1
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Huo Y, Cheng M, Tang M, Zhang M, Yang X, Zheng Y, Zhao T, He P, Yu J. GhCTSF1, a short PPR protein with a conserved role in chloroplast development and photosynthesis, participates in intron splicing of rpoC1 and ycf3-2 transcripts in cotton. PLANT COMMUNICATIONS 2024; 5:100858. [PMID: 38444162 PMCID: PMC11211521 DOI: 10.1016/j.xplc.2024.100858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Revised: 02/29/2024] [Accepted: 03/04/2024] [Indexed: 03/07/2024]
Abstract
Cotton is one of the most important textile fibers worldwide. As crucial agronomic traits, leaves play an essential role in the growth, disease resistance, fiber quality, and yield of cotton plants. Pentatricopeptide repeat (PPR) proteins are a large family of nuclear-encoded proteins involved in organellar or nuclear RNA metabolism. Using a virus-induced gene silencing assay, we found that cotton plants displayed variegated yellow leaf phenotypes with decreased chlorophyll content when expression of the PPR gene GhCTSF1 was silenced. GhCTSF1 encodes a chloroplast-localized protein that contains only two PPR motifs. Disruption of GhCTSF1 substantially reduces the splicing efficiency of rpoC1 intron 1 and ycf3 intron 2. Loss of function of the GhCTSF1 ortholog EMB1417 causes splicing defects in rpoC1 and ycf3-2, leading to impaired chloroplast structure and decreased photosynthetic rates in Arabidopsis. We also found that GhCTSF1 interacts with two splicing factors, GhCRS2 and GhWTF1. Defects in GhCRS2 and GhWTF1 severely affect intron splicing of rpoC1 and ycf3-2 in cotton, leading to defects in chloroplast development and a reduction in photosynthesis. Our results suggest that GhCTSF1 is specifically required for splicing rpoC1 and ycf3-2 in cooperation with GhCRS2 and GhWTF1.
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Affiliation(s)
- Yuzhu Huo
- College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China
| | - Mengxue Cheng
- College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China
| | - Meiju Tang
- College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China
| | - Meng Zhang
- College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China
| | - Xiaofan Yang
- College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China
| | - Yating Zheng
- College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China
| | - Tong Zhao
- College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China
| | - Peng He
- College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China.
| | - Jianing Yu
- College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China.
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2
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Niaz M, Zhang L, Lv G, Hu H, Yang X, Cheng Y, Zheng Y, Zhang B, Yan X, Htun A, Zhao L, Sun C, Zhang N, Ren Y, Chen F. Identification of TaGL1-B1 gene controlling grain length through regulation of jasmonic acid in common wheat. PLANT BIOTECHNOLOGY JOURNAL 2023; 21:979-989. [PMID: 36650924 PMCID: PMC10106860 DOI: 10.1111/pbi.14009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 12/15/2022] [Accepted: 01/06/2023] [Indexed: 05/04/2023]
Abstract
Grain length is one of the most important factors in determining wheat yield. Here, a stable QTL for grain length was mapped on chromosome 1B in a F10 recombinant inbred lines (RIL) population, and the gene TaGL1-B1 encoding carotenoid isomerase was identified in a secondary large population through multiple strategies. The genome-wide association study (GWAS) in 243 wheat accessions revealed that the marker for TaGL1-B1 was the most significant among all chromosomes. EMS mutants of TaGL1 possessed significantly reduced grain length, whereas TaGL1-B1-overexpressed lines possessed significantly increased grain length. Moreover, TaGL1-B1 strongly interacted with TaPAP6. TaPAP6-overexpressed lines had significantly increased grain length. Transcriptome analysis suggested that TaPAP6 was possibly involved in the accumulation of JA (jasmonic acid). Consistently, JA content was significantly increased in the TaGL1-B1 and TaPAP6 overexpression lines. Additionally, the role of TaGL1-B1 in regulating carotenoids was verified through QTL mapping, GWAS, EMS mutants and overexpression lines. Notably, overexpression of TaGL1-B1 significantly increased wheat yield in multiple locations. Taken together, overexpression of TaGL1-B1 enhanced grain length, probably through interaction with TaPAP6 to cause the accumulation of JA that improved carotenoid content and photosynthesis, thereby resulted in increased wheat yield. This study provided valuable genes controlling grain length to improve yield and a potential insight into the molecular mechanism of modulating JA-mediated grain size in wheat.
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Affiliation(s)
- Mohsin Niaz
- National Key Laboratory of Wheat and Maize Crop Science, CIMMYT‐China Wheat and Maize Joint Research Center, Agronomy CollegeHenan Agricultural UniversityZhengzhouChina
| | - Lingran Zhang
- National Key Laboratory of Wheat and Maize Crop Science, CIMMYT‐China Wheat and Maize Joint Research Center, Agronomy CollegeHenan Agricultural UniversityZhengzhouChina
| | - Guoguo Lv
- National Key Laboratory of Wheat and Maize Crop Science, CIMMYT‐China Wheat and Maize Joint Research Center, Agronomy CollegeHenan Agricultural UniversityZhengzhouChina
| | - Huiting Hu
- National Key Laboratory of Wheat and Maize Crop Science, CIMMYT‐China Wheat and Maize Joint Research Center, Agronomy CollegeHenan Agricultural UniversityZhengzhouChina
| | - Xi Yang
- National Key Laboratory of Wheat and Maize Crop Science, CIMMYT‐China Wheat and Maize Joint Research Center, Agronomy CollegeHenan Agricultural UniversityZhengzhouChina
| | - Yongzhen Cheng
- National Key Laboratory of Wheat and Maize Crop Science, CIMMYT‐China Wheat and Maize Joint Research Center, Agronomy CollegeHenan Agricultural UniversityZhengzhouChina
| | - Yueting Zheng
- National Key Laboratory of Wheat and Maize Crop Science, CIMMYT‐China Wheat and Maize Joint Research Center, Agronomy CollegeHenan Agricultural UniversityZhengzhouChina
| | - Bingyang Zhang
- National Key Laboratory of Wheat and Maize Crop Science, CIMMYT‐China Wheat and Maize Joint Research Center, Agronomy CollegeHenan Agricultural UniversityZhengzhouChina
| | - Xiangning Yan
- National Key Laboratory of Wheat and Maize Crop Science, CIMMYT‐China Wheat and Maize Joint Research Center, Agronomy CollegeHenan Agricultural UniversityZhengzhouChina
| | - Aye Htun
- National Key Laboratory of Wheat and Maize Crop Science, CIMMYT‐China Wheat and Maize Joint Research Center, Agronomy CollegeHenan Agricultural UniversityZhengzhouChina
| | - Lei Zhao
- National Key Laboratory of Wheat and Maize Crop Science, CIMMYT‐China Wheat and Maize Joint Research Center, Agronomy CollegeHenan Agricultural UniversityZhengzhouChina
| | - Congwei Sun
- National Key Laboratory of Wheat and Maize Crop Science, CIMMYT‐China Wheat and Maize Joint Research Center, Agronomy CollegeHenan Agricultural UniversityZhengzhouChina
| | - Ning Zhang
- National Key Laboratory of Wheat and Maize Crop Science, CIMMYT‐China Wheat and Maize Joint Research Center, Agronomy CollegeHenan Agricultural UniversityZhengzhouChina
| | - Yan Ren
- National Key Laboratory of Wheat and Maize Crop Science, CIMMYT‐China Wheat and Maize Joint Research Center, Agronomy CollegeHenan Agricultural UniversityZhengzhouChina
| | - Feng Chen
- National Key Laboratory of Wheat and Maize Crop Science, CIMMYT‐China Wheat and Maize Joint Research Center, Agronomy CollegeHenan Agricultural UniversityZhengzhouChina
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Espinoza-Corral R, Herrera-Tequia A, Lundquist PK. Insights into topology and membrane interaction characteristics of plastoglobule-localized AtFBN1a and AtLOX2. PLANT SIGNALING & BEHAVIOR 2021; 16:1945213. [PMID: 34180346 PMCID: PMC8330992 DOI: 10.1080/15592324.2021.1945213] [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] [Indexed: 05/04/2023]
Abstract
Plant chloroplasts harbor ubiquitous lipid droplets called plastoglobules. While physically connected to the thylakoid membrane, they are characterized by a unique set of about 30 proteins specifically associated with the plastoglobule. How these proteins selectively target the plastoglobule remains unknown. Protease shaving assays with isolated Arabidopsis thaliana thylakoid and plastoglobule show that a ca. 25 kD portion of the abundant structural protein of plastoglobules, Fibrillin 1a, is protected from protease digestion. Mapping of protease cleavage sites and experimentally identified phosphorylation sites onto a homology model of Fibrillin 1a indicates that this protected sequence corresponds to the C-terminal lipocalin-like domain, implicated in specific lipid binding. In contrast, protease shaving and membrane washing assays with another plastoglobule-associated protein harboring a C-terminal PLAT domain, Lipoxygenase 2, is consistent with an exposed PLAT domain positioned parallel with, and upon, the surface of the plastoglobule. We propose a model where conserved lipid-binding domains associate with either the surface or neutral core of the lipid droplet. Our study provides insight into the topology and membrane interactions of two plastoglobule-localized proteins.
