chloroplast proteins that are encoded by the nuclear genome, which is critical for cytosol and chloroplast protein homeostasis and chloroplast development. However, the mechanisms regulating this process are still not well understood in higher plants. Here, we report the isolation and characterization of the pale green Arabidopsis pga1-1 mutant, which is defective in chloroplast development and chloroplast protein accumulation. Using genetic and biochemical evidence, we reveal that PGA1 encodes AtFtsH12, a chloroplast envelope-localized protein of the FtsH family proteins. We determined a G703R mutation in the GAD motif of the conserved ATPase domain renders the pga1-1 a viable hypomorphic allele of the essential gene AtFtsH12. In de-etiolation assays, we showed that the accumulation of photosynthetic proteins and the expression of photosynthetic genes were impaired in pga1-1. Using the FNRctp-GFP and pTAC2-GFP reporters, we demonstrated that AtFtsH12 was required for the accumulation of chloroplast proteins in vivo. Interestingly, we identified an increase in expression of the mutant AtFtsH12 gene in pga1-1, suggesting a feedback regulation. Moreover, we found that cytosolic and chloroplast proteostasis responses were triggered in pga1-1. Together, taking advantage of the novel pga1-1 mutant, we demonstrate the function of AtFtsH12 in chloroplast protein homeostasis and chloroplast development.
Collapse
|
11
|
Wang X, Li Q, Zhang Y, Pan M, Wang R, Sun Y, An L, Liu X, Yu F, Qi Y. VAR2/AtFtsH2 and EVR2/BCM1/CBD1 synergistically regulate the accumulation of PSII reaction centre D1 protein during de-etiolation in Arabidopsis. PLANT, CELL & ENVIRONMENT 2022; 45:2395-2409. [PMID: 35610189 DOI: 10.1111/pce.14368] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 04/26/2022] [Accepted: 04/29/2022] [Indexed: 06/15/2023]
Abstract
Thylakoid FtsH complex participates in PSII repair cycle during high light-induced photoinhibition. The Arabidopsis yellow variegated2 (var2) mutants are defective in the VAR2/AtFtsH2 subunit of thylakoid FtsH complex. Taking advantage of the var2 leaf variegation phenotype, dissections of genetic enhancer loci have yielded novel paradigms in understanding functions of thylakoid FtsH complex. Here, we report the isolation of a new var2 enhancer, enhancer of variegation2-1 (evr2-1). We confirmed that EVR2 encodes a chloroplast protein that was known as BALANCE OF CHLOROPHYLL METABOLISM 1 (BCM1), or CHLOROPHYLL BIOSYNTHETIC DEFECT 1 (CBD1). We showed that EVR2/BCM1/CBD1 was involved in the oligomerization of photosystem I complexes. Genetic assays indicated that general defects in chlorophyll biosynthesis and the accumulation of photosynthetic complexes do not necessarily enhance var2 leaf variegation. In addition, we found that VAR2/AtFtsH2 is required for the accumulation of photosynthetic proteins during de-etiolation. Moreover, we identified PSII core proteins D1 and PsbC as potential EVR2-associated proteins using Co-IP/MS. Furthermore, the accumulation of D1 protein was greatly compromised in the var2-5 evr2-1 double mutant during de-etiolation. Together, our findings reveal a functional link between VAR2/AtFtsH2 and EVR2/BCM1/CBD1 in regulating chloroplast development and the accumulation of PSII reaction centre D1 protein during de-etiolation.
Collapse
Affiliation(s)
- Xiaomin Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, P.R. China
| | - Qinglong Li
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, P.R. China
| | - Yalin Zhang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, P.R. China
| | - Mi Pan
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, P.R. China
| | - Ruijuan Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, P.R. China
| | - Yifan Sun
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, P.R. China
| | - Lijun An
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, P.R. China
| | - Xiayan Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, P.R. China
| | - Fei Yu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, P.R. China
| | - Yafei Qi
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, P.R. China
| |
Collapse
|
12
|
Chloroplasts Protein Quality Control and Turnover: A Multitude of Mechanisms. Int J Mol Sci 2022; 23:ijms23147760. [PMID: 35887108 PMCID: PMC9319218 DOI: 10.3390/ijms23147760] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 07/11/2022] [Accepted: 07/12/2022] [Indexed: 11/16/2022] Open
Abstract
As the organelle of photosynthesis and other important metabolic pathways, chloroplasts contain up to 70% of leaf proteins with uniquely complex processes in synthesis, import, assembly, and turnover. Maintaining functional protein homeostasis in chloroplasts is vitally important for the fitness and survival of plants. Research over the past several decades has revealed a multitude of mechanisms that play important roles in chloroplast protein quality control and turnover under normal and stress conditions. These mechanisms include: (i) endosymbiotically-derived proteases and associated proteins that play a vital role in maintaining protein homeostasis inside the chloroplasts, (ii) the ubiquitin-dependent turnover of unimported chloroplast precursor proteins to prevent their accumulation in the cytosol, (iii) chloroplast-associated degradation of the chloroplast outer-membrane translocon proteins for the regulation of chloroplast protein import, (iv) chloroplast unfolded protein response triggered by accumulated unfolded and misfolded proteins inside the chloroplasts, and (v) vesicle-mediated degradation of chloroplast components in the vacuole. Here, we provide a comprehensive review of these diverse mechanisms of chloroplast protein quality control and turnover and discuss important questions that remain to be addressed in order to better understand and improve important chloroplast functions.
Collapse
|
13
|
Enzymes degraded under high light maintain proteostasis by transcriptional regulation in Arabidopsis. Proc Natl Acad Sci U S A 2022; 119:e2121362119. [PMID: 35549553 PMCID: PMC9171785 DOI: 10.1073/pnas.2121362119] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Photoinhibitory high light stress in plants leads to increases in markers of protein degradation and transcriptional up-regulation of proteases and proteolytic machinery, but protein homeostasis (proteostasis) of most enzymes is largely maintained under high light, so we know little about the metabolic consequences of it beyond photosystem damage. We developed a technique to look for rapid protein turnover events in response to high light through 13C partial labeling and detailed peptide mass spectrometry. This analysis reveals a light-induced transcriptional program for nuclear-encoded genes, beyond the regulation of photosystem II, to replace key protein degradation targets in plants and ensure proteostasis under high light stress. Photoinhibitory high light stress in Arabidopsis leads to increases in markers of protein degradation and transcriptional up-regulation of proteases and proteolytic machinery, but proteostasis is largely maintained. We find significant increases in the in vivo degradation rate for specific molecular chaperones, nitrate reductase, glyceraldehyde-3 phosphate dehydrogenase, and phosphoglycerate kinase and other plastid, mitochondrial, peroxisomal, and cytosolic enzymes involved in redox shuttles. Coupled analysis of protein degradation rates, mRNA levels, and protein abundance reveal that 57% of the nuclear-encoded enzymes with higher degradation rates also had high light–induced transcriptional responses to maintain proteostasis. In contrast, plastid-encoded proteins with enhanced degradation rates showed decreased transcript abundances and must maintain protein abundance by other processes. This analysis reveals a light-induced transcriptional program for nuclear-encoded genes, beyond the regulation of the photosystem II (PSII) D1 subunit and the function of PSII, to replace key protein degradation targets in plants and ensure proteostasis under high light stress.
Collapse
|
14
|
Wen X, Yang Z, Ding S, Yang H, Zhang L, Lu C, Lu Q. Analysis of the changes of electron transfer and heterogeneity of photosystem II in Deg1-reduced Arabidopsis plants. PHOTOSYNTHESIS RESEARCH 2021; 150:159-177. [PMID: 33993381 DOI: 10.1007/s11120-021-00842-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 05/04/2021] [Indexed: 05/07/2023]
Abstract
Deg1 protease functions in protease and chaperone of PSII complex components, but few works were performed to study the effects of Deg1 on electron transport activities on the donor and acceptor side of PSII and its correlation with the photoprotection of PSII during photoinhibition. Therefore, we performed systematic and comprehensive investigations of electron transfers on the donor and acceptor sides of photosystem II (PSII) in the Deg1-reduced transgenic lines deg1-2 and deg1-4. Both the maximal quantum efficiency of PSII photochemistry (Fv/Fm) and the actual PSII efficiency (ΦPSII) decreased significantly in the transgenic plants. Increases in nonphotochemical quenching (NPQ) and the dissipated energy flux per reaction center (DI0/RC) were also shown in the transgenic plants. Along with the decreased D1, CP47, and CP43 content, these results suggested photoinhibition under growth light conditions in transgenic plants. Decreased Deg1 caused inhibition of electron transfer on the PSII reducing side, leading to a decline in the number of QB-reducing centers and accumulation of QB-nonreducing centers. The Tm of the Q band shifted from 5.7 °C in the wild-type plant to 10.4 °C and 14.2 °C in the deg1-2 and deg1-4 plants, respectively, indicating an increase in the stability of S2QA¯ in transgenic plants. PSIIα in the transgenic plants largely reduced, while PSIIβ and PSIIγ increased with the decline in the Deg1 levels in transgenic plants suggesting PSIIα centers gradually converted into PSIIβ and PSIIγ centers in the transgenic plants. Besides, the connectivity of PSIIα and PSIIβ was downregulated in transgenic plants. Our results reveal that downregulation of Deg1 protein levels induced photoinhibition in transgenic plants, leading to loss of PSII activities on both the donor and acceptor sides in transgenic plants. These results give a new insight into the regulation role of Deg1 in PSII electron transport.
Collapse
Affiliation(s)
- Xiaogang Wen
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, 100093, China
| | - Zhipan Yang
- 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
| | - Huixia Yang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Lixin Zhang
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, 85 Minglun Street, Kaifeng, 475001, China
| | - Congming Lu
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, 271018, China.
| | - Qingtao Lu
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.
| |
Collapse
|
15
|
Chen W, Zheng L, Dong J, Ge H, Huang X, Wang G, Huang C, Wang Y, Lu D, Xu W, Wang Y. A Systematic Survey of the Light/Dark-dependent Protein Degradation Events in a Model Cyanobacterium. Mol Cell Proteomics 2021; 20:100162. [PMID: 34655801 PMCID: PMC8603205 DOI: 10.1016/j.mcpro.2021.100162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 09/08/2021] [Accepted: 10/11/2021] [Indexed: 11/06/2022] Open
Abstract
Light is essential for photosynthetic organisms and is involved in the regulation of protein synthesis and degradation. The significance of light-regulated protein degradation is exemplified by the well-established light-induced degradation and repair of the photosystem II reaction center D1 protein in higher plants and cyanobacteria. However, systematic studies of light-regulated protein degradation events in photosynthetic organisms are lacking. Thus, we conducted a large-scale survey of protein degradation under light or dark conditions in the model cyanobacterium Synechocystis sp. PCC 6803 (hereafter referred to as Synechocystis) using the isobaric labeling-based quantitative proteomics technique. The results revealed that 79 proteins showed light-regulated degradation, including proteins involved in photosystem II structure or function, quinone binding, and NADH dehydrogenase. Among these, 25 proteins were strongly dependent on light for degradation. Moreover, the light-dependent degradation of several proteins was sensitive to photosynthetic electron transport inhibitors (DCMU and DBMIB), suggesting that they are influenced by the redox state of the plastoquinone (PQ) pool. Together, our study comprehensively cataloged light-regulated protein degradation events, and the results serve as an important resource for future studies aimed at understanding light-regulated processes and protein quality control mechanisms in cyanobacteria. Light-/dark-regulated protein degradation events in a model Cyanobacterium were identified. Seventy-nine proteins displayed light-regulated degradation. Thirty-one proteins displayed dark-regulated degradation. Multiple light-regulated protein degradation events were regulated by the redox state of the plastoquinone pool.
