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Harel I, Chen YR, Ziv I, Singh PP, Heinzer D, Navarro Negredo P, Goshtchevsky U, Wang W, Astre G, Moses E, McKay A, Machado BE, Hebestreit K, Yin S, Sánchez Alvarado A, Jarosz DF, Brunet A. Identification of protein aggregates in the aging vertebrate brain with prion-like and phase-separation properties. Cell Rep 2024; 43:112787. [PMID: 38810650 PMCID: PMC11285089 DOI: 10.1016/j.celrep.2023.112787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 04/23/2023] [Accepted: 06/26/2023] [Indexed: 05/31/2024] Open
Abstract
Protein aggregation, which can sometimes spread in a prion-like manner, is a hallmark of neurodegenerative diseases. However, whether prion-like aggregates form during normal brain aging remains unknown. Here, we use quantitative proteomics in the African turquoise killifish to identify protein aggregates that accumulate in old vertebrate brains. These aggregates are enriched for prion-like RNA-binding proteins, notably the ATP-dependent RNA helicase DDX5. We validate that DDX5 forms aggregate-like puncta in the brains of old killifish and mice. Interestingly, DDX5's prion-like domain allows these aggregates to propagate across many generations in yeast. In vitro, DDX5 phase separates into condensates. Mutations that abolish DDX5 prion propagation also impair the protein's ability to phase separate. DDX5 condensates exhibit enhanced enzymatic activity, but they can mature into inactive, solid aggregates. Our findings suggest that protein aggregates with prion-like properties form during normal brain aging, which could have implications for the age-dependency of cognitive decline.
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Affiliation(s)
- Itamar Harel
- Department of Genetics, Stanford University, Stanford, CA 94305, USA; The Silberman Institute, the Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel.
| | - Yiwen R Chen
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA 94305, USA
| | - Inbal Ziv
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA 94305, USA
| | - Param Priya Singh
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Daniel Heinzer
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | | | - Uri Goshtchevsky
- The Silberman Institute, the Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel
| | - Wei Wang
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
| | - Gwendoline Astre
- The Silberman Institute, the Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel
| | - Eitan Moses
- The Silberman Institute, the Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel
| | - Andrew McKay
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Ben E Machado
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Katja Hebestreit
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Sifei Yin
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA 94305, USA
| | | | - Daniel F Jarosz
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA 94305, USA; Department of Developmental Biology, Stanford University, Stanford, CA 94305, USA.
| | - Anne Brunet
- Department of Genetics, Stanford University, Stanford, CA 94305, USA; Glenn Laboratories for the Biology of Aging, Stanford University, Stanford, CA 94305, USA.
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2
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Huang CC, Chiu TY, Lee TY, Hsieh HJ, Lin CC, Kao LS. Soluble α-synuclein facilitates priming and fusion by releasing Ca 2+ from the thapsigargin-sensitive Ca 2+ pool in PC12 cells. J Cell Sci 2018; 131:jcs.213017. [PMID: 30404828 DOI: 10.1242/jcs.213017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 10/12/2018] [Indexed: 02/01/2023] Open
Abstract
α-Synuclein is associated with Parkinson's disease, and is mainly localized in presynaptic terminals and regulates exocytosis, but its physiological roles remain controversial. Here, we studied the effects of soluble and aggregated α-synuclein on exocytosis, and explored the molecular mechanism by which α-synuclein interacts with regulatory proteins, including Rab3A, Munc13-1 (also known as Unc13a) and Munc18-1 (also known as STXBP1), in order to regulate exocytosis. Through fluorescence recovery after photobleaching experiments, overexpressed α-synuclein in PC12 cells was found to be in a monomeric form, which promotes exocytosis. In contrast, aggregated α-synuclein induced by lactacystin treatment inhibits exocytosis. Our results show that α-synuclein is involved in vesicle priming and fusion. α-Synuclein and phorbol 12-myristate 13-acetate (PMA), which is known to enhance vesicle priming mediated by Rab3A, Munc13-1 and Munc18-1, act on the same population of vesicles, but regulate priming independently. Furthermore, the results show a novel effects of α-synuclein on mobilizing Ca2+ release from thapsigargin-sensitive Ca2+ pools to enhance the ATP-induced [Ca2+]i increase, which enhances vesicle fusion. Our results provide a detailed understanding of the action of α-synuclein during the final steps of exocytosis.
