1
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Gökerküçük EB, Tramier M, Bertolin G. Protocol for quantifying LC3B FRET biosensor activity in living cells using a broad-to-sensitive data analysis pipeline. STAR Protoc 2024; 5:103181. [PMID: 39178110 DOI: 10.1016/j.xpro.2024.103181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 04/10/2024] [Accepted: 06/18/2024] [Indexed: 08/25/2024] Open
Abstract
Here, we present a protocol to comprehensively quantify autophagy initiation using the readout of the microtubule associated protein 1 light chain 3 beta (LC3B) Förster's resonance energy transfer (FRET) biosensor. We describe steps for cell seeding, transfection, FRET/FLIM (fluorescence lifetime imaging microscopy) imaging, and image analysis. This protocol can be useful in any physiology- or disease-related paradigm where the LC3B biosensor can be expressed to determine whether autophagy has been initiated or is stalled. The analysis pipeline presented here can be applied to any other genetically encoded FRET sensor imaged using FRET/FLIM. For complete details on the use and execution of this protocol, please refer to Gökerküçük et al.1.
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Affiliation(s)
- Elif Begüm Gökerküçük
- Univ Rennes, CNRS, IGDR (Institute of Genetics and Development of Rennes), UMR 6290, F-35000 Rennes, France
| | - Marc Tramier
- Univ Rennes, CNRS, IGDR (Institute of Genetics and Development of Rennes), UMR 6290, F-35000 Rennes, France.
| | - Giulia Bertolin
- Univ Rennes, CNRS, IGDR (Institute of Genetics and Development of Rennes), UMR 6290, F-35000 Rennes, France.
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2
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Pedre B. A guide to genetically-encoded redox biosensors: State of the art and opportunities. Arch Biochem Biophys 2024; 758:110067. [PMID: 38908743 DOI: 10.1016/j.abb.2024.110067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2024] [Revised: 06/18/2024] [Accepted: 06/19/2024] [Indexed: 06/24/2024]
Abstract
Genetically-encoded redox biosensors have become invaluable tools for monitoring cellular redox processes with high spatiotemporal resolution, coupling the presence of the redox-active analyte with a change in fluorescence signal that can be easily recorded. This review summarizes the available fluorescence recording methods and presents an in-depth classification of the redox biosensors, organized by the analytes they respond to. In addition to the fluorescent protein-based architectures, this review also describes the recent advances on fluorescent, chemigenetic-based redox biosensors and other emerging chemigenetic strategies. This review examines how these biosensors are designed, the biosensors sensing mechanism, and their practical advantages and disadvantages.
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Affiliation(s)
- Brandán Pedre
- Biochemistry, Molecular and Structural Biology Unit, Department of Chemistry, KU Leuven, Belgium.
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3
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Li Y, Zhang Y, Wang M, Su J, Dong X, Yang Y, Wang H, Li Q. The mammalian actin elongation factor ENAH/MENA contributes to autophagosome formation via its actin regulatory function. Autophagy 2024; 20:1798-1814. [PMID: 38705725 PMCID: PMC11262208 DOI: 10.1080/15548627.2024.2347105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 04/19/2024] [Indexed: 05/07/2024] Open
Abstract
Macroautophagy/autophagy is a catabolic process crucial for degrading cytosolic components and damaged organelles to maintain cellular homeostasis, enabling cells to survive in extreme extracellular environments. ENAH/MENA, a member of the Ena/VASP protein family, functions as a highly efficient actin elongation factor. In this study, our objective was to explore the role of ENAH in the autophagy process. Initially, we demonstrated that depleting ENAH in cancer cells inhibits autophagosome formation. Subsequently, we observed ENAH's colocalization with MAP1LC3/LC3 during tumor cell starvation, dependent on actin cytoskeleton polymerization and the interaction between ENAH and BECN1 (beclin 1). Additionally, mammalian ATG9A formed a ring-like structure around ENAH-LC3 puncta during starvation, relying on actin cytoskeleton polymerization. Furthermore, ENAH's EVH1 and EVH2 domains were found to be indispensable for its colocalization with LC3 and BECN1, while the PRD domain played a crucial role in the formation of the ATG9A ring. Finally, our study revealed ENAH-led actin comet tails in autophagosome trafficking. In conclusion, our findings provide initial insights into the regulatory role of the mammalian actin elongation factor ENAH in autophagy.Abbreviations: 3-MA 3-methyladenine; ABPs actin-binding proteins; ATG autophagy related; ATG9A autophagy related 9A; Baf A1 bafilomycin A1; CM complete medium; CytERM endoplasmic reticulum signal-anchor membrane protein; Cyto D cytochalasin D; EBSS Earl's balanced salt solution; ENAH/MENA ENAH actin regulator; EVH1 Ena/VASP homology 1 domain; EVH2 Ena/VASP homology 2 domain; GAPDH glyceraldehyde-3-phosphate dehydrogenase; Lat B latrunculin B; LC3-I unlipidated form of LC3; LC3-II phosphatidylethanolamine-conjugated form of LC3; MAP1LC3/LC3 microtubule associated protein 1 light chain 3; mEGFP monomeric enhanced green fluorescent protein; mTagBFP2 monomeric Tag blue fluorescent protein 2; OSER organized smooth endoplasmic reticulum; PRD proline-rich domain; PtdIns3K class III phosphatidylinositol 3-kinase; WM wortmannin.
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Affiliation(s)
- Yueheng Li
- Department of Pathology, School of Basic Medical Science, Fudan University, Shanghai, China
- Department of Pharmacology, School of Pharmacy, Fudan University, Shanghai, China
| | - Yafei Zhang
- Department of Pharmacology, School of Pharmacy, Fudan University, Shanghai, China
- Department of Infectious Diseases, The Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui province, China
| | - Menghui Wang
- Department of Pharmacology, School of Pharmacy, Fudan University, Shanghai, China
| | - Junhui Su
- Department of Pharmacology, School of Pharmacy, Fudan University, Shanghai, China
| | - Xinjue Dong
- Department of Pharmacology, School of Pharmacy, Fudan University, Shanghai, China
| | - Yuqi Yang
- Department of Pharmacology, School of Pharmacy, Fudan University, Shanghai, China
| | - Hongshan Wang
- Department of General Surgery, Zhongshan Hospital, Fudan University, Shanghai, P. R. China
| | - QingQuan Li
- Department of Pharmacology, School of Pharmacy, Fudan University, Shanghai, China
- Department of Infectious Diseases, The Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui province, China
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4
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Inal MA, Banzai K, Kamiyama R, Kamiyama D. Cell-type-specific Labeling of Endogenous Proteins Using the Split GFP System in Drosophila. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.06.592806. [PMID: 38826199 PMCID: PMC11140830 DOI: 10.1101/2024.05.06.592806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
i. Accurate identification of the locations of endogenous proteins is crucial for understanding their functions in tissues and cells. However, achieving precise cell-type-specific labeling of proteins has been challenging in vivo . A notable solution to this challenge is the self-complementing split green fluorescent protein (GFP 1-10/11 ) system. In this paper, we present a detailed protocol for labeling endogenous proteins in a cell-type-specific manner using the GFP 1-10/11 system in fruit flies. This approach depends on the reconstitution of the GFP 1-10 and GFP 11 fragments, creating a fluorescence signal. We insert the GFP 11 fragment into a specific genomic locus while expressing its counterpart, GFP 1-10 , through an available Gal4 driver line. The unique aspect of this system is that neither GFP 1-10 nor GFP 11 alone emits fluorescence, enabling the precise detection of protein localization only in Gal4-positive cells expressing the GFP 11 tagged endogenous protein. We illustrate this technique using the adhesion molecule gene teneurin-m ( Ten-m ) as a model, highlighting the generation and validation of GFP 11 protein trap lines via Minos-mediated integration cassette (MiMIC) insertion. Furthermore, we demonstrate the cell-type-specific labeling of Ten-m proteins in the larval brains of fruit flies. This method significantly enhances our ability to image endogenous protein localization patterns in a cell-type-specific manner and is adaptable to various model organisms beyond fruit flies.
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5
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Shweta H, Gupta K, Zhou Y, Cui X, Li S, Lu Z, Goldman YE, Dantzig JA. Characterization and structural basis for the brightness of mCLIFY: a novel monomeric and circularly permuted bright yellow fluorescent protein. RESEARCH SQUARE 2024:rs.3.rs-4638282. [PMID: 39070629 PMCID: PMC11276004 DOI: 10.21203/rs.3.rs-4638282/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
We present mCLIFY: a monomeric, bright, yellow, and long-lived fluorescent protein (FP) created by circular permutation of YPet, the brightest yellow FP from Aequorea Victoria for use in cellular and in vitro single molecule studies. mCLIFY retains the enhanced photophysical properties of YPET as a monomer at concentrations ≤ 40 μM. In contrast, we determined that YPet has a dimerization dissociation constant (K D 1-2) of 3.4 μM. Dimerization of YPet can cause homo-FRET, which underlies quantitative errors due to dimerization and homo-FRET. We determined the atomic structure of mCLIFY at 1.57 Å resolution and used its similarity with Venus for guided chromophore-targeted substitution studies to provide insights into its enhanced photophysical properties. The mutation V58L within the chromophore pocket improved quantum yield and extinction coefficient, making mCLIFY ~30% brighter than Venus. The extensive characterization of the photophysical and structural properties of YPet and mCLIFY presented here allowed us to reveal the basis of their long lifetimes and enhanced brightness and the basis of YPet's dimerization.
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Affiliation(s)
- Him Shweta
- Pennsylvania Muscle Institute, University of Pennsylvania, Philadelphia, PA-19104, United States of America
- Center for Engineering Mechanobiology (CEMB), Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA-19104, United States of America
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA-19104, United States of America
- Present address: Departments of Pharmacology and Cellular and Molecular Biology, University of California, Davis, CA-95616
| | - Kushol Gupta
- Department of Biochemistry & Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA-19104, United States of America
| | - Yufeng Zhou
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA-19104, United States of America
| | - Xiaonan Cui
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA-19104, United States of America
| | - Selene Li
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA-19104, United States of America
| | - Zhe Lu
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA-19104, United States of America
| | - Yale E. Goldman
- Pennsylvania Muscle Institute, University of Pennsylvania, Philadelphia, PA-19104, United States of America
- Center for Engineering Mechanobiology (CEMB), Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA-19104, United States of America
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA-19104, United States of America
- Present address: Departments of Pharmacology and Cellular and Molecular Biology, University of California, Davis, CA-95616
| | - Jody A. Dantzig
- Pennsylvania Muscle Institute, University of Pennsylvania, Philadelphia, PA-19104, United States of America
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA-19104, United States of America
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6
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Son JB, Kim S, Yang S, Ahn Y, Lee NK. Analysis of Fluorescent Proteins for Observing Single Gene Locus in a Live and Fixed Escherichia coli Cell. J Phys Chem B 2024; 128:6730-6741. [PMID: 38968413 PMCID: PMC11264270 DOI: 10.1021/acs.jpcb.4c01816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Revised: 06/21/2024] [Accepted: 06/27/2024] [Indexed: 07/07/2024]
Abstract
Fluorescent proteins (FPs) are essential tools for advanced microscopy techniques such as super-resolution imaging, single-particle tracking, and quantitative single-molecule counting. Various FPs fused to DNA-binding proteins have been used to observe the subcellular location and movement of specific gene loci in living and fixed bacterial cells. However, quantitative assessments of the properties of FPs for gene locus measurements are still lacking. Here, we assessed various FPs to observe specific gene loci in live and fixed Escherichia coli cells using a fluorescent repressor-operator binding system (FROS), tet operator-Tet repressor proteins (TetR). Tsr-fused FPs were used to assess the intensity and photostability of various FPs (five red FPs: mCherry2, FusionRed, mRFP, mCrimson3, and dKatushka; and seven yellow FPs: SYFP2, Venus, mCitrine, YPet, mClover3, mTopaz, and EYFP) at the single-molecule level in living cells. These FPs were then used for gene locus measurements using FROS. Our results indicate that TetR-mCrimson3 (red) and TetR-EYFP (yellow) had better properties for visualizing gene loci than the other TetR-FPs. Furthermore, fixation procedures affected the clustering of diffusing TetR-FPs and altered the locations of the TetR-FP foci. Fixation with formaldehyde consistently disrupted proper DNA locus observations using TetR-FPs. Notably, the foci measured using TetR-mCrimson3 remained close to their original positions in live cells after glyoxal fixation. This in vivo study provides a cell-imaging guide for the use of FPs for gene-locus observation in E. coli and a scheme for evaluating the use of FPs for other cell-imaging purposes.
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Affiliation(s)
| | | | | | - Youmin Ahn
- Department of Chemistry, Seoul
National University, 08826 Seoul, South
Korea
| | - Nam Ki Lee
- Department of Chemistry, Seoul
National University, 08826 Seoul, South
Korea
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7
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Barkley RJR, Crowley JC, Brodrick AJ, Zipfel WR, Parker JSL. Fluorescent protein tags affect the condensation properties of a phase-separating viral protein. Mol Biol Cell 2024; 35:ar100. [PMID: 38809580 PMCID: PMC11244164 DOI: 10.1091/mbc.e24-01-0013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 05/17/2024] [Accepted: 05/24/2024] [Indexed: 05/30/2024] Open
Abstract
Fluorescent protein (FP) tags are extensively used to visualize and characterize the properties of biomolecular condensates despite a lack of investigation into the effects of these tags on phase separation. Here, we characterized the dynamic properties of µNS, a viral protein hypothesized to undergo phase separation and the main component of mammalian orthoreovirus viral factories. Our interest in the sequence determinants and nucleation process of µNS phase separation led us to compare the size and density of condensates formed by FP::µNS to the untagged protein. We found an FP-dependent increase in droplet size and density, which suggests that FP tags can promote µNS condensation. To further assess the effect of FP tags on µNS droplet formation, we fused FP tags to µNS mutants to show that the tags could variably induce phase separation of otherwise noncondensing proteins. By comparing fluorescent constructs with untagged µNS, we identified mNeonGreen as the least artifactual FP tag that minimally perturbed µNS condensation. These results show that FP tags can promote phase separation and that some tags are more suitable for visualizing and characterizing biomolecular condensates with minimal experimental artifacts.
