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CUI Z, SHU Y, XIE X, JIN Y. Light-driven activation of NADPH oxidases. SCIENTIA SINICA VITAE 2022. [DOI: 10.1360/ssv-2022-0134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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2
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de Obeso Fernandez del Valle A, Scheckhuber CQ. Superoxide Dismutases in Eukaryotic Microorganisms: Four Case Studies. Antioxidants (Basel) 2022; 11:antiox11020188. [PMID: 35204070 PMCID: PMC8868140 DOI: 10.3390/antiox11020188] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 01/12/2022] [Accepted: 01/16/2022] [Indexed: 01/08/2023] Open
Abstract
Various components in the cell are responsible for maintaining physiological levels of reactive oxygen species (ROS). Several different enzymes exist that can convert or degrade ROS; among them are the superoxide dismutases (SODs). If left unchecked, ROS can cause damage that leads to pathology, can contribute to aging, and may, ultimately, cause death. SODs are responsible for converting superoxide anions to hydrogen peroxide by dismutation. Here we review the role of different SODs on the development and pathogenicity of various eukaryotic microorganisms relevant to human health. These include the fungal aging model, Podospora anserina; various members of the genus Aspergillus that can potentially cause aspergillosis; the agents of diseases such as Chagas and sleeping disease, Trypanosoma cruzi and Trypanosoma brucei, respectively; and, finally, pathogenic amoebae, such as Acanthamoeba spp. In these organisms, SODs fulfill essential and often regulatory functions that come into play during processes such as the development, host infection, propagation, and control of gene expression. We explore the contribution of SODs and their related factors in these microorganisms, which have an established role in health and disease.
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3
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Liu Z, Wu H, Li J, Wang L, Akkaya EU. Naphthalene Endoperoxide Heterodimer Designed for Sustained Singlet Oxygen Release. ACS OMEGA 2021; 6:26799-26804. [PMID: 34661034 PMCID: PMC8515818 DOI: 10.1021/acsomega.1c04518] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 09/24/2021] [Indexed: 06/13/2023]
Abstract
Naphthalene endoperoxides undergo thermal cycloreversion reactions to produce singlet oxygen and their parent naphthalene compounds. The rate of the reaction is dependent on the structural features, such as steric and electronic modulators. We believe that achieving a sustained release rate of singlet oxygen is important in potential biological applications. This can be achieved by tethering of two endoperoxides with different singlet oxygen release rates in a single molecular construct. Here, we report the synthesis of such a dimeric endoperoxide. Our data shows that with the biexponential reaction kinetics of singlet oxygen generation from a heterodimeric endoperoxide, it is possible to hold singlet oxygen release rates within a selected range for a longer period of time.
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Jin R, Baumgart T. Asymmetric desorption of lipid oxidation products induces membrane bending. SOFT MATTER 2021; 17:7506-7515. [PMID: 34338699 PMCID: PMC8425771 DOI: 10.1039/d1sm00652e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Lipid oxidation, detected in metabolic processes, is induced in excess when the cellular membrane suffers extra oxidative stress. Lipid oxidation can compromise biomembrane function in part through perturbations of lipid packing, membrane permeability, and morphology. Two major types of oxidation products, one with a partially truncated lipid tail with a hydrophilic group at the tail-end, and secondly, a lysolipid (with one of the chains completely truncated) can disturb the membrane bilayer packing significantly. However, they also have an increased tendency to desorb from the membrane. In this study we investigated desorption kinetics of two characteristic lipid oxidation products (PAzePC and 18 : 1 LysoPC) from a model membrane system, and we evaluated the consequences of this process on membrane shape transitions. Using a microfluidic chamber coupled with micropipette aspiration, we observed the incorporation of the two lipids into the membrane of a giant unilamellar vesicle (GUV) and further determined their desorption rates, association rates and flip-flop rates. For both lipids, the desorption is on the time scale of seconds, one to two orders of magnitude faster than their flipping rates. Dilution of the outer solution of the GUVs allowed asymmetric desorption of these two lipids from the GUVs. This process induced lipid number asymmetry and charge asymmetry, specifically for PAzePC containing GUVs, and caused membrane tubulation. Our results indicate that the desorption of lipid oxidation products can alter the local structure of biomembranes and result in morphological changes that may relate to membrane function.
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Affiliation(s)
- Rui Jin
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
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5
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Tonon CC, Ashraf S, Alburquerque JQ, de Souza Rastelli AN, Hasan T, Lyons AM, Greer A. Antimicrobial Photodynamic Inactivation Using Topical and Superhydrophobic Sensitizer Techniques: A Perspective from Diffusion in Biofilms †. Photochem Photobiol 2021; 97:1266-1277. [PMID: 34097752 PMCID: PMC10375486 DOI: 10.1111/php.13461] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 06/04/2021] [Indexed: 12/14/2022]
Abstract
This review describes nanoparticle and dye diffusion in bacterial biofilms in the context of antimicrobial photodynamic inactivation (aPDI). aPDI requires the diffusion of a photosensitizer (Sens) into the biofilm and subsequent photoactivation of oxygen for the generation of reactive oxygen species (ROS) that inactivate microbes. Molecular diffusion in biofilms has been long investigated, whereas this review is intended to draw a logical link between diffusion in biofilms and ROS, a combination that leads to the current state of aPDI and superhydrophobic aPDI (SH-aPDI). This review should be of interest to photochemists, photobiologists and researchers in material and antimicrobial sciences as is ties together conventional aPDI with the emerging subject of SH-aPDI.
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Affiliation(s)
- Caroline Coradi Tonon
- Wellman Center for Photomedicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Shoaib Ashraf
- Wellman Center for Photomedicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - José Quílez Alburquerque
- Wellman Center for Photomedicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.,Department of Organic Chemistry, Faculty of Chemistry, Complutense University of Madrid (UCM), Madrid, Spain
| | - Alessandra Nara de Souza Rastelli
- Wellman Center for Photomedicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.,Department of Restorative Dentistry, School of Dentistry, São Paulo State University-UNESP, Araraquara, SP, Brazil
| | - Tayyaba Hasan
- Wellman Center for Photomedicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.,Division of Health Sciences and Technology, Harvard University and Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Alan M Lyons
- Department of Chemistry, College of Staten Island, City University of New York, Staten Island, NY, USA.,Ph.D. Program in Chemistry, The Graduate Center of the City University of New York, New York, NY, USA.,SingletO2 Therapeutics LLC, New York, NY, USA
| | - Alexander Greer
- Ph.D. Program in Chemistry, The Graduate Center of the City University of New York, New York, NY, USA.,SingletO2 Therapeutics LLC, New York, NY, USA.,Department of Chemistry, Brooklyn College, City University of New York, Brooklyn, NY, USA
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6
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Liu M, Ucar E, Liu Z, Wang L, Yang L, Xu J, Akkaya EU. Anticoagulant activity of singlet oxygen released from a water soluble endoperoxide by thermal cycloreversion. RSC Adv 2021; 11:14513-14516. [PMID: 35423982 PMCID: PMC8697772 DOI: 10.1039/d1ra02569d] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 04/09/2021] [Indexed: 12/24/2022] Open
Abstract
Singlet oxygen generated by photosensitization has limited potential in vivo due to light attenuation in tissues. However, controlled chemical generation of this reactive oxygen species is likely to open new therapeutic spaces to explore. The fact that its activity is limited by the rate of cycloreversion reaction and the diffusion distance of the excited state molecular oxygen species, is a clear advantage, considering the serious side effects of off-target anticoagulants. In this work, we present novel 1,4-naphthalene endoperoxides as potential anti-coagulant agents due to thermal release of singlet oxygen. Singlet oxygen generated by the cycloreversion of endoperoxides has anti-coagulant activity.![]()