Collapse
Affiliation(s)
- Weiyang Chen
- State Key Laboratory of Molecular Developmental Biology, Innovation Academy for Seed Design, CAS, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Limin Zheng
- State Key Laboratory of Molecular Developmental Biology, Innovation Academy for Seed Design, CAS, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Jinghui Dong
- State Key Laboratory of Molecular Developmental Biology, Innovation Academy for Seed Design, CAS, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Haitao Ge
- State Key Laboratory of Molecular Developmental Biology, Innovation Academy for Seed Design, CAS, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Xiahe Huang
- State Key Laboratory of Molecular Developmental Biology, Innovation Academy for Seed Design, CAS, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Gaojie Wang
- State Key Laboratory of Molecular Developmental Biology, Innovation Academy for Seed Design, CAS, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Chengcheng Huang
- State Key Laboratory of Molecular Developmental Biology, Innovation Academy for Seed Design, CAS, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Yan Wang
- State Key Laboratory of Molecular Developmental Biology, Innovation Academy for Seed Design, CAS, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Dandan Lu
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, China
| | - Wu Xu
- Department of Chemistry, University of Louisiana at Lafayette, Lafayette, Louisiana, USA
| | - Yingchun Wang
- State Key Laboratory of Molecular Developmental Biology, Innovation Academy for Seed Design, CAS, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China.
| |
Collapse
|
16
|
Wu Q, Han T, Yang L, Wang Q, Zhao Y, Jiang D, Ruan X. The essential roles of OsFtsH2 in developing the chloroplast of rice. BMC PLANT BIOLOGY 2021; 21:445. [PMID: 34598671 PMCID: PMC8485545 DOI: 10.1186/s12870-021-03222-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 09/20/2021] [Indexed: 05/08/2023]
Abstract
BACKGROUND Filamentation temperature-sensitive H (FtsH) is an ATP-dependent zinc metalloprotease with ATPase activity, proteolysis activity and molecular chaperone-like activity. For now, a total of nine FtsH proteins have been encoded in rice, but their functions have not revealed in detail. In order to investigate the molecular mechanism of OsFtsH2 here, several osftsh2 knockout mutants were successfully generated by the CRISPR/Cas9 gene editing technology. RESULTS All the mutants exhibited a phenotype of striking albino leaf and could not survive through the stage of three leaves. OsFtsH2 was located in the chloroplast and preferentially expressed in green tissues. In addition, osftsh2 mutants could not form normal chloroplasts and had lost photosynthetic autotrophic capacity. RNA sequencing analysis indicated that many biological processes such as photosynthesis-related pathways and plant hormone signal transduction were significantly affected in osftsh2 mutants. CONCLUSIONS Overall, the results suggested OsFtsH2 to be essential for chloroplast development in rice.
Collapse
Affiliation(s)
- Qingfei Wu
- School of Biological and Chemical Engineering, NingboTech University, Ningbo, 315100, China
- Ningbo Research Institute, Zhejiang University, Ningbo, 315100, China
| | - Tiantian Han
- State Key Laboratory of Plant Genomics, National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Li Yang
- School of Biological and Chemical Engineering, NingboTech University, Ningbo, 315100, China
- Ningbo Research Institute, Zhejiang University, Ningbo, 315100, China
| | - Qiang Wang
- School of Biological and Chemical Engineering, NingboTech University, Ningbo, 315100, China.
- Ningbo Research Institute, Zhejiang University, Ningbo, 315100, China.
| | - Yingxian Zhao
- School of Biological and Chemical Engineering, NingboTech University, Ningbo, 315100, China
- Ningbo Research Institute, Zhejiang University, Ningbo, 315100, China
| | - Dean Jiang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Xiao Ruan
- School of Biological and Chemical Engineering, NingboTech University, Ningbo, 315100, China.
- Ningbo Research Institute, Zhejiang University, Ningbo, 315100, China.
| |
Collapse
|
17
|
Tian YN, Zhong RH, Wei JB, Luo HH, Eyal Y, Jin HL, Wu LJ, Liang KY, Li YM, Chen SZ, Zhang ZQ, Pang XQ. Arabidopsis CHLOROPHYLLASE 1 protects young leaves from long-term photodamage by facilitating FtsH-mediated D1 degradation in photosystem II repair. MOLECULAR PLANT 2021; 14:1149-1167. [PMID: 33857689 DOI: 10.1016/j.molp.2021.04.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 04/01/2021] [Accepted: 04/08/2021] [Indexed: 06/12/2023]
Abstract
The proteolytic degradation of the photodamaged D1 core subunit during the photosystem II (PSII) repair cycle is well understood, but chlorophyll turnover during D1 degradation remains unclear. Here, we report that Arabidopsis thaliana CHLOROPHYLLASE 1 (CLH1) plays important roles in the PSII repair process. The abundance of CLH1 and CLH2 peaks in young leaves and is induced by high-light exposure. Seedlings of clh1 single and clh1-1/2-2 double mutants display increased photoinhibition after long-term high-light exposure, whereas seedlings overexpressing CLH1 have enhanced light tolerance compared with the wild type. CLH1 is localized in the developing chloroplasts of young leaves and associates with the PSII-dismantling complexes RCC1 and RC47, with a preference for the latter upon exposure to high light. Furthermore, degradation of damaged D1 protein is retarded in young clh1-1/2-2 leaves after 18-h high-light exposure but is rescued by the addition of recombinant CLH1 in vitro. Moreover, overexpression of CLH1 in a variegated mutant (var2-2) that lacks thylakoid protease FtsH2, with which CLH1 interacts, suppresses the variegation and restores D1 degradation. A var2-2 clh1-1/2-2 triple mutant shows more severe variegation and seedling death. Taken together, these results establish CLH1 as a long-sought chlorophyll dephytylation enzyme that is involved in PSII repair and functions in long-term adaptation of young leaves to high-light exposure by facilitating FtsH-mediated D1 degradation.
Collapse
Affiliation(s)
- Ya-Nan Tian
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, South China Agricultural University, Guangzhou 510642, People's Republic of China; College of Life Sciences, South China Agricultural University, Guangzhou 510642, People's Republic of China
| | - Rui-Hao Zhong
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, South China Agricultural University, Guangzhou 510642, People's Republic of China; College of Life Sciences, South China Agricultural University, Guangzhou 510642, People's Republic of China
| | - Jun-Bin Wei
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, South China Agricultural University, Guangzhou 510642, People's Republic of China; College of Life Sciences, South China Agricultural University, Guangzhou 510642, People's Republic of China
| | - Hong-Hui Luo
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, South China Agricultural University, Guangzhou 510642, People's Republic of China; College of Horticulture, South China Agricultural University, Guangzhou 510642, People's Republic of China
| | - Yoram Eyal
- Institute of Plant Sciences, The Volcani Center, Agricultural Research Organization, Bet Dagan 50250, Israel
| | - Hong-Lei Jin
- Institute of Medical Plant Physiology and Ecology, School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou 510006, People's Republic of China
| | - La-Jie Wu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, South China Agricultural University, Guangzhou 510642, People's Republic of China; College of Life Sciences, South China Agricultural University, Guangzhou 510642, People's Republic of China
| | - Ke-Ying Liang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, South China Agricultural University, Guangzhou 510642, People's Republic of China; College of Life Sciences, South China Agricultural University, Guangzhou 510642, People's Republic of China
| | - Ying-Man Li
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, South China Agricultural University, Guangzhou 510642, People's Republic of China; College of Life Sciences, South China Agricultural University, Guangzhou 510642, People's Republic of China
| | - Shu-Zhen Chen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, South China Agricultural University, Guangzhou 510642, People's Republic of China; College of Life Sciences, South China Agricultural University, Guangzhou 510642, People's Republic of China
| | - Zhao-Qi Zhang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, South China Agricultural University, Guangzhou 510642, People's Republic of China; College of Horticulture, South China Agricultural University, Guangzhou 510642, People's Republic of China.
| | - Xue-Qun Pang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, South China Agricultural University, Guangzhou 510642, People's Republic of China; College of Life Sciences, South China Agricultural University, Guangzhou 510642, People's Republic of China.
| |
Collapse
|
18
|
Xiao JJ, Zhang RX, Khan A, Ul Haq S, Gai WX, Gong ZH. CaFtsH06, A Novel Filamentous Thermosensitive Protease Gene, Is Involved in Heat, Salt, and Drought Stress Tolerance of Pepper ( Capsicum annuum L.). Int J Mol Sci 2021; 22:ijms22136953. [PMID: 34203346 PMCID: PMC8268771 DOI: 10.3390/ijms22136953] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 06/23/2021] [Accepted: 06/23/2021] [Indexed: 11/29/2022] Open
Abstract
Harsh environmental factors have continuous negative effects on plant growth and development, leading to metabolic disruption and reduced plant productivity and quality. However, filamentation temperature-sensitive H protease (FtsH) plays a prominent role in helping plants to cope with these negative impacts. In the current study, we examined the transcriptional regulation of the CaFtsH06 gene in the R9 thermo-tolerant pepper (Capsicum annuum L.) line. The results of qRT-PCR revealed that CaFtsH06 expression was rapidly induced by abiotic stress treatments, including heat, salt, and drought. The CaFtsH06 protein was localized to the mitochondria and cell membrane. Additionally, silencing CaFtsH06 increased the accumulation of malonaldehyde content, conductivity, hydrogen peroxide (H2O2) content, and the activity levels of superoxide dismutase and superoxide (·O2−), while total chlorophyll content decreased under these abiotic stresses. Furthermore, CaFtsH06 ectopic expression enhanced tolerance to heat, salt, and drought stresses, thus decreasing malondialdehyde, proline, H2O2, and ·O2− contents while superoxide dismutase activity and total chlorophyll content were increased in transgenic Arabidopsis. Similarly, the expression levels of other defense-related genes were much higher in the transgenic ectopic expression lines than WT plants. These results suggest that CaFtsH06 confers abiotic stress tolerance in peppers by interfering with the physiological indices through reducing the accumulation of reactive oxygen species, inducing the activities of stress-related enzymes and regulating the transcription of defense-related genes, among other mechanisms. The results of this study suggest that CaFtsH06 plays a very crucial role in the defense mechanisms of pepper plants to unfavorable environmental conditions and its regulatory network with other CaFtsH genes should be examined across variable environments.