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Affiliation(s)
- Chien-Chang Huang
- Brain Research Center, National Yang-Ming University, Taipei 112, Taiwan, Republic of China.,Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan, Republic of China
| | - Tai-Yu Chiu
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan, Republic of China
| | - Tzu-Ying Lee
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan, Republic of China
| | - Hsin-Jui Hsieh
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan, Republic of China
| | - Chung-Chih Lin
- Brain Research Center, National Yang-Ming University, Taipei 112, Taiwan, Republic of China .,Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan, Republic of China.,Biophotonics Interdisciplinary Research Center, National Yang-Ming University, Taipei 112, Taiwan, Republic of China
| | - Lung-Sen Kao
- Brain Research Center, National Yang-Ming University, Taipei 112, Taiwan, Republic of China .,Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan, Republic of China
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3
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Nevzglyadova OV, Mikhailova EV, Artemov AV, Ozerova YE, Ivanova PA, Golomidov IM, Bolshakova OI, Zenin VV, Kostyleva EI, Soidla TR, Sarantseva SV. Yeast red pigment modifies cloned human α-synuclein pathogenesis in Parkinson disease models in Saccharomyces cerevisiae and Drosophila melanogaster. Neurochem Int 2018; 120:172-181. [PMID: 30099122 DOI: 10.1016/j.neuint.2018.08.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 06/27/2018] [Accepted: 08/06/2018] [Indexed: 12/21/2022]
Abstract
Recently, we identified the yeast red pigment (RP), a polymer of 1-(5'-Phosphoribosyl)-5-aminoimidazole, as a novel potential anti-amyloid agent for the therapy of neurodegenerative diseases. The purpose of this study was to further validate RP for treatment of Parkinson's disease (PD) and to clarify molecular mechanisms involved in the reduction of amyloid cytotoxicity. We investigated RP effects in vivo using Saccharomyces cerevisiae and Drosophila melanogaster PD models. Western blot analysis revealed reduction in the levels of insoluble α-synuclein in both models, while soluble α-synuclein decreased only in Drosophila. In both models RP significantly reduced α-synuclein cytotoxicity, as was revealed by immunohistochemistry in Drosophila (p < 0.001, n = 27 flies per genotype/assay) and by flow cytometry in yeast (p < 0.05). Data obtained from the yeast PD model suggests that RP antitoxic effects are associated with a drop in ROS accumulation, and slower cellular transition from the early to late apoptotic stage. Using Drosophila brain tissue sections, we have demonstrated that RP helps to compensate for an α-synuclein-mediated reduction in the number of dopaminergic neurons and leads to better performance in animal climbing tests (p < 0.001, n = 120-150 flies per genotype/assay). Taken together, these results demonstrate the potential of RP for the treatment of PD, at least in model systems.
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Affiliation(s)
- O V Nevzglyadova
- Institute of Cytology of RAS, St. Petersburg, Russian Federation
| | - E V Mikhailova
- Institute of Cytology of RAS, St. Petersburg, Russian Federation
| | - A V Artemov
- Institute of Cytology of RAS, St. Petersburg, Russian Federation
| | - Y E Ozerova
- Institute of Cytology of RAS, St. Petersburg, Russian Federation
| | - P A Ivanova
- Institute of Cytology of RAS, St. Petersburg, Russian Federation
| | - I M Golomidov
- Petersburg Nuclear Physics Institute of National Research Centre, "Kurchatov Institute", Gatchina, Russian Federation
| | - O I Bolshakova
- Petersburg Nuclear Physics Institute of National Research Centre, "Kurchatov Institute", Gatchina, Russian Federation
| | - V V Zenin
- Institute of Cytology of RAS, St. Petersburg, Russian Federation
| | - E I Kostyleva
- Institute of Cytology of RAS, St. Petersburg, Russian Federation
| | - T R Soidla
- Institute of Cytology of RAS, St. Petersburg, Russian Federation
| | - S V Sarantseva
- Petersburg Nuclear Physics Institute of National Research Centre, "Kurchatov Institute", Gatchina, Russian Federation.
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4
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Lara JA, Burciaga-Monge A, Chávez A, Revés M, Lavilla R, Arró M, Boronat A, Altabella T, Ferrer A. Identification and Characterization of Sterol Acyltransferases Responsible for Steryl Ester Biosynthesis in Tomato. FRONTIERS IN PLANT SCIENCE 2018; 9:588. [PMID: 29868054 PMCID: PMC5952233 DOI: 10.3389/fpls.2018.00588] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2018] [Accepted: 04/16/2018] [Indexed: 05/17/2023]
Abstract
Steryl esters (SEs) serve as a storage pool of sterols that helps to maintain proper levels of free sterols (FSs) in cell membranes throughout plant growth and development, and participates in the recycling of FSs and fatty acids released from cell membranes in aging tissues. SEs are synthesized by sterol acyltransferases, a family of enzymes that catalyze the transfer of fatty acil groups to the hydroxyl group at C-3 position of the sterol backbone. Sterol acyltransferases are categorized into acyl-CoA:sterol acyltransferases (ASAT) and phospholipid:sterol acyltransferases (PSAT) depending on whether the fatty acyl donor substrate is a long-chain acyl-CoA or a phospolipid. Until now, only Arabidopsis ASAT and PSAT enzymes (AtASAT1 and AtPSAT1) have been cloned and characterized in plants. Here we report the identification, cloning, and functional characterization of the tomato (Solanum lycopersicum cv. Micro-Tom) orthologs. SlPSAT1 and SlASAT1 were able to restore SE to wild type levels in the Arabidopsis psat1-2 and asat1-1 knock-out mutants, respectively. Expression of SlPSAT1 in the psat1-2 background also prevented the toxicity caused by an external supply of mevalonate and the early senescence phenotype observed in detached leaves of this mutant, whereas expression of SlASAT1 in the asat1-1 mutant revealed a clear substrate preference of the tomato enzyme for the sterol precursors cycloartenol and 24-methylene cycloartanol. Subcellular localization studies using fluorescently tagged SlPSAT1 and SlASAT1 proteins revealed that SlPSAT1 localize in cytoplasmic lipid droplets (LDs) while, in contrast to the endoplasmic reticulum (ER) localization of AtASAT1, SlASAT1 resides in the plasma membrane (PM). The possibility that PM-localized SlASAT1 may act catalytically in trans on their sterol substrates, which are presumably embedded in the ER membrane, is discussed. The widespread expression of SlPSAT1 and SlASAT1 genes in different tomato organs together with their moderate transcriptional response to several stresses suggests a dual role of SlPSAT1 and SlASAT1 in tomato plant and fruit development and the adaptive responses to stress. Overall, this study contributes to enlarge the current knowledge on plant sterol acyltransferases and set the basis for further studies aimed at understanding the role of SE metabolism in tomato plant growth and development.
