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Pasaribu B, Purba NP, Dewanti LP, Pasaribu D, Khan AMA, Harahap SA, Syamsuddin ML, Ihsan YN, Siregar SH, Faizal I, Herawati T, Irfan M, Simorangkir TPH, Kurniawan TA. Lipid Droplets in Endosymbiotic Symbiodiniaceae spp. Associated with Corals. PLANTS (BASEL, SWITZERLAND) 2024; 13:949. [PMID: 38611478 PMCID: PMC11013053 DOI: 10.3390/plants13070949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 03/16/2024] [Accepted: 03/19/2024] [Indexed: 04/14/2024]
Abstract
Symbiodiniaceae species is a dinoflagellate that plays a crucial role in maintaining the symbiotic mutualism of reef-building corals in the ocean. Reef-building corals, as hosts, provide the nutrition and habitat to endosymbiotic Symbiodiniaceae species and Symbiodiniaceae species transfer the fixed carbon to the corals for growth. Environmental stress is one of the factors impacting the physiology and metabolism of the corals-dinoflagellate association. The environmental stress triggers the metabolic changes in Symbiodiniaceae species resulting in an increase in the production of survival organelles related to storage components such as lipid droplets (LD). LDs are found as unique organelles, mainly composed of triacylglycerols surrounded by phospholipids embedded with some proteins. To date, it has been reported that investigation of lipid droplets significantly present in animals and plants led to the understanding that lipid droplets play a key role in lipid storage and transport. The major challenge of investigating endosymbiotic Symbiodiniaceae species lies in overcoming the strategies in isolating lesser lipid droplets present in its intercellular cells. Here, we review the most recent highlights of LD research in endosymbiotic Symbiodiniaceae species particularly focusing on LD biogenesis, mechanism, and major lipid droplet proteins. Moreover, to comprehend potential novel ways of energy storage in the symbiotic interaction between endosymbiotic Symbiodiniaceae species and its host, we also emphasize recent emerging environmental factors such as temperature, ocean acidification, and nutrient impacting the accumulation of lipid droplets in endosymbiotic Symbiodiniaceae species.
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Affiliation(s)
- Buntora Pasaribu
- Department of Marine Science, Faculty of Fisheries and Marine Science, Universitas Padjadjaran, Bandung 40600, Indonesia; (N.P.P.); (S.A.H.); (M.L.S.); (Y.N.I.); (I.F.)
- Shallow Coastal and Aquatic Research Forensic (SCARF) Laboratory, Faculty of Fishery and Marine Science, Universitas Padjadjaran, Bandung 40600, Indonesia
- Department of Plant Biology and Pathology, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA;
| | - Noir Primadona Purba
- Department of Marine Science, Faculty of Fisheries and Marine Science, Universitas Padjadjaran, Bandung 40600, Indonesia; (N.P.P.); (S.A.H.); (M.L.S.); (Y.N.I.); (I.F.)
| | - Lantun Paradhita Dewanti
- Department of Fisheries, Faculty of Fisheries and Marine Science, Universitas Padjadjaran, Bandung 40600, Indonesia;
| | - Daniel Pasaribu
- Faculty of Law, Social, and Political Sciences, Universitas Terbuka, Tangerang 15437, Indonesia;
| | - Alexander Muhammad Akbar Khan
- Tropical Marine Fisheries Undergraduate Programme for Pangandaran Campus, Faculty of Fisheries and Marine Science, Universitas Padjadjaran, Bandung 40600, Indonesia;
| | - Syawaludin Alisyahbana Harahap
- Department of Marine Science, Faculty of Fisheries and Marine Science, Universitas Padjadjaran, Bandung 40600, Indonesia; (N.P.P.); (S.A.H.); (M.L.S.); (Y.N.I.); (I.F.)
| | - Mega Laksmini Syamsuddin
- Department of Marine Science, Faculty of Fisheries and Marine Science, Universitas Padjadjaran, Bandung 40600, Indonesia; (N.P.P.); (S.A.H.); (M.L.S.); (Y.N.I.); (I.F.)