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Affiliation(s)
- Russell J. R. Barkley
- Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14850
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, NY 14850
| | - Jack C. Crowley
- School of Applied and Engineering Physics, College of Engineering, Cornell University, Ithaca, NY 14850
| | - Andrew J. Brodrick
- Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14850
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, NY 14850
| | - Warren R. Zipfel
- School of Applied and Engineering Physics, College of Engineering, Cornell University, Ithaca, NY 14850
- Meinig School of Biomedical Engineering, College of Engineering, Cornell University, Ithaca, NY 14850
| | - John S. L. Parker
- Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14850
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, NY 14850
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8
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Ajiki M, Yoshikawa M, Miyazaki T, Kawasaki A, Aoki K, Nakatsu F, Tsukiji S. ORP9-PH domain-based fluorescent reporters for visualizing phosphatidylinositol 4-phosphate dynamics in living cells. RSC Chem Biol 2024; 5:544-555. [PMID: 38846081 PMCID: PMC11151866 DOI: 10.1039/d3cb00232b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Accepted: 04/15/2024] [Indexed: 06/09/2024] Open
Abstract
Fluorescent reporters that visualize phosphatidylinositol 4-phosphate (PI4P) in living cells are indispensable to elucidate the roles of this fundamental lipid in cell physiology. However, currently available PI4P reporters have limitations, such as Golgi-biased localization and low detection sensitivity. Here, we present a series of fluorescent PI4P reporters based on the pleckstrin homology (PH) domain of oxysterol-binding protein-related protein 9 (ORP9). We show that the green fluorescent protein AcGFP1-tagged ORP9-PH domain can be used as a fluorescent PI4P reporter to detect cellular PI4P across its wide distribution at multiple cellular locations, including the plasma membrane (PM), Golgi, endosomes, and lysosomes with high specificity and contrast. We also developed blue, red, and near-infrared fluorescent PI4P reporters suitable for multicolor fluorescence imaging experiments. Finally, we demonstrate the utility of the ORP9-PH domain-based reporter to visualize dynamic changes in the PI4P distribution and level in living cells upon synthetic ER-PM membrane contact manipulation and GPCR stimulation. This work offers a new set of genetically encoded fluorescent PI4P reporters that are practically useful for the study of PI4P biology.
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Affiliation(s)
- Moeka Ajiki
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology Gokiso-cho, Showa-ku Nagoya 466-8555 Japan
| | - Masaru Yoshikawa
- Department of Nanopharmaceutical Sciences, Nagoya Institute of Technology Gokiso-cho, Showa-ku Nagoya 466-8555 Japan
| | - Tomoki Miyazaki
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology Gokiso-cho, Showa-ku Nagoya 466-8555 Japan
| | - Asami Kawasaki
- Department of Neurochemistry and Molecular Cell Biology, Graduate School of Medical and Dental Sciences, Niigata University 1-757 Asahimachi, Chuo-ku Niigata 951-8510 Japan
| | - Kazuhiro Aoki
- Quantitative Biology Research Group, Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences 5-1 Higashiyama, Myodaiji-cho Okazaki Aichi 444-8787 Japan
- Division of Quantitative Biology, National Institute for Basic Biology, National Institutes of Natural Sciences 5-1 Higashiyama, Myodaiji-cho Okazaki Aichi 444-8787 Japan
- Department of Basic Biology, Faculty of Life Science, SOKENDAI (The Graduate University for Advanced Studies) 5-1 Higashiyama, Myodaiji-cho Okazaki Aichi 444-8787 Japan
| | - Fubito Nakatsu
- Department of Neurochemistry and Molecular Cell Biology, Graduate School of Medical and Dental Sciences, Niigata University 1-757 Asahimachi, Chuo-ku Niigata 951-8510 Japan
| | - Shinya Tsukiji
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology Gokiso-cho, Showa-ku Nagoya 466-8555 Japan
- Department of Nanopharmaceutical Sciences, Nagoya Institute of Technology Gokiso-cho, Showa-ku Nagoya 466-8555 Japan
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9
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Štrancar U, D’Ercole C, Cikatricisová L, Nakić M, De March M, de Marco A. A Practical Guide for the Quality Evaluation of Fluobodies/Chromobodies. Biomolecules 2024; 14:587. [PMID: 38785994 PMCID: PMC11117837 DOI: 10.3390/biom14050587] [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: 04/09/2024] [Revised: 05/07/2024] [Accepted: 05/14/2024] [Indexed: 05/25/2024] Open
Abstract
BACKGROUND Fluorescent proteins (FPs) are pivotal reagents for flow cytometry analysis or fluorescent microscopy. A new generation of immunoreagents (fluobodies/chromobodies) has been developed by fusing recombinant nanobodies to FPs. METHODS We analyzed the quality of such biomolecules by a combination of gel filtration and SDS-PAGE to identify artefacts due to aggregation or material degradation. RESULTS In the SDS-PAGE run, unexpected bands corresponding to separate fluobodies were evidenced and characterized as either degradation products or artefacts that systematically resulted in the presence of specific FPs and some experimental conditions. The elimination of N-terminal methionine from FPs did not impair the appearance of FP fragments, whereas the stability and migration characteristics of some FP constructs were strongly affected by heating in loading buffer, which is a step samples undergo before electrophoretic separation. CONCLUSIONS In this work, we provide explanations for some odd results observed during the quality control of fluobodies and summarize practical suggestions for the choice of the most convenient FPs to fuse to antibody fragments.
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Affiliation(s)
| | | | | | | | | | - Ario de Marco
- Laboratory of Environmental and Life Sciences, University of Nova Gorica, Vipavska cesta 13, Rožna Dolina, 5000 Nova Gorica, Slovenia; (U.Š.); (C.D.); (L.C.); (M.N.); (M.D.M.)
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10
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Kasprzycka W, Szumigraj W, Wachulak P, Trafny EA. New approaches for low phototoxicity imaging of living cells and tissues. Bioessays 2024; 46:e2300122. [PMID: 38514402 DOI: 10.1002/bies.202300122] [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: 07/04/2023] [Revised: 03/06/2024] [Accepted: 03/07/2024] [Indexed: 03/23/2024]
Abstract
Fluorescence microscopy is a powerful tool used in scientific and medical research, but it is inextricably linked to phototoxicity. Neglecting phototoxicity can lead to erroneous or inconclusive results. Recently, several reports have addressed this issue, but it is still underestimated by many researchers, even though it can lead to cell death. Phototoxicity can be reduced by appropriate microscopic techniques and carefully designed experiments. This review focuses on recent strategies to reduce phototoxicity in microscopic imaging of living cells and tissues. We describe digital image processing and new hardware solutions. We point out new modifications of microscopy methods and hope that this review will interest microscopy hardware engineers. Our aim is to underscore the challenges and potential solutions integral to the design of microscopy systems. Simultaneously, we intend to engage biologists, offering insight into the latest technological advancements in imaging that can enhance their understanding and practice.
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Affiliation(s)
- Wiktoria Kasprzycka
- Biomedical Engineering Centre, Institute of Optoelectronics, Military University of Technology, Kaliskiego, Warsaw, Poland
| | - Wiktoria Szumigraj
- Biomedical Engineering Centre, Institute of Optoelectronics, Military University of Technology, Kaliskiego, Warsaw, Poland
| | - Przemysław Wachulak
- Laser Technology Division, Institute of Optoelectronics, Military University of Technology, Kaliskiego, Warsaw, Poland
| | - Elżbieta Anna Trafny
- Biomedical Engineering Centre, Institute of Optoelectronics, Military University of Technology, Kaliskiego, Warsaw, Poland
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11
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Wang Z, Chen C, Ge X. Large T antigen mediated target gene replication improves site-specific recombination efficiency. Front Bioeng Biotechnol 2024; 12:1377167. [PMID: 38737535 PMCID: PMC11082406 DOI: 10.3389/fbioe.2024.1377167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Accepted: 04/11/2024] [Indexed: 05/14/2024] Open
Abstract
With advantages of high-fidelity, monoclonality and large cargo capacity, site-specific recombination (SSR) holds great promises for precise genomic modifications. However, broad applications of SSR have been hurdled by low integration efficiency, and the amount of donor DNA available in nucleus for SSR presents as a limiting factor. Inspired by the DNA replication mechanisms observed in double-stranded DNA virus SV40, we hypothesized that expression of SV40 large T antigen (TAg) can increase the copy number of the donor plasmid bearing an SV40 origin, and in consequence promote recombination events. This hypothesis was tested with dual recombinase-mediated cassette exchange (RMCE) in suspension 293F cells. Results showed that TAg co-transfection significantly enhanced SSR in polyclonal cells. In the monoclonal cell line carrying a single landing pad at an identified genomic locus, 12% RMCE efficiency was achieved, and such improvement was indeed correlated with donor plasmid amplification. The developed TAg facilitated RMCE (T-RMCE) was exploited for the construction of large libraries of >107 diversity, from which GFP variants with enhanced fluorescence were isolated. We expect the underlying principle of target gene amplification can be applicable to other SSR processes and gene editing approaches in general for directed evolution and large-scale genomic screening in mammalian cells.
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Affiliation(s)
- Zening Wang
- Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX, United States
- Department of Chemical and Environmental Engineering, University of California Riverside, Riverside, CA, United States
| | - Chuan Chen
- Department of Chemical and Environmental Engineering, University of California Riverside, Riverside, CA, United States
| | - Xin Ge
- Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX, United States
- Department of Chemical and Environmental Engineering, University of California Riverside, Riverside, CA, United States
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12
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Perez D, Dowlatshahi DP, Azaldegui CA, Dahlberg PD, Moerner WE. Exploring transient states of PAmKate to enable improved cryogenic single-molecule imaging. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.24.590965. [PMID: 38712218 PMCID: PMC11071506 DOI: 10.1101/2024.04.24.590965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Super-resolved cryogenic correlative light and electron microscopy is a powerful approach which combines the single-molecule specificity and sensitivity of fluorescence imaging with the nano-scale resolution of cryogenic electron tomography. Key to this method is active control over the emissive state of fluorescent labels to ensure sufficient sparsity to localize individual emitters. Recent work has identified fluorescent proteins (FPs) which photoactivate or photoswitch efficiently at cryogenic temperatures, but long on-times due to reduced quantum yield of photobleaching remains a challenge for imaging structures with a high density of localizations. In this work, we explore the photophysical properties of the red photoactivatable FP PAmKate and identify a 2-color process leading to enhanced turn-off of active emitters, improving localization rate. Specifically, after excitation of ground state molecules, we find a transient state forms with a lifetime of ~2 ms which can be bleached by exposure to a second wavelength. We measure the response of the transient state to different wavelengths, demonstrate how this mechanism can be used to improve imaging, and provide a blueprint for study of other FPs at cryogenic temperatures.
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Affiliation(s)
- Davis Perez
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Dara P Dowlatshahi
- Biosciences Division, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
- Department of Structural Biology, Stanford University, Stanford, California 94305, United States
| | - Christopher A Azaldegui
- Division of CryoEM and Bioimaging, Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Peter D Dahlberg
- Division of CryoEM and Bioimaging, Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - W E Moerner
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
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13
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Delgadillo-Guevara M, Halte M, Erhardt M, Popp PF. Fluorescent tools for the standardized work in Gram-negative bacteria. J Biol Eng 2024; 18:25. [PMID: 38589953 PMCID: PMC11003136 DOI: 10.1186/s13036-024-00420-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2024] [Accepted: 03/18/2024] [Indexed: 04/10/2024] Open
Abstract
Standardized and thoroughly characterized genetic tools are a prerequisite for studying cellular processes to ensure the reusability and consistency of experimental results. The discovery of fluorescent proteins (FPs) represents a milestone in the development of genetic reporters for monitoring transcription or protein localization in vivo. FPs have revolutionized our understanding of cellular dynamics by enabling the real-time visualization and tracking of biological processes. Despite these advancements, challenges remain in the appropriate use of FPs, specifically regarding their proper application, protein turnover dynamics, and the undesired disruption of cellular functions. Here, we systematically compared a comprehensive set of 15 FPs and assessed their performance in vivo by focusing on key parameters, such as signal over background ratios and protein stability rates, using the Gram-negative model organism Salmonella enterica as a representative host. We evaluated four protein degradation tags in both plasmid- and genome-based systems and our findings highlight the necessity of introducing degradation tags to analyze time-sensitive cellular processes. We demonstrate that the gain of dynamics mediated by the addition of degradation tags impacts the cell-to-cell heterogeneity of plasmid-based but not genome-based reporters. Finally, we probe the applicability of FPs for protein localization studies in living cells using standard and super-resolution fluorescence microscopy. In summary, our study underscores the importance of careful FP selection and paves the way for the development of improved genetic reporters to enhance the reproducibility and reliability of fluorescence-based research in Gram-negative bacteria and beyond.
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Affiliation(s)
- Mario Delgadillo-Guevara
- Institute of Biology/Molecular Microbiology, Humboldt-Universität zu Berlin, Berlin, 10115, Germany
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC, Australia
| | - Manuel Halte
- Institute of Biology/Molecular Microbiology, Humboldt-Universität zu Berlin, Berlin, 10115, Germany
| | - Marc Erhardt
- Institute of Biology/Molecular Microbiology, Humboldt-Universität zu Berlin, Berlin, 10115, Germany
- Max Planck Unit for the Science of Pathogens, Berlin, 10117, Germany
| | - Philipp F Popp
- Institute of Biology/Molecular Microbiology, Humboldt-Universität zu Berlin, Berlin, 10115, Germany.
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14
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Agranier E, Crétin P, Joublin-Delavat A, Veillard L, Touahri K, Delavat F. Development and utilization of new O 2-independent bioreporters. Microbiol Spectr 2024; 12:e0409123. [PMID: 38441526 PMCID: PMC10986488 DOI: 10.1128/spectrum.04091-23] [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: 12/01/2023] [Accepted: 02/19/2024] [Indexed: 04/06/2024] Open
Abstract
Fluorescent proteins have revolutionized science since their discovery in 1962. They have enabled imaging experiments to decipher the function of proteins, cells, and organisms, as well as gene regulation. Green fluorescent protein and all its derivatives are now standard tools in cell biology, immunology, molecular biology, and microbiology laboratories around the world. A common feature of these proteins is their dioxygen (O2)-dependent maturation allowing fluorescence, which precludes their use in anoxic contexts. In this work, we report the development and in cellulo characterization of genetic circuits encoding the O2-independent KOFP-7 protein, a flavin-binding fluorescent protein. We have optimized the genetic circuit for high bacterial fluorescence at population and single-cell level, implemented this circuit in various plasmids differing in host range, and quantified their fluorescence under both aerobic and anaerobic conditions. Finally, we showed that KOFP-7-based constructions can be used to produce fluorescing cells of Vibrio diazotrophicus, a facultative anaerobe, demonstrating the usefulness of the genetic circuits for various anaerobic bacteria. These genetic circuits can thus be modified at will, both to solve basic and applied research questions, opening a highway to shed light on the obscure anaerobic world.IMPORTANCEFluorescent proteins are used for decades, and have allowed major discoveries in biology in a wide variety of fields, and are used in environmental as well as clinical contexts. Green fluorescent protein (GFP) and all its derivatives share a common feature: they rely on the presence of dioxygen (O2) for protein maturation and fluorescence. This dependency precludes their use in anoxic environments. Here, we constructed a series of genetic circuits allowing production of KOFP-7, an O2-independant flavin-binding fluorescent protein. We demonstrated that Escherichia coli cells producing KOFP-7 are fluorescent, both at the population and single-cell levels. Importantly, we showed that, unlike cells producing GFP, cells producing KOFP-7 are fluorescent in anoxia. Finally, we demonstrated that Vibrio diazotrophicus NS1, a facultative anaerobe, is fluorescent in the absence of O2 when KOFP-7 is produced. Altogether, the development of new genetic circuits allowing O2-independent fluorescence will open new perspective to study anaerobic processes.