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Affiliation(s)
- Juan A. Lara
- Plant Metabolism and Metabolic Engineering Program, Centre for Research in Agricultural Genomics (CRAG) (CSIC-IRTA-UAB-UB), Campus Autonomous University of Barcelona, Cerdanyola del Vallès, Spain
- Present address: Juan A. Lara, School of Agritechnological Sciences (Extensión Cuauhtémoc), Autonomous University of Chihuahua, Chihuahua, Mexico
| | - Alma Burciaga-Monge
- Plant Metabolism and Metabolic Engineering Program, Centre for Research in Agricultural Genomics (CRAG) (CSIC-IRTA-UAB-UB), Campus Autonomous University of Barcelona, Cerdanyola del Vallès, Spain
| | - Angel Chávez
- Plant Metabolism and Metabolic Engineering Program, Centre for Research in Agricultural Genomics (CRAG) (CSIC-IRTA-UAB-UB), Campus Autonomous University of Barcelona, Cerdanyola del Vallès, Spain
| | - Marc Revés
- Laboratory of Medicinal Chemistry, Institute of Biomedicine University of Barcelona, Faculty of Pharmacy and Food Sciences, University of Barcelona, Barcelona, Spain
| | - Rodolfo Lavilla
- Laboratory of Medicinal Chemistry, Institute of Biomedicine University of Barcelona, Faculty of Pharmacy and Food Sciences, University of Barcelona, Barcelona, Spain
| | - Monserrat Arró
- Plant Metabolism and Metabolic Engineering Program, Centre for Research in Agricultural Genomics (CRAG) (CSIC-IRTA-UAB-UB), Campus Autonomous University of Barcelona, Cerdanyola del Vallès, Spain
- Department of Biochemistry and Physiology, Faculty of Pharmacy and Food Sciences, University of Barcelona, Barcelona, Spain
| | - Albert Boronat
- Plant Metabolism and Metabolic Engineering Program, Centre for Research in Agricultural Genomics (CRAG) (CSIC-IRTA-UAB-UB), Campus Autonomous University of Barcelona, Cerdanyola del Vallès, Spain
- Department of Biochemistry and Molecular Biomedicine, Faculty of Biology, University of Barcelona, Barcelona, Spain
| | - Teresa Altabella
- Plant Metabolism and Metabolic Engineering Program, Centre for Research in Agricultural Genomics (CRAG) (CSIC-IRTA-UAB-UB), Campus Autonomous University of Barcelona, Cerdanyola del Vallès, Spain
- Department of Biology, Healthcare, and the Environment, Faculty of Pharmacy and Food Sciences, University of Barcelona, Barcelona, Spain
- *Correspondence: Teresa Altabella, Albert Ferrer,
| | - Albert Ferrer
- Plant Metabolism and Metabolic Engineering Program, Centre for Research in Agricultural Genomics (CRAG) (CSIC-IRTA-UAB-UB), Campus Autonomous University of Barcelona, Cerdanyola del Vallès, Spain
- Department of Biochemistry and Physiology, Faculty of Pharmacy and Food Sciences, University of Barcelona, Barcelona, Spain
- *Correspondence: Teresa Altabella, Albert Ferrer,
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5
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Zhao X, Rodriguez R, Silberman RE, Ahearn JM, Saidha S, Cummins KC, Eisenberg E, Greene LE. Heat shock protein 104 (Hsp104)-mediated curing of [ PSI+] yeast prions depends on both [ PSI+] conformation and the properties of the Hsp104 homologs. J Biol Chem 2017; 292:8630-8641. [PMID: 28373280 DOI: 10.1074/jbc.m116.770719] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 03/29/2017] [Indexed: 11/06/2022] Open
Abstract
Prions arise from proteins that have two possible conformations: properly folded and non-infectious or misfolded and infectious. The [PSI+] yeast prion, which is the misfolded and self-propagating form of the translation termination factor eRF3 (Sup35), can be cured of its infectious conformation by overexpression of Hsp104, which helps dissolve the prion seeds. This dissolution depends on the trimming activity of Hsp104, which reduces the size of the prion seeds without increasing their number. To further understand the relationship between trimming and curing, trimming was followed by measuring the loss of GFP-labeled Sup35 foci from both strong and weak [PSI+] variants; the former variant has more seeds and less soluble Sup35 than the latter. Overexpression of Saccharomyces cerevisiae Hsp104 (Sc-Hsp104) trimmed the weak [PSI+] variants much faster than the strong variants and cured the weak variants an order of magnitude faster than the strong variants. Overexpression of the fungal Hsp104 homologs from Schizosaccharomyces pombe (Sp-Hsp104) or Candida albicans (Ca-Hsp104) also trimmed and cured the weak variants, but interestingly, it neither trimmed nor cured the strong variants. These results show that, because Sc-Hsp104 has greater trimming activity than either Ca-Hsp104 or Sp-Hsp104, it cures both the weak and strong variants, whereas Ca-Hsp104 and Sp-Hsp104 only cure the weak variants. Therefore, curing by Hsp104 overexpression depends on both the trimming ability of the fungal Hsp104 homolog and the strength of the [PSI+] variant: the greater the trimming activity of the Hsp104 homolog and the weaker the variant, the greater the curing.