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Affiliation(s)
- Roberto Espinoza-Corral
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI, USA
- The Plant Resilience Institute, Michigan State University, East Lansing, MI, USA
| | - Andres Herrera-Tequia
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI, USA
- The Plant Resilience Institute, Michigan State University, East Lansing, MI, USA
| | - Peter K. Lundquist
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI, USA
- The Plant Resilience Institute, Michigan State University, East Lansing, MI, USA
- CONTACT Peter K. Lundquist Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI, 48824USA
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4
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Li J, Li X, Khatab AA, Xie G. Phylogeny, structural diversity and genome-wide expression analysis of fibrillin family genes in rice. PHYTOCHEMISTRY 2020; 175:112377. [PMID: 32315840 DOI: 10.1016/j.phytochem.2020.112377] [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: 07/22/2019] [Revised: 04/07/2020] [Accepted: 04/08/2020] [Indexed: 06/11/2023]
Abstract
Fibrillins (FBNs) constitute a plastid-lipid-associated protein family that plays a role in chloroplast development, lipids metabolism and stress responses in plants. Until now, FBNs have been functionally characterized in stability of thylakoid and responses to the different stress stimuli. Consequently, phylogeny, domain composition and structural features of 121 FBNs family proteins from ten representative species have been identified. As results, phylogenetic analysis demonstrated that FBNs proteins were grouped into 24 clades and further subdivided into three groups, including terrestrial plant-specific, algae-specific, and intermediate group. These FBNs genes had different numbers of introns and exons but encoded the conserved N-terminal chloroplast transport peptide (CTP) domains and plastid lipid-associated protein (PAP) domains, which greatly contributed to the sub-functionalization and neo-functionalization. Meanwhile, the CTP domains of eleven OsFBN proteins except OsFBN8 could help them transport into chloroplasts. The PAP domains of OsFBN2 and OsFBN4 showed the in vitro specific binding activity to C12-C22 fatty acids that were affected by YxD motif. The qRT-PCR analysis showed that OsFBN genes were differentially induced by heat stress and cold stress in rice. Collectively, this study has provided the new insights into the evolution, structure, and functions of FBN gene family and will help to elucidate the molecular mechanisms of these proteins functioning in growth, development and adaptations in the global climate change.
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Affiliation(s)
- Jiajia Li
- MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Huazhong Agricultural University, Wuhan, 430070, China; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China.
| | - Xukai Li
- College of Life Sciences, Shanxi Agricultural University, Taigu, Shanxi, 030801, China.
| | - Ahmed Adel Khatab
- MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Huazhong Agricultural University, Wuhan, 430070, China; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China; Rice Research and Training Center, Field Crops Research Institute, Agricultural Research Center, Giza, Egypt.
| | - Guosheng Xie
- MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Huazhong Agricultural University, Wuhan, 430070, China; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China.
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5
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Lundquist PK, Shivaiah KK, Espinoza-Corral R. Lipid droplets throughout the evolutionary tree. Prog Lipid Res 2020; 78:101029. [PMID: 32348789 DOI: 10.1016/j.plipres.2020.101029] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Revised: 04/11/2020] [Accepted: 04/18/2020] [Indexed: 12/11/2022]
Abstract
Intracellular lipid droplets are utilized for lipid storage and metabolism in organisms as evolutionarily diverse as animals, fungi, plants, bacteria, and archaea. These lipid droplets demonstrate great diversity in biological functions and protein and lipid compositions, yet fundamentally share common molecular and ultrastructural characteristics. Lipid droplet research has been largely fragmented across the diversity of lipid droplet classes and sub-classes. However, we suggest that there is great potential benefit to the lipid community in better integrating the lipid droplet research fields. To facilitate such integration, we survey the protein and lipid compositions, functional roles, and mechanisms of biogenesis across the breadth of lipid droplets studied throughout the natural world. We depict the big picture of lipid droplet biology, emphasizing shared characteristics and unique differences seen between different classes. In presenting the known diversity of lipid droplets side-by-side it becomes necessary to offer for the first time a consistent system of categorization and nomenclature. We propose a division into three primary classes that reflect their sub-cellular location: i) cytoplasmic lipid droplets (CYTO-LDs), that are present in the eukaryotic cytoplasm, ii) prokaryotic lipid droplets (PRO-LDs), that exist in the prokaryotic cytoplasm, and iii) plastid lipid droplets (PL-LDs), that are found in plant plastids, organelles of photosynthetic eukaryotes. Within each class there is a remarkable array of sub-classes displaying various sizes, shapes and compositions. A more integrated lipid droplet research field will provide opportunities to better build on discoveries and accelerate the pace of research in ways that have not been possible.
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Affiliation(s)
- Peter K Lundquist
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI 48824, USA; Plant Resilience Institute, Michigan State University, East Lansing, MI, 48824, USA.
| | - Kiran-Kumar Shivaiah
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI 48824, USA; Plant Resilience Institute, Michigan State University, East Lansing, MI, 48824, USA
| | - Roberto Espinoza-Corral
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI 48824, USA; Plant Resilience Institute, Michigan State University, East Lansing, MI, 48824, USA
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6
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Espinoza-Corral R, Heinz S, Klingl A, Jahns P, Lehmann M, Meurer J, Nickelsen J, Soll J, Schwenkert S. Plastoglobular protein 18 is involved in chloroplast function and thylakoid formation. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:3981-3993. [PMID: 30976809 PMCID: PMC6685665 DOI: 10.1093/jxb/erz177] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Accepted: 04/02/2019] [Indexed: 05/05/2023]
Abstract
Plastoglobules are lipoprotein particles that are found in different types of plastids. They contain a very specific and specialized set of lipids and proteins. Plastoglobules are highly dynamic in size and shape, and are therefore thought to participate in adaptation processes during either abiotic or biotic stresses or transitions between developmental stages. They are suggested to function in thylakoid biogenesis, isoprenoid metabolism, and chlorophyll degradation. While several plastoglobular proteins contain identifiable domains, others provide no structural clues to their function. In this study, we investigate the role of plastoglobular protein 18 (PG18), which is conserved from cyanobacteria to higher plants. Analysis of a PG18 loss-of-function mutant in Arabidopsis thaliana demonstrated that PG18 plays an important role in thylakoid formation; the loss of PG18 results in impaired accumulation, assembly, and function of thylakoid membrane complexes. Interestingly, the mutant accumulated less chlorophyll and carotenoids, whereas xanthophyll cycle pigments were increased. Accumulation of photosynthetic complexes is similarly affected in both a Synechocystis and an Arabidopsis PG18 mutant. However, the ultrastructure of cyanobacterial thylakoids is not compromised by the lack of PG18, probably due to its less complex architecture.