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Affiliation(s)
- Meina Liu
- State Key Laboratory of Fine Chemicals, Dalian University of Technology 2 Linggong Road 116024 Dalian China .,Department of Pharmaceutical Science, School of Chemical Engineering, Dalian University of Technology 2 Linggong Road 116024 Dalian China
| | - Esma Ucar
- Department of Chemistry, Bilkent University 06800 Ankara Turkey
| | - Ziang Liu
- State Key Laboratory of Fine Chemicals, Dalian University of Technology 2 Linggong Road 116024 Dalian China .,Department of Pharmaceutical Science, School of Chemical Engineering, Dalian University of Technology 2 Linggong Road 116024 Dalian China
| | - Lei Wang
- State Key Laboratory of Fine Chemicals, Dalian University of Technology 2 Linggong Road 116024 Dalian China .,Department of Pharmaceutical Science, School of Chemical Engineering, Dalian University of Technology 2 Linggong Road 116024 Dalian China
| | - Li Yang
- Department of Pharmaceutical Science, School of Chemical Engineering, Dalian University of Technology 2 Linggong Road 116024 Dalian China
| | - Jiawei Xu
- College of Pharmacy, Liaoning University of Traditional Medicine 110847 Shenyang China
| | - Engin U Akkaya
- State Key Laboratory of Fine Chemicals, Dalian University of Technology 2 Linggong Road 116024 Dalian China .,Department of Pharmaceutical Science, School of Chemical Engineering, Dalian University of Technology 2 Linggong Road 116024 Dalian China
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7
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Yan J, Wang C, Jiang X, Wei Y, Wang Q, Cui K, Xu X, Wang F, Zhang L. Application of phototherapeutic-based nanoparticles in colorectal cancer. Int J Biol Sci 2021; 17:1361-1381. [PMID: 33867852 PMCID: PMC8040477 DOI: 10.7150/ijbs.58773] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 03/12/2021] [Indexed: 02/06/2023] Open
Abstract
Colorectal cancer (CRC) is the third most commonly diagnosed malignancy and the second leading cause of cancer death, which accounts for approximately 10% of all new cancer cases worldwide. Surgery is the main method for treatment of early-stage CRC. However, it is not effective for most metastatic tumors, and new treatment and diagnosis strategies need to be developed. Photosensitizers (PSs) play an important role in the treatment of CRC. Phototherapy also has a broad prospect in the treatment of CRC because of its low invasiveness and low toxicity. However, most PSs are associated with limitations including poor solubility, poor selectivity and high toxicity. The application of nanomaterials in PSs has added many advantages, including increased solubility, bioavailability, targeting, stability and low toxicity. In this review, based on phototherapy, we discuss the characteristics and development progress of PSs, the targeting of PSs at organ, cell and molecular levels, and the current methods of optimizing PSs, especially the application of nanoparticles as carriers in CRC. We introduce the photosensitizer (PS) targeting process in photodynamic therapy (PDT), the damage mechanism of PDT, and the application of classic PS in CRC. The action process and damage mechanism of photothermal therapy (PTT) and the types of ablation agents. In addition, we present the imaging examination and the application of PDT / PTT in tumor, including (fluorescence imaging, photoacoustic imaging, nuclear magnetic resonance imaging, nuclear imaging) to provide the basis for the early diagnosis of CRC. Notably, single phototherapy has several limitations in vivo, especially for deep tumors. Here, we discuss the advantages of the combination therapy of PDT and PTT compared with the single therapy. At the same time, this review summarizes the clinical application of PS in CRC. Although a variety of nanomaterials are in the research and development stage, few of them are actually on the market, they will show great advantages in the treatment of CRC in the near future.
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Affiliation(s)
- Jiaxin Yan
- Bioinformatics Center, School of Basic Medical Sciences, Henan University, Kaifeng 475004, China.,School of Pharmacy, Henan University, Kaifeng Kaifeng 475004, China
| | - Chunli Wang
- Bioinformatics Center, School of Basic Medical Sciences, Henan University, Kaifeng 475004, China.,School of Basic Medical Sciences, Henan University, Kaifeng 475004, China
| | - Xiaomei Jiang
- School of Basic Medical Sciences, Henan University, Kaifeng 475004, China
| | - Yiqu Wei
- School of Basic Medical Sciences, Henan University, Kaifeng 475004, China
| | - Qun Wang
- School of Basic Medical Sciences, Henan University, Kaifeng 475004, China
| | - Kunli Cui
- School of Basic Medical Sciences, Henan University, Kaifeng 475004, China
| | - Xiao Xu
- School of Basic Medical Sciences, Henan University, Kaifeng 475004, China
| | - Feng Wang
- Guangming Substation of Shenzhen Ecological Environment Monitoring Station, Shenzhen 518107, P. R. China
| | - Lei Zhang
- School of Basic Medical Sciences, Henan University, Kaifeng 475004, China
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8
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Shah N, Zhou L. Regulation of Ion Channel Function by Gas Molecules. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1349:139-164. [DOI: 10.1007/978-981-16-4254-8_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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9
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Makhneva ZK, Ashikhmin AA, Bolshakov MA, Moskalenko AA. Carotenoids are Probably Involved in Singlet Oxygen Generation in the Membranes of Purple Photosynthetic Bacteria under Light Irradiation. Microbiology (Reading) 2020. [DOI: 10.1134/s0026261720010099] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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10
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Prasad A, Sedlářová M, Balukova A, Rác M, Pospíšil P. Reactive Oxygen Species as a Response to Wounding: In Vivo Imaging in Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2020; 10:1660. [PMID: 31998345 PMCID: PMC6962234 DOI: 10.3389/fpls.2019.01660] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Accepted: 11/25/2019] [Indexed: 05/29/2023]
Abstract
Mechanical injury or wounding in plants can be attributed to abiotic or/and biotic causes. Subsequent defense responses are either local, i.e. within or in the close vicinity of affected tissue, or systemic, i.e. at distant plant organs. Stress stimuli activate a plethora of early and late reactions, from electric signals induced within seconds upon injury, oxidative burst within minutes, and slightly slower changes in hormone levels or expression of defense-related genes, to later cell wall reinforcement by polysaccharides deposition, or accumulation of proteinase inhibitors and hydrolytic enzymes. In the current study, we focused on the production of reactive oxygen species (ROS) in wounded Arabidopsis leaves. Based on fluorescence imaging, we provide experimental evidence that ROS [superoxide anion radical (O2 •-) and singlet oxygen (1O2)] are produced following wounding. As a consequence, oxidation of biomolecules is induced, predominantly of polyunsaturated fatty acid, which leads to the formation of reactive intermediate products and electronically excited species.
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Affiliation(s)
- Ankush Prasad
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Olomouc, Czechia
| | - Michaela Sedlářová
- Department of Botany, Faculty of Science, Palacký University, Olomouc, Czechia
| | - Anastasiia Balukova
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Olomouc, Czechia
| | - Marek Rác
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Olomouc, Czechia
| | - Pavel Pospíšil
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Olomouc, Czechia
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11
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Abstract
This year marks the 50th anniversary of the discovery of σ70 as a protein factor that was needed for bacterial RNA polymerase to accurately transcribe a promoter in vitro. It was 25 years later that the Group IV alternative σs were described as a distinct family of proteins related to σ70 . In the intervening time, there has been an ever-growing list of Group IV σs, numbers of genes they transcribe, insight into the diverse suite of processes they control, and appreciation for their impact on bacterial lifestyles. This work summarizes knowledge of the Rhodobacter sphaeroides σE -ChrR pair, a member of the ECF11 subfamily of Group IV alternative σs, in protecting cells from the reactive oxygen species, singlet oxygen. It describes lessons learned from analyzing ChrR, a zinc-dependent anti-σ factor, that are generally applicable to Group IV σs and relevant to the response to single oxygen. This MicroReview also illustrates insights into stress responses in this and other bacteria that have been acquired by analyzing or modeling the activity of the σE -ChrR across the bacterial phylogeny.