| | - Yudi Nurul Ihsan
- Department of Marine Science, Faculty of Fisheries and Marine Science, Universitas Padjadjaran, Bandung 40600, Indonesia; (N.P.P.); (S.A.H.); (M.L.S.); (Y.N.I.); (I.F.)
| | - Sofyan Husein Siregar
- Department of Marine Science, Faculty of Fisheries and Marine Science, Universitas Riau, Pekanbaru 28291, Indonesia;
| | - Ibnu Faizal
- Department of Marine Science, Faculty of Fisheries and Marine Science, Universitas Padjadjaran, Bandung 40600, Indonesia; (N.P.P.); (S.A.H.); (M.L.S.); (Y.N.I.); (I.F.)
| | - Titin Herawati
- Department of Plant Biology and Pathology, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA;
- Master Program of Marine Conservation, Faculty of Fisheries and Marine Science, Universitas Padjadjaran, Bandung 40600, Indonesia
| | - Mohammad Irfan
- Plant Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY 14850, USA;
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Chen K, Yin Y, Ding Y, Chao H, Li M. Characterization of Oil Body and Starch Granule Dynamics in Developing Seeds of Brassica napus. Int J Mol Sci 2023; 24:ijms24044201. [PMID: 36835614 PMCID: PMC9967339 DOI: 10.3390/ijms24044201] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 02/10/2023] [Accepted: 02/14/2023] [Indexed: 02/22/2023] Open
Abstract
Brassica napus is the most important oilseed crop in the world, and the lipid was stored in the oil body (OB) in the form of triacylglycerol. At present, most of studies on the relationship between oil body morphology and seed oil content in B. napus was focused on mature seeds. In the present study, the OBs in different developing seeds of B. napus with relatively high oil content (HOC) of about 50% and low oil content (LOC) of about 39% were analyzed. It was revealed that the size of OBs was first increased and then decreased in both materials. And in late seed developmental stages, the average OB size of rapeseed with HOC was higher than that of LOC, while it was reversed in the early seed developmental stages. No significant difference was observed on starch granule (SG) size in HOC and LOC rapeseed. Further results indicated that the expression of genes that involved in malonyl-CoA metabolism, fatty acid carbon chain extension, lipid metabolism, and starch synthesis in the rapeseed with HOC was higher than that of rapeseed with LOC. These results give some new insight for understanding the dynamics of OBs and SGs in embryos of B. napus.
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Affiliation(s)
- Kang Chen
- Department of Biotechnology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
- Key Laboratory of Molecular Biophysics of the Ministry of Education, Wuhan 430074, China
| | - Yongtai Yin
- Department of Biotechnology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
- Key Laboratory of Molecular Biophysics of the Ministry of Education, Wuhan 430074, China
| | - Yiran Ding
- Department of Biotechnology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
- Key Laboratory of Molecular Biophysics of the Ministry of Education, Wuhan 430074, China
| | - Hongbo Chao
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China
| | - Maoteng Li
- Department of Biotechnology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
- Key Laboratory of Molecular Biophysics of the Ministry of Education, Wuhan 430074, China
- Correspondence:
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A computational study on the structure-function relationships of plant caleosins. Sci Rep 2023; 13:72. [PMID: 36593238 PMCID: PMC9807586 DOI: 10.1038/s41598-022-26936-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Accepted: 12/22/2022] [Indexed: 01/03/2023] Open
Abstract
Plant cells store energy in oil bodies constructed by structural proteins such as oleosins and caleosins. Although oil bodies usually accumulate in the seed and pollen of plants, caleosins are present in various organs and organelles. This issue, coupled with the diverse activities of caleosins, complicates the description of these oleo-proteins. Therefore, the current article proposes a new classification based on the bioinformatics analysis of the transmembrane topology of caleosins. Accordingly, the non-membrane class are the most abundant and diverse caleosins, especially in lower plants. Comparing the results with other reports suggests a stress response capacity for these caleosins. However, other classes play a more specific role in germination and pollination. A phylogenetic study also revealed two main clades that were significantly different in terms of caleosin type, expression profile, molecular weight, and isoelectric point (P < 0.01). In addition to the biochemical significance of the findings, predicting the structure of caleosins is necessary for constructing oil bodies used in the food and pharmaceutical industries.