Collapse
Affiliation(s)
- Jing-Jing Xiao
- College of Horticulture, Northwest A&F University, Yangling, Xianyang 712100, China
| | - Rui-Xing Zhang
- College of Horticulture, Northwest A&F University, Yangling, Xianyang 712100, China
| | - Abid Khan
- Department of Horticulture, The University of Haripur, Haripur 22620, Pakistan
| | - Saeed Ul Haq
- College of Horticulture, Northwest A&F University, Yangling, Xianyang 712100, China
- Department of Horticulture, University of Agriculture Peshawar, Peshawar 25120, Pakistan
| | - Wen-Xian Gai
- College of Horticulture, Northwest A&F University, Yangling, Xianyang 712100, China
| | - Zhen-Hui Gong
- College of Horticulture, Northwest A&F University, Yangling, Xianyang 712100, China
| |
Collapse
|
19
|
Xu K, Zhu J, Zhai H, Wu H, Gao Y, Li Y, Zhu X, Xia Z. A critical role of PvFtsH2 in the degradation of photodamaged D1 protein in common bean. HORTICULTURE RESEARCH 2021; 8:126. [PMID: 34059658 PMCID: PMC8167180 DOI: 10.1038/s41438-021-00554-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 03/13/2021] [Accepted: 03/22/2021] [Indexed: 06/12/2023]
Abstract
Light is required for initiating chloroplast biogenesis and photosynthesis; however, the photosystem II reaction center (PSII RC) can be photodamaged. In this study, we characterized pvsl1, a seedling-lethal mutant of Phaseolus vulgaris. This mutant showed lethality when exposed to sunlight irradiation and a yellow-green leaf phenotype when grown in a growth chamber under low-light conditions. We developed 124 insertion/deletion (INDEL) markers based on resequencing data of Dalong1 and PI60234, two local Chinese common bean cultivars, for genetic mapping. We identified Phvul.002G190900, which encodes the PvFtsH2 protein, as the candidate gene for this pvsl1 mutation through fine-mapping and functional analysis. A single-base deletion occurred in the coding region of Phvul.002G190900 in the pvsl1 mutant, resulting in a frameshift mutation and a truncated protein lacking the Zn2+ metalloprotease domain. Suppressed expression of Phvul.002G190900 at the transcriptional level was detected, while no change in the subcellular localization signal was observed. The seedlings of pvsl1 exhibited hypersensitivity to photoinhibition stress. In the pvsl1 mutant, abnormal accumulation of the D1 protein indicated a failure to rapidly degrade damaged D1 protein in the PSII RC. The results of this study demonstrated that PvFtsH2 is critically required for survival and maintaining photosynthetic activity by degrading photodamaged PSII RC D1 protein in common bean.
Collapse
Affiliation(s)
- Kun Xu
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Haping Road 138, Nangang District, 150081, Harbin City, Heilongjiang Province, China
| | - Jinlong Zhu
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Haping Road 138, Nangang District, 150081, Harbin City, Heilongjiang Province, China
| | - Hong Zhai
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Haping Road 138, Nangang District, 150081, Harbin City, Heilongjiang Province, China
| | - Hongyan Wu
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Haping Road 138, Nangang District, 150081, Harbin City, Heilongjiang Province, China
| | - Yi Gao
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Haping Road 138, Nangang District, 150081, Harbin City, Heilongjiang Province, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yuzhuo Li
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Haping Road 138, Nangang District, 150081, Harbin City, Heilongjiang Province, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xiaobin Zhu
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Haping Road 138, Nangang District, 150081, Harbin City, Heilongjiang Province, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Zhengjun Xia
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Haping Road 138, Nangang District, 150081, Harbin City, Heilongjiang Province, China.
| |
Collapse
|
20
|
Xu K, Wu Y, Song J, Hu K, Wu Z, Wen J, Yi B, Ma C, Shen J, Fu T, Tu J. Fine Mapping and Identification of BnaC06.FtsH1, a Lethal Gene That Regulates the PSII Repair Cycle in Brassica napus. Int J Mol Sci 2021; 22:ijms22042087. [PMID: 33669866 PMCID: PMC7923215 DOI: 10.3390/ijms22042087] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 02/14/2021] [Accepted: 02/16/2021] [Indexed: 12/26/2022] Open
Abstract
Photosystem II (PSII) is an important component of the chloroplast. The PSII repair cycle is crucial for the relief of photoinhibition and may be advantageous when improving stress resistance and photosynthetic efficiency. Lethal genes are widely used in the efficiency detection and method improvement of gene editing. In the present study, we identified the naturally occurring lethal mutant 7-521Y with etiolated cotyledons in Brassica napus, controlled by double-recessive genes (named cyd1 and cyd2). By combining whole-genome resequencing and map-based cloning, CYD1 was fine-mapped to a 29 kb genomic region using 15,167 etiolated individuals. Through cosegregation analysis and functional verification of the transgene, BnaC06.FtsH1 was determined to be the target gene; it encodes an filamentation temperature sensitive protein H 1 (FtsH1) hydrolase that degrades damaged PSII D1 in Arabidopsis thaliana. The expression of BnaC06.FtsH1 was high in the cotyledons, leaves, and flowers of B. napus, and localized in the chloroplasts. In addition, the expression of EngA (upstream regulation gene of FtsH) increased and D1 decreased in 7-521Y. Double mutants of FtsH1 and FtsH5 were lethal in A. thaliana. Through phylogenetic analysis, the loss of FtsH5 was identified in Brassica, and the remaining FtsH1 was required for PSII repair cycle. CYD2 may be a homologous gene of FtsH1 on chromosome A07 of B. napus. Our study provides new insights into lethal mutants, the findings may help improve the efficiency of the PSII repair cycle and biomass accumulation in oilseed rape.
Collapse
|
21
|
Adamiec M, Misztal L, Kasprowicz-Maluśki A, Luciński R. EGY3: homologue of S2P protease located in chloroplasts. PLANT BIOLOGY (STUTTGART, GERMANY) 2020; 22:735-743. [PMID: 31886945 DOI: 10.1111/plb.13087] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 12/16/2019] [Indexed: 06/10/2023]
Abstract
The EGY3 protein is a homologue of site-2 proteases, which are intramembrane zinc metalloproteases. EGY3 itself lacks proteolytic activity due to the absence of a zinc-binding motif. Plentiful evidence indicates that such intramembrane 'pseudoproteases' play significant roles in many diverse processes occurring within the cell. However, the physiological functions of EGY3, as well as its subcellular localization, remain unknown. The subcellular localization of EGY3 protein was investigated using Arabidopsis thaliana protoplasts transformed with EGY3-GFP fusion protein, and immunoblot experiments using the total leaf protein extract, as well as highly purified chloroplasts and fractions of stroma, envelope and thylakoid membrane proteins. The physiological role of EGY3 was studied using two A. thaliana mutant lines devoid of EGY3 protein. Chlorophyll a fluorescence measurement was performed and the egy3 mutant sensitivity to photoinhibition was investigated. Additionally, the abundance of thylakoid membrane complexes was established using blue native gel electrophoresis. We present experimental evidence for thylakoid membrane localization of the EGY3 protein. We show that egy3 mutants display increased value of the non-photochemical quenching parameter and significantly slower recovery rate after photoinhibitory treatment. This was associated with a decrease in the level of proteases involved in photosystem II recovery, Deg1 and FtsH2/8.
Collapse
Affiliation(s)
- M Adamiec
- Department of Plant Physiology, Faculty of Biology, Institute of Experimental Biology, Adam Mickiewicz University in Poznań, Poznań, Poland
| | - L Misztal
- Department of Plant Physiology, Faculty of Biology, Institute of Experimental Biology, Adam Mickiewicz University in Poznań, Poznań, Poland
| | - A Kasprowicz-Maluśki
- Department of Molecular and Cellular Biology, Faculty of Biology, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University in Poznań, Poznań, Poland
| | - R Luciński
- Department of Plant Physiology, Faculty of Biology, Institute of Experimental Biology, Adam Mickiewicz University in Poznań, Poznań, Poland
| |
Collapse
|
22
|
Sharpe RM, Gustafson L, Hewitt S, Kilian B, Crabb J, Hendrickson C, Jiwan D, Andrews P, Dhingra A. Concomitant phytonutrient and transcriptome analysis of mature fruit and leaf tissues of tomato (Solanum lycopersicum L. cv. Oregon Spring) grown using organic and conventional fertilizer. PLoS One 2020; 15:e0227429. [PMID: 31931517 PMCID: PMC6957345 DOI: 10.1371/journal.pone.0227429] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 12/18/2019] [Indexed: 12/01/2022] Open
Abstract
Enhanced levels of antioxidants, phenolic compounds, carotenoids and vitamin C have been reported for several crops grown under organic fertilizer, albeit with yield penalties. As organic agricultural practices continue to grow and find favor it is critical to gain an understanding of the molecular underpinnings of the factors that limit the yields in organically farmed crops. Concomitant phytochemical and transcriptomic analysis was performed on mature fruit and leaf tissues derived from Solanum lycopersicum L. ‘Oregon Spring’ grown under organic and conventional fertilizer conditions to evaluate the following hypotheses. 1. Organic soil fertilizer management results in greater allocation of photosynthetically derived resources to the synthesis of secondary metabolites than to plant growth, and 2. Genes involved in changes in the accumulation of phytonutrients under organic fertilizer regime will exhibit differential expression, and that the growth under different fertilizer treatments will elicit a differential response from the tomato genome. Both these hypotheses were supported, suggesting an adjustment of the metabolic and genomic activity of the plant in response to different fertilizers. Organic fertilizer treatment showed an activation of photoinhibitory processes through differential activation of nitrogen transport and assimilation genes resulting in higher accumulation of phytonutrients. This information can be used to identify alleles for breeding crops that allow for efficient utilization of organic inputs.
Collapse
Affiliation(s)
- Richard M. Sharpe
- Department of Horticulture, Washington State University,Pullman, WA, United States of America
- Molecular Plant Sciences Graduate Program, Washington State University, Pullman, WA, United States of America
| | - Luke Gustafson
- Department of Horticulture, Washington State University,Pullman, WA, United States of America
| | - Seanna Hewitt
- Department of Horticulture, Washington State University,Pullman, WA, United States of America
- Molecular Plant Sciences Graduate Program, Washington State University, Pullman, WA, United States of America
| | - Benjamin Kilian
- Department of Horticulture, Washington State University,Pullman, WA, United States of America
- Molecular Plant Sciences Graduate Program, Washington State University, Pullman, WA, United States of America
| | - James Crabb
- Department of Horticulture, Washington State University,Pullman, WA, United States of America
| | - Christopher Hendrickson
- Department of Horticulture, Washington State University,Pullman, WA, United States of America
| | - Derick Jiwan
- Department of Horticulture, Washington State University,Pullman, WA, United States of America
- Molecular Plant Sciences Graduate Program, Washington State University, Pullman, WA, United States of America
| | - Preston Andrews
- Department of Horticulture, Washington State University,Pullman, WA, United States of America
| | - Amit Dhingra
- Department of Horticulture, Washington State University,Pullman, WA, United States of America
- Molecular Plant Sciences Graduate Program, Washington State University, Pullman, WA, United States of America
- * E-mail:
| |
Collapse
|
23
|
The chloroplast metalloproteases VAR2 and EGY1 act synergistically to regulate chloroplast development in Arabidopsis. J Biol Chem 2020. [DOI: 10.1016/s0021-9258(17)49913-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
|
24
|
Shinde S, Zhang X, Singapuri SP, Kalra I, Liu X, Morgan-Kiss RM, Wang X. Glycogen Metabolism Supports Photosynthesis Start through the Oxidative Pentose Phosphate Pathway in Cyanobacteria. PLANT PHYSIOLOGY 2020; 182:507-517. [PMID: 31649110 PMCID: PMC6945877 DOI: 10.1104/pp.19.01184] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 10/17/2019] [Indexed: 06/07/2023]
Abstract
Cyanobacteria experience drastic changes in their carbon metabolism under daily light/dark cycles. During the day, the Calvin-Benson cycle fixes CO2 and diverts excess carbon into glycogen storage. At night, glycogen is degraded to support cellular respiration. The dark/light transition represents a universal environmental stress for cyanobacteria and other photosynthetic lifeforms. Recent studies revealed the essential genetic background necessary for the fitness of cyanobacteria during diurnal growth. However, the metabolic processes underlying the dark/light transition are not well understood. In this study, we observed that glycogen metabolism supports photosynthesis in the cyanobacterium Synechococcus elongatus PCC 7942 when photosynthesis reactions start upon light exposure. Compared with the wild type, the glycogen mutant ∆glgC showed a reduced photosynthetic efficiency and a slower P700+ rereduction rate when photosynthesis starts. Proteomic analyses indicated that glycogen is degraded through the oxidative pentose phosphate (OPP) pathway during the dark/light transition. We confirmed that the OPP pathway is essential for the initiation of photosynthesis and further showed that glycogen degradation through the OPP pathway contributes to the activation of key Calvin-Benson cycle enzymes by modulating NADPH levels. This strategy stimulates photosynthesis in cyanobacteria following dark respiration and stabilizes the Calvin-Benson cycle under fluctuating environmental conditions, thereby offering evolutionary advantages for photosynthetic organisms using the Calvin-Benson cycle for carbon fixation.