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Affiliation(s)
- Timothy J. Donohue
- Bacteriology Department, Great Lakes Bioenergy Research CenterWisconsin Energy Institute, University of Wisconsin‐MadisonMadisonWI53726USA
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12
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Makhneva ZK, Ashikhmin AA, Bolshakov MA, Moskalenko AA. Quenchers Protect BChl850 from Action of Singlet Oxygen in the Membranes of a Sulfur Photosynthetic Bacterium Allochromatium vinosum Strain MSU. Microbiology (Reading) 2019. [DOI: 10.1134/s0026261719010119] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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13
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Abstract
The concept of cell signaling in the context of nonenzyme-assisted protein modifications by reactive electrophilic and oxidative species, broadly known as redox signaling, is a uniquely complex topic that has been approached from numerous different and multidisciplinary angles. Our Review reflects on five aspects critical for understanding how nature harnesses these noncanonical post-translational modifications to coordinate distinct cellular activities: (1) specific players and their generation, (2) physicochemical properties, (3) mechanisms of action, (4) methods of interrogation, and (5) functional roles in health and disease. Emphasis is primarily placed on the latest progress in the field, but several aspects of classical work likely forgotten/lost are also recollected. For researchers with interests in getting into the field, our Review is anticipated to function as a primer. For the expert, we aim to stimulate thought and discussion about fundamentals of redox signaling mechanisms and nuances of specificity/selectivity and timing in this sophisticated yet fascinating arena at the crossroads of chemistry and biology.
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Affiliation(s)
- Saba Parvez
- Department of Pharmacology and Toxicology, College of
Pharmacy, University of Utah, Salt Lake City, Utah, 84112, USA
- Department of Chemistry and Chemical Biology, Cornell
University, Ithaca, New York, 14853, USA
| | - Marcus J. C. Long
- Department of Chemistry and Chemical Biology, Cornell
University, Ithaca, New York, 14853, USA
| | - Jesse R. Poganik
- Ecole Polytechnique Fédérale de Lausanne,
Institute of Chemical Sciences and Engineering, 1015, Lausanne, Switzerland
- Department of Chemistry and Chemical Biology, Cornell
University, Ithaca, New York, 14853, USA
| | - Yimon Aye
- Ecole Polytechnique Fédérale de Lausanne,
Institute of Chemical Sciences and Engineering, 1015, Lausanne, Switzerland
- Department of Chemistry and Chemical Biology, Cornell
University, Ithaca, New York, 14853, USA
- Department of Biochemistry, Weill Cornell Medicine, New
York, New York, 10065, USA
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14
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Idikuda V, Gao W, Grant K, Su Z, Liu Q, Zhou L. Singlet oxygen modification abolishes voltage-dependent inactivation of the sea urchin spHCN channel. J Gen Physiol 2018; 150:1273-1286. [PMID: 30042141 PMCID: PMC6122923 DOI: 10.1085/jgp.201711961] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 04/27/2018] [Accepted: 06/15/2018] [Indexed: 11/20/2022] Open
Abstract
Photochemically or metabolically generated singlet oxygen (1O2) reacts broadly with macromolecules in the cell. Because of its short lifetime and working distance, 1O2 holds potential as an effective and precise nanoscale tool for basic research and clinical practice. Here we investigate the modification of the spHCN channel that results from photochemically and chemically generated 1O2 The spHCN channel shows strong voltage-dependent inactivation in the absence of cAMP. In the presence of photosensitizers, short laser pulses transform the gating properties of spHCN by abolishing inactivation and increasing the macroscopic current amplitude. Alanine replacement of a histidine residue near the activation gate within the channel's pore abolishes key modification effects. Application of a variety of chemicals including 1O2 scavengers and 1O2 generators supports the involvement of 1O2 and excludes other reactive oxygen species. This study provides new understanding about the photodynamic modification of ion channels by 1O2 at the molecular level.
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Affiliation(s)
- Vinay Idikuda
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, Richmond, VA
| | - Weihua Gao
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, Richmond, VA
| | - Khade Grant
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, Richmond, VA
| | - Zhuocheng Su
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, Richmond, VA
| | - Qinglian Liu
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, Richmond, VA
| | - Lei Zhou
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, Richmond, VA
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15
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Abstract
Photodynamic therapy (PDT) involves the combination of non-toxic dyes called photosensitizers (PS) and harmless visible light that interact with ambient oxygen to give reactive oxygen species (ROS) that can damage biomolecules and kill cells. PDT has mostly been developed as a cancer therapy but can also be used as an antimicrobial approach against localized infections. However even the longest wavelength used for exciting PS (in the 700 nm region) has relatively poor tissue penetration, and many PS are much better excited by blue and green light. Therefore upconversion nanoparticles (UCNPs) have been investigated in order to allow deeper-penetrating near-infrared light (980 nm or 810 nm) to be used for PDT. NaYF4 nanoparticles doped with Yb3+ and Er3+ or with Tm3+ and Er3+ have been attached to PS either by covalent conjugation, or by absorption to the coating or shell (used to render the UCNPs biocompatible). Forster resonance energy transfer to the PS then allows NIR light energy to be transduced into ROS leading to cell killing and tumor regression. Some studies have experimentally demonstrated the deep tissue advantage of UCNP-PDT. Recent advances have included dye-sensitized UCNPs and UCNPs coupled to PS, and other potentially synergistic drug molecules or techniques. A variety of bioimaging modalities have also been combined with upconversion PDT. Further studies are necessary to optimize the drug-delivery abilities of the UCNPs, improve the quantum yields, allow intravenous injection and tumor targeting, and ensure lack of toxicity at the required doses before potential clinical applications.
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Affiliation(s)
- Michael R Hamblin
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA, 02114 USA
- Department of Dermatology, Harvard Medical School, Boston, MA 02115, USA
- Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA 02139, USA
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16
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17
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Morris G, Puri BK, Frye RE. The putative role of environmental aluminium in the development of chronic neuropathology in adults and children. How strong is the evidence and what could be the mechanisms involved? Metab Brain Dis 2017; 32:1335-1355. [PMID: 28752219 PMCID: PMC5596046 DOI: 10.1007/s11011-017-0077-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Accepted: 07/19/2017] [Indexed: 02/06/2023]
Abstract
The conceptualisation of autistic spectrum disorder and Alzheimer's disease has undergone something of a paradigm shift in recent years and rather than being viewed as single illnesses with a unitary pathogenesis and pathophysiology they are increasingly considered to be heterogeneous syndromes with a complex multifactorial aetiopathogenesis, involving a highly complex and diverse combination of genetic, epigenetic and environmental factors. One such environmental factor implicated as a potential cause in both syndromes is aluminium, as an element or as part of a salt, received, for example, in oral form or as an adjuvant. Such administration has the potential to induce pathology via several routes such as provoking dysfunction and/or activation of glial cells which play an indispensable role in the regulation of central nervous system homeostasis and neurodevelopment. Other routes include the generation of oxidative stress, depletion of reduced glutathione, direct and indirect reductions in mitochondrial performance and integrity, and increasing the production of proinflammatory cytokines in both the brain and peripherally. The mechanisms whereby environmental aluminium could contribute to the development of the highly specific pattern of neuropathology seen in Alzheimer's disease are described. Also detailed are several mechanisms whereby significant quantities of aluminium introduced via immunisation could produce chronic neuropathology in genetically susceptible children. Accordingly, it is recommended that the use of aluminium salts in immunisations should be discontinued and that adults should take steps to minimise their exposure to environmental aluminium.