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Hanano A, Perez-Matas E, Shaban M, Cusido RM, Murphy DJ. Characterization of lipid droplets from a Taxus media cell suspension and their potential involvement in trafficking and secretion of paclitaxel. PLANT CELL REPORTS 2022; 41:853-871. [PMID: 34984531 DOI: 10.1007/s00299-021-02823-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Accepted: 12/08/2021] [Indexed: 06/14/2023]
Abstract
Our paper describes the potential roles of lipid droplets of Taxus media cell suspension in the biosynthesis and secretion of paclitaxel and, therefore, highlights their involvement in improving its production. Paclitaxel (PTX) is a highly potent anticancer drug that is mainly produced using Taxus sp. cell suspension cultures. The main purpose of the current study is to characterize cellular LDs from T. media cell suspension with a particular focus on the biological connection of their associated proteins, the caleosins (CLOs), with the biosynthesis and secretion of PTX. A pure LD fraction obtained from T. media cells and characterized in terms of their proteome. Interestingly, the cellular LD in T. media sequester the PTX. This was confirmed in vitro, where about 96% of PTX (C0PTX,aq [mg L-1]) in the aqueous solution was partitioned into the isolated LDs. Furthermore, silencing of CLO-encoding genes in the T. media cells led to a net decrease in the number and size of LDs. This coincided with a significant reduction in expression levels of TXS, DBAT and DBTNBT, key genes in the PTX biosynthesis pathway. Subsequently, the biosynthesis of PTX was declined in cell culture. In contrast, treatment of cells with 13-hydroperoxide C18:3, a substrate of the peroxygenase activity, induced the expression of CLOs, and, therefore, the accumulation of cellular LDs in the T. media cells cultures, thus increasing the PTX secretion. The accumulation of stable LDs is critically important for effective secretion of PTX. This is modulated by the expression of caleosins, a class of LD-associated proteins with a dual role conferring the structural stability of LDs as well as regulating lipidic bioactive metabolites via their enzymatic activity, thus enhancing the biosynthesis of PTX.
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Affiliation(s)
- Abdulsamie Hanano
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria (AECS), P.O. Box 6091, Damascus, Syria.
| | - Edgar Perez-Matas
- Secció de Fisiologia Vegetal, Facultat de Farmacia, Universitat de Barcelona, Av. Joan XXIII Sn., 08028, Barcelona, Spain
| | - Mouhnad Shaban
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria (AECS), P.O. Box 6091, Damascus, Syria
| | - Rosa M Cusido
- Secció de Fisiologia Vegetal, Facultat de Farmacia, Universitat de Barcelona, Av. Joan XXIII Sn., 08028, Barcelona, Spain
| | - Denis J Murphy
- Genomics and Computational Biology Group, University of South Wales, Pontypridd, Wales, UK
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Abstract
INTRODUCTION Allergies affect 20-30% of the population and respiratory allergies are mostly due to pollen grains from anemophilous plants. One to 5% of people suffer from food allergies and clinicians report increasing numbers of pollen-food allergy syndrome (PFAS), such that the symptoms have broadened from respiratory to gastrointestinal, and even to anaphylactic shock in the presence of cofactors. Thirty to 60% of food allergies are associated with pollen allergy while the percentage of pollen allergies associated to food allergy varies according to local environment and dietary habits. AREAS COVERED Articles published in peer-reviewed journals, covered by PubMed databank, clinical data are discussed including symptoms, diagnosis, and management. A chapter emphasizes the role of six well-known allergen families involved in PFAS: PR10 proteins, profilins, lipid transfer proteins, thaumatin-like proteins, isoflavone reductases, and β-1,3 glucanases. The relevance in PFAS of three supplementary allergen families is presented: oleosins, polygalacturonases, and gibberellin-regulated proteins. To support the discussion a few original relevant results were added. EXPERT OPINION Both allergenic sources, pollen and food, are submitted to the same stressful environmental changes resulting in an increase of pathogenesis-related proteins in which numerous allergens are found. This might be responsible for the potential increase of PFAS.