Collapse
Affiliation(s)
- Shrameeta Shinde
- Department of Microbiology, Miami University, Oxford, Ohio 45056
| | - Xiaohui Zhang
- Department of Microbiology, Miami University, Oxford, Ohio 45056
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300354, China
| | | | - Isha Kalra
- Department of Microbiology, Miami University, Oxford, Ohio 45056
| | - Xianhua Liu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300354, China
| | | | - Xin Wang
- Department of Microbiology, Miami University, Oxford, Ohio 45056
| |
Collapse
|
25
|
Qi Y, Wang X, Lei P, Li H, Yan L, Zhao J, Meng J, Shao J, An L, Yu F, Liu X. The chloroplast metalloproteases VAR2 and EGY1 act synergistically to regulate chloroplast development in Arabidopsis. J Biol Chem 2019; 295:1036-1046. [PMID: 31836664 DOI: 10.1074/jbc.ra119.011853] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 12/09/2019] [Indexed: 12/29/2022] Open
Abstract
Chloroplast development and photosynthesis require the proper assembly and turnover of photosynthetic protein complexes. Chloroplasts harbor a repertoire of proteases to facilitate proteostasis and development. We have previously used an Arabidopsis leaf variegation mutant, yellow variegated2 (var2), defective in thylakoid FtsH protease complexes, as a tool to dissect the genetic regulation of chloroplast development. Here, we report a new genetic enhancer mutant of var2, enhancer of variegation3-1 (evr3-1). We confirm that EVR3 encodes a chloroplast metalloprotease, reported previously as ethylene-dependent gravitropism-deficient and yellow-green1 (EGY1)/ammonium overly sensitive1 (AMOS1). We observed that mutations in EVR3/EGY1/AMOS1 cause more severe leaf variegation in var2-5 and synthetic lethality in var2-4 Using a modified blue-native PAGE system, we reveal abnormal accumulations of photosystem I, photosystem II, and light-harvesting antenna complexes in EVR3/EGY1/AMOS1 mutants. Moreover, we discover distinct roles of VAR2 and EVR3/EGY1/AMOS1 in the turnover of photosystem II reaction center under high light stress. In summary, our findings indicate that two chloroplast metalloproteases, VAR2/AtFtsH2 and EVR3/EGY1/AMOS1, function coordinately to regulate chloroplast development and reveal new roles of EVR3/EGY1/AMOS1 in regulating chloroplast proteostasis in Arabidopsis.
Collapse
Affiliation(s)
- Yafei Qi
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Xiaomin Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Pei Lei
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Huimin Li
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Liru Yan
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Jun Zhao
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Jingjing Meng
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Jingxia Shao
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Lijun An
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Fei Yu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Xiayan Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| |
Collapse
|
26
|
Li Z, Huang T, Tang M, Cheng B, Peng Y, Zhang X. iTRAQ-based proteomics reveals key role of γ-aminobutyric acid (GABA) in regulating drought tolerance in perennial creeping bentgrass (Agrostis stolonifera). PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2019; 145:216-226. [PMID: 31707249 DOI: 10.1016/j.plaphy.2019.10.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 10/12/2019] [Accepted: 10/15/2019] [Indexed: 05/22/2023]
Abstract
γ-Aminobutyric acid (GABA), a non-proteinaceous amino acid, modulates plant growth and stress tolerance. However, the potential role of GABA in regulating key metabolic pathways and stress-defensive proteins against drought in plants has never been explored. Creeping bentgrass (Agrostis stolonifera) plants were pretreated with or without GABA and then subjected to water stress for 8 days in controlled growth chambers (23/19 °C, day/night). Physiological analysis showed that elevated endogenous GABA level via exogenous GABA application significantly mitigated water stress damage to creeping bentgrass, as manifested by increased leaf relative water content, water use efficiency, osmotic adjustment (OA), photochemical efficiency (Fv/Fm), net photosynthetic rate, and reduced oxidative damage. iTRAQ-based proteomics found that enhanced chaperones accumulation, carbohydrates, amino acids, and energy metabolism played important roles in protein protection, OA, energy maintenance, and metabolic balance, which is important adaptive response to drought stress in creeping bentgrass. The GABA further promoted energy production and conversion, antioxidant defense, and DHN3 accumulation that were essential for energy requirement, ROS-scavenging, and the prevention of cell dehydration in leaf during drought stress. In addition, GABA-treated plants maintained significantly higher abundance of dicarboxylate transporter 2.1, ATP-dependent zinc metalloprotease, receptor-like protein kinase HERK1, o-acyltransferase WSD1, omega-6 fatty acid desaturase, and two-component response regulator ORR21 than untreated plants under drought stress. The result provides new evidences that GABA-induced drought tolerance is possibly involved in the improvement of nitrogen recycling, protection of photosystem II, mitigation of drought-depressed cell elongation, wax biosynthesis, fatty acid desaturase, and delaying leaf senescence in creeping bentgrass.
Collapse
Affiliation(s)
- Zhou Li
- Department of Grassland Science, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 611130, China
| | - Ting Huang
- Department of Grassland Science, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 611130, China
| | - Mingyan Tang
- Department of Grassland Science, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 611130, China
| | - Binzhen Cheng
- Department of Grassland Science, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 611130, China
| | - Yan Peng
- Department of Grassland Science, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 611130, China
| | - Xinquan Zhang
- Department of Grassland Science, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 611130, China.
| |
Collapse
|
27
|
Tränkner M, Jamali Jaghdani S. Minimum magnesium concentrations for photosynthetic efficiency in wheat and sunflower seedlings. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2019; 144:234-243. [PMID: 31590092 DOI: 10.1016/j.plaphy.2019.09.040] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 09/23/2019] [Accepted: 09/23/2019] [Indexed: 05/27/2023]
Abstract
Photosynthetic processes in the chloroplast depend on the abundance of magnesium (Mg) in relatively high amounts; hence chloroplasts might react more sensitive to Mg-deficiency than other physiological processes within other organelles. Most authors suggest a critical Mg concentration to be 1.5 mg g-1 DM for biomass and yield formation. However, it is not yet elucidated whether this value also applies to photosynthetic processes. The present study focused on the response of photosynthetic processes to different Mg tissue concentrations. Wheat (Triticum aestivum) and sunflower (Helianthus annuus) plants were grown hydroponically for 10 days with 8 different levels of Mg supply (1.0, 0.5, 0.25, 0.1, 0.075, 0.05, 0.025, 0.01 mM Mg). Specific leaf mass, SPAD values, assimilation rate, Fv/Fm, electron transport rate and photochemical and non-photochemical quenching parameters were determined on youngest mature leaves. Tissue Mg concentrations decreased with lowering Mg supply to lowest concentrations of 0.7 mg g-1 DM in wheat leaves, but photosynthetic capacity was not affected. In sunflower leaves, lowest Mg concentrations of 0.56 mg g-1 DM were achieved and a diminished photosynthetic capacity was observed. The study shows that a Mg tissue concentration of 1.5 mg g-1 DM did not induce a negative effect on the photosynthetic capacity of wheat and sunflower leaves under our experimental conditions and hence, the critical Mg concentration for photosynthetic processes might be lower than for biomass and yield formation.
Collapse
Affiliation(s)
- Merle Tränkner
- Institute of Applied Plant Nutrition (IAPN), Georg-August University Goettingen, 37075, Goettingen, Germany.
| | - Setareh Jamali Jaghdani
- Institute of Applied Plant Nutrition (IAPN), Georg-August University Goettingen, 37075, Goettingen, Germany
| |
Collapse
|
28
|
Photosystem II oxygen-evolving complex photoassembly displays an inverse H/D solvent isotope effect under chloride-limiting conditions. Proc Natl Acad Sci U S A 2019; 116:18917-18922. [PMID: 31484762 PMCID: PMC6754581 DOI: 10.1073/pnas.1910231116] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Metal clusters play important roles in a wide variety of proteins. In cyanobacteria, algae, and plants, photosystem II uses light energy to oxidize water and release O2 at an active site that contains 1 calcium and 4 manganese atoms. This cluster must be built within the protein environment through a process known as photoassembly. Through experiments and simulations, we found that the efficiency of photoassembly was highly dependent on protons and chloride. Surprisingly, when the solvent was switched from H2O to deuterated water, D2O, the yield of photoassembly was higher. These results provide insights into the stepwise mechanism of photoassembly that can inform synthesis and repair strategies being developed for artificial photosynthesis technologies. Photosystem II (PSII) performs the solar-driven oxidation of water used to fuel oxygenic photosynthesis. The active site of water oxidation is the oxygen-evolving complex (OEC), a Mn4CaO5 cluster. PSII requires degradation of key subunits and reassembly of the OEC as frequently as every 20 to 40 min. The metals for the OEC are assembled within the PSII protein environment via a series of binding events and photochemically induced oxidation events, but the full mechanism is unknown. A role of proton release in this mechanism is suggested here by the observation that the yield of in vitro OEC photoassembly is higher in deuterated water, D2O, compared with H2O when chloride is limiting. In kinetic studies, OEC photoassembly shows a significant lag phase in H2O at limiting chloride concentrations with an apparent H/D solvent isotope effect of 0.14 ± 0.05. The growth phase of OEC photoassembly shows an H/D solvent isotope effect of 1.5 ± 0.2. We analyzed the protonation states of the OEC protein environment using classical Multiconformer Continuum Electrostatics. Combining experiments and simulations leads to a model in which protons are lost from amino acid that will serve as OEC ligands as metals are bound. Chloride and D2O increase the proton affinities of key amino acid residues. These residues tune the binding affinity of Mn2+/3+ and facilitate the deprotonation of water to form a proposed μ-hydroxo bridged Mn2+Mn3+ intermediate.