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Affiliation(s)
- Gerwyn Morris
- Tir Na Nog, Bryn Road seaside 87, Llanelli, Wales, SA15 2LW, UK
| | - Basant K Puri
- Department of Medicine, Imperial College London, Hammersmith Hospital, London, England, W12 0HS, UK.
| | - Richard E Frye
- College of Medicine, Department of Pediatrics, University of Arkansas for Medical Sciences, Arkansas Children's Hospital Research Institute, Little Rock, AR, 72202, USA
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18
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Prasad A, Sedlářová M, Kale RS, Pospíšil P. Lipoxygenase in singlet oxygen generation as a response to wounding: in vivo imaging in Arabidopsis thaliana. Sci Rep 2017; 7:9831. [PMID: 28851974 PMCID: PMC5575249 DOI: 10.1038/s41598-017-09758-1] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Accepted: 07/28/2017] [Indexed: 11/09/2022] Open
Abstract
Wounding, one of the most intensive stresses influencing plants ontogeny and lifespan, can be induced by herbivory as well as by physical factors. Reactive oxygen species play indispensable role both in the local and systemic defense reactions which enable "reprogramming" of metabolic pathways to set new boundaries and physiological equilibrium suitable for survival. In our current study, we provide experimental evidence on the formation of singlet oxygen (1O2) after wounding of Arabidopsis leaves. It is shown that 1O2 is formed by triplet-triplet energy transfer from triplet carbonyls to molecular oxygen. Using lipoxygenase inhibitor catechol, it is demonstrated that lipid peroxidation is initiated by lipoxygenase. Suppression of 1O2 formation in lox2 mutant which lacks chloroplast lipoxygenase indicates that lipoxygenase localized in chloroplast is predominantly responsible for 1O2 formation. Interestingly, 1O2 formation is solely restricted to chloroplasts localized at the wounding site. Data presented in this study might provide novel insight into wound-induced signaling in the local defense reaction.
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Affiliation(s)
- Ankush Prasad
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71, Olomouc, Czech Republic
| | - Michaela Sedlářová
- Department of Botany, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71, Olomouc, Czech Republic
| | - Ravindra Sonajirao Kale
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71, Olomouc, Czech Republic
| | - Pavel Pospíšil
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71, Olomouc, Czech Republic.
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19
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Regulation and function of tetrapyrrole biosynthesis in plants and algae. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1847:968-85. [PMID: 25979235 DOI: 10.1016/j.bbabio.2015.05.007] [Citation(s) in RCA: 127] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 04/21/2015] [Accepted: 05/07/2015] [Indexed: 12/20/2022]
Abstract
Tetrapyrroles are macrocyclic molecules with various structural variants and multiple functions in Prokaryotes and Eukaryotes. Present knowledge about the metabolism of tetrapyrroles reflects the complex evolution of the pathway in different kingdoms of organisms, the complexity of structural and enzymatic variations of enzymatic steps, as well as a wide range of regulatory mechanisms, which ensure adequate synthesis of tetrapyrrole end-products at any time of development and environmental condition. This review intends to highlight new findings of research on tetrapyrrole biosynthesis in plants and algae. In the course of the heme and chlorophyll synthesis in these photosynthetic organisms, glutamate, one of the central and abundant metabolites, is converted into highly photoreactive tetrapyrrole intermediates. Thereby, several mechanisms of posttranslational control are thought to be essential for a tight regulation of each enzymatic step. Finally, we wish to discuss the potential role of tetrapyrroles in retrograde signaling and point out perspectives of the formation of macromolecular protein complexes in tetrapyrrole biosynthesis as an efficient mechanism to ensure a fine-tuned metabolic flow in the pathway. This article is part of a Special Issue entitled: Chloroplast Biogenesis.
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Weber G, Charitat T, Baptista MS, Uchoa AF, Pavani C, Junqueira HC, Guo Y, Baulin VA, Itri R, Marques CM, Schroder AP. Lipid oxidation induces structural changes in biomimetic membranes. SOFT MATTER 2014; 10:4241-7. [PMID: 24871383 DOI: 10.1039/c3sm52740a] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Oxidation can intimately influence and structurally compromise the levels of biological self-assembly embodied by intracellular and plasma membranes. Lipid peroxidation, a natural metabolic outcome of life with oxygen under light, is also a salient oxidation reaction in photomedicine treatments. However, the effect of peroxidation on the fate of lipid membranes remains elusive. Here we use a new photosensitizer that anchors and disperses in the membrane to achieve spatial control of the oxidizing species. We find, surprisingly, that the integrity of unsaturated unilamellar vesicles is preserved even for fully oxidized membranes. Membrane survival allows for the quantification of the transformations of the peroxidized bilayers, providing key physical and chemical information to understand the effect of lipid oxidation on protein insertion and on other mechanisms of cell function. We anticipate that spatially controlled oxidation will emerge as a new powerful strategy for tuning and evaluating lipid membranes in biomimetic media under oxidative stress.
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Affiliation(s)
- Georges Weber
- Present address: FOM Institute AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
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21
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Gao W, Su Z, Liu Q, Zhou L. State-dependent and site-directed photodynamic transformation of HCN2 channel by singlet oxygen. ACTA ACUST UNITED AC 2014; 143:633-44. [PMID: 24733837 PMCID: PMC4003188 DOI: 10.1085/jgp.201311112] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Singlet oxygen acts through a histidine residue to delay HCN channel deactivation and enhance voltage-insensitive current. Singlet oxygen (1O2), which is generated through metabolic reactions and oxidizes numerous biological molecules, has been a useful tool in basic research and clinical practice. However, its role as a signaling factor, as well as a mechanistic understanding of the oxidation process, remains poorly understood. Here, we show that hyperpolarization-activated, cAMP-gated (HCN) channels–which conduct the hyperpolarization-activated current (Ih) and the voltage-insensitive instantaneous current (Iinst), and contribute to diverse physiological functions including learning and memory, cardiac pacemaking, and the sensation of pain–are subject to modification by 1O2. To increase the site specificity of 1O2 generation, we used fluorescein-conjugated cAMP, which specifically binds to HCN channels, or a chimeric channel in which an in-frame 1O2 generator (SOG) protein was fused to the HCN C terminus. Millisecond laser pulses reduced Ih current amplitude, slowed channel deactivation, and enhanced Iinst current. The modification of HCN channel function is a photodynamic process that involves 1O2, as supported by the dependence on dissolved oxygen in solutions, the inhibitory effect by a 1O2 scavenger, and the results with the HCN2-SOG fusion protein. Intriguingly, 1O2 modification of the HCN2 channel is state dependent: laser pulses applied to open channels mainly slow down deactivation and increase Iinst, whereas for the closed channels, 1O2 modification mainly reduced Ih amplitude. We identified a histidine residue (H434 in S6) near the activation gate in the pore critical for 1O2 modulation of HCN function. Alanine replacement of H434 abolished the delay in channel deactivation and the generation of Iinst induced by photodynamic modification. Our study provides new insights into the instantaneous current conducted by HCN channels, showing that modifications to the region close to the intracellular gate underlie the expression of Iinst, and establishes a well-defined model for studying 1O2 modifications at the molecular level.
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Affiliation(s)
- Weihua Gao
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, Richmond, VA 23298
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Kiesslich T, Tortik N, Pichler M, Neureiter D, Plaetzer K. Apoptosis in cancer cells induced by photodynamic treatment – a methodological approach. J PORPHYR PHTHALOCYA 2013. [DOI: 10.1142/s1088424613300036] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Photodynamic therapy (PDT) is approved for clinical indications including several (pre-) cancers of the skin and solid tumors of the brain and the gastrointestinal tract. It operates by an acute cellular response caused by oxidation of cell components following light-induced and photosensitizer-mediated generation of reactive oxygen species. By this, PDT is capable of inducing the major types of cytotoxic responses: autophagy, apoptosis, and necrosis. As excited photosensitizer molecules react rather non-specifically with neighboring molecules, we suggest that with PDT and most (if not any) cell-localizing photosensitizers, all kinds of cellular responses can be provoked — following a strict dose-dependency, i.e. a transition from survival, over apoptosis to necrosis depending on the applied photosensitizer concentration or light dose. In this review, we briefly discuss (i) the types of cell death induced by PDT focusing on apoptosis induction, (ii) a simple experimental approach to quickly assess the dose-dependent phototoxic responses based on viability assays, and (iii) an overview of in vitro apoptosis detection methods for further in depth analyses. With this conceptual framework, we attempt to provide a rational experimental approach for initial in vitro, cell-based characterization of newly synthesized photosensitizers or formulations thereof — thus to plug the gap between subsequent in vivo evaluation and the preceding fundamental (physico-)chemical work devoted to the improvement of photosensitizing drugs based on mainly porphyrins, phthalocyanines and their derivatives.