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Affiliation(s)
- Xiaohong Zhao
- From the Laboratory of Cell Biology, NHLBI, National Institutes of Health, Bethesda, Maryland 20892-0301
| | - Ramon Rodriguez
- From the Laboratory of Cell Biology, NHLBI, National Institutes of Health, Bethesda, Maryland 20892-0301
| | - Rebecca E Silberman
- From the Laboratory of Cell Biology, NHLBI, National Institutes of Health, Bethesda, Maryland 20892-0301
| | - Joseph M Ahearn
- From the Laboratory of Cell Biology, NHLBI, National Institutes of Health, Bethesda, Maryland 20892-0301
| | - Sheela Saidha
- From the Laboratory of Cell Biology, NHLBI, National Institutes of Health, Bethesda, Maryland 20892-0301
| | - Kaelyn C Cummins
- From the Laboratory of Cell Biology, NHLBI, National Institutes of Health, Bethesda, Maryland 20892-0301
| | - Evan Eisenberg
- From the Laboratory of Cell Biology, NHLBI, National Institutes of Health, Bethesda, Maryland 20892-0301
| | - Lois E Greene
- From the Laboratory of Cell Biology, NHLBI, National Institutes of Health, Bethesda, Maryland 20892-0301
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6
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Kryndushkin D, Edskes HK, Shewmaker FP, Wickner RB. Prions. Cold Spring Harb Protoc 2017; 2017:2017/2/pdb.top077586. [PMID: 28148884 DOI: 10.1101/pdb.top077586] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Infectious proteins (prions) are usually self-templating filamentous protein polymers (amyloids). Yeast prions are genes composed of protein and, like the multiple alleles of DNA-based genes, can have an array of "variants," each a distinct self-propagating amyloid conformation. Like the lethal mammalian prions and amyloid diseases, yeast prions may be lethal, or only mildly detrimental, and show an array of phenotypes depending on the protein involved and the prion variant. Yeast prions are models for both rare mammalian prion diseases and for several very common amyloidoses such as Alzheimer's disease, type 2 diabetes, and Parkinson's disease. Here, we describe their detection and characterization using genetic, cell biological, biochemical, and physical methods.
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Affiliation(s)
- Dmitry Kryndushkin
- Department of Pharmacology, Uniformed Services University of Health Sciences, Bethesda, Maryland 20814
| | - Herman K Edskes
- Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0830
| | - Frank P Shewmaker
- Department of Pharmacology, Uniformed Services University of Health Sciences, Bethesda, Maryland 20814
| | - Reed B Wickner
- Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0830
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7
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Ramirez-Estrada K, Castillo N, Lara JA, Arró M, Boronat A, Ferrer A, Altabella T. Tomato UDP-Glucose Sterol Glycosyltransferases: A Family of Developmental and Stress Regulated Genes that Encode Cytosolic and Membrane-Associated Forms of the Enzyme. FRONTIERS IN PLANT SCIENCE 2017. [PMID: 28649260 PMCID: PMC5465953 DOI: 10.3389/fpls.2017.00984] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Sterol glycosyltransferases (SGTs) catalyze the glycosylation of the free hydroxyl group at C-3 position of sterols to produce sterol glycosides. Glycosylated sterols and free sterols are primarily located in cell membranes where in combination with other membrane-bound lipids play a key role in modulating their properties and functioning. In contrast to most plant species, those of the genus Solanum contain very high levels of glycosylated sterols, which in the case of tomato may account for more than 85% of the total sterol content. In this study, we report the identification and functional characterization of the four members of the tomato (Solanum lycopersicum cv. Micro-Tom) SGT gene family. Expression of recombinant SlSGT proteins in E. coli cells and N. benthamiana leaves demonstrated the ability of the four enzymes to glycosylate different sterol species including cholesterol, brassicasterol, campesterol, stigmasterol, and β-sitosterol, which is consistent with the occurrence in their primary structure of the putative steroid-binding domain found in steroid UDP-glucuronosyltransferases and the UDP-sugar binding domain characteristic for a superfamily of nucleoside diphosphosugar glycosyltransferases. Subcellular localization studies based on fluorescence recovery after photobleaching and cell fractionation analyses revealed that the four tomato SGTs, like the Arabidopsis SGTs UGT80A2 and UGT80B1, localize into the cytosol and the PM, although there are clear differences in their relative distribution between these two cell fractions. The SlSGT genes have specialized but still largely overlapping expression patterns in different organs of tomato plants and throughout the different stages of fruit development and ripening. Moreover, they are differentially regulated in response to biotic and abiotic stress conditions. SlSGT4 expression increases markedly in response to osmotic, salt, and cold stress, as well as upon treatment with abscisic acid and methyl jasmonate. Stress-induced SlSGT2 expression largely parallels that of SlSGT4. On the contrary, SlSGT1 and SlSGT3 expression remains almost unaltered under the tested stress conditions. Overall, this study contributes to broaden the current knowledge on plant SGTs and provides support to the view that tomato SGTs play overlapping but not completely redundant biological functions involved in mediating developmental and stress responses.