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Affiliation(s)
- Roberto Espinoza-Corral
- Department Biologie I, Botanik, Ludwig-Maximilians-Universität, Planegg-Martinsried, Germany
| | - Steffen Heinz
- Department Biologie I, Botanik, Ludwig-Maximilians-Universität, Planegg-Martinsried, Germany
| | - Andreas Klingl
- Department Biologie I, Botanik, Ludwig-Maximilians-Universität, Planegg-Martinsried, Germany
| | - Peter Jahns
- Plant Biochemistry, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Martin Lehmann
- Department Biologie I, Botanik, Ludwig-Maximilians-Universität, Planegg-Martinsried, Germany
| | - Jörg Meurer
- Department Biologie I, Botanik, Ludwig-Maximilians-Universität, Planegg-Martinsried, Germany
| | - Jörg Nickelsen
- Department Biologie I, Botanik, Ludwig-Maximilians-Universität, Planegg-Martinsried, Germany
| | - Jürgen Soll
- Department Biologie I, Botanik, Ludwig-Maximilians-Universität, Planegg-Martinsried, Germany
- Munich Center for Integrated Protein Science CiPSM, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Serena Schwenkert
- Department Biologie I, Botanik, Ludwig-Maximilians-Universität, Planegg-Martinsried, Germany
- Correspondence:
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Zhao C, Kim Y, Zeng Y, Li M, Wang X, Hu C, Gorman C, Dai SY, Ding SY, Yuan JS. Co-Compartmentation of Terpene Biosynthesis and Storage via Synthetic Droplet. ACS Synth Biol 2018; 7:774-781. [PMID: 29439563 DOI: 10.1021/acssynbio.7b00368] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Traditional bioproduct engineering focuses on pathway optimization, yet is often complicated by product inhibition, downstream consumption, and the toxicity of certain products. Here, we present the co-compartmentation of biosynthesis and storage via a synthetic droplet as an effective new strategy to improve the bioproduct yield, with squalene as a model compound. A hydrophobic protein was designed and introduced into the tobacco chloroplast to generate a synthetic droplet for terpene storage. Simultaneously, squalene biosynthesis enzymes were introduced to chloroplasts together with the droplet-forming protein to co-compartmentalize the biosynthesis and storage of squalene. The strategy has enabled a record yield of squalene at 2.6 mg/g fresh weight without compromising plant growth. Confocal fluorescent microscopy imaging, stimulated Raman scattering microscopy, and droplet composition analysis confirmed the formation of synthetic storage droplet in chloroplast. The co-compartmentation of synthetic storage droplet with a targeted metabolic pathway engineering represents a new strategy for enhancing bioproduct yield.
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Affiliation(s)
- Cheng Zhao
- Texas A&M Agrilife Synthetic and Systems Biology Innovation Hub , Texas A&M University , College Station , Texas 77843 , United States
- Department of Plant Pathology and Microbiology , Texas A&M University , College Station , Texas 77843 , United States
- Institute for Plant Genomics and Biotechnology , Texas A&M University , College Station , Texas 77843 , United States
| | - YongKyoung Kim
- Texas A&M Agrilife Synthetic and Systems Biology Innovation Hub , Texas A&M University , College Station , Texas 77843 , United States
- Department of Plant Pathology and Microbiology , Texas A&M University , College Station , Texas 77843 , United States
- Institute for Plant Genomics and Biotechnology , Texas A&M University , College Station , Texas 77843 , United States
| | - Yining Zeng
- Biosciences Center , National Renewable Energy Laboratory , Golden , Colorado 80401 , United States
| | - Man Li
- Texas A&M Agrilife Synthetic and Systems Biology Innovation Hub , Texas A&M University , College Station , Texas 77843 , United States
- Department of Plant Pathology and Microbiology , Texas A&M University , College Station , Texas 77843 , United States
- Institute for Plant Genomics and Biotechnology , Texas A&M University , College Station , Texas 77843 , United States
| | - Xin Wang
- Texas A&M Agrilife Synthetic and Systems Biology Innovation Hub , Texas A&M University , College Station , Texas 77843 , United States
- Department of Plant Pathology and Microbiology , Texas A&M University , College Station , Texas 77843 , United States
- Institute for Plant Genomics and Biotechnology , Texas A&M University , College Station , Texas 77843 , United States
| | - Cheng Hu
- Texas A&M Agrilife Synthetic and Systems Biology Innovation Hub , Texas A&M University , College Station , Texas 77843 , United States
- Department of Plant Pathology and Microbiology , Texas A&M University , College Station , Texas 77843 , United States
- Institute for Plant Genomics and Biotechnology , Texas A&M University , College Station , Texas 77843 , United States
| | - Connor Gorman
- Texas A&M Agrilife Synthetic and Systems Biology Innovation Hub , Texas A&M University , College Station , Texas 77843 , United States
- Department of Plant Pathology and Microbiology , Texas A&M University , College Station , Texas 77843 , United States
- Institute for Plant Genomics and Biotechnology , Texas A&M University , College Station , Texas 77843 , United States
| | - Susie Y Dai
- State Hygienic Lab , University of Iowa , Coralville , Iowa 52241 , United States
| | - Shi-You Ding
- Department of Plant Biology , Michigan State University , East Lansing , Michigan 48824 , United States
| | - Joshua S Yuan
- Texas A&M Agrilife Synthetic and Systems Biology Innovation Hub , Texas A&M University , College Station , Texas 77843 , United States
- Department of Plant Pathology and Microbiology , Texas A&M University , College Station , Texas 77843 , United States
- Institute for Plant Genomics and Biotechnology , Texas A&M University , College Station , Texas 77843 , United States
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8
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van Wijk KJ, Kessler F. Plastoglobuli: Plastid Microcompartments with Integrated Functions in Metabolism, Plastid Developmental Transitions, and Environmental Adaptation. ANNUAL REVIEW OF PLANT BIOLOGY 2017; 68:253-289. [PMID: 28125283 DOI: 10.1146/annurev-arplant-043015-111737] [Citation(s) in RCA: 170] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Plastoglobuli (PGs) are plastid lipoprotein particles surrounded by a membrane lipid monolayer. PGs contain small specialized proteomes and metabolomes. They are present in different plastid types (e.g., chloroplasts, chromoplasts, and elaioplasts) and are dynamic in size and shape in response to abiotic stress or developmental transitions. PGs in chromoplasts are highly enriched in carotenoid esters and enzymes involved in carotenoid metabolism. PGs in chloroplasts are associated with thylakoids and contain ∼30 core proteins (including six ABC1 kinases) as well as additional proteins recruited under specific conditions. Systems analysis has suggested that chloroplast PGs function in metabolism of prenyl lipids (e.g., tocopherols, plastoquinone, and phylloquinone); redox and photosynthetic regulation; plastid biogenesis; and senescence, including recycling of phytol, remobilization of thylakoid lipids, and metabolism of jasmonate. These functionalities contribute to chloroplast PGs' role in responses to stresses such as high light and nitrogen starvation. PGs are thus lipid microcompartments with multiple functions integrated into plastid metabolism, developmental transitions, and environmental adaptation. This review provides an in-depth overview of PG experimental observations, summarizes the present understanding of PG features and functions, and provides a conceptual framework for PG research and the realization of opportunities for crop improvement.
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Affiliation(s)
- Klaas J van Wijk
- Plant Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, New York 14853;
| | - Felix Kessler
- Laboratory of Plant Physiology, University of Neuchâtel, 2000 Neuchâtel, Switzerland;
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9
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Brocard L, Immel F, Coulon D, Esnay N, Tuphile K, Pascal S, Claverol S, Fouillen L, Bessoule JJ, Bréhélin C. Proteomic Analysis of Lipid Droplets from Arabidopsis Aging Leaves Brings New Insight into Their Biogenesis and Functions. FRONTIERS IN PLANT SCIENCE 2017; 8:894. [PMID: 28611809 PMCID: PMC5447075 DOI: 10.3389/fpls.2017.00894] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 05/12/2017] [Indexed: 05/18/2023]
Abstract
Lipid droplets (LDs) are cell compartments specialized for oil storage. Although their role and biogenesis are relatively well documented in seeds, little is known about their composition, structure and function in senescing leaves where they also accumulate. Here, we used a label free quantitative mass spectrometry approach to define the LD proteome of aging Arabidopsis leaves. We found that its composition is highly different from that of seed/cotyledon and identified 28 proteins including 9 enzymes of the secondary metabolism pathways involved in plant defense response. With the exception of the TRIGALACTOSYLDIACYLGLYCEROL2 protein, we did not identify enzymes implicated in lipid metabolism, suggesting that growth of leaf LDs does not occur by local lipid synthesis but rather through contact sites with the endoplasmic reticulum (ER) or other membranes. The two most abundant proteins of the leaf LDs are the CALEOSIN3 and the SMALL RUBBER PARTICLE1 (AtSRP1); both proteins have structural functions and participate in plant response to stress. CALEOSIN3 and AtSRP1 are part of larger protein families, yet no other members were enriched in the LD proteome suggesting a specific role of both proteins in aging leaves. We thus examined the function of AtSRP1 at this developmental stage and found that AtSRP1 modulates the expression of CALEOSIN3 in aging leaves. Furthermore, AtSRP1 overexpression induces the accumulation of triacylglycerol with an unusual composition compared to wild-type. We demonstrate that, although AtSRP1 expression is naturally increased in wild type senescing leaves, its overexpression in senescent transgenic lines induces an over-accumulation of LDs organized in clusters at restricted sites of the ER. Conversely, atsrp1 knock-down mutants displayed fewer but larger LDs. Together our results reveal that the abundancy of AtSRP1 regulates the neo-formation of LDs during senescence. Using electron tomography, we further provide evidence that LDs in leaves share tenuous physical continuity as well as numerous contact sites with the ER membrane. Thus, our data suggest that leaf LDs are functionally distinct from seed LDs and that their biogenesis is strictly controlled by AtSRP1 at restricted sites of the ER.