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Affiliation(s)
- Tobias Kiesslich
- Department of Internal Medicine I, Paracelsus Medical University/Salzburger Landeskliniken (SALK), Muellner Haupstrasse 48, 5020 Salzburg, Austria
- Institute of Physiology and Pathophysiology, Paracelsus Medical University, Strubergasse 21, 5020 Salzburg, Austria
| | - Nicole Tortik
- Laboratory of Photodynamic Inactivation of Microorganisms (PDI-PLUS), Division of Physics and Biophysics, University of Salzburg, Hellbrunnerstrasse 34, 5020 Salzburg, Austria
| | - Martin Pichler
- Division of Oncology, Department of Internal Medicine, Medical University of Graz (MUG), Auenbruggerplatz 15, 8036 Graz, Austria
| | - Daniel Neureiter
- Institute of Pathology, Paracelsus Medical University/Salzburger Landeskliniken (SALK), Muellner Haupstrasse 48, 5020 Salzburg, Austria
| | - Kristjan Plaetzer
- Laboratory of Photodynamic Inactivation of Microorganisms (PDI-PLUS), Division of Physics and Biophysics, University of Salzburg, Hellbrunnerstrasse 34, 5020 Salzburg, Austria
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Bolisetty S, Jaimes EA. Mitochondria and reactive oxygen species: physiology and pathophysiology. Int J Mol Sci 2013; 14:6306-44. [PMID: 23528859 PMCID: PMC3634422 DOI: 10.3390/ijms14036306] [Citation(s) in RCA: 176] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Revised: 03/08/2013] [Accepted: 03/11/2013] [Indexed: 02/06/2023] Open
Abstract
The air that we breathe contains nearly 21% oxygen, most of which is utilized by mitochondria during respiration. While we cannot live without it, it was perceived as a bane to aerobic organisms due to the generation of reactive oxygen and nitrogen metabolites by mitochondria and other cellular compartments. However, this dogma was challenged when these species were demonstrated to modulate cellular responses through altering signaling pathways. In fact, since this discovery of a dichotomous role of reactive species in immune function and signal transduction, research in this field grew at an exponential pace and the pursuit for mechanisms involved began. Due to a significant number of review articles present on the reactive species mediated cell death, we have focused on emerging novel pathways such as autophagy, signaling and maintenance of the mitochondrial network. Despite its role in several processes, increased reactive species generation has been associated with the origin and pathogenesis of a plethora of diseases. While it is tempting to speculate that anti-oxidant therapy would protect against these disorders, growing evidence suggests that this may not be true. This further supports our belief that these reactive species play a fundamental role in maintenance of cellular and tissue homeostasis.
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Affiliation(s)
- Subhashini Bolisetty
- Nephrology Division, University of Alabama at Birmingham, Birmingham, AL 35294, USA; E-Mail:
| | - Edgar A. Jaimes
- Nephrology Division, University of Alabama at Birmingham, Birmingham, AL 35294, USA; E-Mail:
- Veterans Affairs Medical Center, Birmingham, AL 35233, USA
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Ivanov S, Shopova E, Kerchev P, Sergiev I, Miteva L, Polizoev D, Alexieva V. Long-term impact of sublethal atrazine perturbs the redox homeostasis in pea (Pisum sativum L.) plants. PROTOPLASMA 2013; 250:95-102. [PMID: 22367533 DOI: 10.1007/s00709-012-0378-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2011] [Accepted: 01/13/2012] [Indexed: 05/13/2023]
Abstract
Atrazine frequently contaminates soil, groundwater, rivers, and ponds. It is well know that acute doses (1-5 mM) of atrazine induce massive generation of singlet oxygen by blocking photosystem II. The sublethal concentrations of this herbicide, similar to those found in the environment, also reduce growth and disrupt photosynthesis in a long-term aspect, but exact mechanisms remain much uncertain. In this study the effects of environmentally relevant atrazine levels, ranging from 0.1 to 10 μM, on pea plants were characterized for up to 20 days. The plants exposed to continuous influence of atrazine exhibited perturbed redox homeostasis with increases of the lipid peroxides, the total and oxidized glutathione pools and elevated guaiacol peroxidase and glutathione-S-transferase activities. In contrast, the long-term atrazine impact did not affect superoxide dismutase activity whereas the catalase was inhibited. The perturbations of the redox status and the recruitment of the antioxidant machinery imply that the sublethal atrazine concentrations alter the poise between production and scavenging of reactive oxygen species. Taken together these results show that the long-term impact of sublethal atrazine has hallmarks of oxidative stress most probably triggered by generation of singlet oxygen.
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Affiliation(s)
- Sergei Ivanov
- Centre of Food Biology, PO Box 120, Sofia 1592, Bulgaria.
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25
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Sperandio FF, Sharma SK, Wang M, Jeon S, Huang YY, Dai T, Nayka S, de Sousa SCOM, Chiang LY, Hamblin MR. Photoinduced electron-transfer mechanisms for radical-enhanced photodynamic therapy mediated by water-soluble decacationic C₇₀ and C₈₄O₂ Fullerene Derivatives. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2012; 9:570-9. [PMID: 23117043 DOI: 10.1016/j.nano.2012.09.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2012] [Revised: 09/19/2012] [Accepted: 09/29/2012] [Indexed: 02/03/2023]
Abstract
UNLABELLED Fullerenes are promising candidates for photodynamic therapy (PDT). Thus, C₇₀ and novel C₈₄O₂ fullerenes were functionalized with and without an additional deca-tertiary ethyleneamino-chain as an electron source, giving rise to two distinct pairs of photosensitizers, the monoadducts LC-17, LC-19 and the bisadducts LC18 and LC-20 to perform PDT in HeLa cells with UVA, blue, green, white and red light. Shorter wavelengths gave more phototoxicity with LC-20 while LC-19 was better at longer wavelengths; the ratio between killing obtained with LC-19 and LC-20 showed an almost perfect linear correlation (R = 0.975) with wavelength. The incorporation of a deca-tertiary amine chain in the C₈₄O₂ fullerene gave more PDT killing when excited with shorter wavelengths or in the presence of low ascorbate concentration through higher generation of hydroxyl radicals. Photoactivated C₈₄O₂ fullerenes induced apoptosis of HeLa cancer cells, together with mitochondrial and lysosomal damage demonstrated by acridine orange and rhodamine 123 fluorescent probes. FROM THE CLINICAL EDITOR Photoactivated C₇₀ and C₈₄O₂ fullerenes were demonstrated to induce apoptosis of HeLa cancer cells, together with mitochondrial and lysosomal damage, as a function of wavelength. The study is paving the way to future clinical uses of these agents in photodynamic therapy.
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Affiliation(s)
- Felipe F Sperandio
- Department of Oral Pathology, School of Dentistry, University of Sao Paulo, Sao Paulo, SP 05508-000, Brazil
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SINGLET OXYGEN RESISTANT 1 links reactive electrophile signaling to singlet oxygen acclimation in Chlamydomonas reinhardtii. Proc Natl Acad Sci U S A 2012; 109:E1302-11. [PMID: 22529359 DOI: 10.1073/pnas.1116843109] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Acclimation of Chlamydomonas reinhardtii cells to low levels of singlet oxygen, produced either by photoreactive chemicals or high light treatment, induces a specific genetic response that strongly increases the tolerance of the algae to subsequent exposure to normally lethal singlet oxygen-producing conditions. The genetic response includes the increased expression of various oxidative stress response and detoxification genes, like the glutathione peroxidase homologous gene GPXH/GPX5 and the σ-class glutathione-S-transferase gene GSTS1. To identify components involved in the signal transduction and activation of the singlet oxygen-mediated response, a mutant selection was performed. This selection led to the isolation of the singlet oxygen resistant 1 (sor1) mutant, which is more tolerant to singlet oxygen-producing chemicals and shows a constitutively higher expression of GPXH and GSTS1. Map-based cloning revealed that the SOR1 gene encodes a basic leucine zipper transcription factor, which controls its own expression and the expression of a large number of oxidative stress response and detoxification genes. In the promoter region of many of these genes, a highly conserved 8-bp palindromic sequence element was found to be enriched. This element was essential for GSTS1 induction by increased levels of lipophilic reactive electrophile species (RES), suggesting that it functions as an electrophile response element (ERE). Furthermore, GSTS1 overexpression in sor1 requires the ERE, although it is unknown whether it occurs through direct binding of SOR1 to the ERE. RES can be formed after singlet oxygen-induced lipid peroxidation, indicating that RES-stimulated and SOR1-mediated responses of detoxification genes are part of the singlet oxygen-induced acclimation process in C. reinhardtii.