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Affiliation(s)
- Eva Agranier
- Nantes Université, CNRS, US2B, UMR6286, Nantes, France
| | | | | | - Léa Veillard
- Nantes Université, CNRS, US2B, UMR6286, Nantes, France
| | - Katia Touahri
- Nantes Université, CNRS, US2B, UMR6286, Nantes, France
- Laboratoire Chimie et Biochimie de Molécules Bioactives, Université de Strasbourg/CNRS, UMR7177, Strasbourg, France
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15
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Zhang H, Lesnov GD, Subach OM, Zhang W, Kuzmicheva TP, Vlaskina AV, Samygina VR, Chen L, Ye X, Nikolaeva AY, Gabdulkhakov A, Papadaki S, Qin W, Borshchevskiy V, Perfilov MM, Gavrikov AS, Drobizhev M, Mishin AS, Piatkevich KD, Subach FV. Bright and stable monomeric green fluorescent protein derived from StayGold. Nat Methods 2024; 21:657-665. [PMID: 38409224 DOI: 10.1038/s41592-024-02203-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 01/31/2024] [Indexed: 02/28/2024]
Abstract
The high brightness and photostability of the green fluorescent protein StayGold make it a particularly attractive probe for long-term live-cell imaging; however, its dimeric nature precludes its application as a fluorescent tag for some proteins. Here, we report the development and crystal structures of a monomeric variant of StayGold, named mBaoJin, which preserves the beneficial properties of its precursor, while serving as a tag for structural proteins and membranes. Systematic benchmarking of mBaoJin against popular green fluorescent proteins and other recently introduced monomeric and pseudomonomeric derivatives of StayGold established mBaoJin as a bright and photostable fluorescent protein, exhibiting rapid maturation and high pH/chemical stability. mBaoJin was also demonstrated for super-resolution, long-term live-cell imaging and expansion microscopy. We further showed the applicability of mBaoJin for neuronal labeling in model organisms, including Caenorhabditis elegans and mice.
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Affiliation(s)
- Hanbin Zhang
- School of Life Sciences, Westlake University, Hangzhou, China
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, China
| | - Gleb D Lesnov
- Complex of NBICS Technologies, National Research Center 'Kurchatov Institute', Moscow, Russia
| | - Oksana M Subach
- Complex of NBICS Technologies, National Research Center 'Kurchatov Institute', Moscow, Russia
| | - Wenhao Zhang
- School of Life Sciences, Westlake University, Hangzhou, China
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, China
| | - Tatyana P Kuzmicheva
- Complex of NBICS Technologies, National Research Center 'Kurchatov Institute', Moscow, Russia
| | - Anna V Vlaskina
- Complex of NBICS Technologies, National Research Center 'Kurchatov Institute', Moscow, Russia
| | - Valeriya R Samygina
- Complex of NBICS Technologies, National Research Center 'Kurchatov Institute', Moscow, Russia
- Institute of Crystallography of Federal Research Scientific Center 'Crystallography and Photonics' of the Russian Academy of Sciences, Moscow, Russia
| | - Liangyi Chen
- Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, China
- PKU-IDG/McGovern Institute for Brain Research, Beijing, China
| | - Xianxin Ye
- Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, China
| | - Alena Yu Nikolaeva
- Complex of NBICS Technologies, National Research Center 'Kurchatov Institute', Moscow, Russia
| | - Azat Gabdulkhakov
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Russia
| | - Stavrini Papadaki
- School of Life Sciences, Westlake University, Hangzhou, China
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, China
| | - Wenming Qin
- National Facility for Protein Science in Shanghai, Shanghai Advanced Research Institute CAS, Shanghai, China
| | | | - Maxim M Perfilov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Alexey S Gavrikov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Mikhail Drobizhev
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, USA
| | - Alexander S Mishin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Kiryl D Piatkevich
- School of Life Sciences, Westlake University, Hangzhou, China.
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, China.
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, China.
| | - Fedor V Subach
- Complex of NBICS Technologies, National Research Center 'Kurchatov Institute', Moscow, Russia.
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16
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Tomris I, van der Woude R, de Paiva Froes Rocha R, Torrents de la Peña A, Ward AB, de Vries RP. Viral envelope proteins fused to multiple distinct fluorescent reporters to probe receptor binding. Protein Sci 2024; 33:e4974. [PMID: 38533540 DOI: 10.1002/pro.4974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 03/04/2024] [Accepted: 03/13/2024] [Indexed: 03/28/2024]
Abstract
Enveloped viruses carry one or multiple proteins with receptor-binding functionalities. Functional receptors can be glycans, proteinaceous, or both; therefore, recombinant protein approaches are instrumental in attaining new insights regarding viral envelope protein receptor-binding properties. Visualizing and measuring receptor binding typically entails antibody detection or direct labeling, whereas direct fluorescent fusions are attractive tools in molecular biology. Here, we report a suite of distinct fluorescent fusions, both N- and C-terminal, for influenza A virus hemagglutinins and SARS-CoV-2 spike RBD. The proteins contained three or six fluorescent protein barrels and were applied directly to cells to assess receptor binding properties.
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Affiliation(s)
- Ilhan Tomris
- Department of Chemical Biology & Drug Discovery, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, The Netherlands
| | - Roosmarijn van der Woude
- Department of Chemical Biology & Drug Discovery, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, The Netherlands
| | - Rebeca de Paiva Froes Rocha
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, USA
| | - Alba Torrents de la Peña
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, USA
| | - Andrew B Ward
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, USA
| | - Robert P de Vries
- Department of Chemical Biology & Drug Discovery, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, The Netherlands
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17
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Nikolaev A, Kuzmin A, Markeeva E, Kuznetsova E, Ryzhykau YL, Semenov O, Anuchina A, Remeeva A, Gushchin I. Reengineering of a flavin-binding fluorescent protein using ProteinMPNN. Protein Sci 2024; 33:e4958. [PMID: 38501498 PMCID: PMC10949330 DOI: 10.1002/pro.4958] [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: 09/05/2023] [Revised: 01/12/2024] [Accepted: 02/18/2024] [Indexed: 03/20/2024]
Abstract
Recent advances in machine learning techniques have led to development of a number of protein design and engineering approaches. One of them, ProteinMPNN, predicts an amino acid sequence that would fold and match user-defined backbone structure. Its performance was previously tested for proteins composed of standard amino acids, as well as for peptide- and protein-binding proteins. In this short report, we test whether ProteinMPNN can be used to reengineer a non-proteinaceous ligand-binding protein, flavin-based fluorescent protein CagFbFP. We fixed the native backbone conformation and the identity of 20 amino acids interacting with the chromophore (flavin mononucleotide, FMN) while letting ProteinMPNN predict the rest of the sequence. The software package suggested replacing 36-48 out of the remaining 86 amino acids so that the resulting sequences are 55%-66% identical to the original one. The three designs that we tested experimentally displayed different expression levels, yet all were able to bind FMN and displayed fluorescence, thermal stability, and other properties similar to those of CagFbFP. Our results demonstrate that ProteinMPNN can be used to generate diverging unnatural variants of fluorescent proteins, and, more generally, to reengineer proteins without losing their ligand-binding capabilities.
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Affiliation(s)
- Andrey Nikolaev
- Research Center for Molecular Mechanisms of Aging and Age‐Related DiseasesMoscow Institute of Physics and TechnologyDolgoprudnyRussia
| | - Alexander Kuzmin
- Research Center for Molecular Mechanisms of Aging and Age‐Related DiseasesMoscow Institute of Physics and TechnologyDolgoprudnyRussia
| | - Elena Markeeva
- Research Center for Molecular Mechanisms of Aging and Age‐Related DiseasesMoscow Institute of Physics and TechnologyDolgoprudnyRussia
| | - Elizaveta Kuznetsova
- Research Center for Molecular Mechanisms of Aging and Age‐Related DiseasesMoscow Institute of Physics and TechnologyDolgoprudnyRussia
| | - Yury L. Ryzhykau
- Research Center for Molecular Mechanisms of Aging and Age‐Related DiseasesMoscow Institute of Physics and TechnologyDolgoprudnyRussia
- Frank Laboratory of Neutron PhysicsJoint Institute for Nuclear ResearchDubnaRussia
| | - Oleg Semenov
- Research Center for Molecular Mechanisms of Aging and Age‐Related DiseasesMoscow Institute of Physics and TechnologyDolgoprudnyRussia
| | - Arina Anuchina
- Research Center for Molecular Mechanisms of Aging and Age‐Related DiseasesMoscow Institute of Physics and TechnologyDolgoprudnyRussia
| | - Alina Remeeva
- Research Center for Molecular Mechanisms of Aging and Age‐Related DiseasesMoscow Institute of Physics and TechnologyDolgoprudnyRussia
| | - Ivan Gushchin
- Research Center for Molecular Mechanisms of Aging and Age‐Related DiseasesMoscow Institute of Physics and TechnologyDolgoprudnyRussia
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18
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Ando R, Shimozono S, Ago H, Takagi M, Sugiyama M, Kurokawa H, Hirano M, Niino Y, Ueno G, Ishidate F, Fujiwara T, Okada Y, Yamamoto M, Miyawaki A. StayGold variants for molecular fusion and membrane-targeting applications. Nat Methods 2024; 21:648-656. [PMID: 38036853 PMCID: PMC11009113 DOI: 10.1038/s41592-023-02085-6] [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: 05/16/2023] [Accepted: 10/12/2023] [Indexed: 12/02/2023]
Abstract
Although StayGold is a bright and highly photostable fluorescent protein, its propensity for obligate dimer formation may hinder applications in molecular fusion and membrane targeting. To attain monovalent as well as bright and photostable labeling, we engineered tandem dimers of StayGold to promote dispersibility. On the basis of the crystal structure of this fluorescent protein, we disrupted the dimerization to generate a monomeric variant that offers improved photostability and brightness compared to StayGold. We applied the new monovalent StayGold tools to live-cell imaging experiments using spinning-disk laser-scanning confocal microscopy or structured illumination microscopy. We achieved cell-wide, high-spatiotemporal resolution and sustained imaging of dynamic subcellular events, including the targeting of endogenous condensin I to mitotic chromosomes, the movement of the Golgi apparatus and its membranous derivatives along microtubule networks, the distribution of cortical filamentous actin and the remolding of cristae membranes within mobile mitochondria.
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Affiliation(s)
- Ryoko Ando
- Laboratory for Cell Function Dynamics, RIKEN Center for Brain Science, Wako-city, Japan
- Biotechnological Optics Research Team, RIKEN Center for Advanced Photonics, Wako-city, Japan
- Department of Optical Biomedical Science, Institute for Life and Medical Sciences, Kyoto University, Kyoto, Japan
| | - Satoshi Shimozono
- Laboratory for Cell Function Dynamics, RIKEN Center for Brain Science, Wako-city, Japan
| | - Hideo Ago
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Japan
| | - Masatoshi Takagi
- Cellular Dynamics Laboratory, RIKEN Cluster for Pioneering Research (CPR), Saitama, Japan
| | - Mayu Sugiyama
- Laboratory for Cell Function Dynamics, RIKEN Center for Brain Science, Wako-city, Japan
| | - Hiroshi Kurokawa
- Laboratory for Cell Function Dynamics, RIKEN Center for Brain Science, Wako-city, Japan
| | - Masahiko Hirano
- Biotechnological Optics Research Team, RIKEN Center for Advanced Photonics, Wako-city, Japan
| | - Yusuke Niino
- Laboratory for Cell Function Dynamics, RIKEN Center for Brain Science, Wako-city, Japan
| | - Go Ueno
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Japan
| | - Fumiyoshi Ishidate
- Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Takahiro Fujiwara
- Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Yasushi Okada
- Laboratory for Cell Polarity Regulation, RIKEN Center for Biosystems Dynamics Research, Suita, Japan
- Department of Cell Biology, Department of Physics, UBI and WPI-IRCN, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Masaki Yamamoto
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Japan
| | - Atsushi Miyawaki
- Laboratory for Cell Function Dynamics, RIKEN Center for Brain Science, Wako-city, Japan.
- Biotechnological Optics Research Team, RIKEN Center for Advanced Photonics, Wako-city, Japan.
- Laboratory of Bioresponse Analysis, Institute for Life and Medical Sciences, Kyoto University, Kyoto, Japan.
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19
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Gelman S, Johnson B, Freschlin C, D'Costa S, Gitter A, Romero PA. Biophysics-based protein language models for protein engineering. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.15.585128. [PMID: 38559182 PMCID: PMC10980077 DOI: 10.1101/2024.03.15.585128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Protein language models trained on evolutionary data have emerged as powerful tools for predictive problems involving protein sequence, structure, and function. However, these models overlook decades of research into biophysical factors governing protein function. We propose Mutational Effect Transfer Learning (METL), a protein language model framework that unites advanced machine learning and biophysical modeling. Using the METL framework, we pretrain transformer-based neural networks on biophysical simulation data to capture fundamental relationships between protein sequence, structure, and energetics. We finetune METL on experimental sequence-function data to harness these biophysical signals and apply them when predicting protein properties like thermostability, catalytic activity, and fluorescence. METL excels in challenging protein engineering tasks like generalizing from small training sets and position extrapolation, although existing methods that train on evolutionary signals remain powerful for many types of experimental assays. We demonstrate METL's ability to design functional green fluorescent protein variants when trained on only 64 examples, showcasing the potential of biophysics-based protein language models for protein engineering.
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Affiliation(s)
- Sam Gelman
- Department of Computer Sciences, University of Wisconsin-Madison
- Morgridge Institute for Research
| | - Bryce Johnson
- Department of Computer Sciences, University of Wisconsin-Madison
- Morgridge Institute for Research
| | | | - Sameer D'Costa
- Department of Biochemistry, University of Wisconsin-Madison
| | - Anthony Gitter
- Department of Computer Sciences, University of Wisconsin-Madison
- Morgridge Institute for Research
- Department of Biostatistics and Medical Informatics, University of Wisconsin-Madison
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20
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Pham TG, Wu J. Recent advances in methods for live-cell RNA imaging. NANOSCALE 2024; 16:5537-5545. [PMID: 38414383 DOI: 10.1039/d4nr00129j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/29/2024]
Abstract
As one of the most fundamental building blocks of life, RNA plays critical roles in diverse biological processes, from X chromosome inactivation, genome stability maintenance, to embryo development. Being able to visualize the localization and dynamics of RNA can provide critical insights into these fundamental processes. In this review, we provide an overview of current methods for live-cell RNA imaging with a focus on methods for visualizing RNA in living mammalian cells with single-molecule resolution.
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Affiliation(s)
- Tien G Pham
- Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003, USA.
| | - Jiahui Wu
- Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003, USA.