Collapse
|
29
|
Tamary E, Nevo R, Naveh L, Levin‐Zaidman S, Kiss V, Savidor A, Levin Y, Eyal Y, Reich Z, Adam Z. Chlorophyll catabolism precedes changes in chloroplast structure and proteome during leaf senescence. PLANT DIRECT 2019; 3:e00127. [PMID: 31245770 PMCID: PMC6508775 DOI: 10.1002/pld3.127] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 02/25/2019] [Accepted: 02/26/2019] [Indexed: 05/18/2023]
Abstract
The earliest visual changes of leaf senescence occur in the chloroplast as chlorophyll is degraded and photosynthesis declines. Yet, a comprehensive understanding of the sequence of catabolic events occurring in chloroplasts during natural leaf senescence is still missing. Here, we combined confocal and electron microscopy together with proteomics and biochemistry to follow structural and molecular changes during Arabidopsis leaf senescence. We observed that initiation of chlorophyll catabolism precedes other breakdown processes. Chloroplast size, stacking of thylakoids, and efficiency of PSII remain stable until late stages of senescence, whereas the number and size of plastoglobules increase. Unlike catabolic enzymes, whose level increase, the level of most proteins decreases during senescence, and chloroplast proteins are overrepresented among these. However, the rate of their disappearance is variable, mostly uncoordinated and independent of their inherent stability during earlier developmental stages. Unexpectedly, degradation of chlorophyll-binding proteins lags behind chlorophyll catabolism. Autophagy and vacuole proteins are retained at relatively high levels, highlighting the role of extra-plastidic degradation processes especially in late stages of senescence. The observation that chlorophyll catabolism precedes all other catabolic events may suggest that this process enables or signals further catabolic processes in chloroplasts.
Collapse
Affiliation(s)
- Eyal Tamary
- The Robert H. Smith Institute of Plant Sciences and Genetics in AgricultureThe Hebrew UniversityRehovotIsrael
| | - Reinat Nevo
- Department of Biomolecular SciencesWeizmann Institute of ScienceRehovotIsrael
| | - Leah Naveh
- The Robert H. Smith Institute of Plant Sciences and Genetics in AgricultureThe Hebrew UniversityRehovotIsrael
| | - Smadar Levin‐Zaidman
- Department of Chemical Research SupportWeizmann Institute of ScienceRehovotIsrael
| | - Vladimir Kiss
- Department of Biomolecular SciencesWeizmann Institute of ScienceRehovotIsrael
| | - Alon Savidor
- de Botton Institute for Protein ProfilingThe Nancy and Stephen Grand Israel National Center for Personalized MedicineWeizmann Institute of ScienceRehovotIsrael
| | - Yishai Levin
- de Botton Institute for Protein ProfilingThe Nancy and Stephen Grand Israel National Center for Personalized MedicineWeizmann Institute of ScienceRehovotIsrael
| | - Yoram Eyal
- Institute of Plant SciencesThe Volcani Center ARORishon LeZionIsrael
| | - Ziv Reich
- Department of Biomolecular SciencesWeizmann Institute of ScienceRehovotIsrael
| | - Zach Adam
- The Robert H. Smith Institute of Plant Sciences and Genetics in AgricultureThe Hebrew UniversityRehovotIsrael
| |
Collapse
|
30
|
Kato Y, Sakamoto W. Phosphorylation of the Chloroplastic Metalloprotease FtsH in Arabidopsis Characterized by Phos-Tag SDS-PAGE. FRONTIERS IN PLANT SCIENCE 2019; 10:1080. [PMID: 31552075 PMCID: PMC6747001 DOI: 10.3389/fpls.2019.01080] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 08/08/2019] [Indexed: 05/07/2023]
Abstract
FtsH is an essential ATP-dependent metalloprotease for protein quality control in the thylakoid membrane of Arabidopsis thaliana chloroplasts. It is required for chloroplast development during leaf growth, and particularly for the specific degradation of photo-damaged D1 protein in the photosystem II (PSII) complex to maintain photosynthesis activity. In the thylakoid membrane, the reversible phosphorylation of proteins is known to control the activity and remodeling of photosynthetic complexes, and previous studies implicate that FtsH is also phosphorylated. We therefore assessed the phosphorylation status of FtsH and its possible role in the regulatory mechanism in this study. The phosphorylation level of FtsHs that compose the FtsH heterohexameric complex was investigated by phosphate-affinity gel electrophoresis using a Phos-Tag molecule. Phos-tag SDS-PAGE of thylakoid proteins and subsequent immunoblot analysis showed that both type A (FtsH1/5) and type B (FtsH2/8) subunits were separable into phosphorylated and non-phosphorylated forms. Neither different light conditions nor the lack of two major thylakoid kinases, STN7 and STN8, resulted in any clear difference in FtsH phosphorylation, suggesting that this process is independent of the light-dependent regulation of photosynthesis-related proteins. Site-directed mutagenesis of putatively phosphorylated Ser or Thr residues into Ala demonstrated that Ser-212 may play a role in FtsH stability in the thylakoid membranes. Different phosphorylation status of FtsH oligomers analyzed by two-dimensional clear-native/Phos-tag SDS-PAGE implied that phosphorylation partially affects FtsH complex formation or its stability.
Collapse
|
31
|
Wang L, Apel K. Dose-dependent effects of 1O2 in chloroplasts are determined by its timing and localization of production. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:29-40. [PMID: 30272237 PMCID: PMC6939833 DOI: 10.1093/jxb/ery343] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2018] [Accepted: 09/25/2018] [Indexed: 05/23/2023]
Abstract
In plants, highly reactive singlet oxygen (1O2) is known to inhibit photosynthesis and to damage the cell as a cytotoxin. However, more recent studies have also proposed 1O2 as a signal. In plants under stress, not only 1O2 but also other reactive oxygen species (ROS) are generated simultaneously, thus making it difficult to link a particular response to the release of 1O2 and establish a signaling role for this ROS. This obstacle has been overcome by the identification of conditional mutants of Arabidopsis thaliana that selectively generate 1O2 and trigger various 1O2-mediated responses. In chloroplasts of these mutants, chlorophyll or its biosynthetic intermediates may act as a photosensitizer and generate 1O2. These 1O2-mediated responses are not only dependent on the dosage of 1O2 but also are determined by the timing and suborganellar localization of its production. This spatial- and temporal-dependent variability of 1O2-mediated responses emphasizes the importance of 1O2 as a highly versatile and short-lived signal that acts throughout the life cycle of a plant.
Collapse
Affiliation(s)
- Liangsheng Wang
- Boyce Thompson Institute, Ithaca, NY, USA
- Plant Molecular Biology (Botany), Department Biology I, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Klaus Apel
- Boyce Thompson Institute, Ithaca, NY, USA
- Institute of Molecular Plant Biology, Swiss Federal Institute of Technology (ETH), Zürich, Switzerland
| |
Collapse
|
32
|
Liu S, Zheng L, Jia J, Guo J, Zheng M, Zhao J, Shao J, Liu X, An L, Yu F, Qi Y. Chloroplast Translation Elongation Factor EF-Tu/SVR11 Is Involved in var2-Mediated Leaf Variegation and Leaf Development in Arabidopsis. FRONTIERS IN PLANT SCIENCE 2019; 10:295. [PMID: 30915096 PMCID: PMC6423176 DOI: 10.3389/fpls.2019.00295] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 02/22/2019] [Indexed: 05/02/2023]
Abstract
Chloroplasts are semiautonomous organelles, retaining their own genomes and gene expression apparatuses but controlled by nucleus genome encoded protein factors during evolution. To analyze the genetic regulatory network of FtsH-mediated chloroplast development in Arabidopsis, a set of suppressor mutants of yellow variegated (var2) have been identified. In this research, we reported the identification of another new var2 suppressor locus, SUPPRESSOR OF VARIEGATION11 (SVR11), which encodes a putative chloroplast-localized prokaryotic type translation elongation factor EF-Tu. SVR11 is likely essential to chloroplast development and plant survival. GUS activity reveals that SVR11 is abundant in the juvenile leaf tissue, lateral roots, and root tips. Interestingly, we found that SVR11 and SVR9 together regulate leaf development, including leaf margin development and cotyledon venation patterns. These findings reinforce the notion that chloroplast translation state triggers retrograde signals regulate not only chloroplast development but also leaf development.
Collapse
|
33
|
Adam Z, Aviv-Sharon E, Keren-Paz A, Naveh L, Rozenberg M, Savidor A, Chen J. The Chloroplast Envelope Protease FTSH11 - Interaction With CPN60 and Identification of Potential Substrates. FRONTIERS IN PLANT SCIENCE 2019; 10:428. [PMID: 31024594 PMCID: PMC6459962 DOI: 10.3389/fpls.2019.00428] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 03/21/2019] [Indexed: 05/03/2023]
Abstract
FTSH proteases are membrane-bound, ATP-dependent metalloproteases found in bacteria, mitochondria and chloroplasts. The product of one of the 12 genes encoding FTSH proteases in Arabidopsis, FTSH11, has been previously shown to be essential for acquired thermotolerance. However, the substrates of this protease, as well as the mechanism linking it to thermotolerance are largely unknown. To get insight into these, the FTSH11 knockout mutant was complemented with proteolytically active or inactive variants of this protease, tagged with HA-tag, under the control of the native promoter. Using these plants in thermotolerance assay demonstrated that the proteolytic activity, and not only the ATPase one, is essential for conferring thermotolerance. Immunoblot analyses of leaf extracts, isolated organelles and sub-fractionated chloroplast membranes localized FTSH11 mostly to chloroplast envelopes. Affinity purification followed by mass spectrometry analysis revealed interaction between FTSH11 and different components of the CPN60 chaperonin. In affinity enrichment assays, CPN60s as well as a number of envelope, stroma and thylakoid proteins were found associated with proteolytically inactive FTSH11. Comparative proteomic analysis of WT and knockout plants, grown at 20°C or exposed to 30°C for 6 h, revealed a plethora of upregulated chloroplast proteins in the knockout, some of them might be candidate substrates. Among these stood out TIC40, which was stabilized in the knockout line after recovery from heat stress, and three proteins that were found trapped in the affinity enrichment assay: the nucleotide antiporter PAPST2, the fatty acid binding protein FAP1 and the chaperone HSP70. The consistent behavior of these four proteins in different assays suggest that they are potential FTSH11 substrates.
Collapse
Affiliation(s)
- Zach Adam
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot, Israel
- *Correspondence: Zach Adam,
| | - Elinor Aviv-Sharon
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Alona Keren-Paz
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Leah Naveh
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Mor Rozenberg
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Alon Savidor
- de Botton Institute for Protein Profiling, The Nancy and Stephen Grand Israel National Center for Personalized Medicine, Weizmann Institute of Science, Rehovot, Israel
| | - Junping Chen
- Plant Stress and Germplasm Development Unit, USDA-ARS, Lubbock, TX, United States
| |
Collapse
|
34
|
Kato Y, Hyodo K, Sakamoto W. The Photosystem II Repair Cycle Requires FtsH Turnover through the EngA GTPase. PLANT PHYSIOLOGY 2018; 178:596-611. [PMID: 30131421 PMCID: PMC6181060 DOI: 10.1104/pp.18.00652] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 08/08/2018] [Indexed: 05/03/2023]
Abstract
Specific degradation of photodamaged D1, the photosystem II (PSII) reaction center protein, is a crucial step in the PSII repair cycle to maintain photosynthesis activity. Processive proteolysis by the FtsH protease is fundamental to cooperative D1 degradation. Here, we attempted to purify the FtsH complex to elucidate its regulation mechanisms and substrate recognition in Arabidopsis (Arabidopsis thaliana). Unlike previously reported prokaryotic and mitochondrial FtsHs, the Arabidopsis chloroplastic FtsH does not appear to form a megacomplex with prohibition-like proteins but instead accumulates as smaller complexes. The copurified fraction was enriched with a partial PSII intermediate presumably undergoing repair, although its precise properties were not fully clarified. In addition, we copurified a bacteria-type GTPase localized in chloroplasts, EngA, and confirmed its interaction with FtsH by subsequent pull-down and bimolecular fluorescence complementation assays. While the engA mutation is embryo lethal, the transgenic lines overexpressing EngA (EngA-OX) showed leaf variegation reminiscent of the variegated mutant lacking FtsH2. EngA-OX was revealed to accumulate more cleaved D1 fragments and reactive oxygen species than the wild type, indicative of compromised PSII repair. Based on these results and the fact that FtsH becomes more stable in EngA-OX, we propose that EngA negatively regulates FtsH stability. We demonstrate that proper FtsH turnover is crucial for PSII repair in the chloroplasts of Arabidopsis. Consistent with the increased turnover of FtsH under high-light conditions in Chlamydomonas reinhardtii, our findings underline the rapid turnover of not only D1 but also FtsH proteases in the PSII repair cycle.