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Affiliation(s)
- Lysiane Brocard
- Plant Imaging Platform, Bordeaux Imaging Center, UMS 3420 Centre National de la Recherche Scientifique, US4 Institut National de la Santé et de la Recherche Médicale, University of BordeauxBordeaux, France
| | - Françoise Immel
- Laboratory of Membrane Biogenesis, Centre National de la Recherche Scientifique, UMR 5200Villenave d'Ornon, France
- Laboratory of Membrane Biogenesis, University of Bordeaux, UMR 5200Villenave d'Ornon, France
| | - Denis Coulon
- Laboratory of Membrane Biogenesis, Centre National de la Recherche Scientifique, UMR 5200Villenave d'Ornon, France
- Laboratory of Membrane Biogenesis, University of Bordeaux, UMR 5200Villenave d'Ornon, France
- Bordeaux INPTalence, France
| | - Nicolas Esnay
- Laboratory of Membrane Biogenesis, Centre National de la Recherche Scientifique, UMR 5200Villenave d'Ornon, France
- Laboratory of Membrane Biogenesis, University of Bordeaux, UMR 5200Villenave d'Ornon, France
| | - Karine Tuphile
- Laboratory of Membrane Biogenesis, Centre National de la Recherche Scientifique, UMR 5200Villenave d'Ornon, France
- Laboratory of Membrane Biogenesis, University of Bordeaux, UMR 5200Villenave d'Ornon, France
| | - Stéphanie Pascal
- Laboratory of Membrane Biogenesis, Centre National de la Recherche Scientifique, UMR 5200Villenave d'Ornon, France
- Laboratory of Membrane Biogenesis, University of Bordeaux, UMR 5200Villenave d'Ornon, France
| | - Stéphane Claverol
- Proteome Platform, Functional Genomic Center of Bordeaux, University of BordeauxBordeaux, France
| | - Laëtitia Fouillen
- Laboratory of Membrane Biogenesis, Centre National de la Recherche Scientifique, UMR 5200Villenave d'Ornon, France
- Laboratory of Membrane Biogenesis, University of Bordeaux, UMR 5200Villenave d'Ornon, France
| | - Jean-Jacques Bessoule
- Laboratory of Membrane Biogenesis, Centre National de la Recherche Scientifique, UMR 5200Villenave d'Ornon, France
- Laboratory of Membrane Biogenesis, University of Bordeaux, UMR 5200Villenave d'Ornon, France
| | - Claire Bréhélin
- Laboratory of Membrane Biogenesis, Centre National de la Recherche Scientifique, UMR 5200Villenave d'Ornon, France
- Laboratory of Membrane Biogenesis, University of Bordeaux, UMR 5200Villenave d'Ornon, France
- *Correspondence: Claire Bréhélin
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10
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You MK, Kim JH, Lee YJ, Jeong YS, Ha SH. Plastoglobule-Targeting Competence of a Putative Transit Peptide Sequence from Rice Phytoene Synthase 2 in Plastids. Int J Mol Sci 2016; 18:ijms18010018. [PMID: 28025520 PMCID: PMC5297653 DOI: 10.3390/ijms18010018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 12/08/2016] [Accepted: 12/14/2016] [Indexed: 11/16/2022] Open
Abstract
Plastoglobules (PGs) are thylakoid membrane microdomains within plastids that are known as specialized locations of carotenogenesis. Three rice phytoene synthase proteins (OsPSYs) involved in carotenoid biosynthesis have been identified. Here, the N-terminal 80-amino-acid portion of OsPSY2 (PTp) was demonstrated to be a chloroplast-targeting peptide by displaying cytosolic localization of OsPSY2(ΔPTp):mCherry in rice protoplast, in contrast to chloroplast localization of OsPSY2:mCherry in a punctate pattern. The peptide sequence of a PTp was predicted to harbor two transmembrane domains eligible for a putative PG-targeting signal. To assess and enhance the PG-targeting ability of PTp, the original PTp DNA sequence (PTp) was modified to a synthetic DNA sequence (stPTp), which had 84.4% similarity to the original sequence. The motivation of this modification was to reduce the GC ratio from 75% to 65% and to disentangle the hairpin loop structures of PTp. These two DNA sequences were fused to the sequence of the synthetic green fluorescent protein (sGFP) and drove GFP expression with different efficiencies. In particular, the RNA and protein levels of stPTp-sGFP were slightly improved to 1.4-fold and 1.3-fold more than those of sGFP, respectively. The green fluorescent signals of their mature proteins were all observed as speckle-like patterns with slightly blurred stromal signals in chloroplasts. These discrete green speckles of PTp-sGFP and stPTp-sGFP corresponded exactly to the red fluorescent signal displayed by OsPSY2:mCherry in both etiolated and greening protoplasts and it is presumed to correspond to distinct PGs. In conclusion, we identified PTp as a transit peptide sequence facilitating preferential translocation of foreign proteins to PGs, and developed an improved PTp sequence, a stPTp, which is expected to be very useful for applications in plant biotechnologies requiring precise micro-compartmental localization in plastids.
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Affiliation(s)
- Min Kyoung You
- Department of Genetic Engineering and Graduate School of Biotechnology, College of Life Sciences, Kyung Hee University, Yongin-si 17104, Korea.
- Crop Biotech Institute, Kyung Hee University, Yongin-si 17104, Korea.
| | - Jin Hwa Kim
- Crop Biotech Institute, Kyung Hee University, Yongin-si 17104, Korea.
| | - Yeo Jin Lee
- Department of Genetic Engineering and Graduate School of Biotechnology, College of Life Sciences, Kyung Hee University, Yongin-si 17104, Korea.
- Crop Biotech Institute, Kyung Hee University, Yongin-si 17104, Korea.
| | - Ye Sol Jeong
- Crop Biotech Institute, Kyung Hee University, Yongin-si 17104, Korea.
| | - Sun-Hwa Ha
- Department of Genetic Engineering and Graduate School of Biotechnology, College of Life Sciences, Kyung Hee University, Yongin-si 17104, Korea.
- Crop Biotech Institute, Kyung Hee University, Yongin-si 17104, Korea.
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11
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Ahrazem O, Gómez-Gómez L, Rodrigo MJ, Avalos J, Limón MC. Carotenoid Cleavage Oxygenases from Microbes and Photosynthetic Organisms: Features and Functions. Int J Mol Sci 2016; 17:E1781. [PMID: 27792173 PMCID: PMC5133782 DOI: 10.3390/ijms17111781] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 10/07/2016] [Accepted: 10/08/2016] [Indexed: 11/17/2022] Open
Abstract
Apocarotenoids are carotenoid-derived compounds widespread in all major taxonomic groups, where they play important roles in different physiological processes. In addition, apocarotenoids include compounds with high economic value in food and cosmetics industries. Apocarotenoid biosynthesis starts with the action of carotenoid cleavage dioxygenases (CCDs), a family of non-heme iron enzymes that catalyze the oxidative cleavage of carbon-carbon double bonds in carotenoid backbones through a similar molecular mechanism, generating aldehyde or ketone groups in the cleaving ends. From the identification of the first CCD enzyme in plants, an increasing number of CCDs have been identified in many other species, including microorganisms, proving to be a ubiquitously distributed and evolutionarily conserved enzymatic family. This review focuses on CCDs from plants, algae, fungi, and bacteria, describing recent progress in their functions and regulatory mechanisms in relation to the different roles played by the apocarotenoids in these organisms.