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21
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Zhang F, Bischof H, Burgstaller S, Bourgeois BMR, Malli R, Madl T. Genetically encoded fluorescent sensor to monitor intracellular arginine methylation. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 2024; 252:112867. [PMID: 38368636 DOI: 10.1016/j.jphotobiol.2024.112867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 02/03/2024] [Accepted: 02/12/2024] [Indexed: 02/20/2024]
Abstract
Arginine methylation (ArgMet), as a post-translational modification, plays crucial roles in RNA processing, transcriptional regulation, signal transduction, DNA repair, apoptosis and liquid-liquid phase separation (LLPS). Since arginine methylation is associated with cancer pathogenesis and progression, protein arginine methyltransferases have gained interest as targets for anti-cancer therapy. Despite considerable process made to elucidate (patho)physiological mechanisms regulated by arginine methylation, there remains a lack of tools to visualize arginine methylation with high spatiotemporal resolution in live cells. To address this unmet need, we generated an ArgMet-sensitive genetically encoded, Förster resonance energy transfer-(FRET) based biosensor, called GEMS, capable of quantitative real-time monitoring of ArgMet dynamics. We optimized these biosensors by using different ArgMet-binding domains, arginine-glycine-rich regions and adjusting the linkers within the biosensors to improve their performance. Using a set of mammalian cell lines and modulators, we demonstrated the applicability of GEMS for monitoring changes in arginine methylation with single-cell and temporal resolution. The GEMS can facilitate the in vitro screening to find potential protein arginine methyltransferase inhibitors and will contribute to a better understanding of the regulation of ArgMet related to differentiation, development and disease.
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Affiliation(s)
- Fangrong Zhang
- Key Laboratory of Gastrointestinal Cancer (Fujian Medical University), Ministry of Education, Fuzhou 350122, China; Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria
| | - Helmut Bischof
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria
| | - Sandra Burgstaller
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria
| | - Benjamin M R Bourgeois
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria; Otto Loewi Research Center, Medicinal Chemistry, Medical University of Graz, 8010 Graz, Austria
| | - Roland Malli
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria; BioTechMed-Graz, 8010 Graz, Austria
| | - Tobias Madl
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria; Otto Loewi Research Center, Medicinal Chemistry, Medical University of Graz, 8010 Graz, Austria; BioTechMed-Graz, 8010 Graz, Austria.
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22
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Schulte M, Grotheer L, Hensel M. Bright individuals: Applications of fluorescent protein-based reporter systems in single-cell cellular microbiology. Mol Microbiol 2024; 121:605-617. [PMID: 38234267 DOI: 10.1111/mmi.15227] [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: 07/18/2023] [Revised: 12/30/2023] [Accepted: 01/02/2024] [Indexed: 01/19/2024]
Abstract
Activation and function of virulence functions of bacterial pathogens are highly dynamic in time and space, and can show considerable heterogeneity between individual cells in pathogen populations. To investigate the complex events in host-pathogen interactions, single cell analyses are required. Fluorescent proteins (FPs) are excellent tools to follow the fate of individual bacterial cells during infection, and can also be deployed to use the pathogen as a sensor for its specific environment in host cells or host organisms. This Resources describes design and applications of dual fluorescence reporters (DFR) in cellular microbiology. DFR feature constitutively expressed FPs for detection of bacterial cells, and FPs expressed by an environmentally regulated promoter for interrogation of niche-specific cues or nutritional parameters. Variations of the basic design allow the generation of DFR that can be used to analyze, on single cell level, bacterial proliferation during infection, subcellular localization of intracellular bacteria, stress response, or persister state. We describe basic considerations for DFR design and review recent applications of DFR in cellular microbiology.
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Affiliation(s)
- Marc Schulte
- Abt. Mikrobiologie, Universität Osnabrück, Osnabrück, Germany
- CellNanOs-Center of Cellular Nanoanalytics Osnabrück, Universität Osnabrück, Osnabrück, Germany
| | - Luisa Grotheer
- Abt. Mikrobiologie, Universität Osnabrück, Osnabrück, Germany
| | - Michael Hensel
- Abt. Mikrobiologie, Universität Osnabrück, Osnabrück, Germany
- CellNanOs-Center of Cellular Nanoanalytics Osnabrück, Universität Osnabrück, Osnabrück, Germany
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23
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Seo PW, Kim GJ, Kim JS. A short guide on blue fluorescent proteins: limits and perspectives. Appl Microbiol Biotechnol 2024; 108:208. [PMID: 38353763 PMCID: PMC10866763 DOI: 10.1007/s00253-024-13012-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 01/09/2024] [Accepted: 01/11/2024] [Indexed: 02/16/2024]
Abstract
The advent of the so-called colorful biology era is in line with the discovery of fluorescent proteins (FPs), which can be widely used to detect the intracellular locations of macromolecules or to determine the abundance of metabolites in organelles. The application of multiple FPs that emit different spectra and colors could be implemented to precisely evaluate cellular events. FPs were initially established with the emergence of the green fluorescent protein (GFP) from jellyfish. Red fluorescent proteins (RFPs) from marine anemones and several corals adopt fluorescent chromophores that are similar to GFP. Chromophores of GFP and GFP-like FPs are formed through the oxidative rearrangement of three chromophore-forming residues, thereby limiting their application to only oxidative environments. Alternatively, some proteins can be fluorescent upon their interaction with cellular prosthetic cofactors and, thus, work in aerobic and anaerobic conditions. The modification of an NADPH-dependent blue fluorescent protein (BFP) also expanded its application to the quantization of NADPH in the cellular environment. However, cofactor-dependent BFPs have an intrinsic weakness of poor photostability with a high fluorescent background. This review explores GFP-derived and NADPH-dependent BFPs with a focus on NADPH-dependent BFPs, which might be technically feasible in the near future upon coupling with two-photon fluorescence microscopy or nucleic acid-mimickers. KEY POINTS: • Oxidation-dependent GFP-like BFPs and redox-free NADPH-dependent BFPs • GFPs of weak photostability and intensity with a high fluorescent background • Real-time imaging using mBFP under two-photon fluorescence microscopy.
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Affiliation(s)
- Pil-Won Seo
- Department of Chemistry, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Geun-Joong Kim
- Department of Biological Sciences, Chonnam National University, Gwangju, 61186, Republic of Korea.
| | - Jeong-Sun Kim
- Department of Chemistry, Chonnam National University, Gwangju, 61186, Republic of Korea.
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24
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Robinson AO, Lee J, Cameron A, Keating CD, Adamala KP. Cell-Free Expressed Membraneless Organelles Inhibit Translation in Synthetic Cells. ACS Biomater Sci Eng 2024; 10:773-781. [PMID: 38226971 DOI: 10.1021/acsbiomaterials.3c01052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2024]
Abstract
Compartments within living cells create specialized microenvironments, allowing multiple reactions to be carried out simultaneously and efficiently. While some organelles are bound by a lipid bilayer, others are formed by liquid-liquid phase separation such as P-granules and nucleoli. Synthetic minimal cells are widely used to study many natural processes, including organelle formation. In this work, synthetic cells expressing artificial membrane-less organelles that inhibit translation are described. RGG-GFP-RGG, a phase-separating protein derived from Caenorhabditis elegans P-granules, is expressed by cell-free transcription and translation, forming artificial membraneless organelles that can sequester RNA and reduce protein expression in synthetic cells. The introduction of artificial membrane-less organelles creates complex microenvironments within the synthetic cell cytoplasm and functions as a tool to inhibit protein expression in synthetic cells. The engineering of compartments within synthetic cells furthers the understanding of the evolution and function of natural organelles and facilitates the creation of more complex and multifaceted synthetic lifelike systems.
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Affiliation(s)
- Abbey O Robinson
- Department of Genetics, Cell Biology and Development, University of Minnesota, 420 SE Washington Ave., Minneapolis, Minnesota 55455, United States
| | - Jessica Lee
- Department of Chemistry, The Pennsylvania State University, 104 Chemistry Building, University Park, Pennsylvania 16802, United States
| | - Anders Cameron
- Department of Genetics, Cell Biology and Development, University of Minnesota, 420 SE Washington Ave., Minneapolis, Minnesota 55455, United States
| | - Christine D Keating
- Department of Chemistry, The Pennsylvania State University, 104 Chemistry Building, University Park, Pennsylvania 16802, United States
| | - Katarzyna P Adamala
- Department of Genetics, Cell Biology and Development, University of Minnesota, 420 SE Washington Ave., Minneapolis, Minnesota 55455, United States
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25
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Moses D, Guadalupe K, Yu F, Flores E, Perez AR, McAnelly R, Shamoon NM, Kaur G, Cuevas-Zepeda E, Merg AD, Martin EW, Holehouse AS, Sukenik S. Structural biases in disordered proteins are prevalent in the cell. Nat Struct Mol Biol 2024; 31:283-292. [PMID: 38177684 PMCID: PMC10873198 DOI: 10.1038/s41594-023-01148-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 10/04/2023] [Indexed: 01/06/2024]
Abstract
Intrinsically disordered proteins and protein regions (IDPs) are prevalent in all proteomes and are essential to cellular function. Unlike folded proteins, IDPs exist in an ensemble of dissimilar conformations. Despite this structural plasticity, intramolecular interactions create sequence-specific structural biases that determine an IDP ensemble's three-dimensional shape. Such structural biases can be key to IDP function and are often measured in vitro, but whether those biases are preserved inside the cell is unclear. Here we show that structural biases in IDP ensembles found in vitro are recapitulated inside human-derived cells. We further reveal that structural biases can change in a sequence-dependent manner due to changes in the intracellular milieu, subcellular localization, and intramolecular interactions with tethered well-folded domains. We propose that the structural sensitivity of IDP ensembles can be leveraged for biological function, can be the underlying cause of IDP-driven pathology or can be used to design disorder-based biosensors and actuators.
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Affiliation(s)
- David Moses
- Department of Chemistry and Biochemistry, University of California, Merced, Merced, CA, USA
- Center for Cellular and Biomolecular Machines, University of California, Merced, Merced, CA, USA
| | - Karina Guadalupe
- Department of Chemistry and Biochemistry, University of California, Merced, Merced, CA, USA
- Center for Cellular and Biomolecular Machines, University of California, Merced, Merced, CA, USA
| | - Feng Yu
- Center for Cellular and Biomolecular Machines, University of California, Merced, Merced, CA, USA
- Quantitative and Systems Biology Program, University of California, Merced, Merced, CA, USA
| | - Eduardo Flores
- Department of Chemistry and Biochemistry, University of California, Merced, Merced, CA, USA
- Center for Cellular and Biomolecular Machines, University of California, Merced, Merced, CA, USA
| | - Anthony R Perez
- Department of Chemistry and Biochemistry, University of California, Merced, Merced, CA, USA
- Center for Cellular and Biomolecular Machines, University of California, Merced, Merced, CA, USA
| | - Ralph McAnelly
- Department of Chemistry and Biochemistry, University of California, Merced, Merced, CA, USA
| | - Nora M Shamoon
- Center for Cellular and Biomolecular Machines, University of California, Merced, Merced, CA, USA
- California State University, Stanislaus, Turlock, CA, USA
| | - Gagandeep Kaur
- Department of Chemistry and Biochemistry, University of California, Merced, Merced, CA, USA
| | | | - Andrea D Merg
- Department of Chemistry and Biochemistry, University of California, Merced, Merced, CA, USA
- Center for Cellular and Biomolecular Machines, University of California, Merced, Merced, CA, USA
| | - Erik W Martin
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN, USA
- Dewpoint Therapeutics, Boston, MA, USA
| | - Alex S Holehouse
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO, USA
- Center for Science and Engineering of Living Systems, Washington University in St. Louis, St. Louis, MO, USA
| | - Shahar Sukenik
- Department of Chemistry and Biochemistry, University of California, Merced, Merced, CA, USA.
- Center for Cellular and Biomolecular Machines, University of California, Merced, Merced, CA, USA.
- Quantitative and Systems Biology Program, University of California, Merced, Merced, CA, USA.
- Health Sciences Research Institute, University of California, Merced, Merced, CA, USA.
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26
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Mersch SA, Bergman S, Sheets ED, Boersma AJ, Heikal AA. Two-photon excited-state dynamics of mEGFP-linker-mScarlet-I crowding biosensor in controlled environments. Phys Chem Chem Phys 2024; 26:3927-3940. [PMID: 38231116 DOI: 10.1039/d3cp04733d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2024]
Abstract
Macromolecular crowding affects many cellular processes such as diffusion, biochemical reaction kinetics, protein-protein interactions, and protein folding. Mapping the heterogeneous, dynamic crowding in living cells or tissues requires genetically encoded, site-specific, crowding sensors that are compatible with quantitative, noninvasive fluorescence micro-spectroscopy. Here, we carried out time-resolved 2P-fluorescence measurements of a new mEGFP-linker-mScarlet-I macromolecular crowding construct (GE2.3) to characterize its environmental sensitivity in biomimetic crowded solutions (Ficoll-70, 0-300 g L-1) via Förster resonance energy transfer (FRET) analysis. The 2P-fluorescence lifetime of the donor (mEGFP) was measured under magic-angle polarization, in the presence (intact) and absence (enzymatically cleaved) of the acceptor (mScarlet-I), as a function of the Ficoll-70 concentration. The FRET efficiency was used to quantify the sensitivity of GE2.3 to macromolecular crowding and to determine the environmental dependence of the mEGFP-mScarlet-I distance. We also carried out time-resolved 2P-fluorescence depolarization anisotropy to examine both macromolecular crowding and linker flexibility effects on GE2.3 rotational dynamics within the context of the Stokes-Einstein model as compared with theoretical predictions based on its molecular weight. These time-resolved 2P-fluorescence depolarization measurements and conformational population analyses of GE2.3 were also used to estimate the free energy gain upon the structural collapse in crowded environment. Our results further the development of a rational engineering design for bioenvironmental sensors without the interference of cellular autofluorescence. Additionally, these results in well-defined environments will inform our future in vivo studies of genetically encoded GE2.3 towards the mapping of the crowded intracellular environment under different physiological conditions.
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Affiliation(s)
- Sarah A Mersch
- Department of Chemistry and Biochemistry, Swenson College of Science and Engineering, University of Minnesota Duluth, Duluth, MN 55812, USA.
| | - Sarah Bergman
- Department of Chemistry and Biochemistry, Swenson College of Science and Engineering, University of Minnesota Duluth, Duluth, MN 55812, USA.
| | - Erin D Sheets
- Department of Chemistry and Biochemistry, Swenson College of Science and Engineering, University of Minnesota Duluth, Duluth, MN 55812, USA.
| | - Arnold J Boersma
- Cellular Protein Chemistry, Bijvoet Centre for Biomolecular Research, Faculty of Science, Utrecht University, Utrecht, The Netherlands
| | - Ahmed A Heikal
- Department of Chemistry and Biochemistry, Swenson College of Science and Engineering, University of Minnesota Duluth, Duluth, MN 55812, USA.