Collapse
Affiliation(s)
- Yusuke Kato
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Okayama 710-0046, Japan
| | - Kiwamu Hyodo
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Okayama 710-0046, Japan
| | - Wataru Sakamoto
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Okayama 710-0046, Japan
| |
Collapse
|
35
|
Townsend AJ, Ware MA, Ruban AV. Dynamic interplay between photodamage and photoprotection in photosystem II. PLANT, CELL & ENVIRONMENT 2018; 41:1098-1112. [PMID: 29210070 DOI: 10.1111/pce.13107] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 11/20/2017] [Accepted: 11/21/2017] [Indexed: 06/07/2023]
Abstract
Photoinhibition is the light-induced reduction in photosynthetic efficiency and is usually associated with damage to the D1 photosystem II (PSII) reaction centre protein. This damage must either be repaired, through the PSII repair cycle, or prevented in the first place by nonphotochemical quenching (NPQ). Both NPQ and D1 repair contribute to light tolerance because they ensure the long-term maintenance of the highest quantum yield of PSII. However, the relative contribution of each of these processes is yet to be elucidated. The application of a pulse amplitude modulation fluorescence methodology, called protective NPQ, enabled us to evaluate of the protective effectiveness of the processes. Within this study, the contribution of NPQ and D1 repair to the photoprotective capacity of Arabidopsis thaliana was elucidated by using inhibitors and mutants known to affect each process. We conclude that NPQ contributes a greater amount to the maintenance of a high PSII yield than D1 repair under short periods of illumination. This research further supports the role of protective components of NPQ during light fluctuations and the value of protective NPQ and qPd as unambiguous fluorescence parameters, as opposed to qI and Fv /Fm , for quantifying photoinactivation of reaction centre II and light tolerance of photosynthetic organisms.
Collapse
Affiliation(s)
- Alexandra J Townsend
- School of Biological and Chemical Sciences, Queen Mary University of London, London, E14NS, UK
| | - Maxwell A Ware
- School of Biological and Chemical Sciences, Queen Mary University of London, London, E14NS, UK
| | - Alexander V Ruban
- School of Biological and Chemical Sciences, Queen Mary University of London, London, E14NS, UK
| |
Collapse
|
36
|
Davey PA, Pernice M, Ashworth J, Kuzhiumparambil U, Szabó M, Dolferus R, Ralph PJ. A new mechanistic understanding of light-limitation in the seagrass Zostera muelleri. MARINE ENVIRONMENTAL RESEARCH 2018; 134:55-67. [PMID: 29307464 DOI: 10.1016/j.marenvres.2017.12.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Revised: 11/12/2017] [Accepted: 12/17/2017] [Indexed: 05/28/2023]
Abstract
In this study we investigated the effect of light-limitation (∼20 μmol photons m-2 s-1) on the southern hemisphere seagrass, Zostera muelleri. RNA sequencing, chlorophyll fluorometry and HPLC techniques were used to investigate how the leaf-specific transcriptome drives changes in photosynthesis and photo-pigments in Z. muelleri over 6 days. 1593 (7.51%) genes were differentially expressed on day 2 and 1481 (6.98%) genes were differentially expressed on day 6 of the experiment. Differential gene expression correlated with significant decreases in rETRMax, Ik, an increase in Yi (initial photosynthetic quantum yield of photosystem II), and significant changes in pigment composition. Regulation of carbohydrate metabolism was observed along with evidence that abscisic acid may serve a role in the low-light response of this seagrass. This study provides a novel understanding of how Z. muelleri responds to light-limitation in the marine water column and provides potential molecular markers for future conservation monitoring efforts.
Collapse
Affiliation(s)
- Peter A Davey
- Climate Change Cluster, University of Technology Sydney, NSW, Australia; Centre for Tropical Water and Aquatic Ecosystem Research (TropWater), James Cook University, Cairns, QLD, Australia.
| | - Mathieu Pernice
- Climate Change Cluster, University of Technology Sydney, NSW, Australia
| | - Justin Ashworth
- Climate Change Cluster, University of Technology Sydney, NSW, Australia
| | | | - Milán Szabó
- Climate Change Cluster, University of Technology Sydney, NSW, Australia
| | - Rudy Dolferus
- CSIRO Agriculture and Food, Black Mountain, Canberra, ACT, Australia
| | - Peter J Ralph
- Climate Change Cluster, University of Technology Sydney, NSW, Australia
| |
Collapse
|
37
|
Otegui MS. Vacuolar degradation of chloroplast components: autophagy and beyond. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:741-750. [PMID: 28992297 DOI: 10.1093/jxb/erx234] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 07/10/2017] [Indexed: 05/21/2023]
Abstract
Chloroplast degradation during natural or stress-induced senescence requires the participation of both plastidic and extraplastidic degradative pathways. As part of the extraplastidic pathways, chloroplasts export stroma, envelope, and thylakoid proteins in membrane-bound organelles that are ultimately degraded in vacuoles. Some of these pathways, such as the formation of senescence-associated vacuoles (SAVs) and CV-containing vesicles (CCVs), do not depend on autophagy, whereas delivery of Rubisco-containing bodies (RCBs), ATI1-PS (ATG8-interacting Protein 1) bodies, and small starch-like granule (SSLG) bodies is autophagy dependent. In addition, autophagy of entire chloroplasts delivers damaged chloroplasts into the vacuolar lumen for degradation. This review summarizes the autophagy-dependent and independent trafficking mechanisms by which plant cells degrade chloroplast components in vacuoles.
Collapse
Affiliation(s)
- Marisa S Otegui
- Laboratory of Cell and Molecular Biology and Departments of Botany and Genetics, University of Wisconsin-Madison, WI, USA
| |
Collapse
|
38
|
Murata N, Nishiyama Y. ATP is a driving force in the repair of photosystem II during photoinhibition. PLANT, CELL & ENVIRONMENT 2018; 41:285-299. [PMID: 29210214 DOI: 10.1111/pce.13108] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 11/21/2017] [Accepted: 11/22/2017] [Indexed: 05/15/2023]
Abstract
Repair of photosystem II (PSII) during photoinhibition involves replacement of photodamaged D1 protein by newly synthesized D1 protein. In this review, we summarize evidence for the indispensability of ATP in the degradation and synthesis of D1 during the repair of PSII. Synthesis of one molecule of the D1 protein consumes more than 1,300 molecules of ATP equivalents. The degradation of photodamaged D1 by FtsH protease also consumes approximately 240 molecules of ATP. In addition, ATP is required for several other aspects of the repair of PSII, such as transcription of psbA genes. These requirements for ATP during the repair of PSII have been demonstrated by experiments showing that the synthesis of D1 and the repair of PSII are interrupted by inhibitors of ATP synthase and uncouplers of ATP synthesis, as well as by mutation of components of ATP synthase. We discuss the contribution of cyclic electron transport around photosystem I to the repair of PSII. Furthermore, we introduce new terms relevant to the regulation of the PSII repair, namely, "ATP-dependent regulation" and "redox-dependent regulation," and we discuss the possible contribution of the ATP-dependent regulation of PSII repair under environmental stress.
Collapse
Affiliation(s)
- Norio Murata
- National Institute for Basic Biology, Okazaki, 444-8585, Japan
| | - Yoshitaka Nishiyama
- Department of Biochemistry and Molecular Biology and Institute for Environmental Science and Technology, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama, 338-8570, Japan
| |
Collapse
|
39
|
Chen J, Burke JJ, Xin Z. Chlorophyll fluorescence analysis revealed essential roles of FtsH11 protease in regulation of the adaptive responses of photosynthetic systems to high temperature. BMC PLANT BIOLOGY 2018; 18:11. [PMID: 29320985 PMCID: PMC5763919 DOI: 10.1186/s12870-018-1228-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2017] [Accepted: 01/04/2018] [Indexed: 05/20/2023]
Abstract
BACKGROUND Photosynthetic systems are known to be sensitive to high temperature stress. To maintain a relatively "normal" level of photosynthetic activities, plants employ a variety of adaptive mechanisms in response to environmental temperature fluctuations. Previously, we reported that the chloroplast-targeted AtFtsH11 protease played an essential role for Arabidopsis plants to survive at high temperatures and to maintain normal photosynthetic efficiency at moderately elevated temperature. To investigate the factors contributing to the photosynthetic changes in FtsH11 mutant, we performed detailed chlorophyll fluorescence analyses of dark-adapted mutant plants and compared them to Col-0 WT plants under normal, two moderate high temperatures, and a high light conditions. RESULTS We found that mutation of FtsH11 gene caused significant decreases in photosynthetic efficiency of photosystems when environmental temperature raised above optimal. Under moderately high temperatures, the FtsH11 mutant showed significant 1) decreases in electron transfer rates of photosystem II (PSII) and photosystem I (PSI), 2) decreases in photosynthetic capabilities of PSII and PSI, 3) increases in non-photochemical quenching, and a host of other chlorophyll fluorescence parameter changes. We also found that the degrees of these negative changes for utilizing the absorbed light energy for photosynthesis in FtsH11 mutant were correlated with the level and duration of the heat treatments. For plants grown under normal temperature and subjected to the high light treatment, no significant difference in chlorophyll fluorescence parameters was found between the FtsH11 mutant and Col-0 WT plants. CONCLUSIONS The results of this study show that AtFtsH11 is essential for normal photosynthetic function under moderately elevated temperatures. The results also suggest that the network mediated by AtFtsH11 protease plays critical roles for maintaining the thermostability and possibly structural integrity of both photosystems under elevated temperatures. Elucidating the underlying mechanisms of FtsH11 protease in photosystems may lead to improvement of photosynthetic efficiency under heat stress conditions, hence, plant productivity.