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Greenwell R, Nam TW, Donohue TJ. Features of Rhodobacter sphaeroides ChrR required for stimuli to promote the dissociation of σ(E)/ChrR complexes. J Mol Biol 2011; 407:477-91. [PMID: 21295582 DOI: 10.1016/j.jmb.2011.01.055] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2010] [Revised: 01/14/2011] [Accepted: 01/28/2011] [Indexed: 10/18/2022]
Abstract
In the photosynthetic bacterium Rhodobacter sphaeroides, a transcriptional response to the reactive oxygen species singlet oxygen ((1)O(2)) is mediated by ChrR, a zinc metalloprotein that binds to and inhibits the activity of the alternative σ factor σ(E). We provide evidence that (1)O(2) promotes the dissociation of σ(E) from ChrR to activate transcription in vivo. To identify what is required for (1)O(2) to promote the dissociation of σ(E)/ChrR complexes, we analyzed the in vivo properties of variant ChrR proteins with amino acid changes in conserved residues of the C-terminal cupin-like domain (ChrR-CLD). We found that (1)O(2) was unable to promote the detectable dissociation of σ(E)/ChrR complexes when the ChrR-CLD zinc ligands (His141, His143, Glu147, and His177) were substituted with alanine, even though individual substitutions caused a 2-fold to 10-fold decrease in zinc affinity for this domain relative to that for wild-type ChrR (K(d)∼4.6×10(-)(10) M). We conclude that the side chains of these invariant residues play a crucial role in the response to (1)O(2). Additionally, we found that cells containing variant ChrR proteins with single amino acid substitutions at Cys187 or Cys189 exhibited σ(E) activity similar to those containing wild-type ChrR when exposed to (1)O(2), suggesting that these thiol side chains are not required for (1)O(2) to induce σ(E) activity in vivo. Finally, we found that the same aspects of R. sphaeroides ChrR needed for a response to (1)O(2) are required for the dissociation of σ(E)/ChrR complexes in the presence of the organic hydroperoxide t-butyl hydroperoxide.
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Affiliation(s)
- Roger Greenwell
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA
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28
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Abstract
The cornified cell envelope (CE) is a specialized structure assembled beneath the plasma membrane of keratinocytes in the outermost layers of the epidermis. It is essential for the physical and permeability properties of the barrier function of the skin. Our skin is continuously exposed to atmospheric oxygen and threatened by reactive oxygen species (ROS). Here, we identify the CE as a first line of antioxidant defense and show that the small proline-rich (SPRR) family of CE precursor proteins have a major role in ROS detoxification. Cysteine residues within these proteins are responsible for ROS quenching, resulting in inter- and intramolecular S-S bond formation, both in isolated proteins and purified CEs. The related keratinocyte proline-rich protein is also oxidized on several cysteine residues within the CE. Differences in antioxidant potential between various SPRR family members are likely determined by structural differences rather than by the amount of cysteine residues per protein. Loricrin, a major component of the CE with a higher cysteine content than SPRRs, is a weak ROS quencher and oxidized on a single cysteine residue within the CE. It is inferred that SPRR proteins provide the outermost layer of our skin with a highly adaptive and protective antioxidant shield.
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Vermeij WP, Backendorf C. Skin cornification proteins provide global link between ROS detoxification and cell migration during wound healing. PLoS One 2010; 5:e11957. [PMID: 20689819 PMCID: PMC2914756 DOI: 10.1371/journal.pone.0011957] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2010] [Accepted: 07/11/2010] [Indexed: 12/25/2022] Open
Abstract
Wound healing is a complex dynamic process characterised by a uniform flow of events in nearly all types of tissue damage, from a small skin scratch to myocardial infarction. Reactive oxygen species (ROS) are essential during the healing process at multiple stages, ranging from the initial signal that instigates the immune response, to the triggering of intracellular redox-dependent signalling pathways and the defence against invading bacteria. Excessive ROS in the wound milieu nevertheless impedes new tissue formation. Here we identify small proline-rich (SPRR) proteins as essential players in this latter process, as they directly link ROS detoxification with cell migration. A literature-based meta-analysis revealed their up-regulation in various forms of tissue injury, ranging from heart infarction and commensal-induced gut responses to nerve regeneration and burn injury. Apparently, SPRR proteins have a far more widespread role in wound healing and tissue remodelling than their established function in skin cornification. It is inferred that SPRR proteins provide injured tissue with an efficient, finely tuneable antioxidant barrier specifically adapted to the tissue involved and the damage inflicted. Their recognition as novel cell protective proteins combining ROS detoxification with cell migration will provide new venues to study and manage tissue repair and wound healing at a molecular level.
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Affiliation(s)
- Wilbert P. Vermeij
- Laboratory of Molecular Genetics, Faculty of Science, Leiden University, Leiden, The Netherlands
| | - Claude Backendorf
- Laboratory of Molecular Genetics, Faculty of Science, Leiden University, Leiden, The Netherlands
- * E-mail:
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Singlet oxygen-dependent translational control in the tigrina-d.12 mutant of barley. Proc Natl Acad Sci U S A 2009; 106:13112-7. [PMID: 19620736 DOI: 10.1073/pnas.0903522106] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The tigrina (tig)-d.12 mutant of barley is impaired in the negative control limiting excess protochlorophyllide (Pchlide) accumulation in the dark. Upon illumination, Pchlide operates as photosensitizer and triggers singlet oxygen production and cell death. Here, we show that both Pchlide and singlet oxygen operate as signals that control gene expression and metabolite accumulation in tig-d.12 plants. In vivo labeling, Northern blotting, polysome profiling, and protein gel blot analyses revealed a selective suppression of synthesis of the small and large subunits of ribulose-1,5-bisphosphate carboxylase/oxygenase (RBCSs and RBCLs), the major light-harvesting chlorophyll a/b-binding protein of photosystem II (LHCB2), as well as other chlorophyll-binding proteins, in response to singlet oxygen. In part, these effects were caused by an arrest in translation initiation of photosynthetic transcripts at 80S cytoplasmic ribosomes. The observed changes in translation correlated with a decline in the phosphorylation level of ribosomal protein S6. At later stages, ribosome dissociation occurred. Together, our results identify translation as a major target of singlet oxygen-dependent growth control and cell death in higher plants.
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31
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Kleine T, Voigt C, Leister D. Plastid signalling to the nucleus: messengers still lost in the mists? Trends Genet 2009; 25:185-92. [PMID: 19303165 DOI: 10.1016/j.tig.2009.02.004] [Citation(s) in RCA: 141] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2009] [Revised: 02/17/2009] [Accepted: 02/17/2009] [Indexed: 02/05/2023]
Abstract
The concept of plastid signalling posits that signals originating from chloroplasts modulate nuclear gene expression (NGE). Put simply, it claims that signalling factors are exported from the chloroplast, traverse the cytosol, and act in the nucleus. Pertinent signals are thought to derive from various sources, including the tetrapyrrole pathway, protein synthesis, reactive oxygen species, or the redox state of the organelle. Recent studies have cast doubt on the most popular candidate signalling molecule, the tetrapyrrole pathway intermediate Mg-protoporphyrin IX, indicating that chloroplast activity might control NGE indirectly by affecting cytosolic metabolite levels or redox states (metabolic signalling). Here, we focus on recent developments and confusions in the field of plastid signalling research and highlight alternative scenarios of plastid-nucleus signal transduction. Future analyses of chloroplast-nucleus communication should focus on providing an integrated view of plastid signalling under physiologically relevant conditions.