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27
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Tessier E, Cheutin L, Garnier A, Vigne C, Tournier JN, Rougeaux C. Early Circulating Edema Factor in Inhalational Anthrax Infection: Does It Matter? Microorganisms 2024; 12:308. [PMID: 38399712 PMCID: PMC10891819 DOI: 10.3390/microorganisms12020308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 01/22/2024] [Accepted: 01/26/2024] [Indexed: 02/25/2024] Open
Abstract
Anthrax toxins are critical virulence factors of Bacillus anthracis and Bacillus cereus strains that cause anthrax-like disease, composed of a common binding factor, the protective antigen (PA), and two enzymatic proteins, lethal factor (LF) and edema factor (EF). While PA is required for endocytosis and activity of EF and LF, several studies showed that these enzymatic factors disseminate within the body in the absence of PA after intranasal infection. In an effort to understand the impact of EF in the absence of PA, we used a fluorescent EF chimera to facilitate the study of endocytosis in different cell lines. Unexpectedly, EF was found inside cells in the absence of PA and showed a pole-dependent endocytosis. However, looking at enzymatic activity, PA was still required for EF to induce an increase in intracellular cAMP levels. Interestingly, the sequential delivery of EF and then PA rescued the rise in cAMP levels, indicating that PA and EF may functionally associate during intracellular trafficking, as well as it did at the cell surface. Our data shed new light on EF trafficking and the potential location of PA and EF association for optimal cytosolic delivery.
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Affiliation(s)
- Emilie Tessier
- Département des Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, 91220 Brétigny-sur-Orge, France (C.R.)
| | - Laurence Cheutin
- Département des Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, 91220 Brétigny-sur-Orge, France (C.R.)
| | - Annabelle Garnier
- Département des Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, 91220 Brétigny-sur-Orge, France (C.R.)
| | - Clarisse Vigne
- Département des Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, 91220 Brétigny-sur-Orge, France (C.R.)
| | - Jean-Nicolas Tournier
- Département des Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, 91220 Brétigny-sur-Orge, France (C.R.)
- Institut Pasteur, 75015 Paris, France
| | - Clémence Rougeaux
- Département des Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, 91220 Brétigny-sur-Orge, France (C.R.)
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28
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Lesiak L, Dadina N, Zheng S, Schelvis M, Schepartz A. A Bright, Photostable, and Far-Red Dye That Enables Multicolor, Time-Lapse, and Super-Resolution Imaging of Acidic Organelles. ACS CENTRAL SCIENCE 2024; 10:19-27. [PMID: 38292604 PMCID: PMC10823512 DOI: 10.1021/acscentsci.3c01173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 11/15/2023] [Accepted: 11/21/2023] [Indexed: 02/01/2024]
Abstract
Lysosomes have long been known for their acidic lumens and efficient degradation of cellular byproducts. In recent years, it has become clear that their function is far more sophisticated, involving multiple cell signaling pathways and interactions with other organelles. Unfortunately, their acidic interior, fast dynamics, and small size make lysosomes difficult to image with fluorescence microscopy. Here we report a far-red small molecule, HMSiR680-Me, that fluoresces only under acidic conditions, causing selective labeling of acidic organelles in live cells. HMSiR680-Me can be used alongside other far-red dyes in multicolor imaging experiments and is superior to existing lysosome probes in terms of photostability and maintaining cell health and lysosome motility. We demonstrate that HMSiR680-Me is compatible with overnight time-lapse experiments as well as time-lapse super-resolution microscopy with a frame rate of 1.5 fps for at least 1000 frames. HMSiR680-Me can also be used alongside silicon rhodamine dyes in a multiplexed super-resolution microscopy experiment to visualize interactions between mitochondria and lysosomes with only a single excitation laser and simultaneous depletion. We envision this dye permitting a more detailed study of the role of lysosomes in dynamic cellular processes and disease.
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Affiliation(s)
- Lauren Lesiak
- Department
of Chemistry, University of California,
Berkeley, Berkeley, California 94720, United States
| | - Neville Dadina
- Department
of Chemistry, University of California,
Berkeley, Berkeley, California 94720, United States
| | - Shuai Zheng
- Department
of Chemistry, University of California,
Berkeley, Berkeley, California 94720, United States
| | - Marianne Schelvis
- Department
of Chemistry, University of California,
Berkeley, Berkeley, California 94720, United States
| | - Alanna Schepartz
- Department
of Chemistry, University of California,
Berkeley, Berkeley, California 94720, United States
- Department
of Molecular and Cell Biology, University
of California, Berkeley, Berkeley, California 94720, United States
- California
Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, California 94720, United States
- Chan
Zuckerberg Biohub, San Francisco, San Francisco, California 94158, United States
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29
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Ejike JO, Sadoine M, Shen Y, Ishikawa Y, Sunal E, Hänsch S, Hamacher AB, Frommer WB, Wudick MM, Campbell RE, Kleist TJ. A Monochromatically Excitable Green-Red Dual-Fluorophore Fusion Incorporating a New Large Stokes Shift Fluorescent Protein. Biochemistry 2024; 63:171-180. [PMID: 38113455 PMCID: PMC10765376 DOI: 10.1021/acs.biochem.3c00451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 11/28/2023] [Accepted: 12/01/2023] [Indexed: 12/21/2023]
Abstract
Genetically encoded sensors enable quantitative imaging of analytes in live cells. Sensors are commonly constructed by combining ligand-binding domains with one or more sensitized fluorescent protein (FP) domains. Sensors based on a single FP can be susceptible to artifacts caused by changes in sensor levels or distribution in vivo. To develop intensiometric sensors with the capacity for ratiometric quantification, dual-FP Matryoshka sensors were generated by using a single cassette with a large Stokes shift (LSS) reference FP nested within the reporter FP (cpEGFP). Here, we present a genetically encoded calcium sensor that employs green apple (GA) Matryoshka technology by incorporating a newly designed red LSSmApple fluorophore. LSSmApple matures faster and provides an optimized excitation spectrum overlap with cpEGFP, allowing for monochromatic coexcitation with blue light. The LSS of LSSmApple results in improved emission spectrum separation from cpEGFP, thereby minimizing fluorophore bleed-through and facilitating imaging using standard dichroic and red FP (RFP) emission filters. We developed an image analysis pipeline for yeast (Saccharomyces cerevisiae) timelapse imaging that utilizes LSSmApple to segment and track cells for high-throughput quantitative analysis. In summary, we engineered a new FP, constructed a genetically encoded calcium indicator (GA-MatryoshCaMP6s), and performed calcium imaging in yeast as a demonstration.
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Affiliation(s)
- J. Obinna Ejike
- Heinrich
Heine University Düsseldorf, Faculty
of Mathematics and Natural Sciences, Institute for Molecular Physiology, Düsseldorf 40225, Germany
- Cluster
of
Excellence on Plant Sciences, Faculty of Mathematics and Natural Sciences, Heinrich Heine University Düsseldorf, Düsseldorf 40225, Germany
| | - Mayuri Sadoine
- Heinrich
Heine University Düsseldorf, Faculty
of Mathematics and Natural Sciences, Institute for Molecular Physiology, Düsseldorf 40225, Germany
| | - Yi Shen
- Department
of Chemistry, University of Alberta, Edmonton T6G 2G2, Canada
| | - Yuuma Ishikawa
- Heinrich
Heine University Düsseldorf, Faculty
of Mathematics and Natural Sciences, Institute for Molecular Physiology, Düsseldorf 40225, Germany
- Cluster
of
Excellence on Plant Sciences, Faculty of Mathematics and Natural Sciences, Heinrich Heine University Düsseldorf, Düsseldorf 40225, Germany
| | - Erdem Sunal
- Heinrich
Heine University Düsseldorf, Faculty
of Mathematics and Natural Sciences, Institute for Molecular Physiology, Düsseldorf 40225, Germany
| | - Sebastian Hänsch
- Heinrich
Heine University Düsseldorf, Faculty of Mathematics and Natural Sciences, Centre for Advanced
Imaging, Düsseldorf 40225, Germany
| | - Anna B. Hamacher
- Heinrich
Heine University Düsseldorf, Faculty of Mathematics and Natural Sciences, Centre for Advanced
Imaging, Düsseldorf 40225, Germany
| | - Wolf B. Frommer
- Heinrich
Heine University Düsseldorf, Faculty
of Mathematics and Natural Sciences, Institute for Molecular Physiology, Düsseldorf 40225, Germany
- Institute
of Transformative Bio-Molecules (WPI-ITbM) Nagoya University, Nagoya 464-8601, Japan
- Cluster
of
Excellence on Plant Sciences, Faculty of Mathematics and Natural Sciences, Heinrich Heine University Düsseldorf, Düsseldorf 40225, Germany
| | - Michael M. Wudick
- Heinrich
Heine University Düsseldorf, Faculty
of Mathematics and Natural Sciences, Institute for Molecular Physiology, Düsseldorf 40225, Germany
- Cluster
of
Excellence on Plant Sciences, Faculty of Mathematics and Natural Sciences, Heinrich Heine University Düsseldorf, Düsseldorf 40225, Germany
| | - Robert E. Campbell
- Department
of Chemistry, University of Alberta, Edmonton T6G 2G2, Canada
- Department
of Chemistry, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan
| | - Thomas J. Kleist
- Heinrich
Heine University Düsseldorf, Faculty
of Mathematics and Natural Sciences, Institute for Molecular Physiology, Düsseldorf 40225, Germany
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30
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Yu TG, Lee J, Yoon J, Choi JM, Kim DG, Heo WD, Song JJ, Kim HS. Engineering of a Fluorescent Protein for a Sensing of an Intrinsically Disordered Protein through Transition in the Chromophore State. JACS AU 2023; 3:3055-3065. [PMID: 38034956 PMCID: PMC10685427 DOI: 10.1021/jacsau.3c00445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Revised: 09/18/2023] [Accepted: 10/02/2023] [Indexed: 12/02/2023]
Abstract
Intrinsically disordered proteins (IDPs) not only play important roles in biological processes but are also linked with the pathogenesis of various human diseases. Specific and reliable sensing of IDPs is crucial for exploring their roles but remains elusive due to structural plasticity. Here, we present the development of a new type of fluorescent protein for the ratiometric sensing and tracking of an IDP. A β-strand of green fluorescent protein (GFP) was truncated, and the resulting GFP was further engineered to undergo the transition in the absorption maximum upon binding of a target motif within amyloid-β (Aβ) as a model IDP through rational design and directed evolution. Spectroscopic and structural analyses of the engineered truncated GFP demonstrated that a shift in the absorption maximum is driven by the change in the chromophore state from an anionic (460 nm) state into a neutral (390 nm) state as the Aβ binds, allowing a ratiometric detection of Aβ. The utility of the developed GFP was shown by the efficient and specific detection of an Aβ and the tracking of its conformational change and localization in astrocytes.
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Affiliation(s)
- Tae-Geun Yu
- Departement
of Biological Sciences, Korea Advanced Institute
of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Jinsu Lee
- Departement
of Biological Sciences, Korea Advanced Institute
of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Jungmin Yoon
- Departement
of Biological Sciences, Korea Advanced Institute
of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Jung Min Choi
- School
of Food Biotechnology and Nutrition, Kyungsung
University, Busan 48434, Korea
| | - Dong-Gun Kim
- Departement
of Biological Sciences, Korea Advanced Institute
of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Won Do Heo
- Departement
of Biological Sciences, Korea Advanced Institute
of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Ji-Joon Song
- Departement
of Biological Sciences, Korea Advanced Institute
of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Hak-Sung Kim
- Departement
of Biological Sciences, Korea Advanced Institute
of Science and Technology (KAIST), Daejeon 34141, Korea
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31
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Nasu Y, Aggarwal A, Le GNT, Vo CT, Kambe Y, Wang X, Beinlich FRM, Lee AB, Ram TR, Wang F, Gorzo KA, Kamijo Y, Boisvert M, Nishinami S, Kawamura G, Ozawa T, Toda H, Gordon GR, Ge S, Hirase H, Nedergaard M, Paquet ME, Drobizhev M, Podgorski K, Campbell RE. Lactate biosensors for spectrally and spatially multiplexed fluorescence imaging. Nat Commun 2023; 14:6598. [PMID: 37891202 PMCID: PMC10611801 DOI: 10.1038/s41467-023-42230-5] [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: 07/17/2023] [Accepted: 10/04/2023] [Indexed: 10/29/2023] Open
Abstract
L-Lactate is increasingly appreciated as a key metabolite and signaling molecule in mammals. However, investigations of the inter- and intra-cellular dynamics of L-lactate are currently hampered by the limited selection and performance of L-lactate-specific genetically encoded biosensors. Here we now report a spectrally and functionally orthogonal pair of high-performance genetically encoded biosensors: a green fluorescent extracellular L-lactate biosensor, designated eLACCO2.1, and a red fluorescent intracellular L-lactate biosensor, designated R-iLACCO1. eLACCO2.1 exhibits excellent membrane localization and robust fluorescence response. To the best of our knowledge, R-iLACCO1 and its affinity variants exhibit larger fluorescence responses than any previously reported intracellular L-lactate biosensor. We demonstrate spectrally and spatially multiplexed imaging of L-lactate dynamics by coexpression of eLACCO2.1 and R-iLACCO1 in cultured cells, and in vivo imaging of extracellular and intracellular L-lactate dynamics in mice.
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Affiliation(s)
- Yusuke Nasu
- Department of Chemistry, School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan.
- PRESTO, Japan Science and Technology Agency, Chiyoda-ku, Tokyo, 102-0075, Japan.
| | - Abhi Aggarwal
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, 20147, USA
- Allen Institute for Neural Dynamics, Seattle, WA, 98109, USA
| | - Giang N T Le
- Department of Chemistry, School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
- Department of Chemistry, University of Toronto, Toronto, ON, M5S 3H6, Canada
| | - Camilla Trang Vo
- Center for Translational Neuromedicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, 2200, Denmark
| | - Yuki Kambe
- Department of Pharmacology, Graduate School of Medical and Dental Science, Kagoshima University, Sakuragaoka, Kagoshima, 890-8544, Japan
| | - Xinxing Wang
- Department of Neurobiology and Behavior, Stony Brook University, Stony Brook, NY, 11794, USA
| | - Felix R M Beinlich
- Center for Translational Neuromedicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, 2200, Denmark
| | - Ashley Bomin Lee
- Center for Translational Neuromedicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, 2200, Denmark
| | - Tina R Ram
- Hotchkiss Brain Institute, Cumming School of Medicine, Department of Physiology and Pharmacology, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Fangying Wang
- Hotchkiss Brain Institute, Cumming School of Medicine, Department of Physiology and Pharmacology, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Kelsea A Gorzo
- Hotchkiss Brain Institute, Cumming School of Medicine, Department of Physiology and Pharmacology, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Yuki Kamijo
- Department of Chemistry, School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Marc Boisvert
- CERVO Brain Research Centre, Québec, QC, G1J 2G3, Canada
- Department of Biochemistry, Microbiology and Bioinformatics, Laval University, Québec, QC, G1E 1T2, Canada
| | - Suguru Nishinami
- International Institute for Integrative Sleep Medicine, University of Tsukuba, Tsukuba, Ibaraki, 305-8575, Japan
| | - Genki Kawamura
- Department of Chemistry, School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Takeaki Ozawa
- Department of Chemistry, School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Hirofumi Toda
- International Institute for Integrative Sleep Medicine, University of Tsukuba, Tsukuba, Ibaraki, 305-8575, Japan
| | - Grant R Gordon
- Hotchkiss Brain Institute, Cumming School of Medicine, Department of Physiology and Pharmacology, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Shaoyu Ge
- Department of Neurobiology and Behavior, Stony Brook University, Stony Brook, NY, 11794, USA
| | - Hajime Hirase
- Center for Translational Neuromedicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, 2200, Denmark
- Center for Translational Neuromedicine, University of Rochester Medical Center, Rochester, NY, 14642, USA
| | - Maiken Nedergaard
- Center for Translational Neuromedicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, 2200, Denmark
- Center for Translational Neuromedicine, University of Rochester Medical Center, Rochester, NY, 14642, USA
| | - Marie-Eve Paquet
- CERVO Brain Research Centre, Québec, QC, G1J 2G3, Canada
- Department of Biochemistry, Microbiology and Bioinformatics, Laval University, Québec, QC, G1E 1T2, Canada
| | - Mikhail Drobizhev
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, 59717, USA
| | - Kaspar Podgorski
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, 20147, USA
- Allen Institute for Neural Dynamics, Seattle, WA, 98109, USA
| | - Robert E Campbell
- Department of Chemistry, School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan.