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Affiliation(s)
- Karla Ramirez-Estrada
- Plant Metabolism and Metabolic Engineering Program, Centre for Research in Agricultural Genomics (CRAG) (CSIC-IRTA-UAB-UB)Barcelona, Spain
| | - Nídia Castillo
- Plant Metabolism and Metabolic Engineering Program, Centre for Research in Agricultural Genomics (CRAG) (CSIC-IRTA-UAB-UB)Barcelona, Spain
| | - Juan A. Lara
- Plant Metabolism and Metabolic Engineering Program, Centre for Research in Agricultural Genomics (CRAG) (CSIC-IRTA-UAB-UB)Barcelona, Spain
| | - Monserrat Arró
- Plant Metabolism and Metabolic Engineering Program, Centre for Research in Agricultural Genomics (CRAG) (CSIC-IRTA-UAB-UB)Barcelona, Spain
- Department of Biochemistry and Physiology, Faculty of Pharmacy and Food Sciences, University of BarcelonaBarcelona, Spain
| | - Albert Boronat
- Plant Metabolism and Metabolic Engineering Program, Centre for Research in Agricultural Genomics (CRAG) (CSIC-IRTA-UAB-UB)Barcelona, Spain
- Department of Biochemistry and Molecular Biomedicine, Faculty of Biology, University of BarcelonaBarcelona, Spain
| | - Albert Ferrer
- Plant Metabolism and Metabolic Engineering Program, Centre for Research in Agricultural Genomics (CRAG) (CSIC-IRTA-UAB-UB)Barcelona, Spain
- Department of Biochemistry and Physiology, Faculty of Pharmacy and Food Sciences, University of BarcelonaBarcelona, Spain
- *Correspondence: Teresa Altabella, Albert Ferrer,
| | - Teresa Altabella
- Plant Metabolism and Metabolic Engineering Program, Centre for Research in Agricultural Genomics (CRAG) (CSIC-IRTA-UAB-UB)Barcelona, Spain
- Department of Biology, Healthcare and the Environment, Faculty of Pharmacy and Food Sciences, University of BarcelonaBarcelona, Spain
- *Correspondence: Teresa Altabella, Albert Ferrer,
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8
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Ramírez-Estrada K, Altabella T, Onrubia M, Moyano E, Notredame C, Osuna L, Vanden Bossche R, Goossens A, Cusido RM, Palazon J. Transcript profiling of jasmonate-elicited Taxus cells reveals a β-phenylalanine-CoA ligase. PLANT BIOTECHNOLOGY JOURNAL 2016; 14:85-96. [PMID: 25899320 DOI: 10.1111/pbi.12359] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Revised: 01/28/2015] [Accepted: 02/16/2015] [Indexed: 05/22/2023]
Abstract
Plant cell cultures constitute eco-friendly biotechnological platforms for the production of plant secondary metabolites with pharmacological activities, as well as a suitable system for extending our knowledge of secondary metabolism. Despite the high added value of taxol and the importance of taxanes as anticancer compounds, several aspects of their biosynthesis remain unknown. In this work, a genomewide expression analysis of jasmonate-elicited Taxus baccata cell cultures by complementary DNA-amplified fragment length polymorphism (cDNA-AFLP) indicated a correlation between an extensive elicitor-induced genetic reprogramming and increased taxane production in the targeted cultures. Subsequent in silico analysis allowed us to identify 15 genes with a jasmonate-induced differential expression as putative candidates for genes encoding enzymes involved in five unknown steps of taxane biosynthesis. Among them, the TB768 gene showed a strong homology, including a very similar predicted 3D structure, with other genes previously reported to encode acyl-CoA ligases, thus suggesting a role in the formation of the taxol lateral chain. Functional analysis confirmed that the TB768 gene encodes an acyl-CoA ligase that localizes to the cytoplasm and is able to convert β-phenylalanine, as well as coumaric acid, into their respective derivative CoA esters. β-phenylalanyl-CoA is attached to baccatin III in one of the last steps of the taxol biosynthetic pathway. The identification of this gene will contribute to the establishment of sustainable taxol production systems through metabolic engineering or synthetic biology approaches.
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Affiliation(s)
- Karla Ramírez-Estrada
- Secció de Fisiologia Vegetal, Facultat de Farmacia, Universitat de Barcelona, Barcelona, Spain
| | - Teresa Altabella
- Secció de Fisiologia Vegetal, Facultat de Farmacia, Universitat de Barcelona, Barcelona, Spain
- Center for Research in Agricultural Genomics (CRAG) (CSIC-IRTA-UAB-UB), Cerdanyola, Barcelona, Spain
| | - Miriam Onrubia
- Departament de Ciències Experimentals i de Salut, Universitat Pompeu Fabra, Barcelona, Spain
| | - Elisabeth Moyano
- Departament de Ciències Experimentals i de Salut, Universitat Pompeu Fabra, Barcelona, Spain
| | - Cedric Notredame
- Departament de Ciències Experimentals i de Salut, Universitat Pompeu Fabra, Barcelona, Spain
- Comparative Bioinformatics, Centre for Genomic Regulation (CRG), Barcelona, Spain
| | - Lidia Osuna
- Centro de Investigación Biomédica del Sur, Instituto Mexicano del Seguro Social (IMSS), Xochitepec, Mexico
| | - Robin Vanden Bossche
- Department of Plant Systems Biology, VIB, Ghent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
| | - Alain Goossens
- Department of Plant Systems Biology, VIB, Ghent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
| | - Rosa M Cusido
- Secció de Fisiologia Vegetal, Facultat de Farmacia, Universitat de Barcelona, Barcelona, Spain
| | - Javier Palazon
- Secció de Fisiologia Vegetal, Facultat de Farmacia, Universitat de Barcelona, Barcelona, Spain
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9
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Dissecting protein reaction dynamics in living cells by fluorescence recovery after photobleaching. Nat Protoc 2015; 10:660-80. [DOI: 10.1038/nprot.2015.042] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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10
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Abstract
Lambdoid phage 21 uses a pinholin-signal anchor release endolysin strategy to effect temporally regulated host lysis. In this strategy, the pinholin S(21)68 accumulates harmlessly in the bilayer until suddenly triggering to form lethal membrane lesions, consisting of S(21)68 heptamers with central pores <2 nm in diameter. The membrane depolarization caused by these pores activates the muralytic endolysin, R(21), leading immediately to peptidoglycan degradation. The lethal S(21)68 complexes have been designated as pinholes to distinguish from the micrometer-scale holes formed by canonical holins. Here, we used GFP fusions of WT and mutant forms of S(21)68 to show that the holin accumulates uniformly throughout the membrane until the time of triggering, when it suddenly redistributes into numerous small foci (rafts). Raft formation correlates with the depletion of the proton motive force, which is indicated by the potential-sensitive dye bis-(1,3-dibutylbarbituric acid)pentamethine oxonol. By contrast, GFP fusions of either antiholin variant irsS(21)68, which only forms inactive dimers, or nonlethal mutant S(21)68(S44C), which is blocked at an activated dimer stage of the pinhole formation pathway, were both blocked in a state of uniform distribution. In addition, fluorescence recovery after photobleaching revealed that, although the antiholin irsS(21)68-GFP fusion was highly mobile in the membrane (even when the proton motive force was depleted), more than one-half of the S(21)68-GFP molecules were immobile, and the rest were in mobile states with a much lower diffusion rate than the rate of irsS(21)68-GFP. These results suggest a model in which, after transiting into an oligomeric state, S(21)68 migrates into rafts with heterogeneous sizes, within which the final pinholes form.