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Affiliation(s)
- Pascal Poncet
- Armand Trousseau Children Hospital, Immunology Department, Allergy & Environment Research Team , Paris, France.,Immunology Department, Institut Pasteur , Paris, France
| | - Hélène Sénéchal
- Armand Trousseau Children Hospital, Immunology Department, Allergy & Environment Research Team , Paris, France
| | - Denis Charpin
- Aix Marseille University and French Clean Air Association (APPA) , Marseille, France
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Hanano A, Shaban M, Murphy DJ. Functional involvement of caleosin/peroxygenase PdPXG4 in the accumulation of date palm leaf lipid droplets after exposure to dioxins. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 281:116966. [PMID: 33799204 DOI: 10.1016/j.envpol.2021.116966] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 03/03/2021] [Accepted: 03/15/2021] [Indexed: 06/12/2023]
Abstract
Dioxins are highly injurious environmental pollutants with proven toxicological effects on both animals and humans, but to date their effects on plants still need to be studied in detail. We identified a dioxin-inducible caleosin/peroxygenase isoform, PdPXG4, that is mostly expressed in leaves of date palm seedlings and exhibits a specific reductase activity towards the 13-hydroperoxide of C18:2 and C18:3 (HpODE and HpOTrE, respectively). After exposure to TCDD, lipid droplets (LDs) isolated from TCDD-exposed leaves were about 6.5-15.7-fold more active in metabolizing 13-HpOTrE compared with those isolated from non-exposed leaves. A characteristic spectrum of leaf dioxin-responsive oxylipins (LDROXYL) was detected in dioxin-exposed seedlings. Of particular importance, a group of these oxylipins, referred to as Class I, comprising six congeners of hydroxides fatty acids derived from C18:2 and C18:3, was exclusively found in leaves after exposure to TCDD. The TCDD-induced oxylipin pattern was confirmed in vitro using terbufos, a typical inhibitor towards the PdPXG4 peroxygenase activity. Of particular interest, the response of terbufos-pretreated protoplasts to TCDD was drastically reduced. Together, these findings suggest that PdPXG4 is implicated in the establishment of a dioxin-specific oxylipin signature in date palm leaves soon after their exposure to these pollutants.
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Affiliation(s)
- Abdulsamie Hanano
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria (AECS), Damascus, Syria.
| | - Mouhnad Shaban
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria (AECS), Damascus, Syria.
| | - Denis J Murphy
- Genomics and Computational Biology Research Group, University of South Wales, NP7 7ET, United Kingdom.
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Structural and interfacial characterization of oil bodies extracted from Camellia oleifera under the neutral and alkaline condition. Lebensm Wiss Technol 2021. [DOI: 10.1016/j.lwt.2021.110911] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Abdullah, Weiss J, Zhang H. Recent advances in the composition, extraction and food applications of plant-derived oleosomes. Trends Food Sci Technol 2020. [DOI: 10.1016/j.tifs.2020.10.029] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Chmielewska A, Kozłowska M, Rachwał D, Wnukowski P, Amarowicz R, Nebesny E, Rosicka-Kaczmarek J. Canola/rapeseed protein - nutritional value, functionality and food application: a review. Crit Rev Food Sci Nutr 2020; 61:3836-3856. [PMID: 32907356 DOI: 10.1080/10408398.2020.1809342] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Plant-based diet and plant proteins specifically are predestined to meet nutritional requirements of growing population of humans and simultaneously reduce negative effects of food production on the environment. While searching for new sources of proteins, special emphasis should be placed on oilseeds of Brassica family comprising varieties of rapeseed and canola as they contain nutritionally valuable proteins, which have potential to be used in food, but are now rarely or not used as food components. The purpose of the present work is to provide a comprehensive review of main canola/rapeseed proteins: cruciferin and napin, with the focus on their nutritional and functional features, putting special emphasis on their possible applications in food. Technological challenges to obtain rapeseed protein products that are free from anti-nutritional factors are also addressed. As molecular structure of cruciferin and napin differs, they exhibit distinct features, such as solubility, emulsifying, foaming or gelling properties. Potential allergenic effect of 2S napin has to be taken under consideration. Overall, rapeseed proteins demonstrate beneficial nutritional value and functional properties and are deemed to play important roles both in food, as well as, non-food and non-feed applications.