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Affiliation(s)
- Tatjana Kleine
- Department of Biology, Ludwig-Maximilians-University Munich, Grosshaderner Strasse 2, D-82152 Planegg-Martinsried, Germany
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Juzenas P, Chen W, Sun YP, Coelho MAN, Generalov R, Generalova N, Christensen IL. Quantum dots and nanoparticles for photodynamic and radiation therapies of cancer. Adv Drug Deliv Rev 2008; 60:1600-14. [PMID: 18840487 PMCID: PMC2695009 DOI: 10.1016/j.addr.2008.08.004] [Citation(s) in RCA: 343] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2008] [Accepted: 08/16/2008] [Indexed: 12/18/2022]
Abstract
Semiconductor quantum dots and nanoparticles composed of metals, lipids or polymers have emerged with promising applications for early detection and therapy of cancer. Quantum dots with unique optical properties are commonly composed of cadmium contained semiconductors. Cadmium is potentially hazardous, and toxicity of such quantum dots to living cells, and humans, is not yet systematically investigated. Therefore, search for less toxic materials with similar targeting and optical properties is of further interest. Whereas, the investigation of luminescence nanoparticles as light sources for cancer therapy is very interesting. Despite advances in neurosurgery and radiotherapy the prognosis for patients with malignant gliomas has changed little for the last decades. Cancer treatment requires high accuracy in delivering ionizing radiation to reduce toxicity to surrounding tissues. Recently some research has been focused in developing photosensitizing quantum dots for production of radicals upon absorption of visible light. In spite of the fact that visible light is safe, this approach is suitable to treat only superficial tumours. Ionizing radiation (X-rays and gamma rays) penetrate much deeper thus offering a big advantage in treating patients with tumours in internal organs. Such concept of using quantum dots and nanoparticles to yield electrons and radicals in photodynamic and radiation therapies as well their combination is reviewed in this article.
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Affiliation(s)
- Petras Juzenas
- Department of Radiation Biology, Institute for Cancer Research, Norwegian Radium Hospital, Rikshospitalet University Hospital, Montebello, 0310 Oslo, Norway.
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Plaetzer K, Krammer B, Berlanda J, Berr F, Kiesslich T. Photophysics and photochemistry of photodynamic therapy: fundamental aspects. Lasers Med Sci 2008; 24:259-68. [PMID: 18247081 DOI: 10.1007/s10103-008-0539-1] [Citation(s) in RCA: 534] [Impact Index Per Article: 33.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2007] [Accepted: 01/02/2008] [Indexed: 01/22/2023]
Abstract
Photodynamic therapy (PDT) is a treatment modality for cancer and various other diseases. The clinical protocol covers the illumination of target cells (or tissue), which have been loaded with a photoactive drug (photosensitizer). In this review we describe the photophysical and primary photochemical processes that occur during PDT. Interaction of light with tissue results in attenuation of the incident light energy due to reflectance, absorption, scattering, and refraction. Refraction and reflection are reduced by perpendicular light application, whereas absorption can be minimized by the choice of a photosensitizer that absorbs in the far red region of the electromagnetic spectrum. Interaction of light and the photosensitizer can result in degradation, modification or relocalization of the drug, which differently affect the effectiveness of PDT. Photodynamic therapy itself, however, employs the light-induced chemical reactions of the activated photosensitizer (triplet state), resulting in the production of various reactive oxygen species, amongst them singlet oxygen as the primary photochemical product. Based on these considerations, the properties of an ideal photosensitizer for PDT are discussed. According to the clinical experience with PDT, it is proposed that the innovative concept of PDT is most successfully implemented into the mainstream of anticancer therapies by following an application-, i.e. tumor-centered approach with a focus on the actual clinical requirements of the respective tumor type.
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Affiliation(s)
- K Plaetzer
- Department of Molecular Biology, University of Salzburg, Hellbrunnerstrasse 34, 5020, Salzburg, Austria
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34
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Campbell EA, Greenwell R, Anthony JR, Wang S, Lim L, Das K, Sofia HJ, Donohue TJ, Darst SA. A conserved structural module regulates transcriptional responses to diverse stress signals in bacteria. Mol Cell 2007; 27:793-805. [PMID: 17803943 PMCID: PMC2390684 DOI: 10.1016/j.molcel.2007.07.009] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2007] [Revised: 06/12/2007] [Accepted: 07/02/2007] [Indexed: 10/22/2022]
Abstract
A transcriptional response to singlet oxygen in Rhodobacter sphaeroides is controlled by the group IV sigma factor sigma(E) and its cognate anti-sigma ChrR. Crystal structures of the sigma(E)/ChrR complex reveal a modular, two-domain architecture for ChrR. The ChrR N-terminal anti-sigma domain (ASD) binds a Zn(2+) ion, contacts sigma(E), and is sufficient to inhibit sigma(E)-dependent transcription. The ChrR C-terminal domain adopts a cupin fold, can coordinate an additional Zn(2+), and is required for the transcriptional response to singlet oxygen. Structure-based sequence analyses predict that the ASD defines a common structural fold among predicted group IV anti-sigmas. These ASDs are fused to diverse C-terminal domains that are likely involved in responding to specific environmental signals that control the activity of their cognate sigma factor.
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Affiliation(s)
| | - Roger Greenwell
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Jennifer R. Anthony
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Sheng Wang
- The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA
| | - Lionel Lim
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Kalyan Das
- Department of Chemistry and Chemical Biology, Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, NJ 08854, USA
| | - Heidi J. Sofia
- Computational Biology and Bioinformatics, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Timothy J. Donohue
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Seth A. Darst
- The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA
- Correspondence:
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Tavano CL, Donohue TJ. Development of the bacterial photosynthetic apparatus. Curr Opin Microbiol 2006; 9:625-31. [PMID: 17055774 PMCID: PMC2765710 DOI: 10.1016/j.mib.2006.10.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2006] [Accepted: 10/11/2006] [Indexed: 11/29/2022]
Abstract
Anoxygenic photosynthetic bacteria have provided us with crucial insights into the process of solar energy capture, pathways of metabolic and societal importance, specialized differentiation of membrane domains, function or assembly of bioenergetic enzymes, and into the genetic control of these and other activities. Recent insights into the organization of this bioenergetic membrane system, the genetic control of this specialized domain of the inner membrane and the process by which potentially photosynthetic and non-photosynthetic cells protect themselves from an important class of reactive oxygen species will provide an unparalleled understanding of solar energy capture and facilitate the design of solar-powered microbial biorefineries.