Collapse
Affiliation(s)
- Junping Chen
- Plant Stress and Germplasm Development Unit, USDA-ARS, 3810 4th Street, Lubbock, TX 79415 USA
| | - John J. Burke
- Plant Stress and Germplasm Development Unit, USDA-ARS, 3810 4th Street, Lubbock, TX 79415 USA
| | - Zhanguo Xin
- Plant Stress and Germplasm Development Unit, USDA-ARS, 3810 4th Street, Lubbock, TX 79415 USA
| |
Collapse
|
40
|
Wang R, Zhao J, Jia M, Xu N, Liang S, Shao J, Qi Y, Liu X, An L, Yu F. Balance between Cytosolic and Chloroplast Translation Affects Leaf Variegation. PLANT PHYSIOLOGY 2018; 176:804-818. [PMID: 29142022 PMCID: PMC5761769 DOI: 10.1104/pp.17.00673] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 11/13/2017] [Indexed: 05/08/2023]
Abstract
The development of functional chloroplasts relies on the fine coordination of expressions of both nuclear and chloroplast genomes. We have been using the Arabidopsis (Arabidopsis thaliana) yellow variegated (var2) leaf variegation mutant as a tool to dissect the regulation of chloroplast development. In this work, we screened for var2 genetic enhancer modifiers termed enhancer of variegation (evr) mutants and report the characterization of the first EVR locus, EVR1 We showed that EVR1 encodes the cytosolic 80S ribosome 40S small subunit protein RPS21B and the loss of EVR1 causes the enhancement of var2 leaf variegation. We further demonstrated that combined S21 activities from EVR1 and its close homolog, EVR1L1, are essential for Arabidopsis, and they act redundantly in regulating leaf development and var2 leaf variegation. Moreover, using additional cytosolic ribosomal protein mutants, we showed that although mutations in cytosolic ribosomal proteins all enhance var2 leaf variegation to varying degrees, the 40S subunit appears to have a more profound role over the 60S subunit in regulating VAR2-mediated chloroplast development. Comprehensive genetic analyses with var2 suppressors that are defective in chloroplast translation established that the enhancement of var2 leaf variegation by cytosolic ribosomal protein mutants is dependent on chloroplast translation. Based on our data, we propose a model that incorporates the suppression and enhancement of var2 leaf variegation, and hypothesize that VAR2/AtFtsH2 may be intimately involved in the balancing of cytosolic and chloroplast translation programs during chloroplast biogenesis.
Collapse
Affiliation(s)
- Ruijuan Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Jun Zhao
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Min Jia
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Ni Xu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Shuang Liang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Jingxia Shao
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Yafei Qi
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Xiayan Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Lijun An
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Fei Yu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| |
Collapse
|
41
|
Lopes KL, Rodrigues RAO, Silva MC, Braga WGS, Silva-Filho MC. The Zinc-Finger Thylakoid-Membrane Protein FIP Is Involved With Abiotic Stress Response in Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2018; 9:504. [PMID: 29720990 PMCID: PMC5915565 DOI: 10.3389/fpls.2018.00504] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 04/03/2018] [Indexed: 05/15/2023]
Abstract
Many plant genes have their expression modulated by stress conditions. Here, we used Arabidopsis FtsH5 protease, which expression is regulated by light stress, as bait in a yeast two-hybrid screen to search for new proteins involved in the stress response. As a result, we found FIP (FtsH5 Interacting Protein), which possesses an amino proximal cleavable transit peptide, a hydrophobic membrane-anchoring region, and a carboxyl proximal C4-type zinc-finger domain. In vivo experiments using FIP fused to green fluorescent protein (GFP) showed a plastid localization. This finding was corroborated by chloroplast import assays that showed FIP inserted in the thylakoid membrane. FIP expression was down-regulated in plants exposed to high light intensity, oxidative, salt, and osmotic stresses, whereas mutant plants expressing low levels of FIP were more tolerant to these abiotic stresses. Our data shows a new thylakoid-membrane protein involved with abiotic stress response in Arabidopsis thaliana.
Collapse
|
42
|
Kato Y, Sakamoto W. FtsH Protease in the Thylakoid Membrane: Physiological Functions and the Regulation of Protease Activity. FRONTIERS IN PLANT SCIENCE 2018; 9:855. [PMID: 29973948 PMCID: PMC6019477 DOI: 10.3389/fpls.2018.00855] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 06/01/2018] [Indexed: 05/18/2023]
Abstract
Protein homeostasis in the thylakoid membranes is dependent on protein quality control mechanisms, which are necessary to remove photodamaged and misfolded proteins. An ATP-dependent zinc metalloprotease, FtsH, is the major thylakoid membrane protease. FtsH proteases in the thylakoid membranes of Arabidopsis thaliana form a hetero-hexameric complex consisting of four FtsH subunits, which are divided into two types: type A (FtsH1 and FtsH5) and type B (FtsH2 and FtsH8). An increasing number of studies have identified the critical roles of FtsH in the biogenesis of thylakoid membranes and quality control in the photosystem II repair cycle. Furthermore, the involvement of FtsH proteolysis in a singlet oxygen- and EXECUTER1-dependent retrograde signaling mechanism has been suggested recently. FtsH is also involved in the degradation and assembly of several protein complexes in the photosynthetic electron-transport pathways. In this minireview, we provide an update on the functions of FtsH in thylakoid biogenesis and describe our current understanding of the D1 degradation processes in the photosystem II repair cycle. We also discuss the regulation mechanisms of FtsH protease activity, which suggest the flexible oligomerization capability of FtsH in the chloroplasts of seed plants.
Collapse
|
43
|
Kim JI, Moore CE, Archibald JM, Bhattacharya D, Yi G, Yoon HS, Shin W. Evolutionary Dynamics of Cryptophyte Plastid Genomes. Genome Biol Evol 2017; 9:1859-1872. [PMID: 28854597 PMCID: PMC5534331 DOI: 10.1093/gbe/evx123] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/03/2017] [Indexed: 12/14/2022] Open
Abstract
Cryptophytes are an ecologically important group of largely photosynthetic unicellular eukaryotes. This lineage is of great interest to evolutionary biologists because their plastids are of red algal secondary endosymbiotic origin and the host cell retains four different genomes (host nuclear, mitochondrial, plastid, and red algal nucleomorph). Here, we report a comparative analysis of plastid genomes from six representative cryptophyte genera. Four newly sequenced cryptophyte plastid genomes of Chroomonas mesostigmatica, Ch. placoidea, Cryptomonas curvata, and Storeatula sp. CCMP1868 share a number of features including synteny and gene content with the previously sequenced genomes of Cryptomonas paramecium, Rhodomonas salina, Teleaulax amphioxeia, and Guillardia theta. Our analysis of these plastid genomes reveals examples of gene loss and intron insertion. In particular, the chlB/chlL/chlN genes, which encode light-independent (dark active) protochlorophyllide oxidoreductase (LIPOR) proteins have undergone recent gene loss and pseudogenization in cryptophytes. Comparison of phylogenetic trees based on plastid and nuclear genome data sets show the introduction, via secondary endosymbiosis, of a red algal derived plastid in a lineage of chlorophyll-c containing algae. This event was followed by additional rounds of eukaryotic endosymbioses that spread the red lineage plastid to diverse groups such as haptophytes and stramenopiles.
Collapse
Affiliation(s)
- Jong Im Kim
- Department of Biology, Chungnam National University, Daejeon, Korea
| | - Christa E Moore
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - John M Archibald
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
| | | | - Gangman Yi
- Department of Multimedia Engineering, Dongkuk University, Seoul, Korea
| | - Hwan Su Yoon
- Department of Biological Sciences, Sungkyunkwan University, Suwon, Korea
| | - Woongghi Shin
- Department of Biology, Chungnam National University, Daejeon, Korea
| |
Collapse
|
44
|
Ortiz D, Hu J, Salas Fernandez MG. Genetic architecture of photosynthesis in Sorghum bicolor under non-stress and cold stress conditions. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:4545-4557. [PMID: 28981780 PMCID: PMC5853419 DOI: 10.1093/jxb/erx276] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 07/15/2017] [Indexed: 05/18/2023]
Abstract
Sorghum (Sorghum bicolor L. Moench) is a C4 species sensitive to the cold spring conditions that occur at northern latitudes, especially when coupled with excessive light, and that greatly affect the photosynthetic rate. The objective of this study was to discover genes/genomic regions that control the capacity to cope with excessive energy under low temperature conditions during the vegetative growth period. A genome-wide association study (GWAS) was conducted for seven photosynthetic gas exchange and chlorophyll fluorescence traits under three consecutive temperature treatments: control (28 °C/24 °C), cold (15 °C/15 °C), and recovery (28 °C/24 °C). Cold stress significantly reduced the rate of photosynthetic CO2 uptake of sorghum plants, and a total of 143 unique genomic regions were discovered associated with at least one trait in a particular treatment or with derived variables. Ten regions on chromosomes 3, 4, 6, 7, and 8 that harbor multiple significant markers in linkage disequilibrium (LD) were consistently identified in gas exchange and chlorophyll fluorescence traits. Several candidate genes within those intervals have predicted functions related to carotenoids, phytohormones, thioredoxin, components of PSI, and antioxidants. These regions represent the most promising results for future validation and with potential application for the improvement of crop productivity under cold stress.
Collapse
Affiliation(s)
- Diego Ortiz
- Department of Agronomy, Iowa State University, Ames, IA, USA
| | - Jieyun Hu
- Department of Agronomy, Iowa State University, Ames, IA, USA
| | | |
Collapse
|
45
|
Moreno JC, Tiller N, Diez M, Karcher D, Tillich M, Schöttler MA, Bock R. Generation and characterization of a collection of knock-down lines for the chloroplast Clp protease complex in tobacco. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:2199-2218. [PMID: 28369470 PMCID: PMC5447895 DOI: 10.1093/jxb/erx066] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Protein degradation in chloroplasts is carried out by a set of proteases that eliminate misfolded, damaged, or superfluous proteins. The ATP-dependent caseinolytic protease (Clp) is the most complex protease in plastids and has been implicated mainly in stromal protein degradation. In contrast, FtsH, a thylakoid membrane-associated metalloprotease, is believed to participate mainly in the degradation of thylakoidal proteins. To determine the role of specific Clp and FtsH subunits in plant growth and development, RNAi lines targeting at least one subunit of each Clp ring and FtsH were generated in tobacco. In addition, mutation of the translation initiation codon was employed to down-regulate expression of the plastid-encoded ClpP1 subunit. These protease lines cover a broad range of reductions at the transcript and protein levels of the targeted genes. A wide spectrum of phenotypes was obtained, including pigment deficiency, alterations in leaf development, leaf variegations, and impaired photosynthesis. When knock-down lines for the different protease subunits were compared, both common and specific phenotypes were observed, suggesting distinct functions of at least some subunits. Our work provides a well-characterized collection of knock-down lines for plastid proteases in tobacco and reveals the importance of the Clp protease in physiology and plant development.
Collapse
Affiliation(s)
- Juan C Moreno
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
| | - Nadine Tiller
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
| | - Mercedes Diez
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
| | - Daniel Karcher
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
| | - Michael Tillich
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
| | - 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
|
46
|
Pulido P, Llamas E, Rodriguez-Concepcion M. Both Hsp70 chaperone and Clp protease plastidial systems are required for protection against oxidative stress. PLANT SIGNALING & BEHAVIOR 2017; 12:e1290039. [PMID: 28277974 PMCID: PMC5399908 DOI: 10.1080/15592324.2017.1290039] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 01/26/2017] [Accepted: 01/27/2017] [Indexed: 05/25/2023]
Abstract
Environmental stress conditions such as high light, extreme temperatures, salinity or drought trigger oxidative stress and eventually protein misfolding in plants. In chloroplasts, chaperone systems refold proteins after stress, while proteases degrade misfolded and aggregated proteins that cannot be refolded. We observed that reduced activity of chloroplast Hsp70 chaperone or Clp protease systems both prevented growth of Arabidopsis thaliana seedlings after treatment with the oxidative agent methyl viologen. Besides showing a role for these particular protein quality control components on the protection against oxidative stress, we provide evidence supporting the existence of a yet undiscovered pathway for Clp-mediated degradation of the damaged proteins.