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Affiliation(s)
- Oussama Ahrazem
- Instituto Botánico, Departamento de Ciencia y Tecnología Agroforestal y Genética, Facultad de Farmacia, Universidad de Castilla-La Mancha, Campus Universitario s/n, 02071 Albacete, Spain.
| | - Lourdes Gómez-Gómez
- Instituto Botánico, Departamento de Ciencia y Tecnología Agroforestal y Genética, Facultad de Farmacia, Universidad de Castilla-La Mancha, Campus Universitario s/n, 02071 Albacete, Spain.
| | - María J Rodrigo
- Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Departamento de Ciencia de los Alimentos, Calle Catedrático Agustín Escardino 7, 46980 Paterna, Spain.
| | - Javier Avalos
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Avenida Reina Mercedes 6, 41012 Sevilla, Spain.
| | - María Carmen Limón
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Avenida Reina Mercedes 6, 41012 Sevilla, Spain.
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12
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Manara A, DalCorso G, Furini A. The Role of the Atypical Kinases ABC1K7 and ABC1K8 in Abscisic Acid Responses. FRONTIERS IN PLANT SCIENCE 2016; 7:366. [PMID: 27047531 PMCID: PMC4805650 DOI: 10.3389/fpls.2016.00366] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 03/09/2016] [Indexed: 05/10/2023]
Abstract
The ABC1K family of atypical kinases (activity of bc1 complex kinase) is represented in bacteria, archaea, and eukaryotes. In plants they regulate diverse physiological processes in the chloroplasts and mitochondria, but their precise functions are poorly defined. ABC1K7 and ABC1K8 are probably involved in oxidative stress responses, isoprenyl lipid synthesis and distribution of iron within chloroplasts. Because reactive oxygen species take part in abscisic acid (ABA)-mediated processes, we investigated the functions of ABC1K7 and ABC1K8 during germination, stomatal movement, and leaf senescence. Both genes were upregulated by ABA treatment and some ABA-responsive physiological processes were affected in abc1k7 and abc1k8 mutants. Germination was more severely affected by ABA, osmotic stress and salt stress in the single and double mutants; the stomatal aperture was smaller in the mutants under standard growth conditions and was not further reduced by exogenous ABA application; ABA-induced senescence symptoms were more severe in the leaves of the single and double mutants compared to wild type leaves. Taken together, our results suggest that ABC1K7 and ABC1K8 might be involved in the cross-talk between ABA and ROS signaling.
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13
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Perello C, Llamas E, Burlat V, Ortiz-Alcaide M, Phillips MA, Pulido P, Rodriguez-Concepcion M. Differential Subplastidial Localization and Turnover of Enzymes Involved in Isoprenoid Biosynthesis in Chloroplasts. PLoS One 2016; 11:e0150539. [PMID: 26919668 PMCID: PMC4769067 DOI: 10.1371/journal.pone.0150539] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 02/15/2016] [Indexed: 11/23/2022] Open
Abstract
Plastidial isoprenoids are a diverse group of metabolites with roles in photosynthesis, growth regulation, and interaction with the environment. The methylerythritol 4-phosphate (MEP) pathway produces the metabolic precursors of all types of plastidial isoprenoids. Proteomics studies in Arabidopsis thaliana have shown that all the enzymes of the MEP pathway are localized in the plastid stroma. However, immunoblot analysis of chloroplast subfractions showed that the first two enzymes of the pathway, deoxyxylulose 5-phosphate synthase (DXS) and reductoisomerase (DXR), can also be found in non-stromal fractions. Both transient and stable expression of GFP-tagged DXS and DXR proteins confirmed the presence of the fusion proteins in distinct subplastidial compartments. In particular, DXR-GFP was found to accumulate in relatively large vesicles that could eventually be released from chloroplasts, presumably to be degraded by an autophagy-independent process. Together, we propose that protein-specific mechanisms control the localization and turnover of the first two enzymes of the MEP pathway in Arabidopsis chloroplasts.
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Affiliation(s)
- Catalina Perello
- Program of Plant Metabolism and Metabolic Engineering, Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Campus UAB Bellaterra, 08193 Barcelona, Spain
| | - Ernesto Llamas
- Program of Plant Metabolism and Metabolic Engineering, Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Campus UAB Bellaterra, 08193 Barcelona, Spain
| | - Vincent Burlat
- Université de Toulouse, CNRS, UMR 5546, BP 42617 Auzeville, 31326 Castanet-Tolosan, France
| | - Miriam Ortiz-Alcaide
- Program of Plant Metabolism and Metabolic Engineering, Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Campus UAB Bellaterra, 08193 Barcelona, Spain
| | - Michael A. Phillips
- Program of Plant Metabolism and Metabolic Engineering, Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Campus UAB Bellaterra, 08193 Barcelona, Spain
| | - Pablo Pulido
- Program of Plant Metabolism and Metabolic Engineering, Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Campus UAB Bellaterra, 08193 Barcelona, Spain
| | - Manuel Rodriguez-Concepcion
- Program of Plant Metabolism and Metabolic Engineering, Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Campus UAB Bellaterra, 08193 Barcelona, Spain
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14
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Abstract
Fundamentally, oil bodies are discrete storage organelles found in oilseeds, comprising a hydrophobic triacylglycerol core surrounded by a half-unit phospholipid membrane and an outer shell of specialized proteins known as oleosins. Oil bodies possess a number of attributes that were exploited by SemBioSys Genetics to isolate highly enriched fractions of oil bodies through liquid-liquid phase separation for a number of commercial applications. The current chapter provides a general guide for the isolation of oil bodies from Arabidopsis and/or safflower seed, from which protocols can be refined for different oilseed sources. For SemBioSys Genetic's recombinant technology, therapeutic proteins were covalently attached to oleosins or fused in-frame with ligands which bound oil bodies, facilitating their recovery to high levels of purity during "upstream processing" of transformed seed. Core to this technology was oil body isolation consisting of simple manipulation including homogenization of seeds to free the oil bodies, followed by the removal of insoluble fractions, and phase separation to recover the oil bodies. During oil body enrichment (an increase in oil body content concomitant with removal of impurities), a number of options and tips are provided to aid researchers in the manipulation and monitoring of these robust organelles.
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Affiliation(s)
- Cory L Nykiforuk
- SemBioSys Genetics Inc., 110 2985 23rd Avenue N.E., Calgary, AB, Canada, T1Y 7L3.
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15
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Rottet S, Besagni C, Kessler F. The role of plastoglobules in thylakoid lipid remodeling during plant development. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1847:889-99. [PMID: 25667966 DOI: 10.1016/j.bbabio.2015.02.002] [Citation(s) in RCA: 99] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Revised: 01/30/2015] [Accepted: 02/03/2015] [Indexed: 12/16/2022]
Abstract
Photosynthesis is the key bioenergetic process taking place in the chloroplast. The components of the photosynthetic machinery are embedded in a highly dynamic matrix, the thylakoid membrane. This membrane has the capacity to adapt during developmental transitions and under stress conditions. The galactolipids are the major polar lipid components of the thylakoid membrane conferring bilayer properties, while neutral thylakoid lipids such as the prenyllipids and carotenoids contribute to essential functions such as electron transport and photoprotection. Despite a large number of studies, the intriguing processes of thylakoid membrane biogenesis and dynamics remain unsolved. Plastoglobules, thylakoid-associated lipid droplets, appear to actively participate in thylakoid function from biogenesis to senescence. Recruitment of specific proteins enables the plastoglobules to act in metabolite synthesis, repair and disposal under changing environmental conditions and developmental stages. In this review, we describe plastoglobules as thylakoid membrane microdomains and discuss their involvement in lipid remodeling during stress and in the conversion from one plastid type to another. This article is part of a Special Issue entitled: Chloroplast Biogenesis.
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Affiliation(s)
- Sarah Rottet
- Laboratory of Plant Physiology, University of Neuchâtel, 2000 Neuchâtel, Switzerland
| | - Céline Besagni
- Laboratory of Plant Physiology, University of Neuchâtel, 2000 Neuchâtel, Switzerland
| | - Felix Kessler
- Laboratory of Plant Physiology, University of Neuchâtel, 2000 Neuchâtel, Switzerland.