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Affiliation(s)
- Anna Chmielewska
- NapiFeryn BioTech Ltd, Lodz, Poland.,Institute of Food Technology and Analysis, Faculty of Biotechnology and Food Sciences, Lodz University of Technology, Lodz, Poland
| | | | | | | | - Ryszard Amarowicz
- NapiFeryn BioTech Ltd, Lodz, Poland.,Institute of Animal Reproduction and Food Research, Polish Academy of Sciences in Olsztyn, Olsztyn, Poland
| | - Ewa Nebesny
- Institute of Food Technology and Analysis, Faculty of Biotechnology and Food Sciences, Lodz University of Technology, Lodz, Poland
| | - Justyna Rosicka-Kaczmarek
- Institute of Food Technology and Analysis, Faculty of Biotechnology and Food Sciences, Lodz University of Technology, Lodz, Poland
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Pasaribu B, Fu JH, Jiang PL. Identification and characterization of caleosin in Cycas revoluta pollen. PLANT SIGNALING & BEHAVIOR 2020; 15:1779486. [PMID: 32552503 PMCID: PMC8570736 DOI: 10.1080/15592324.2020.1779486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Oil bodies are essential energy storage organelles that are generally present in the seeds of plants. Caleosin protein has been identified in the seed oil bodies of Cycas revolutaseed. In this study, mature Cycas revoluta pollen grains were collected from cycad elliptical cones. However, the isolation and identification of oil bodies protein from mature Cycas revoluta grains have never been experimentally determined. Ultrastructural studies have shown that the oil bodies were present in pollen Cycas revoluta grains. Lipid analysis showed that oil bodies are predominantly composed of triacylglycerol. Complete cDNA fragments encoding the caleosin were obtained by PCR cloning. Phylogenetic tree analyzes showed that cycad pollen caleosin is closely related to the caleosin of Cycas revoluta seeds. Fresh Cycas revoluta pollen grains were allowed to germinate for 48 h in a germination medium containing 2% sucrose and 0.01% H3BO3. Pollen germination were recorded periodically from day one to day 10 and the results showed that the Cycas revoluta pollen elongate the tube and increasing of triacylglycerol(TAG) after 4 days.
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Affiliation(s)
- Buntora Pasaribu
- Department of Plant Biology & Pathology, Rutgers University, New Brunswick, USA
| | - Jou-Hsuan Fu
- Department of Biotechnology, National Formosa University, Yunlin, Taiwan
| | - Pei-Luen Jiang
- Department of Biotechnology, National Formosa University, Yunlin, Taiwan
- CONTACT Pei-Luen Jiang Department of Biotechnology, National Formosa University, Yunlin, Taiwan; Buntora Pasaribu Department of Plant Biology & Pathology, Rutgers University, 59 Dudley Road, Rutgers University, New Brunswick, NJ 08901, USA
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The Role of Triacylglycerol in Plant Stress Response. PLANTS 2020; 9:plants9040472. [PMID: 32276473 PMCID: PMC7238164 DOI: 10.3390/plants9040472] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 03/31/2020] [Accepted: 04/02/2020] [Indexed: 12/12/2022]
Abstract
Vegetable oil is mainly composed of triacylglycerol (TAG), a storage lipid that serves as a major commodity for food and industrial purposes, as well as an alternative biofuel source. While TAG is typically not produced at significant levels in vegetative tissues, emerging evidence suggests that its accumulation in such tissues may provide one mechanism by which plants cope with abiotic stress. Different types of abiotic stress induce lipid remodeling through the action of specific lipases, which results in various alterations in membrane lipid composition. This response induces the formation of toxic lipid intermediates that cause membrane damage or cell death. However, increased levels of TAG under stress conditions are believed to function, at least in part, as a means of sequestering these toxic lipid intermediates. Moreover, the lipid droplets (LDs) in which TAG is enclosed also function as a subcellular factory to provide binding sites and substrates for the biosynthesis of bioactive compounds that protect against insects and fungi. Though our knowledge concerning the role of TAG in stress tolerance is expanding, many gaps in our understanding of the mechanisms driving these processes are still evident. In this review, we highlight progress that has been made to decipher the role of TAG in plant stress response, and we discuss possible ways in which this information could be utilized to improve crops in the future.