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Affiliation(s)
- Christine L Tavano
- Bacteriology Department, University of Wisconsin-Madison, Madison, WI 53706, USA
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Chernonosov AA, Koval VV, Knorre DG, Chernenko AA, Derkacheva VM, Lukyanets EA, Fedorova OS. Conjugates of phthalocyanines with oligonucleotides as reagents for sensitized or catalytic DNA modification. Bioinorg Chem Appl 2006; 2006:63703. [PMID: 17497012 PMCID: PMC1779547 DOI: 10.1155/bca/2006/63703] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2004] [Revised: 12/01/2004] [Accepted: 12/03/2004] [Indexed: 01/12/2023] Open
Abstract
Several conjugates of metallophthalocyanines with deoxyribooligonucleotides were synthesized to investigate sequence-specific modification of DNA by them. Oligonucleotide parts of these conjugates were responsible for the recognition of selected complementary sequences on the DNA target. Metallophthalocyanines were able to induce the DNA modification: phthalocyanines of Zn(II) and Al(III) were active as photosensitizers in the generation of singlet oxygen (1)O(2), while phthalocyanine of Co(II) promoted DNA oxidation by molecular oxygen through the catalysis of formation of reactive oxygen species ((.)O(2) (-), H(2)O(2), OH). Irradiation of the reaction mixture containing either Zn(II)- or Al(III)-tetracarboxyphthalocyanine conjugates of oligonucleotide pd(TCTTCCCA) with light of > 340 nm wavelength (Hg lamp or He/Ne laser) resulted in the modification of the 22-nucleotide target d(TGAATGGGAAGAGGGTCAGGTT). A conjugate of Co(II)-tetracarboxyphthalocyanine with the oligonucleotide was found to modify the DNA target in the presence of O(2) and 2-mercaptoethanol or in the presence of H(2)O(2). Under both sensitized and catalyzed conditions, the nucleotides G(13)-G(15) were mainly modified, providing evidence that the reaction proceeded in the double-stranded oligonucleotide. These results suggest the possible use of phthalocyanine-oligonucleotide conjugates as novel artificial regulators of gene expression and therapeutic agents for treatment of cancer.
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Affiliation(s)
- Alexander A. Chernonosov
- Institute of Chemical Biology and Fundamental
Medicine, Siberian Division of the Russian Academy of Sciences,
Lavrentyev Avenue 8, Novosibirsk 630090, Russia
- Novosibirsk State University, Pyrogova Street 2,
Novosibirsk 630090, Russia
- Institute of Human Ecology, Sovetskii Avenue 18,
Kemerovo 650099, Russia
| | - Vladimir V. Koval
- Institute of Chemical Biology and Fundamental
Medicine, Siberian Division of the Russian Academy of Sciences,
Lavrentyev Avenue 8, Novosibirsk 630090, Russia
- Novosibirsk State University, Pyrogova Street 2,
Novosibirsk 630090, Russia
| | - Dmitrii G. Knorre
- Institute of Chemical Biology and Fundamental
Medicine, Siberian Division of the Russian Academy of Sciences,
Lavrentyev Avenue 8, Novosibirsk 630090, Russia
- Novosibirsk State University, Pyrogova Street 2,
Novosibirsk 630090, Russia
| | - Alexander A. Chernenko
- Institute of Semiconductor Physics, Siberian Division of the Russian Academy of Sciences, Lavrentyev Avenue 13,
Novosibirsk 630090, Russia
| | | | - Eugenii A. Lukyanets
- Organic Intermediates and Dyes Institute, B. Sadovaya 1/4, Moscow 103787, Russia
| | - Olga S. Fedorova
- Institute of Chemical Biology and Fundamental
Medicine, Siberian Division of the Russian Academy of Sciences,
Lavrentyev Avenue 8, Novosibirsk 630090, Russia
- Novosibirsk State University, Pyrogova Street 2,
Novosibirsk 630090, Russia
- *Olga S. Fedorova:
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Nott A, Jung HS, Koussevitzky S, Chory J. Plastid-to-nucleus retrograde signaling. ANNUAL REVIEW OF PLANT BIOLOGY 2006; 57:739-59. [PMID: 16669780 DOI: 10.1146/annurev.arplant.57.032905.105310] [Citation(s) in RCA: 363] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Plant cells store genetic information in the genomes of three organelles: the nucleus, plastid, and mitochondrion. The nucleus controls most aspects of organelle gene expression, development, and function. In return, organelles send signals to the nucleus to control nuclear gene expression, a process called retrograde signaling. This review summarizes our current understanding of plastid-to-nucleus retrograde signaling, which involves multiple, partially redundant signaling pathways. The best studied is a pathway that is triggered by buildup of Mg-ProtoporphyrinIX, the first intermediate in the chlorophyll branch of the tetrapyrrole biosynthetic pathway. In addition, there is evidence for a plastid gene expression-dependent pathway, as well as a third pathway that is dependent on the redox state of photosynthetic electron transport components. Although genetic studies have identified several players involved in signal generation, very little is known of the signaling components or transcription factors that regulate the expression of hundreds of nuclear genes.
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Affiliation(s)
- Ajit Nott
- Plant Biology Laboratory and Howard Hughes Medical Institute, Salk Institute for Biological Studies, La Jolla, California 92037, USA.
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Anthony JR, Warczak KL, Donohue TJ. A transcriptional response to singlet oxygen, a toxic byproduct of photosynthesis. Proc Natl Acad Sci U S A 2005; 102:6502-7. [PMID: 15855269 PMCID: PMC1088386 DOI: 10.1073/pnas.0502225102] [Citation(s) in RCA: 128] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The ability of phototrophs to convert light into biological energy is critical for life on Earth. However, there can be deleterious consequences associated with this bioenergetic conversion, including the production of toxic byproducts. For example, singlet oxygen (1O2) can be formed during photosynthesis by energy transfer from excited triplet-state chlorophyll pigments to O2. By monitoring gene expression and growth in the presence of 1O2, we show that the phototrophic bacterium Rhodobacter sphaeroides mounts a transcriptional response to this reactive oxygen species (ROS) that requires the alternative sigma factor, sigma(E). An increase in sigma(E) activity is seen when cells are exposed to 1O2 generated either by photochemistry within the photosynthetic apparatus or the photosensitizer, methylene blue. Wavelengths of light responsible for the generating triplet-state chlorophyll pigments in the photosynthetic apparatus are sufficient for a sustained increase in sigma(E) activity. Continued exposure to 1O2 is required to maintain this transcriptional response, and other ROS do not cause a similar increase in sigma(E)-dependent gene expression. When a sigma(E) mutant produces low levels of carotenoids, 1O2 is bacteriocidal, suggesting that this response is essential for protecting cells from this ROS. In addition, global gene expression analysis identified approximately 180 genes (approximately 60 operons) whose RNA levels increase > or = 3-fold in cells with increased sigma(E) activity. Gene products encoded by four newly identified sigma(E)-dependent operons are predicted to be involved in stress response, protecting cells from 1O2 damage, or the conservation of energy.
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Affiliation(s)
- Jennifer R Anthony
- Department of Bacteriology, University of Wisconsin, 420 Henry Mall, Madison, WI 53706, USA
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Danon A, Miersch O, Felix G, Camp RGL, Apel K. Concurrent activation of cell death-regulating signaling pathways by singlet oxygen in Arabidopsis thaliana. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2005; 41:68-80. [PMID: 15610350 DOI: 10.1111/j.1365-313x.2004.02276.x] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Upon a dark/light shift the conditional flu mutant of Arabidopsis starts to generate singlet oxygen ((1)O(2)), a non-radical reactive oxygen species that is restricted to the plastid compartment. Immediately after the shift, plants stop growing and develop necrotic lesions. We have established a protoplast system, which allows detection and characterization of the death response in flu induced by the release of (1)O(2). Vitamin B6 that quenches (1)O(2) in fungi was able to protect flu protoplasts from cell death. Blocking ethylene production was sufficient to partially inhibit the death reaction. Similarly, flu mutant seedlings expressing transgenic NahG were partially protected from the death provoked by the release of (1)O(2), indicating a requirement for salicylic acid (SA) in this process, whereas in cells depleted of both, ethylene and SA, the extent of cell death was reduced to the wild-type level. The flu mutant was also crossed with the jasmonic acid (JA)-depleted mutant opr3, and with the JA, OPDA and dinor OPDA (dnOPDA)-depleted dde2-2 mutant. Analysis of the resulting double mutants revealed that in contrast to the JA-induced suppression of H(2)O(2)/superoxide-dependent cell death reported earlier, JA promotes singlet oxygen-mediated cell death in flu, whereas other oxylipins such as OPDA and dnOPDA antagonize this death-inducing activity of JA.
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Affiliation(s)
- Antoine Danon
- Institute of Plant Sciences, Plant Genetics, Swiss Federal Institute of Technology (ETH), CH - 8092 Zürich, Switzerland
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