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16
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Wang S, Blumwald E. Stress-induced chloroplast degradation in Arabidopsis is regulated via a process independent of autophagy and senescence-associated vacuoles. THE PLANT CELL 2014; 26:4875-88. [PMID: 25538186 PMCID: PMC4311210 DOI: 10.1105/tpc.114.133116] [Citation(s) in RCA: 111] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 11/14/2014] [Accepted: 12/07/2014] [Indexed: 05/18/2023]
Abstract
Two well-known pathways for the degradation of chloroplast proteins are via autophagy and senescence-associated vacuoles. Here, we describe a third pathway that was activated by senescence- and abiotic stress-induced expression of Arabidopsis thaliana CV (for chloroplast vesiculation). After targeting to the chloroplast, CV destabilized the chloroplast, inducing the formation of vesicles. CV-containing vesicles carrying stromal proteins, envelope membrane proteins, and thylakoid membrane proteins were released from the chloroplasts and mobilized to the vacuole for proteolysis. Overexpression of CV caused chloroplast degradation and premature leaf senescence, whereas silencing CV delayed chloroplast turnover and senescence induced by abiotic stress. Transgenic CV-silenced plants displayed enhanced tolerance to drought, salinity, and oxidative stress. Immunoprecipitation and bimolecular fluorescence complementation assays demonstrated that CV interacted with photosystem II subunit PsbO1 in vivo through a C-terminal domain that is highly conserved in the plant kingdom. Collectively, our work indicated that CV plays a crucial role in stress-induced chloroplast disruption and mediates a third pathway for chloroplast degradation. From a biotechnological perspective, silencing of CV offers a suitable strategy for the generation of transgenic crops with increased tolerance to abiotic stress.
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Affiliation(s)
- Songhu Wang
- Department of Plant Sciences, University of California, Davis, California 95616 Chengdu Institute of Biology, Chinese Academy of Science, Chengdu, Sichuan 610041, China
| | - Eduardo Blumwald
- Department of Plant Sciences, University of California, Davis, California 95616
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17
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Arabidopsis thalianaplastoglobule-associated fibrillin 1a interacts with fibrillin 1b in vivo. FEBS Lett 2014; 588:2800-4. [DOI: 10.1016/j.febslet.2014.06.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Accepted: 06/03/2014] [Indexed: 01/18/2023]
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18
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Manara A, DalCorso G, Leister D, Jahns P, Baldan B, Furini A. AtSIA1 AND AtOSA1: two Abc1 proteins involved in oxidative stress responses and iron distribution within chloroplasts. THE NEW PHYTOLOGIST 2014; 201:452-465. [PMID: 24117441 DOI: 10.1111/nph.12533] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Accepted: 08/27/2013] [Indexed: 05/25/2023]
Abstract
The Abc1 protein kinases are a large family of functionally diverse proteins with multiple roles in the regulation of respiration and oxidative stress tolerance. A functional characterization was carried out for AtSIA1, an Arabidopsis thaliana Abc1-like protein, focusing on its potential redundancy with its homolog AtOSA1. Both proteins are located within chloroplasts, even if a different subplastidial localization seems probable. The comparison of atsia1 and atosa1 mutants, atsia1/atosa1 double mutant and wild-type plants revealed a reduction in plastidial iron-containing proteins of the Cytb6 f complex in the mutants. Iron uptake from soil is not hampered in mutant lines, suggesting that AtSIA1 and AtOSA1 affect iron distribution within the chloroplast. Mutants accumulated more ferritin and superoxide, and showed reduced tolerance to reactive oxygen species (ROS), potentially indicating a basal role in oxidative stress. The mutants produced higher concentrations of plastochromanol and plastoquinones than wild-type plants, but only atsia1 plants developed larger plastoglobules and contained higher concentrations of α- and γ-tocopherol and VTE1. Taken together, these data suggest that AtSIA1 and AtOSA1 probably act in signaling pathways that influence responses to ROS production and oxidative stress.
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Affiliation(s)
- Anna Manara
- Dipartimento di Biotecnologie, Università degli Studi di Verona, Strada Le Grazie 15, Verona, Italy
| | - Giovanni DalCorso
- Dipartimento di Biotecnologie, Università degli Studi di Verona, Strada Le Grazie 15, Verona, Italy
| | - Dario Leister
- Dept Biologie I, Botanik, Biozentrum der LMU München, Großhaderner Str. 2-4, Planegg-Martinsried, Germany
| | - Peter Jahns
- Heinrich-Heine-Universität Biochemie der Pflanzen, Universitätsstraße 1, Düsseldorf, Germany
| | - Barbara Baldan
- Dipartimento di Biologia, Università degli Studi di Padova, Via Ugo Bassi, 58/B, Padova, Italy
| | - Antonella Furini
- Dipartimento di Biotecnologie, Università degli Studi di Verona, Strada Le Grazie 15, Verona, Italy
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19
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Shanmugabalaji V, Kessler F. Gradient Flotation Centrifugation of Chloroplast Membranes. Bio Protoc 2014. [DOI: 10.21769/bioprotoc.1230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
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20
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Abstract
Prenylquinones are indispensable molecules in plants and animals. In plants, phylloquinone (vitamin K) and plastoquinone are electron carriers during photosynthesis in chloroplasts, whereas tocopherol (vitamin E) functions as a lipid antioxidant. The biosynthetic pathways of the prenylquinones have been largely characterized but the mechanisms regulating their production and distribution in various subcompartments of the chloroplast are only starting to emerge. Research on chloroplast lipid droplets (plastoglobules) has unraveled a complex network of intersecting prenylquinone metabolic pathways that are providing unprecedented insight into the regulatory processes. In this chapter, we describe how to isolate chloroplast membrane fractions, in particular the plastoglobule lipid droplets, and how to profile the prenylquinones that are contained in these fractions.
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Affiliation(s)
- Felix Kessler
- Laboratory of Plant Physiology, University of Neuchâtel, Neuchâtel, Switzerland
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21
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Abstract
Plant regulatory circuits coordinating nuclear and plastid gene expression have evolved in response to external stimuli. RNA editing is one of such control mechanisms. We determined the Arabidopsis nuclear-encoded homeodomain-containing protein OCP3 is incorporated into the chloroplast, and contributes to control over the extent of ndhB transcript editing. ndhB encodes the B subunit of the chloroplast NADH dehydrogenase-like complex (NDH) involved in cyclic electron flow (CEF) around photosystem I. In ocp3 mutant strains, ndhB editing efficiency decays, CEF is impaired and disease resistance to fungal pathogens substantially enhanced, a process recapitulated in plants defective in editing plastid RNAs encoding NDH complex subunits due to mutations in previously described nuclear-encoded pentatricopeptide-related proteins (i.e. CRR21, CRR2). Furthermore, we observed that following a pathogenic challenge, wild type plants respond with editing inhibition of ndhB transcript. In parallel, rapid destabilization of the plastidial NDH complex is also observed in the plant following perception of a pathogenic cue. Therefore, NDH complex activity and plant immunity appear as interlinked processes.
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22
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Shanmugabalaji V, Besagni C, Piller LE, Douet V, Ruf S, Bock R, Kessler F. Dual targeting of a mature plastoglobulin/fibrillin fusion protein to chloroplast plastoglobules and thylakoids in transplastomic tobacco plants. PLANT MOLECULAR BIOLOGY 2013; 81:13-25. [PMID: 23086498 DOI: 10.1007/s11103-012-9977-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Accepted: 10/08/2012] [Indexed: 05/10/2023]
Abstract
Plastoglobules (PG) are lipid droplets in chloroplasts and other plastid types having important functions in lipid metabolism. Plastoglobulins (PGL) also known as fibrillins (FBN) are evolutionary conserved proteins present at the PG surface but also to various extents at the thylakoid membrane. PGLs are thought to have structural functions in PG formation and maintenance. The targeting of an Arabidopsis PGL (PGL34) to PG required the full protein sequence with the exception of a short C-terminal stretch. This indicated that PGL targeting relies on correct folding rather than a discrete sequence. PGLs lack strongly hydrophic regions and may therefore extrinsically associate with PG and thylakoid membranes via interaction with hydrophilic headgroups of surface lipids. Here, we report on the expression of the Arabidopsis plastoglobulin of 35kD (PGL35 or FBN1a) expressed as a mature protein fused to HIVp24 (human immunodeficiency virus capsid particle p24) or HCV (hepatitis C virus core protein) in transplastomic tobacco. A PGL35-HIVp24 fusion targeted in part to plastoglobules but a larger proportion was recovered in the thylakoid fraction. The findings indicate that transplastomic PGL35-HIVp24 folded correctly after its synthesis inside the chloroplast and then dually targeted to plastoglobules as well as thylakoid membranes.