Collapse
Affiliation(s)
- Pablo Pulido
- Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Campus UAB Bellaterra, Barcelona, Spain
| | - Ernesto Llamas
- Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Campus UAB Bellaterra, Barcelona, Spain
| | - Manuel Rodriguez-Concepcion
- Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Campus UAB Bellaterra, Barcelona, Spain
| |
Collapse
|
47
|
Romanowska E, Buczyńska A, Wasilewska W, Krupnik T, Drożak A, Rogowski P, Parys E, Zienkiewicz M. Differences in photosynthetic responses of NADP-ME type C4 species to high light. PLANTA 2017; 245:641-657. [PMID: 27990574 PMCID: PMC5310562 DOI: 10.1007/s00425-016-2632-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 09/20/2016] [Indexed: 05/22/2023]
Abstract
MAIN CONCLUSION Three species chosen as representatives of NADP-ME C4 subtype exhibit different sensitivity toward photoinhibition, and great photochemical differences were found to exist between the species. These characteristics might be due to the imbalance in the excitation energy between the photosystems present in M and BS cells, and also due to that between species caused by the penetration of light inside the leaves. Such regulation in the distribution of light intensity between M and BS cells shows that co-operation between both the metabolic systems determines effective photosynthesis and reduces the harmful effects of high light on the degradation of PSII through the production of reactive oxygen species (ROS). We have investigated several physiological parameters of NADP-ME-type C4 species (e.g., Zea mays, Echinochloa crus-galli, and Digitaria sanguinalis) grown under moderate light intensity (200 µmol photons m-2 s-1) and, subsequently, exposed to excess light intensity (HL, 1600 µmol photons m-2 s-1). Our main interest was to understand why these species, grown under identical conditions, differ in their responses toward high light, and what is the physiological significance of these differences. Among the investigated species, Echinochloa crus-galli is best adapted to HL treatment. High resistance of the photosynthetic apparatus of E. crus-galli to HL was accompanied by an elevated level of phosphorylation of PSII proteins, and higher values of photochemical quenching, ATP/ADP ratio, activity of PSI and PSII complexes, as well as integrity of the thylakoid membranes. It was also shown that the non-radiative dissipation of energy in the studied plants was not dependent on carotenoid contents and, thus, other photoprotective mechanisms might have been engaged under HL stress conditions. The activity of the enzymes superoxide dismutase and ascorbate peroxidase as well as the content of malondialdehyde and H2O2 suggests that antioxidant defense is not responsible for the differences observed in the tolerance of NADP-ME species toward HL stress. We concluded that the chloroplasts of the examined NADP-ME species showed different sensitivity to short-term high light irradiance, suggesting a role of other factors excluding light factors, thus influencing the response of thylakoid proteins. We also observed that HL affects the mesophyll chloroplasts first hand and, subsequently, the bundle sheath chloroplasts.
Collapse
Affiliation(s)
- Elżbieta Romanowska
- Department of Molecular Plant Physiology, Faculty of BiologyUniversity of Warsaw, Miecznikowa 1, 02-096, Warsaw, Poland.
| | - Alicja Buczyńska
- Department of Molecular Plant Physiology, Faculty of BiologyUniversity of Warsaw, Miecznikowa 1, 02-096, Warsaw, Poland
| | - Wioleta Wasilewska
- Department of Molecular Plant Physiology, Faculty of BiologyUniversity of Warsaw, Miecznikowa 1, 02-096, Warsaw, Poland
| | - Tomasz Krupnik
- Department of Molecular Plant Physiology, Faculty of BiologyUniversity of Warsaw, Miecznikowa 1, 02-096, Warsaw, Poland
| | - Anna Drożak
- Department of Molecular Plant Physiology, Faculty of BiologyUniversity of Warsaw, Miecznikowa 1, 02-096, Warsaw, Poland
| | - Paweł Rogowski
- Department of Molecular Plant Physiology, Faculty of BiologyUniversity of Warsaw, Miecznikowa 1, 02-096, Warsaw, Poland
| | - Eugeniusz Parys
- Department of Molecular Plant Physiology, Faculty of BiologyUniversity of Warsaw, Miecznikowa 1, 02-096, Warsaw, Poland
| | - Maksymilian Zienkiewicz
- Department of Molecular Plant Physiology, Faculty of BiologyUniversity of Warsaw, Miecznikowa 1, 02-096, Warsaw, Poland
| |
Collapse
|
48
|
Wang F, Qi Y, Malnoë A, Choquet Y, Wollman FA, de Vitry C. The High Light Response and Redox Control of Thylakoid FtsH Protease in Chlamydomonas reinhardtii. MOLECULAR PLANT 2017; 10:99-114. [PMID: 27702692 DOI: 10.1016/j.molp.2016.09.012] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 09/07/2016] [Accepted: 09/17/2016] [Indexed: 05/23/2023]
Abstract
In Chlamydomonas reinhardtii, the major protease involved in the maintenance of photosynthetic machinery in thylakoid membranes, the FtsH protease, mostly forms large hetero-oligomers (∼1 MDa) comprising FtsH1 and FtsH2 subunits, whatever the light intensity for growth. Upon high light exposure, the FtsH subunits display a shorter half-life, which is counterbalanced by an increase in FTSH1/2 mRNA levels, resulting in the modest upregulation of FtsH1/2 proteins. Furthermore, we found that high light increases the protease activity through a hitherto unnoticed redox-controlled reduction of intermolecular disulfide bridges. We isolated a Chlamydomonas FTSH1 promoter-deficient mutant, ftsh1-3, resulting from the insertion of a TOC1 transposon, in which the high light-induced upregulation of FTSH1 gene expression is largely lost. In ftsh1-3, the abundance of FtsH1 and FtsH2 proteins are loosely coupled (decreased by 70% and 30%, respectively) with no formation of large and stable homo-oligomers. Using strains exhibiting different accumulation levels of the FtsH1 subunit after complementation of ftsh1-3, we demonstrate that high light tolerance is tightly correlated with the abundance of the FtsH protease. Thus, the response of Chlamydomonas to light stress involves higher levels of FtsH1/2 subunits associated into large complexes with increased proteolytic activity.
Collapse
Affiliation(s)
- Fei Wang
- Institut de Biologie Physico-Chimique, Unité Mixte de Recherche 7141, Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, Paris 75005, France
| | - Yafei Qi
- Institut de Biologie Physico-Chimique, Unité Mixte de Recherche 7141, Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, Paris 75005, France
| | - Alizée Malnoë
- Institut de Biologie Physico-Chimique, Unité Mixte de Recherche 7141, Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, Paris 75005, France
| | - Yves Choquet
- Institut de Biologie Physico-Chimique, Unité Mixte de Recherche 7141, Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, Paris 75005, France
| | - Francis-André Wollman
- Institut de Biologie Physico-Chimique, Unité Mixte de Recherche 7141, Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, Paris 75005, France
| | - Catherine de Vitry
- Institut de Biologie Physico-Chimique, Unité Mixte de Recherche 7141, Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, Paris 75005, France.
| |
Collapse
|
49
|
Nishimura K, Kato Y, Sakamoto W. Essentials of Proteolytic Machineries in Chloroplasts. MOLECULAR PLANT 2017; 10:4-19. [PMID: 27585878 DOI: 10.1016/j.molp.2016.08.005] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 08/17/2016] [Accepted: 08/21/2016] [Indexed: 05/22/2023]
Abstract
Plastids are unique organelles that can alter their structure and function in response to environmental and developmental stimuli. Chloroplasts are one type of plastid and are the sites for various metabolic processes, including photosynthesis. For optimal photosynthetic activity, the chloroplast proteome must be properly shaped and maintained through regulated proteolysis and protein quality control mechanisms. Enzymatic functions and activities are conferred by protein maturation processes involving consecutive proteolytic reactions. Protein abundances are optimized by the balanced protein synthesis and degradation, which is depending on the metabolic status. Malfunctioning proteins are promptly degraded. Twenty chloroplast proteolytic machineries have been characterized to date. Specifically, processing peptidases and energy-driven processive proteases are the major players in chloroplast proteome biogenesis, remodeling, and maintenance. Recently identified putative proteases are potential regulators of photosynthetic functions. Here we provide an updated, comprehensive overview of chloroplast protein degradation machineries and discuss their importance for photosynthesis. Wherever possible, we also provide structural insights into chloroplast proteases that implement regulated proteolysis of substrate proteins/peptides.
Collapse
Affiliation(s)
- Kenji Nishimura
- Institute of Plant Science and Resources, Okayama University, 2-20-1 Chuo, Kurashiki, Okayama 710-0046, Japan
| | - Yusuke Kato
- Institute of Plant Science and Resources, Okayama University, 2-20-1 Chuo, Kurashiki, Okayama 710-0046, Japan
| | - Wataru Sakamoto
- Institute of Plant Science and Resources, Okayama University, 2-20-1 Chuo, Kurashiki, Okayama 710-0046, Japan.
| |
Collapse
|
50
|
Thagela P, Yadav RK, Mishra V, Dahuja A, Ahmad A, Singh PK, Tiwari BS, Abraham G. Salinity-induced inhibition of growth in the aquatic pteridophyte Azolla microphylla primarily involves inhibition of photosynthetic components and signaling molecules as revealed by proteome analysis. PROTOPLASMA 2017; 254:303-313. [PMID: 26837223 DOI: 10.1007/s00709-016-0946-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 01/18/2016] [Indexed: 05/21/2023]
Abstract
Salinity stress causes adverse physiological and biochemical changes in the growth and productivity of a plant. Azolla, a symbiotic pteridophyte and potent candidate for biofertilizer due to its nitrogen fixation ability, shows reduced growth and nitrogen fixation during saline stress. To better understand regulatory components involved in salinity-induced physiological changes, in the present study, Azolla microphylla plants were exposed to NaCl (6.74 and 8.61 ds/m) and growth, photochemical reactions of photosynthesis, ion accumulation, and changes in cellular proteome were studied. Maximum dry weight was accumulated in control and untreated plant while a substantial decrease in dry weight was observed in the plants exposed to salinity. Exposure of the organism to different concentrations of salt in hydroponic conditions resulted in differential level of Na+ and K+ ion accumulation. Comparative analysis of salinity-induced proteome changes in A. microphylla revealed 58 salt responsive proteins which were differentially expressed during the salt exposure. Moreover, 42 % spots among differentially expressed proteins were involved in different signaling events. The identified proteins are involved in photosynthesis, energy metabolism, amino acid biosynthesis, protein synthesis, and defense. Downregulation of these key metabolic proteins appears to inhibit the growth of A. microphylla in response to salinity. Altogether, the study revealed that in Azolla, increased salinity primarily affected signaling and photosynthesis that in turn leads to reduced biomass.
Collapse
Affiliation(s)
- Preeti Thagela
- Centre for Conservation and Utilization of BGA, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Ravindra Kumar Yadav
- Centre for Conservation and Utilization of BGA, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Vagish Mishra
- NRCPB, ICAR-Indian Agricultural Research Institute, Pusa Campus, New Delhi, 110012, India
| | - Anil Dahuja
- Division of Biochemistry, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Altaf Ahmad
- Department of Botany, Aligarh Muslim University, Aligarh, U.P., India
| | - Pawan Kumar Singh
- Department of Botany, Banaras Hindu University, Varanasi, 221005, U.P., India
| | - Budhi Sagar Tiwari
- School of Biological Sciences and Biotechnology, University and Institute of Advanced Research, Gandhinagar, 382007, Gujrat, India
| | - Gerard Abraham
- Centre for Conservation and Utilization of BGA, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India.
- Centre for Conservation and Utilization of BGA, CCUBGA, NEAR AUDITORIUM, New Delhi, 110012, India.
| |
Collapse
|