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11
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Winkler J, Tyedmers J, Bukau B, Mogk A. Hsp70 targets Hsp100 chaperones to substrates for protein disaggregation and prion fragmentation. ACTA ACUST UNITED AC 2012; 198:387-404. [PMID: 22869599 PMCID: PMC3413357 DOI: 10.1083/jcb.201201074] [Citation(s) in RCA: 177] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
The Hsp70 system recruits ClpB/Hsp104 to the surface of stress-induced protein aggregates and prion fibrils. Hsp100 and Hsp70 chaperones in bacteria, yeast, and plants cooperate to reactivate aggregated proteins. Disaggregation relies on Hsp70 function and on ATP-dependent threading of aggregated polypeptides through the pore of the Hsp100 AAA+ hexamer. In yeast, both chaperones also promote propagation of prions by fibril fragmentation, but their functional interplay is controversial. Here, we demonstrate that Hsp70 chaperones were essential for species-specific targeting of their Hsp100 partner chaperones ClpB and Hsp104, respectively, to heat-induced protein aggregates in vivo. Hsp70 inactivation in yeast also abrogated Hsp104 targeting to almost all prions tested and reduced fibril mobility, which indicates that fibril fragmentation by Hsp104 requires Hsp70. The Sup35 prion was unique in allowing Hsp70-independent association of Hsp104 via its N-terminal domain, which, however, was nonproductive. Hsp104 overproduction even outcompeted Hsp70 for Sup35 prion binding, which explains why this condition prevented Sup35 fragmentation and caused prion curing. Our findings indicate a conserved mechanism of Hsp70–Hsp100 cooperation at the surface of protein aggregates and prion fibrils.
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Affiliation(s)
- Juliane Winkler
- Center for Molecular Biology of the University of Heidelberg and German Cancer Research Center, DKFZ-ZMBH Alliance, Universität Heidelberg, Heidelberg D-69120, Germany
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12
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Localization of HET-S to the cell periphery, not to [Het-s] aggregates, is associated with [Het-s]-HET-S toxicity. Mol Cell Biol 2011; 32:139-53. [PMID: 22037764 DOI: 10.1128/mcb.06125-11] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Prion diseases are associated with accumulation of the amyloid form of the prion protein, but the mechanisms of toxicity are unknown. Amyloid toxicity is also associated with fungal prions. In Podospora anserina, the simultaneous presence of [Het-s] prion and its allelic protein HET-S causes cell death in a self-/nonself-discrimination process. Here, using the prion form of a fragment of HET-s ([PrD(157)(+)]), we show that [Het-s]-HET-S toxicity can be faithfully recapitulated in yeast. Overexpression of Hsp40 chaperone, Sis1, rescues this toxicity by curing cells of [PrD(157)(+)]. We find no evidence for toxic [PrD(157)(+)] conformers in the presence of HET-S. Instead, [PrD(157)(+)] appears to seed HET-S to accumulate at the cell periphery and to form aggregates distinct from visible [PrD(157)(+)] aggregates. Furthermore, HET-S mutants that cause HET-S to be sequestered into [PrD(157)(+)] prion aggregates are not toxic. The localization of HET-S at the cell periphery and its association with cell death was also observed in the native host Podospora anserina. Thus, upon interaction with [Het-s], HET-S localizes to the cell periphery, and this relocalization, rather than the formation of mixed HET-s/HET-S aggregates, is associated with toxicity.
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13
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Tsuji T, Kawai-Noma S, Pack CG, Terajima H, Yajima J, Nishizaka T, Kinjo M, Taguchi H. Single-particle tracking of quantum dot-conjugated prion proteins inside yeast cells. Biochem Biophys Res Commun 2011; 405:638-43. [PMID: 21277285 DOI: 10.1016/j.bbrc.2011.01.083] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2011] [Accepted: 01/24/2011] [Indexed: 12/15/2022]
Abstract
Yeast is a model eukaryote with a variety of biological resources. Here we developed a method to track a quantum dot (QD)-conjugated protein in the budding yeast Saccharomyces cerevisiae. We chemically conjugated QDs with the yeast prion Sup35, incorporated them into yeast spheroplasts, and tracked the motions by conventional two-dimensional or three-dimensional tracking microscopy. The method paves the way toward the individual tracking of proteins of interest inside living yeast cells.