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23
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Nacir H, Bréhélin C. When proteomics reveals unsuspected roles: the plastoglobule example. FRONTIERS IN PLANT SCIENCE 2013; 4:114. [PMID: 23630540 PMCID: PMC3635846 DOI: 10.3389/fpls.2013.00114] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Accepted: 04/11/2013] [Indexed: 05/18/2023]
Abstract
Plastoglobules are globular compartments found in plastids. Before initial proteomic studies were published, these particles were often viewed as passive lipid droplets whose unique role was to store lipids coming from the thylakoid turn-over, or to accumulate carotenoids in the chromoplasts. Yet, two proteomic studies, published concomitantly, suggested for the first time that plastoglobules are more than "junk cupboards" for lipids. Indeed, both studies demonstrated that plastoglobules do not only include structural proteins belonging to the plastoglobulin/fibrillin family, but also contain active enzymes. The specific plastoglobule localization of these enzymes has been confirmed by different approaches such as immunogold localization and GFP protein fusions, thus providing evidence that plastoglobules actively participate in diverse pathways of plastid metabolism. These proteomic studies have been the basis for numerous recent works investigating plastoglobule function. However, a lot still needs to be discovered about the molecular composition and the role of plastoglobules. In this chapter, we will describe how the proteomic approaches have launched new perspectives on plastoglobule functions.
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Affiliation(s)
- Houda Nacir
- Laboratoire de Biogenèse Membranaire, CNRSVillenave d’Ornon, France
- Laboratoire de Biogenèse Membranaire, Université de BordeauxVillenave d’Ornon, France
| | - Claire Bréhélin
- Laboratoire de Biogenèse Membranaire, CNRSVillenave d’Ornon, France
- Laboratoire de Biogenèse Membranaire, Université de BordeauxVillenave d’Ornon, France
- *Correspondence: Claire Bréhélin, Laboratoire de Biogenèse Membranaire, CNRS – Université de Bordeaux, UMR5200, Campus INRA de Bordeaux, 71 Avenue E. Bourlaux, BP 81, F-33883 Villenave d’Ornon Cedex, France. e-mail:
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24
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Shumskaya M, Bradbury LM, Monaco RR, Wurtzel ET. Plastid localization of the key carotenoid enzyme phytoene synthase is altered by isozyme, allelic variation, and activity. THE PLANT CELL 2012; 24:3725-41. [PMID: 23023170 PMCID: PMC3480298 DOI: 10.1105/tpc.112.104174] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Revised: 08/16/2012] [Accepted: 09/05/2012] [Indexed: 05/18/2023]
Abstract
Plant carotenoids have unique physiological roles related to specific plastid suborganellar locations. Carotenoid metabolic engineering could enhance plant adaptation to climate change and improve food security and nutritional value. However, lack of fundamental knowledge on carotenoid pathway localization limits targeted engineering. Phytoene synthase (PSY), a major rate-controlling carotenoid enzyme, is represented by multiple isozymes residing at unknown plastid sites. In maize (Zea mays), the three isozymes were transiently expressed and found either in plastoglobuli or in stroma and thylakoid membranes. PSY1, with one to two residue modifications of naturally occurring functional variants, exhibited altered localization, associated with distorted plastid shape and formation of a fibril phenotype. Mutating the active site of the enzyme reversed this phenotype. Discovery of differential PSY locations, linked with activity and isozyme type, advances the engineering potential for modifying carotenoid biosynthesis.
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Affiliation(s)
- Maria Shumskaya
- Department of Biological Sciences, Lehman College, City University of New York, Bronx, New York, 10468
| | - Louis M.T. Bradbury
- Department of Biological Sciences, Lehman College, City University of New York, Bronx, New York, 10468
| | - Regina R. Monaco
- Department of Biological Sciences, Lehman College, City University of New York, Bronx, New York, 10468
| | - Eleanore T. Wurtzel
- Department of Biological Sciences, Lehman College, City University of New York, Bronx, New York, 10468
- Graduate School and University Center, City University of New York, New York, New York 10016-4309
- Address correspondence to
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25
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Murphy DJ. The dynamic roles of intracellular lipid droplets: from archaea to mammals. PROTOPLASMA 2012; 249:541-85. [PMID: 22002710 DOI: 10.1007/s00709-011-0329-7] [Citation(s) in RCA: 170] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2011] [Accepted: 09/28/2011] [Indexed: 05/02/2023]
Abstract
During the past decade, there has been a paradigm shift in our understanding of the roles of intracellular lipid droplets (LDs). New genetic, biochemical and imaging technologies have underpinned these advances, which are revealing much new information about these dynamic organelles. This review takes a comparative approach by examining recent work on LDs across the whole range of biological organisms from archaea and bacteria, through yeast and Drosophila to mammals, including humans. LDs probably evolved originally in microorganisms as temporary stores of excess dietary lipid that was surplus to the immediate requirements of membrane formation/turnover. LDs then acquired roles as long-term carbon stores that enabled organisms to survive episodic lack of nutrients. In multicellular organisms, LDs went on to acquire numerous additional roles including cell- and organism-level lipid homeostasis, protein sequestration, membrane trafficking and signalling. Many pathogens of plants and animals subvert their host LD metabolism as part of their infection process. Finally, malfunctions in LDs and associated proteins are implicated in several degenerative diseases of modern humans, among the most serious of which is the increasingly prevalent constellation of pathologies, such as obesity and insulin resistance, which is associated with metabolic syndrome.
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Affiliation(s)
- Denis J Murphy
- Division of Biological Sciences, University of Glamorgan, Cardiff, CF37 4AT, UK.
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Organelle transformation. Methods Mol Biol 2012. [PMID: 22610643 DOI: 10.1007/978-1-61779-818-4_29] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
The source of genetic information in a plant cell is contained in nucleus, plastids, and mitochondria. Organelle transformation is getting a lot of attention nowadays because of its superior performance over the conventional and most commonly used nuclear transformation for obtaining transgenic lines. Absence of gene silencing, strong predictable transgene expression, and its application in molecular pharming, both in pharmaceutical and nutraceuticals, are some of many advantages. Other important benefits of utilizing this technology include the absence of transgene flow, as organelles are maternally inherited. This may increase the acceptability of organelle transformation technology in the development of transgenic crops in a wider scale all over the globe. As the need for crop productivity and therapeutic compounds increases, organelle transformation may be able to bridge the gap, thereby having a definite promise for the future.
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Lundquist PK, Poliakov A, Bhuiyan NH, Zybailov B, Sun Q, van Wijk KJ. The functional network of the Arabidopsis plastoglobule proteome based on quantitative proteomics and genome-wide coexpression analysis. PLANT PHYSIOLOGY 2012; 158:1172-92. [PMID: 22274653 PMCID: PMC3291262 DOI: 10.1104/pp.111.193144] [Citation(s) in RCA: 151] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2011] [Accepted: 01/19/2012] [Indexed: 05/18/2023]
Abstract
Plastoglobules (PGs) in chloroplasts are thylakoid-associated monolayer lipoprotein particles containing prenyl and neutral lipids and several dozen proteins mostly with unknown functions. An integrated view of the role of the PG is lacking. Here, we better define the PG proteome and provide a conceptual framework for further studies. The PG proteome from Arabidopsis (Arabidopsis thaliana) leaf chloroplasts was determined by mass spectrometry of isolated PGs and quantitative comparison with the proteomes of unfractionated leaves, thylakoids, and stroma. Scanning electron microscopy showed the purity and size distribution of the isolated PGs. Compared with previous PG proteome analyses, we excluded several proteins and identified six new PG proteins, including an M48 metallopeptidase and two Absence of bc1 complex (ABC1) atypical kinases, confirmed by immunoblotting. This refined PG proteome consisted of 30 proteins, including six ABC1 kinases and seven fibrillins together comprising more than 70% of the PG protein mass. Other fibrillins were located predominantly in the stroma or thylakoid and not in PGs; we discovered that this partitioning can be predicted by their isoelectric point and hydrophobicity. A genome-wide coexpression network for the PG genes was then constructed from mRNA expression data. This revealed a modular network with four distinct modules that each contained at least one ABC1K and/or fibrillin gene. Each module showed clear enrichment in specific functions, including chlorophyll degradation/senescence, isoprenoid biosynthesis, plastid proteolysis, and redox regulators and phosphoregulators of electron flow. We propose a new testable model for the PGs, in which sets of genes are associated with specific PG functions.