- CERVO Brain Research Centre, Québec, QC, G1J 2G3, Canada.
- Department of Biochemistry, Microbiology and Bioinformatics, Laval University, Québec, QC, G1E 1T2, Canada.
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32
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Höger B, Peifer C, Beitz E. Cell-free production of fluorescent proteins for the discovery of novel ribosome-targeting antibiotics. J Microbiol Methods 2023; 213:106814. [PMID: 37652138 DOI: 10.1016/j.mimet.2023.106814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 08/14/2023] [Accepted: 08/29/2023] [Indexed: 09/02/2023]
Abstract
Various issues including the overuse of antibiotics has led to the development of threatening multidrug-resistant bacterial strains urging development of novel anti-infectives. One quarter of current clinical phase III antibiotic drug candidates address ribosomal protein translation as a target. Here, we describe an effective cell-free in vitro screening system for inhibitors of bacterial ribosome activity with direct fluorescence read-out. Using ribosomal S30 extracts from Escherichia coli, Salmonella enterica, and Pseudomonas putida, the validity of this system is demonstrated by concentration-dependent inhibition of translation by a set of different classes of translation-targeting drugs. The single-compartment cell-free translation reaction is compatible with multi-well formats. Fluorophore formation of green fluorescent protein or monomeric NeonGreen occurs in an hour time frame without the need of adding reagents for secondary enzymatic detection saving handling time, and prohibiting false positives. As label-free readout, the dose response further allows for IC50 determination in the same setup. Together, we show that cell-free production of fluorescent proteins for the discovery of ribosome-targeting antibiotics is feasible and amenable to high-throughput applications.
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Affiliation(s)
- Bastian Höger
- Department of Pharmaceutical and Medicinal Chemistry, Christian-Albrechts-University of Kiel, Gutenbergstraße 76, Kiel, Germany
| | - Christian Peifer
- Department of Pharmaceutical and Medicinal Chemistry, Christian-Albrechts-University of Kiel, Gutenbergstraße 76, Kiel, Germany
| | - Eric Beitz
- Department of Pharmaceutical and Medicinal Chemistry, Christian-Albrechts-University of Kiel, Gutenbergstraße 76, Kiel, Germany.
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Zhang H, Papadaki S, Sun X, Wang X, Drobizhev M, Yao L, Rehbock M, Köster RW, Wu L, Namikawa K, Piatkevich KD. Quantitative assessment of near-infrared fluorescent proteins. Nat Methods 2023; 20:1605-1616. [PMID: 37666982 DOI: 10.1038/s41592-023-01975-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 06/29/2023] [Indexed: 09/06/2023]
Abstract
Recent progress in fluorescent protein development has generated a large diversity of near-infrared fluorescent proteins (NIR FPs), which are rapidly becoming popular probes for a variety of imaging applications. However, the diversity of NIR FPs poses a challenge for end-users in choosing the optimal one for a given application. Here we conducted a systematic and quantitative assessment of intracellular brightness, photostability, oligomeric state, chemical stability and cytotoxicity of 22 NIR FPs in cultured mammalian cells and primary mouse neurons and identified a set of top-performing FPs including emiRFP670, miRFP680, miRFP713 and miRFP720, which can cover a majority of imaging applications. The top-performing proteins were further validated for in vivo imaging of neurons in Caenorhabditis elegans, zebrafish, and mice as well as in mice liver. We also assessed the applicability of the selected NIR FPs for multicolor imaging of fusions, expansion microscopy and two-photon imaging.
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Affiliation(s)
- Hanbin Zhang
- School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China
| | - Stavrini Papadaki
- School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China
| | - Xiaoting Sun
- School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China
| | - Xinyue Wang
- Division of Cellular and Molecular Neurobiology, Zoological Institute, Technische Universität Braunschweig, Braunschweig, Germany
| | - Mikhail Drobizhev
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, USA
| | - Luxia Yao
- School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China
| | - Michel Rehbock
- Division of Cellular and Molecular Neurobiology, Zoological Institute, Technische Universität Braunschweig, Braunschweig, Germany
| | - Reinhard W Köster
- Division of Cellular and Molecular Neurobiology, Zoological Institute, Technische Universität Braunschweig, Braunschweig, Germany
| | - Lianfeng Wu
- School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China
| | - Kazuhiko Namikawa
- Division of Cellular and Molecular Neurobiology, Zoological Institute, Technische Universität Braunschweig, Braunschweig, Germany
| | - Kiryl D Piatkevich
- School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China.
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China.
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China.
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Hoshino N, Kanadome T, Takasugi T, Itoh M, Kaneko R, Inoue YU, Inoue T, Hirabayashi T, Watanabe M, Matsuda T, Nagai T, Tarusawa E, Yagi T. Visualization of trans homophilic interaction of clustered protocadherin in neurons. Proc Natl Acad Sci U S A 2023; 120:e2301003120. [PMID: 37695902 PMCID: PMC10515168 DOI: 10.1073/pnas.2301003120] [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: 01/17/2023] [Accepted: 07/20/2023] [Indexed: 09/13/2023] Open
Abstract
Clustered protocadherin (Pcdh) functions as a cell recognition molecule through the homophilic interaction in the central nervous system. However, its interactions have not yet been visualized in neurons. We previously reported PcdhγB2-Förster resonance energy transfer (FRET) probes to be applicable only to cell lines. Herein, we designed γB2-FRET probes by fusing FRET donor and acceptor fluorescent proteins to a single γB2 molecule and succeeded in visualizing γB2 homophilic interaction in cultured hippocampal neurons. The γB2-FRET probe localized in the soma and neurites, and FRET signals, which were observed at contact sites between neurites, eliminated by ethylene glycol tetraacetic acid (EGTA) addition. Live imaging revealed that the FRET-negative γB2 signals rapidly moved along neurites and soma, whereas the FRET-positive signals remained in place. We observed that the γB2 proteins at synapses rarely interact homophilically. The γB2-FRET probe might allow us to elucidate the function of the homophilic interaction and the cell recognition mechanism.
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Affiliation(s)
- Natsumi Hoshino
- KOKORO-Biology Group, Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka565-0871, Japan
| | - Takashi Kanadome
- Department of Biomolecular Science and Engineering, SANKEN, Osaka University, Ibaraki, Osaka567-0047, Japan
- Japan Science and Technology Agency, Precursory Research for Embryonic Science and Technology, Kawaguchi, Saitama332-0012, Japan
| | - Tomomi Takasugi
- KOKORO-Biology Group, Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka565-0871, Japan
| | - Mizuho Itoh
- KOKORO-Biology Group, Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka565-0871, Japan
| | - Ryosuke Kaneko
- KOKORO-Biology Group, Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka565-0871, Japan
| | - Yukiko U. Inoue
- Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo187-8501, Japan
| | - Takayoshi Inoue
- Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo187-8501, Japan
| | - Takahiro Hirabayashi
- KOKORO-Biology Group, Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka565-0871, Japan
- Clinical Medicine Research Laboratory, Shonan University of Medical Sciences, Yokohama244-0806, Japan
| | - Masahiko Watanabe
- Department of Anatomy, Faculty of Medicine, Hokkaido University, Sapporo, Hokkaido060-8638, Japan
| | - Tomoki Matsuda
- Department of Biomolecular Science and Engineering, SANKEN, Osaka University, Ibaraki, Osaka567-0047, Japan
| | - Takeharu Nagai
- Department of Biomolecular Science and Engineering, SANKEN, Osaka University, Ibaraki, Osaka567-0047, Japan
| | - Etsuko Tarusawa
- KOKORO-Biology Group, Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka565-0871, Japan
| | - Takeshi Yagi
- KOKORO-Biology Group, Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka565-0871, Japan
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Feldmann C, Schänzler M, Ben-Johny M, Wahl-Schott C. Protocol for deriving proximity, affinity, and stoichiometry of protein interactions using image-based quantitative two-hybrid FRET. STAR Protoc 2023; 4:102459. [PMID: 37516972 PMCID: PMC10400964 DOI: 10.1016/j.xpro.2023.102459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 05/26/2023] [Accepted: 06/22/2023] [Indexed: 08/01/2023] Open
Abstract
Two-hybrid Förster resonance energy transfer (FRET) provides proximity, affinity, and stoichiometry information in binding interactions. We present an image-based approach that surpasses traditional two-hybrid FRET assays in precision and robustness. We outline instrument setup and image acquisition and further describe steps for image preprocessing and two-hybrid FRET analysis using provided software to simplify the workflow. This protocol is compatible with confocal microscopes for high-precision and imaging plate readers for high-throughput applications. A plasmid-based reference system supports fast establishment of the protocol. For complete details on the use and execution of this protocol, please refer to Rivas et al.1.
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Affiliation(s)
- Colin Feldmann
- Institute of Cardiovascular Physiology and Pathophysiology, Faculty of Medicine, Biomedical Center, LMU-Munich, 82152 Planegg-Martinsried, Germany; Institute of Neurophysiology, Medizinische Hochschule Hannover, 30625 Hannover, Germany
| | - Michael Schänzler
- Institute of Neurophysiology, Medizinische Hochschule Hannover, 30625 Hannover, Germany
| | - Manu Ben-Johny
- Department of Physiology and Cellular Biophysics, Columbia University, Medical Center, New York 10032, NY, USA
| | - Christian Wahl-Schott
- Institute of Cardiovascular Physiology and Pathophysiology, Faculty of Medicine, Biomedical Center, LMU-Munich, 82152 Planegg-Martinsried, Germany; Institute of Neurophysiology, Medizinische Hochschule Hannover, 30625 Hannover, Germany.
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Shen Y, Wen Y, Sposini S, Vishwanath AA, Abdelfattah AS, Schreiter ER, Lemieux MJ, de Juan-Sanz J, Perrais D, Campbell RE. Rational Engineering of an Improved Genetically Encoded pH Sensor Based on Superecliptic pHluorin. ACS Sens 2023; 8:3014-3022. [PMID: 37481776 DOI: 10.1021/acssensors.3c00484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/25/2023]
Abstract
Genetically encoded pH sensors based on fluorescent proteins are valuable tools for the imaging of cellular events that are associated with pH changes, such as exocytosis and endocytosis. Superecliptic pHluorin (SEP) is a pH-sensitive green fluorescent protein (GFP) variant widely used for such applications. Here, we report the rational design, development, structure, and applications of Lime, an improved SEP variant with higher fluorescence brightness and greater pH sensitivity. The X-ray crystal structure of Lime supports the mechanistic rationale that guided the introduction of beneficial mutations. Lime provides substantial improvements relative to SEP for imaging of endocytosis and exocytosis. Furthermore, Lime and its variants are advantageous for a broader range of applications including the detection of synaptic release and neuronal voltage changes.
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Affiliation(s)
- Yi Shen
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Yurong Wen
- Department of Biochemistry, Faculty of Medicine & Dentistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada
- Center for Microbiome Research of Med-X Institute, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, China
| | - Silvia Sposini
- CNRS, Interdisciplinary Institute for Neuroscience, UMR 5297, University of Bordeaux, Bordeaux 33076, France
- Department of Metabolism, Digestion and Reproduction, Institute of Reproductive and Developmental Biology, Imperial College London, London SW7 2BX, United Kingdom
| | - Anjali Amrapali Vishwanath
- Institut du Cerveau-Paris Brain Institute-ICM, Inserm, CNRS, APHP, Häpital de la Pitié Salpêtrière, Sorbonne Université, 75013 Paris, France
| | - Ahmed S Abdelfattah
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, Virgina 20147, United States
- Department of Neuroscience, Brown University, Providence, Rhode Island 02906, United States
| | - Eric R Schreiter
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, Virgina 20147, United States
| | - M Joanne Lemieux
- Department of Biochemistry, Faculty of Medicine & Dentistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada
| | - Jaime de Juan-Sanz
- Institut du Cerveau-Paris Brain Institute-ICM, Inserm, CNRS, APHP, Häpital de la Pitié Salpêtrière, Sorbonne Université, 75013 Paris, France
| | - David Perrais
- CNRS, Interdisciplinary Institute for Neuroscience, UMR 5297, University of Bordeaux, Bordeaux 33076, France
| | - Robert E Campbell
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
- Department of Chemistry, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan
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37
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Snyder GA, Kumar S, Lewis GK, Ray K. Two-photon fluorescence lifetime imaging microscopy of NADH metabolism in HIV-1 infected cells and tissues. Front Immunol 2023; 14:1213180. [PMID: 37662898 PMCID: PMC10468605 DOI: 10.3389/fimmu.2023.1213180] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 07/21/2023] [Indexed: 09/05/2023] Open
Abstract
Rapid detection of microbial-induced cellular changes during the course of an infection is critical to understanding pathogenesis and immunological homeostasis. In the last two decades, fluorescence imaging has received significant attention for its ability to help characterize microbial induced cellular and tissue changes in in vitro and in vivo settings. However, most of these methods rely on the covalent conjugation of large exogenous probes and detection methods based on intensity-based imaging. Here, we report a quantitative, intrinsic, label-free, and minimally invasive method based on two-photon fluorescence lifetime (FLT) imaging microscopy (2p-FLIM) for imaging 1,4-dihydro-nicotinamide adenine dinucleotide (NADH) metabolism of virally infected cells and tissue sections. To better understand virally induced cellular and tissue changes in metabolism we have used 2p-FLIM to study differences in NADH intensity and fluorescence lifetimes in HIV-1 infected cells and tissues. Differences in NADH fluorescence lifetimes are associated with cellular changes in metabolism and changes in cellular metabolism are associated with HIV-1 infection. NADH is a critical co-enzyme and redox regulator and an essential biomarker in the metabolic processes. Label-free 2p-FLIM application and detection of NADH fluorescence using viral infection systems are in their infancy. In this study, the application of the 2p-FLIM assay and quantitative analyses of HIV-1 infected cells and tissue sections reveal increased fluorescence lifetime and higher enzyme-bound NADH fraction suggesting oxidative phosphorylation (OxPhos) compared to uninfected cells and tissues. 2p-FLIM measurements improve signal to background, fluorescence specificity, provide spatial and temporal resolution of intracellular structures, and thus, are suitable for quantitative studies of cellular functions and tissue morphology. Furthermore, 2p-FLIM allows distinguishing free and bound populations of NADH by their different fluorescence lifetimes within single infected cells. Accordingly, NADH fluorescence measurements of individual single cells should provide necessary insight into the heterogeneity of metabolic activity of infected cells. Implementing 2p-FLIM to viral infection systems measuring NADH fluorescence at the single or subcellular level within a tissue can provide visual evidence, localization, and information in a real-time diagnostic or therapeutic metabolic workflow.