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Affiliation(s)
- Toshikazu Tsuji
- Department of Biomolecular Engineering, Graduate School of Biosciences and Biotechnology, Tokyo Institute of Technology, B56, 4259 Nagatsuta, Midori-ku, Yokohama 226-8501, Japan
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14
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Seidel R, Engelhard M. Chemical biology of prion protein: tools to bridge the in vitro/vivo interface. Top Curr Chem (Cham) 2011; 305:199-223. [PMID: 21769714 DOI: 10.1007/128_2011_201] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Research on prion protein (PrP) and pathogenic prion has been very intensive because of its importance as model system for neurodegenerative diseases. One important aspect of this research has been the application of chemical biology tools. In this review we describe new developments like native chemical ligation (NCL) and expressed protein ligation (EPL) for the synthesis and semisynthesis of proteins in general and PrP in particular. These techniques allow the synthesis of designed tailor made analogs which can be used in conjunction with modern biophysical methods like fluorescence spectroscopy, solid state Nuclear Magnetic Resonance (ssNMR), and Electron Paramagnetic Resonance (EPR). Another aspect of prion research is concerned with the interaction of PrP with small organic molecules and metals. The results are critically reviewed and put into perspective of their implication for PrP function.
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Affiliation(s)
- Ralf Seidel
- Max Planck Institut für Molekulare Physiologie, Otto-Hahn-Str. 11, 44227, Dortmund, Germany
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15
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Fleming TC, Shin JY, Lee SH, Becker E, Huang KC, Bustamante C, Pogliano K. Dynamic SpoIIIE assembly mediates septal membrane fission during Bacillus subtilis sporulation. Genes Dev 2010; 24:1160-72. [PMID: 20516200 PMCID: PMC2878653 DOI: 10.1101/gad.1925210] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2010] [Accepted: 04/15/2010] [Indexed: 10/19/2022]
Abstract
SpoIIIE is an FtsK-related protein that transports the forespore chromosome across the Bacillus subtilis sporulation septum. We use membrane photobleaching and protoplast assays to demonstrate that SpoIIIE is required for septal membrane fission in the presence of trapped DNA, and that DNA is transported across separate daughter cell membranes, suggesting that SpoIIIE forms a channel that partitions the daughter cell membranes. Our results reveal a close correlation between septal membrane fission and the assembly of a stable SpoIIIE translocation complex at the septal midpoint. Time-lapse epifluorescence, total internal reflection fluorescence (TIRF) microscopy, and live-cell photoactivation localization microscopy (PALM) demonstrate that the SpoIIIE transmembrane domain mediates dynamic localization to active division sites, whereas the assembly of a stable focus also requires the cytoplasmic domain. The transmembrane domain fails to completely separate the membrane, and it assembles unstable foci. TIRF microscopy and biophysical modeling of fluorescence recovery after photobleaching (FRAP) data suggest that this unstable protein transitions between disassembled and assembled oligomeric states. We propose a new model for the role of SpoIIIE assembly in septal membrane fission that has strong implications for how the chromosome terminus crosses the septum.
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Affiliation(s)
- Tinya C. Fleming
- Division of Biological Sciences, University of California at San Diego, La Jolla, California 92093, USA
| | - Jae Yen Shin
- Department of Physics, University of California at Berkeley, Berkeley, California 94720, USA
- Howard Hughes Medical Institute, University of California at Berkeley, Berkeley, California 94720, USA
| | - Sang-Hyuk Lee
- Department of Physics, University of California at Berkeley, Berkeley, California 94720, USA
- Physical Bioscience Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Eric Becker
- Division of Biological Sciences, University of California at San Diego, La Jolla, California 92093, USA
| | - Kerwyn Casey Huang
- Department of Bioengineering, Stanford University, Stanford, California 94305, USA
| | - Carlos Bustamante
- Department of Physics, University of California at Berkeley, Berkeley, California 94720, USA
- Howard Hughes Medical Institute, University of California at Berkeley, Berkeley, California 94720, USA
- Physical Bioscience Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, California 94720, USA
- Department of Chemistry, University of California at Berkeley, Berkeley, California 94720, USA
| | - Kit Pogliano
- Division of Biological Sciences, University of California at San Diego, La Jolla, California 92093, USA
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16
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Abstract
Prions are infectious proteins, in which self-propagating amyloid conformations of proteins are transmitted. The budding yeast Saccharomyces cerevisiae, one of the best-studied model eukaryotes, also has prions, and thus provides a tractable model system with which to understand the mechanisms of prion phenomena. The yeast prions are protein-based heritable elements, such as [PSI(+)], in which aggregates of prion proteins are transmitted to daughter cells in a non-Mendelian manner. Although the genetic approaches preceded the yeast prion studies, recent investigations of the dynamic aspects of the prion proteins have unraveled the molecular mechanisms by which prions are propagated and transmitted. In particular, several lines of evidence have revealed that the oligomeric species of prion proteins dispersed in the cytoplasm are critical for the transmission. This review summarizes the topics on the transmissible entities of yeast prions, focusing mainly on the Sup35 protein in [PSI(+)].
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Affiliation(s)
- Hideki Taguchi
- Department of Medical Genome Sciences, Graduate School of Frontier Sciences, University of Tokyo, Kashiwanoha, Kashiwa, Chiba, Japan.