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Rahman F, Hassan M, Rosli R, Almousally I, Hanano A, Murphy DJ. Evolutionary and genomic analysis of the caleosin/peroxygenase (CLO/PXG) gene/protein families in the Viridiplantae. PLoS One 2018; 13:e0196669. [PMID: 29771926 PMCID: PMC5957377 DOI: 10.1371/journal.pone.0196669] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Accepted: 03/06/2018] [Indexed: 12/04/2022] Open
Abstract
Bioinformatics analyses of caleosin/peroxygenases (CLO/PXG) demonstrated that these genes are present in the vast majority of Viridiplantae taxa for which sequence data are available. Functionally active CLO/PXG proteins with roles in abiotic stress tolerance and lipid droplet storage are present in some Trebouxiophycean and Chlorophycean green algae but are absent from the small number of sequenced Prasinophyceaen genomes. CLO/PXG-like genes are expressed during dehydration stress in Charophyte algae, a sister clade of the land plants (Embryophyta). CLO/PXG-like sequences are also present in all of the >300 sequenced Embryophyte genomes, where some species contain as many as 10–12 genes that have arisen via selective gene duplication. Angiosperm genomes harbour at least one copy each of two distinct CLO/PX isoforms, termed H (high) and L (low), where H-forms contain an additional C-terminal motif of about 30–50 residues that is absent from L-forms. In contrast, species in other Viridiplantae taxa, including green algae, non-vascular plants, ferns and gymnosperms, contain only one (or occasionally both) of these isoforms per genome. Transcriptome and biochemical data show that CLO/PXG-like genes have complex patterns of developmental and tissue-specific expression. CLO/PXG proteins can associate with cytosolic lipid droplets and/or bilayer membranes. Many of the analysed isoforms also have peroxygenase activity and are involved in oxylipin metabolism. The distribution of CLO/PXG-like genes is consistent with an origin >1 billion years ago in at least two of the earliest diverging groups of the Viridiplantae, namely the Chlorophyta and the Streptophyta, after the Viridiplantae had already diverged from other Archaeplastidal groups such as the Rhodophyta and Glaucophyta. While algal CLO/PXGs have roles in lipid packaging and stress responses, the Embryophyte proteins have a much wider spectrum of roles and may have been instrumental in the colonisation of terrestrial habitats and the subsequent diversification as the major land flora.
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Affiliation(s)
- Farzana Rahman
- Genomics and Computational Biology Research Group, University of South Wales, Pontypridd, United Kingdom
| | - Mehedi Hassan
- Genomics and Computational Biology Research Group, University of South Wales, Pontypridd, United Kingdom
| | - Rozana Rosli
- Genomics and Computational Biology Research Group, University of South Wales, Pontypridd, United Kingdom
- Advanced Biotechnology and Breeding Centre, Malaysian Palm Oil Board, Kuala Lumpur, Malaysia
| | - Ibrahem Almousally
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria, Damascus, Syria
| | - Abdulsamie Hanano
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria, Damascus, Syria
| | - Denis J. Murphy
- Genomics and Computational Biology Research Group, University of South Wales, Pontypridd, United Kingdom
- * E-mail:
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