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Affiliation(s)
- Peter K. Lundquist
- Department of Plant Biology (P.K.L., A.P., N.H.B., B.Z., K.J.v.W.) and Computational Biology Service Unit (Q.S.), Cornell University, Ithaca, New York 14853
| | - Anton Poliakov
- Department of Plant Biology (P.K.L., A.P., N.H.B., B.Z., K.J.v.W.) and Computational Biology Service Unit (Q.S.), Cornell University, Ithaca, New York 14853
| | - Nazmul H. Bhuiyan
- Department of Plant Biology (P.K.L., A.P., N.H.B., B.Z., K.J.v.W.) and Computational Biology Service Unit (Q.S.), Cornell University, Ithaca, New York 14853
| | | | - Qi Sun
- Department of Plant Biology (P.K.L., A.P., N.H.B., B.Z., K.J.v.W.) and Computational Biology Service Unit (Q.S.), Cornell University, Ithaca, New York 14853
| | - Klaas J. van Wijk
- Department of Plant Biology (P.K.L., A.P., N.H.B., B.Z., K.J.v.W.) and Computational Biology Service Unit (Q.S.), Cornell University, Ithaca, New York 14853
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Eugeni Piller L, Abraham M, Dörmann P, Kessler F, Besagni C. Plastid lipid droplets at the crossroads of prenylquinone metabolism. JOURNAL OF EXPERIMENTAL BOTANY 2012; 63:1609-18. [PMID: 22371323 DOI: 10.1093/jxb/ers016] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Lipid droplets called plastoglobules (PGs) exist in most plant tissues and plastid types. In chloroplasts, the polar lipid monolayer surrounding these low-density lipoprotein particles is continuous with the outer lipid leaflet of the thylakoid membrane. Often small clusters of two or three PGs, only one of them directly connected to thylakoids, are present. Structural proteins (known as plastid-lipid associated proteins/fibrillins or plastoglobulins) together with lipid metabolic enzymes coat the PGs. The hydrophobic core of PGs contains a range of neutral lipids including the prenylquinones [tocopherols (vitamin E), phylloquinone (vitamin K(1)), and plastoquinone (PQ-9)]. In this review the function of PGs and their associated enzymes in prenylquinone metabolism will be discussed.
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Affiliation(s)
- Lucia Eugeni Piller
- Laboratoire de Physiologie Végétale, Université de Neuchâtel, 2000 Neuchâtel, Switzerland
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Singh DK, McNellis TW. Fibrillin protein function: the tip of the iceberg? TRENDS IN PLANT SCIENCE 2011; 16:432-41. [PMID: 21571574 DOI: 10.1016/j.tplants.2011.03.014] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2011] [Revised: 03/31/2011] [Accepted: 03/31/2011] [Indexed: 05/03/2023]
Abstract
Fibrillins are nuclear-encoded, plastid proteins associated with chromoplast fibrils and chloroplast plastoglobules, thylakoids, photosynthetic antenna complexes, and stroma. There are 12 sub-families of fibrillins. However, only three of these sub-families have been characterized genetically or functionally. We review evidence indicating that fibrillins are involved in plastoglobule structural development, chromoplast pigment accumulation, hormonal responses, protection of the photosynthetic apparatus from photodamage, and plant resistance to a range of biotic and abiotic stresses. The area of fibrillin research has substantial growth potential and will contribute to better understanding of mechanisms of plant stress tolerance and plastid structure and function.
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Affiliation(s)
- Dharmendra K Singh
- Department of Plant Pathology, The Pennsylvania State University, University Park, PA 16802, USA
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Besagni C, Piller LE, Bréhélin C. Preparation of plastoglobules from Arabidopsis plastids for proteomic analysis and other studies. Methods Mol Biol 2011; 775:223-39. [PMID: 21863446 DOI: 10.1007/978-1-61779-237-3_12] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Plastoglobules are particles specifically located inside different types of plastids. They mainly contain lipids and proteins and are physically attached to thylakoids. Proteomic studies have underlined the role of plastoglobules in diverse plastid metabolic pathways, such as those producing vitamin K, vitamin E, and carotenoids, and have implicated them in plant response to stress. This chapter describes the isolation of pure and intact plastoglobules from Arabidopsis leaves. The procedure starts with the isolation of intact chloroplasts by centrifugation on a Percoll gradient. Plastoglobules are then separated from the plastid membranes by flotation on a sucrose gradient. Finally, the purity of the plastoglobule fraction is verified by immunoblotting.
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Affiliation(s)
- Celine Besagni
- Laboratoire de Physiologie Végétale, Université de Neuchâtel, Neuchâtel, Switzerland
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Sharma AK, Sharma MK. Plants as bioreactors: Recent developments and emerging opportunities. Biotechnol Adv 2009; 27:811-832. [PMID: 19576278 PMCID: PMC7125752 DOI: 10.1016/j.biotechadv.2009.06.004] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2009] [Revised: 06/15/2009] [Accepted: 06/16/2009] [Indexed: 12/18/2022]
Abstract
In recent years, the use of plants as bioreactors has emerged as an exciting area of research and significant advances have created new opportunities. The driving forces behind the rapid growth of plant bioreactors include low production cost, product safety and easy scale up. As the yield and concentration of a product is crucial for commercial viability, several strategies have been developed to boost up protein expression in transgenic plants. Augmenting tissue-specific transcription, elevating transcript stability, tissue-specific targeting, translation optimization and sub-cellular accumulation are some of the strategies employed. Various kinds of products that are currently being produced in plants include vaccine antigens, medical diagnostics proteins, industrial and pharmaceutical proteins, nutritional supplements like minerals, vitamins, carbohydrates and biopolymers. A large number of plant-derived recombinant proteins have reached advanced clinical trials. A few of these products have already been introduced in the market.
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Affiliation(s)
- Arun K Sharma
- Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi 110021, India.
| | - Manoj K Sharma
- Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi 110021, India
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33
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Surface plasmon resonance characterization of calspermin–calmodulin binding kinetics. Anal Biochem 2008; 376:61-72. [DOI: 10.1016/j.ab.2008.01.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2007] [Revised: 01/15/2008] [Accepted: 01/16/2008] [Indexed: 12/11/2022]
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Tissot G, Canard H, Nadai M, Martone A, Botterman J, Dubald M. Translocation of aprotinin, a therapeutic protease inhibitor, into the thylakoid lumen of genetically engineered tobacco chloroplasts. PLANT BIOTECHNOLOGY JOURNAL 2008; 6:309-20. [PMID: 18266824 DOI: 10.1111/j.1467-7652.2008.00321.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Aprotinin, a bovine protease inhibitor of important therapeutic value, was expressed in tobacco plastid transformants. This disulphide bond-containing protein was targeted to the lumen of thylakoids using signal peptides derived from nuclear genes which encode lumenal proteins. Translocation was attempted via either the general secretion (Sec) or the twin-arginine translocation (Tat) pathway. In both cases, this strategy allowed the production of genuine aprotinin with its N-terminal arginine residue. The recombinant protease inhibitor was efficiently secreted within the lumen of thylakoids, accumulated in older leaves and was bound to trypsin, suggesting that the three disulphide bonds of aprotinin are correctly folded and paired in this chloroplast compartment. Mass spectrometric analysis indicated that translocation via the Sec pathway, unlike the Tat pathway, led predominantly to an oxidized protein. Translocation via the Tat pathway was linked to a slightly decreased growth rate, a pale-green leaf phenotype and supplementary expression products associated with the thylakoids.
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