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17
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Kawai-Noma S, Pack CG, Tsuji T, Kinjo M, Taguchi H. Single mother-daughter pair analysis to clarify the diffusion properties of yeast prion Sup35 in guanidine-HCl-treated [PSI] cells. Genes Cells 2009; 14:1045-54. [PMID: 19674118 DOI: 10.1111/j.1365-2443.2009.01333.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The yeast prion [PSI(+)] is a protein-based heritable element, in which aggregates of Sup35 protein are transmitted to daughter cells in a non-Mendelian manner. To elucidate the mechanism of the transmission, we have developed methods to directly analyse the dynamics of Sup35 fused with GFP in single mother-daughter pairs. As it is known that the treatment of yeast cells with guanidine hydrochloride (GuHCl) cures [PSI(+)] by perturbing Hsp104, a prion-remodelling factor, we analysed the diffusion profiles of Sup35-GFP in GuHCl-treated [PSI(+)] cells using fluorescence correlation spectroscopy (FCS). FCS analyses revealed that Sup35-GFP diffusion in the daughter cells was faster; that is, the Sup35-GFP particle was smaller, than that in the mother [PSI(+)] cells, and it eventually reached the diffusion profiles in [psi(-)] cells. We then analysed the flux of Sup35-GFP oligomers from mother to daughter [PSI(+)] cells in the presence of GuHCl, using a modified fluorescent recovery after photobleaching technique, and found that the flux of the diffuse oligomers was completely inhibited. The noninvasive methods described here can be applied to other protein-based transmissible systems inside living cells.
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Affiliation(s)
- Shigeko Kawai-Noma
- Department of Medical Genome Sciences, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Chiba 277-8562, Japan
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18
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Abstract
Fluorescent live cell imaging has recently been used in numerous studies to examine prions in yeast. These fluorescence studies take advantage of the fact that unlike the normally folded form, the misfolded amyloid form of the prion protein is aggregated. The studies have used fluorescence to identify new prions, to study the transmission of prion from mother to daughter, and to understand the role of molecular chaperones in this transmission. The use of fluorescence imaging complements the more standard methods used to study prion propagation. This review discusses the various studies that have taken advantage of fluorescence imaging technique particularly in regard to understanding the transmission and curing of the [PSI(+)], the prion form of the translation termination factor Sup35p.
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Affiliation(s)
- Lois E Greene
- Laboratory of Cell Biology, NHLBI, NIH, Bethesda, MD 20892-0301, USA.
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19
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Zhang LC, Chen YF, Chen WL, Zhang CC. Existence of periplasmic barriers preventing green fluorescent protein diffusion from cell to cell in the cyanobacterium Anabaena sp. strain PCC 7120. Mol Microbiol 2008; 70:814-23. [PMID: 18990181 DOI: 10.1111/j.1365-2958.2008.06476.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
When deprived of combined nitrogen, the filamentous cyanobacterium Anabaena PCC 7120 relies on intercellular cooperation involving two cell types: nitrogen-fixing heterocysts and photosynthetic vegetative cells. Heterocysts send fixed nitrogen to vegetative cells over long distances along the filament, receiving a reduced carbon source from them. These intercellular exchanges might involve a continuous periplasm along the filament or cytoplasm-to-cytoplasm conduits or both. In the present study, the green fluorescent protein (GFP) was fused to a twin-arginine translocation signal sequence, which exported GFP to the periplasm of either a heterocyst using the heterocyst-specific promoters PhepA and PpatB or to the periplasm of vegetative cells using the vegetative cell-specific promoter PrbcL. Using the techniques of FRAP (fluorescence recovery after photobleaching) and FLIP (fluorescence loss in photobleaching), we found no evidence for intercellular diffusion of GFP through the periplasm, either from a heterocyst to vegetative cells or vice versa, or among vegetative cells. GFP could diffuse within the periplasm of the producing cell, but the diffusion stopped at the cell border. GFP diffusion could occur between two dividing cells before septum closure. This study indicates that barriers exist at the periplasmic space to prevent free GFP diffusion across cell border along the filament.
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Affiliation(s)
- Li-Chen Zhang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
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20
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Jayagopal A, Stone GP, Haselton FR. Light-guided surface engineering for biomedical applications. Bioconjug Chem 2008; 19:792-6. [PMID: 18314938 DOI: 10.1021/bc700406w] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Free radical species generated through fluorescence photobleaching have been reported to effectively couple a water-soluble species to surfaces containing electron-rich sites . In this report, we expand upon this strategy to control the patterned attachment of antibodies and peptides to surfaces for biosensing and tissue engineering applications. In the first application, we compare hydrophobic attachment and photobleaching methods to immobilize FITC-labeled anti-M13K07 bacteriophage antibodies to the SiO2 layer of a differential capacitive biosensor and to the polyester filament of a feedback-controlled filament array. On both surfaces, antibody attachment and function were superior to the previously employed hydrophobic attachment. Furthermore, a laser scanning confocal microscope could be used for automated, software-guided photoattachment chemistry. In a second application, the cell-adhesion peptide RGDS was site-specifically photocoupled to glass coated with fluorescein-conjugated poly(ethylene glycol). RGDS attachment and bioactivity were characterized by a fibroblast adhesion assay. Cell adhesion was limited to sites of RGDS photocoupling. These examples illustrate that fluorophore-based photopatterning can be achieved by both solution-phase fluorophores or surface-adhered fluorophores. The coupling preserves the bioactivity of the patterned species, is amenable to a variety of surfaces, and is readily accessible to laboratories with fluorescence imaging equipment. The flexibility offered by visible light patterning will likely have many useful applications in bioscreening and tissue engineering where the controlled placement of biomolecules and cells is critical, and should be considered as an alternative to chemical coupling methods.
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Affiliation(s)
- Ashwath Jayagopal
- Department of Biomedical Engineering, Vanderbilt University, 5932 Stevenson Center, Nashville, TN 37232, USA
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21
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Current awareness on yeast. Yeast 2007. [DOI: 10.1002/yea.1325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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