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Affiliation(s)
- Greg A. Snyder
- Division of Vaccine Research, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD, United States
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Sameer Kumar
- Division of Vaccine Research, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - George K. Lewis
- Division of Vaccine Research, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD, United States
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Krishanu Ray
- Division of Vaccine Research, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD, United States
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, United States
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Schubert V, Weißleder A, Lermontova I. Simultaneous EYFP-CENH3/H2B-DsRed Expression Is Impaired Differentially in Meristematic and Differentiated Nuclei of Arabidopsis Double Transformants. Cytogenet Genome Res 2023; 163:74-80. [PMID: 37552957 DOI: 10.1159/000533317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 07/28/2023] [Indexed: 08/10/2023] Open
Abstract
Fluorescence live-cell microscopy is important in cell biology to perform artifact-free investigations. To analyze the dynamics of chromatin and centromeres at different stages of the cell cycle in nuclei and chromosomes, we performed simultaneous EYFP-CENH3/H2B-DsRed and single H2B-YFP transformations in Arabidopsis wild-type and cohesin T-DNA mutants. All constructs were under the control of the strong CaMV 35S promoter. While a strong silencing of fluorescence expression occurred differently in leaf and root tissues in the double transformants, nearly all single-transformed wild-type and most mutant cells showed H2B-YFP fluorescence. It seems that for an efficient co-expression of two fluorescence proteins, endogenous promoters and terminators should be used.
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Affiliation(s)
- Veit Schubert
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Seeland, Germany
| | - Andrea Weißleder
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Seeland, Germany
| | - Inna Lermontova
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Seeland, Germany
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Lesiak L, Dadina N, Zheng S, Schelvis M, Schepartz A. A Bright, Photostable Dye that Enables Multicolor, Time Lapse, and Super-Resolution Imaging of Acidic Organelles. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.04.552058. [PMID: 37577591 PMCID: PMC10418513 DOI: 10.1101/2023.08.04.552058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Lysosomes have long been known for their acidic lumen and efficient degradation of cellular byproducts. In recent years it has become clear that their function is far more sophisticated, involving multiple cell signaling pathways and interactions with other organelles. Unfortunately, their acidic interior, fast dynamics, and small size makes lysosomes difficult to image with fluorescence microscopy. Here we report a far-red small molecule, HMSiR680-Me, that fluoresces only under acidic conditions, causing selective labeling of acidic organelles in live cells. HMSiR680-Me can be used alongside other far-red dyes in multicolor imaging experiments and is superior to existing lysosome probes in terms of photostability and maintaining cell health and lysosome motility. We demonstrate that HMSiR680-Me is compatible with overnight time lapse experiments, as well as time lapse super-resolution microscopy with a fast frame rate for at least 1000 frames. HMSiR680-Me can also be used alongside silicon rhodamine dyes in a multiplexed super-resolution microscopy experiment to visualize interactions between the inner mitochondrial membrane and lysosomes with only a single excitation laser and simultaneous depletion. We envision this dye permitting more detailed study of the role of lysosomes in dynamic cellular processes and disease.
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Affiliation(s)
- Lauren Lesiak
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Neville Dadina
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Shuai Zheng
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Marianne Schelvis
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Alanna Schepartz
- Department of Chemistry, University of California, Berkeley, California 94720, United States
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Petrich A, Aji AK, Dunsing V, Chiantia S. Benchmarking of novel green fluorescent proteins for the quantification of protein oligomerization in living cells. PLoS One 2023; 18:e0285486. [PMID: 37535571 PMCID: PMC10399874 DOI: 10.1371/journal.pone.0285486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 04/25/2023] [Indexed: 08/05/2023] Open
Abstract
Protein-protein-interactions play an important role in many cellular functions. Quantitative non-invasive techniques are applied in living cells to evaluate such interactions, thereby providing a broader understanding of complex biological processes. Fluorescence fluctuation spectroscopy describes a group of quantitative microscopy approaches for the characterization of molecular interactions at single cell resolution. Through the obtained molecular brightness, it is possible to determine the oligomeric state of proteins. This is usually achieved by fusing fluorescent proteins (FPs) to the protein of interest. Recently, the number of novel green FPs has increased, with consequent improvements to the quality of fluctuation-based measurements. The photophysical behavior of FPs is influenced by multiple factors (including photobleaching, protonation-induced "blinking" and long-lived dark states). Assessing these factors is critical for selecting the appropriate fluorescent tag for live cell imaging applications. In this work, we focus on novel green FPs that are extensively used in live cell imaging. A systematic performance comparison of several green FPs in living cells under different pH conditions using Number & Brightness (N&B) analysis and scanning fluorescence correlation spectroscopy was performed. Our results show that the new FP Gamillus exhibits higher brightness at the cost of lower photostability and fluorescence probability (pf), especially at lower pH. mGreenLantern, on the other hand, thanks to a very high pf, is best suited for multimerization quantification at neutral pH. At lower pH, mEGFP remains apparently the best choice for multimerization investigation. These guidelines provide the information needed to plan quantitative fluorescence microscopy involving these FPs, both for general imaging or for protein-protein-interactions quantification via fluorescence fluctuation-based methods.
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Affiliation(s)
- Annett Petrich
- University of Potsdam, Institute of Biochemistry and Biology, Potsdam, Germany
| | - Amit Koikkarah Aji
- University of Potsdam, Institute of Biochemistry and Biology, Potsdam, Germany
| | - Valentin Dunsing
- University of Potsdam, Institute of Biochemistry and Biology, Potsdam, Germany
- Aix-Marseille University, CNRS, UMR 7288, IBDM, Turing Center for Living Systems, Marseille, France
| | - Salvatore Chiantia
- University of Potsdam, Institute of Biochemistry and Biology, Potsdam, Germany
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Dubois C, Houel-Renault L, Erard M, Boustany NN, Westbrook N. Förster resonance energy transfer efficiency measurements on vinculin tension sensors at focal adhesions using a simple and cost-effective setup. JOURNAL OF BIOMEDICAL OPTICS 2023; 28:082808. [PMID: 37441563 PMCID: PMC10335361 DOI: 10.1117/1.jbo.28.8.082808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 05/20/2023] [Accepted: 05/23/2023] [Indexed: 07/15/2023]
Abstract
Significance Forces inside cells play a fundamental role in tissue growth, affecting important processes such as cancer cell migration or tissue repair after injury. Förster resonance energy transfer (FRET)-based tension sensors are a remarkable tool for studying these forces and should be made easier to use. Aim We prove that absolute FRET efficiency can be measured on a simple setup, an order of magnitude more cost-effective than a standard FRET microscopy setup, by applying it to vinculin tension sensors (VinTS) at the focal adhesions of live CHO-K1 cells. Approach Our setup located at Université Paris-Saclay acquires donor and acceptor fluorescence in parallel on two low-cost CMOS cameras and uses two LEDs for rapid switching of the excitation wavelength at a reduced cost. The calibration required to extract FRET efficiency was achieved using a single construct (TSMod). FRET efficiencies were measured for VinTS and the tail-less control VinTL, lacking the actin-binding domain of vinculin. Measurements were confirmed on the same cell type using a more standard intensity-based setup located at Rutgers University. Results The average FRET efficiency of VinTS (22.0 % ± 4 % ) over more than 10,000 focal adhesions is significantly lower (p < 10 - 6 ) than that of VinTL (30.4 % ± 5 % ), our control that is insensitive to force, in agreement with the force exerted on vinculin at focal adhesions. Attachment of the CHO-K1 cells on fibronectin decreases FRET efficiency, thus increasing the force, compared with poly-lysine. FRET efficiency for the VinTL control is consistent with all measurements currently available in the literature, confirming the validity of our measurements and hence of our simpler setup. Conclusions Force measurements, resolved spatially inside a cell, can be achieved using FRET-based tension sensors with a cost effective intensity-based setup. This will facilitate combining FRET with techniques for applying controlled forces such as optical tweezers.
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Affiliation(s)
- Camille Dubois
- Université Paris-Saclay, Institut d’Optique Graduate School, CNRS, Laboratoire Charles Fabry, Palaiseau, France
| | - Ludivine Houel-Renault
- Université Paris-Saclay, Institut des Sciences Moléculaires d’Orsay, CNRS, Centre de Photonique pour la Biologie et les Matériaux, Orsay, France
| | - Marie Erard
- Université Paris-Saclay, Institut de Chimie Physique, CNRS, Orsay, France
| | - Nada N. Boustany
- Rutgers University, Department of Biomedical Engineering, Piscataway, New Jersey, United States
| | - Nathalie Westbrook
- Université Paris-Saclay, Institut d’Optique Graduate School, CNRS, Laboratoire Charles Fabry, Palaiseau, France
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42
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Li C, Tian Y, Liu C, Dou Z, Diao J. Effects of Heat Treatment on the Structural and Functional Properties of Phaseolus vulgaris L. Protein. Foods 2023; 12:2869. [PMID: 37569138 PMCID: PMC10417349 DOI: 10.3390/foods12152869] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 07/23/2023] [Accepted: 07/25/2023] [Indexed: 08/13/2023] Open
Abstract
The paper presents the effect of heat treatment at 80 °C at different times (3, 5, 7, and 9 min) on the structural and functional properties of Phaseolus vulgaris L. protein (PVP, bean protein powder). Surface and structure properties of PVP after heat treatment were analyzed using a Fourier transform infrared spectrometer (FTIR), a fluorescence spectrophotometer, a visible light spectrophotometer, a laser particle size analyzer, and other equipment. The secondary structure and surface hydrophobicity (H0) of PVP changed significantly after heat treatment: the β-sheet content decreased from 25.32 ± 0.09% to 24.66 ± 0.09%, the random coil content increased from 23.91 ± 0.11% to 25.68 ± 0.08%, and the H0 rose by 28.96-64.99%. In addition, the functional properties of PVP after heat treatment were analyzed. After heat treatment, the emulsifying activity index (EAI) of PVP increased from 78.52 ± 2.01 m2/g to 98.21 ± 1.33 m2/g, the foaming ability (FA) improved from 87.31 ± 2.56% to 95.82 ± 2.96%, and the foam stability (FS) rose from 53.23 ± 1.72% to 58.71 ± 2.18%. Finally, the degree of hydrolysis (DH) of PVP after gastrointestinal simulated digestion in vitro was detected by the Ortho-Phthal (OPA) method. Heat treatment enhanced the DH of PVP from 62.34 ± 0.31% to 73.64 ± 0.53%. It was confirmed that heat treatment changed the structural properties of PVP and improved its foamability, emulsification, and digestibility. It provides ideas for improving PVP's potential and producing new foods with rich nutrition, multiple functions, and easy absorption.
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Affiliation(s)
- Chaoyang Li
- National Coarse Cereal Engineering Technology Research Center, Heilongjiang Bayi Agricultural University, Daqing 163319, China; (C.L.); (Z.D.)
| | - Yachao Tian
- School of Food Science and Engineering, Qilu University of Technology, Jinan 250353, China;
| | - Caihua Liu
- College of Food Science, Northeast Agricultural University, Harbin 150030, China;
| | - Zhongyou Dou
- National Coarse Cereal Engineering Technology Research Center, Heilongjiang Bayi Agricultural University, Daqing 163319, China; (C.L.); (Z.D.)
| | - Jingjing Diao
- National Coarse Cereal Engineering Technology Research Center, Heilongjiang Bayi Agricultural University, Daqing 163319, China; (C.L.); (Z.D.)
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43
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Sánchez-Pedreño Jiménez A, Puhl HL, Vogel SS, Kim Y. Ultrafast fluorescence depolarisation in green fluorescence protein tandem dimers as hydrophobic environment sensitive probes. Phys Chem Chem Phys 2023; 25:19532-19539. [PMID: 37351579 PMCID: PMC10370368 DOI: 10.1039/d3cp01765f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Accepted: 06/17/2023] [Indexed: 06/24/2023]
Abstract
Advances in ultra-fast photonics have enabled monitoring of biochemical interactions on a sub nano-second time scale. In addition, picosecond dynamics of intermolecular energy transfer in fluorescent proteins has been observed. Here, we present the development of a genetically encoded fluorescent sensor that can detect changes in hydrophobicity by monitoring ultrafast fluorescence depolarisation. Our sensor is composed of a pair of dimeric enhanced green fluorescent proteins (dEGFPs) linked by a flexible amino-acid linker. We show dimerisation is perturbed by the addition of glycerol which interferes with the hydrophobic interaction of the two proteins. Time-resolved fluorescence anisotropy revealed a systematic attenuation of ultrafast fluorescence depolarisation when the sensor was exposed to increasing glycerol concentrations. This suggests that as hydrophobicity increases, dEGFP pairing decreases within a tandem dimer. Un-pairing of the protein fluorophores dramatically alters the rate of energy transfer between the proteins, resulting in an increase in the limiting anisotropy of the sensor.
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Affiliation(s)
- Alejandro Sánchez-Pedreño Jiménez
- Leverhulme Quantum Biology Doctoral Training Centre, University of Surrey, Guildford GU2 7XH, UK.
- Department of Microbial Sciences, School of Biosciences, University of Surrey, Guilford GU2 7XH, UK
- Advanced Technology Institute, University of Surrey, Guildford, GU2 7XH, UK
| | - Henry L Puhl
- Laboratory of Biophotonics and Quantum Biology, NIAAA, NIH, Bethesda, USA.
| | - Steven S Vogel
- Laboratory of Biophotonics and Quantum Biology, NIAAA, NIH, Bethesda, USA.
| | - Youngchan Kim
- Leverhulme Quantum Biology Doctoral Training Centre, University of Surrey, Guildford GU2 7XH, UK.
- Department of Microbial Sciences, School of Biosciences, University of Surrey, Guilford GU2 7XH, UK
- Advanced Technology Institute, University of Surrey, Guildford, GU2 7XH, UK
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44
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Li P, Messina G, Lehner CF. Nuclear elongation during spermiogenesis depends on physical linkage of nuclear pore complexes to bundled microtubules by Drosophila Mst27D. PLoS Genet 2023; 19:e1010837. [PMID: 37428798 PMCID: PMC10359004 DOI: 10.1371/journal.pgen.1010837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2023] [Accepted: 06/22/2023] [Indexed: 07/12/2023] Open
Abstract
Spermatozoa in animal species are usually highly elongated cells with a long motile tail attached to a head that contains the haploid genome in a compact and often elongated nucleus. In Drosophila melanogaster, the nucleus is compacted two hundred-fold in volume during spermiogenesis and re-modeled into a needle that is thirty-fold longer than its diameter. Nuclear elongation is preceded by a striking relocalization of nuclear pore complexes (NPCs). While NPCs are initially located throughout the nuclear envelope (NE) around the spherical nucleus of early round spermatids, they are later confined to one hemisphere. In the cytoplasm adjacent to this NPC-containing NE, the so-called dense complex with a strong bundle of microtubules is assembled. While this conspicuous proximity argued for functional significance of NPC-NE and microtubule bundle, experimental confirmation of their contributions to nuclear elongation has not yet been reported. Our functional characterization of the spermatid specific Mst27D protein now resolves this deficit. We demonstrate that Mst27D establishes physical linkage between NPC-NE and dense complex. The C-terminal region of Mst27D binds to the nuclear pore protein Nup358. The N-terminal CH domain of Mst27D, which is similar to that of EB1 family proteins, binds to microtubules. At high expression levels, Mst27D promotes bundling of microtubules in cultured cells. Microscopic analyses indicated co-localization of Mst27D with Nup358 and with the microtubule bundles of the dense complex. Time-lapse imaging revealed that nuclear elongation is accompanied by a progressive bundling of microtubules into a single elongated bundle. In Mst27D null mutants, this bundling process does not occur and nuclear elongation is abnormal. Thus, we propose that Mst27D permits normal nuclear elongation by promoting the attachment of the NPC-NE to the microtubules of the dense complex, as well as the progressive bundling of these microtubules.
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Affiliation(s)
- Pengfei Li
- Department of Molecular Life Science (DMLS), University of Zurich, Zurich, Switzerland
| | - Giovanni Messina
- Department of Molecular Life Science (DMLS), University of Zurich, Zurich, Switzerland
| | - Christian F Lehner
- Department of Molecular Life Science (DMLS), University of Zurich, Zurich, Switzerland
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Sanders S, Jensen Y, Reimer R, Bosse JB. From the beginnings to multidimensional light and electron microscopy of virus morphogenesis. Adv Virus Res 2023; 116:45-88. [PMID: 37524482 DOI: 10.1016/bs.aivir.2023.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/02/2023]
Abstract
Individual functional viral morphogenesis events are often dynamic, short, and infrequent and might be obscured by other pathways and dead-end products. Volumetric live cell imaging has become an essential tool for studying viral morphogenesis events. It allows following entire dynamic processes while providing functional evidence that the imaged process is involved in viral production. Moreover, it allows to capture many individual events and allows quantitative analysis. Finally, the correlation of volumetric live-cell data with volumetric electron microscopy (EM) can provide crucial insights into the ultrastructure and mechanisms of viral morphogenesis events. Here, we provide an overview and discussion of suitable imaging methods for volumetric correlative imaging of viral morphogenesis and frame them in a historical summary of their development.
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Affiliation(s)
- Saskia Sanders
- Department of Virology, Hannover Medical School, Hannover, Germany; Leibniz Institute of Virology (LIV), Hamburg, Germany; Centre for Structural Systems Biology, Hamburg, Germany; Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
| | - Yannick Jensen
- Department of Virology, Hannover Medical School, Hannover, Germany; Leibniz Institute of Virology (LIV), Hamburg, Germany; Centre for Structural Systems Biology, Hamburg, Germany; Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
| | | | - Jens B Bosse
- Department of Virology, Hannover Medical School, Hannover, Germany; Leibniz Institute of Virology (LIV), Hamburg, Germany; Centre for Structural Systems Biology, Hamburg, Germany; Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany.
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46
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Gligorovski V, Sadeghi A, Rahi SJ. Multidimensional characterization of inducible promoters and a highly light-sensitive LOV-transcription factor. Nat Commun 2023; 14:3810. [PMID: 37369667 DOI: 10.1038/s41467-023-38959-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 05/24/2023] [Indexed: 06/29/2023] Open
Abstract
The ability to independently control the expression of different genes is important for quantitative biology. Using budding yeast, we characterize GAL1pr, GALL, MET3pr, CUP1pr, PHO5pr, tetOpr, terminator-tetOpr, Z3EV, blue-light inducible optogenetic systems El222-LIP, El222-GLIP, and red-light inducible PhyB-PIF3. We report kinetic parameters, noise scaling, impact on growth, and the fundamental leakiness of each system using an intuitive unit, maxGAL1. We uncover disadvantages of widely used tools, e.g., nonmonotonic activity of MET3pr and GALL, slow off kinetics of the doxycycline- and estradiol-inducible systems tetOpr and Z3EV, and high variability of PHO5pr and red-light activated PhyB-PIF3 system. We introduce two previously uncharacterized systems: strongLOV, a more light-sensitive El222 mutant, and ARG3pr, which is induced in the absence of arginine or presence of methionine. To demonstrate fine control over gene circuits, we experimentally tune the time between cell cycle Start and mitosis, artificially simulating near-wild-type timing. All strains, constructs, code, and data ( https://promoter-benchmark.epfl.ch/ ) are made available.
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Affiliation(s)
- Vojislav Gligorovski
- Laboratory of the Physics of Biological Systems, Institute of Physics, École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Ahmad Sadeghi
- Laboratory of the Physics of Biological Systems, Institute of Physics, École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Sahand Jamal Rahi
- Laboratory of the Physics of Biological Systems, Institute of Physics, École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland.
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47
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Armoza-Eilat S, Malis Y, Caspi M, Shomron O, Hirschberg K, Rosin-Arbesfeld R. Title: The C-terminal amphipathic helix of Carboxypeptidase E mediates export from the ER and secretion via lysosomes. J Mol Biol 2023:168171. [PMID: 37285900 DOI: 10.1016/j.jmb.2023.168171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 05/29/2023] [Accepted: 05/30/2023] [Indexed: 06/09/2023]
Abstract
Carboxypeptidase E (CPE), an essential enzyme in the biosynthetic production line of most peptide hormones and neuropeptides, is predominantly expressed in endocrine tissues and in the nervous system. CPE is active in acidic environments where it cleaves the C'-terminal basic residues of peptide precursors to generate their bioactive form. Consequently, this highly conserved enzyme regulates numerous fundamental biological processes. Here, we combined live-cell microscopy and molecular analysis to examine the intracellular distribution and secretion dynamics of fluorescently tagged CPE. We show that, in non-endocrine cells, tagged-CPE is a soluble luminal protein that is efficiently exported from the ER via the Golgi apparatus to lysosomes. The C'-terminal conserved amphipathic helix serves as a lysosomal and secretory granule targeting and a secretion motif. Following secretion, CPE may be reinternalized into the lysosomes of neighboring cells.
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Affiliation(s)
- Shir Armoza-Eilat
- Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Yehonathan Malis
- Department of Pathology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Michal Caspi
- Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Olga Shomron
- Department of Pathology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Koret Hirschberg
- Department of Pathology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Rina Rosin-Arbesfeld
- Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
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48
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Musavinezhad M, Shkarin A, Rattenbacher D, Renger J, Utikal T, Götzinger S, Sandoghdar V. Quantum Efficiency of Single Dibenzoterrylene Molecules in p-Dichlorobenzene at Cryogenic Temperatures. J Phys Chem B 2023. [PMID: 37267598 DOI: 10.1021/acs.jpcb.3c01755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We measure the quantum efficiency (QE) of individual dibenzoterrylene (DBT) molecules embedded in p-dichlorobenzene at cryogenic temperatures. To achieve this, we combine two distinct methods based on the maximal photon emission and on the power required to saturate the zero-phonon line to compensate for uncertainties in some key system parameters. We find that the outcomes of the two approaches are in good agreement for reasonable values of the parameters involved, reporting a large fraction of molecules with QE values above 50%, with some exceeding 70%. Furthermore, we observe no correlation between the observed lower bound on the QE and the lifetime of the molecule, suggesting that most of the molecules have a QE exceeding the established lower bound. This confirms the suitability of DBT for quantum optics experiments. In light of previous reports of low QE values at ambient conditions, our results hint at the possibility of a strong temperature dependence of the QE.
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Affiliation(s)
- Mohammad Musavinezhad
- Max Planck Institute for the Science of Light, D-91058 Erlangen, Germany
- Department of Physics, Friedrich Alexander University Erlangen-Nuremberg, D-91058 Erlangen, Germany
| | - Alexey Shkarin
- Max Planck Institute for the Science of Light, D-91058 Erlangen, Germany
| | | | - Jan Renger
- Max Planck Institute for the Science of Light, D-91058 Erlangen, Germany
| | - Tobias Utikal
- Max Planck Institute for the Science of Light, D-91058 Erlangen, Germany
| | - Stephan Götzinger
- Max Planck Institute for the Science of Light, D-91058 Erlangen, Germany
- Department of Physics, Friedrich Alexander University Erlangen-Nuremberg, D-91058 Erlangen, Germany
- Graduate School in Advanced Optical Technologies (SAOT), Friedrich Alexander University Erlangen-Nuremberg, D-91052 Erlangen, Germany
| | - Vahid Sandoghdar
- Max Planck Institute for the Science of Light, D-91058 Erlangen, Germany
- Department of Physics, Friedrich Alexander University Erlangen-Nuremberg, D-91058 Erlangen, Germany
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49
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Weinstein JY, Martí-Gómez C, Lipsh-Sokolik R, Hoch SY, Liebermann D, Nevo R, Weissman H, Petrovich-Kopitman E, Margulies D, Ivankov D, McCandlish DM, Fleishman SJ. Designed active-site library reveals thousands of functional GFP variants. Nat Commun 2023; 14:2890. [PMID: 37210560 DOI: 10.1038/s41467-023-38099-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 04/13/2023] [Indexed: 05/22/2023] Open
Abstract
Mutations in a protein active site can lead to dramatic and useful changes in protein activity. The active site, however, is sensitive to mutations due to a high density of molecular interactions, substantially reducing the likelihood of obtaining functional multipoint mutants. We introduce an atomistic and machine-learning-based approach, called high-throughput Functional Libraries (htFuncLib), that designs a sequence space in which mutations form low-energy combinations that mitigate the risk of incompatible interactions. We apply htFuncLib to the GFP chromophore-binding pocket, and, using fluorescence readout, recover >16,000 unique designs encoding as many as eight active-site mutations. Many designs exhibit substantial and useful diversity in functional thermostability (up to 96 °C), fluorescence lifetime, and quantum yield. By eliminating incompatible active-site mutations, htFuncLib generates a large diversity of functional sequences. We envision that htFuncLib will be used in one-shot optimization of activity in enzymes, binders, and other proteins.
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Affiliation(s)
| | - Carlos Martí-Gómez
- Simons Center for Quantitative Biology, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, USA
| | - Rosalie Lipsh-Sokolik
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Shlomo Yakir Hoch
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Demian Liebermann
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Reinat Nevo
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Haim Weissman
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | | | - David Margulies
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Dmitry Ivankov
- Center of Life Sciences, Skolkovo Institute of Science and Technology, Moscow, Russia
| | - David M McCandlish
- Simons Center for Quantitative Biology, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, USA
| | - Sarel J Fleishman
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, 7610001, Israel.
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50
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Linghu C, An B, Shpokayte M, Celiker OT, Shmoel N, Zhang R, Zhang C, Park D, Park WM, Ramirez S, Boyden ES. Recording of cellular physiological histories along optically readable self-assembling protein chains. Nat Biotechnol 2023; 41:640-651. [PMID: 36593405 PMCID: PMC10188365 DOI: 10.1038/s41587-022-01586-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 10/21/2022] [Indexed: 01/03/2023]
Abstract
Observing cellular physiological histories is key to understanding normal and disease-related processes. Here we describe expression recording islands-a fully genetically encoded approach that enables both continual digital recording of biological information within cells and subsequent high-throughput readout in fixed cells. The information is stored in growing intracellular protein chains made of self-assembling subunits, human-designed filament-forming proteins bearing different epitope tags that each correspond to a different cellular state or function (for example, gene expression downstream of neural activity or pharmacological exposure), allowing the physiological history to be read out along the ordered subunits of protein chains with conventional optical microscopy. We use expression recording islands to record gene expression timecourse downstream of specific pharmacological and physiological stimuli in cultured neurons and in living mouse brain, with a time resolution of a fraction of a day, over periods of days to weeks.
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Affiliation(s)
- Changyang Linghu
- Brain and Cognitive Sciences, MIT, Cambridge, MA, USA
- Biological Engineering, MIT, Cambridge, MA, USA
- Media Arts and Sciences, MIT, Cambridge, MA, USA
- McGovern Institute, MIT, Cambridge, MA, USA
- Department of Cell and Developmental Biology, Program in Single Cell Spatial Analysis, and Michigan Neuroscience Institute, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Bobae An
- Brain and Cognitive Sciences, MIT, Cambridge, MA, USA
- Biological Engineering, MIT, Cambridge, MA, USA
- Media Arts and Sciences, MIT, Cambridge, MA, USA
- McGovern Institute, MIT, Cambridge, MA, USA
| | - Monika Shpokayte
- Graduate Program for Neuroscience, Boston University, Boston, MA, USA
- Psychological and Brain Sciences, Boston University, Boston, MA, USA
| | - Orhan T Celiker
- Brain and Cognitive Sciences, MIT, Cambridge, MA, USA
- Biological Engineering, MIT, Cambridge, MA, USA
- Media Arts and Sciences, MIT, Cambridge, MA, USA
- McGovern Institute, MIT, Cambridge, MA, USA
| | - Nava Shmoel
- Brain and Cognitive Sciences, MIT, Cambridge, MA, USA
- Biological Engineering, MIT, Cambridge, MA, USA
- Media Arts and Sciences, MIT, Cambridge, MA, USA
- McGovern Institute, MIT, Cambridge, MA, USA
| | - Ruihan Zhang
- Brain and Cognitive Sciences, MIT, Cambridge, MA, USA
- Biological Engineering, MIT, Cambridge, MA, USA
- Media Arts and Sciences, MIT, Cambridge, MA, USA
- McGovern Institute, MIT, Cambridge, MA, USA
| | - Chi Zhang
- Brain and Cognitive Sciences, MIT, Cambridge, MA, USA
- Biological Engineering, MIT, Cambridge, MA, USA
- Media Arts and Sciences, MIT, Cambridge, MA, USA
- McGovern Institute, MIT, Cambridge, MA, USA
| | - Demian Park
- Brain and Cognitive Sciences, MIT, Cambridge, MA, USA
- Biological Engineering, MIT, Cambridge, MA, USA
- Media Arts and Sciences, MIT, Cambridge, MA, USA
- McGovern Institute, MIT, Cambridge, MA, USA
| | - Won Min Park
- Chemical Engineering, Kansas State University, Manhattan, KS, USA
| | - Steve Ramirez
- Psychological and Brain Sciences, Boston University, Boston, MA, USA
| | - Edward S Boyden
- Brain and Cognitive Sciences, MIT, Cambridge, MA, USA.
- Biological Engineering, MIT, Cambridge, MA, USA.
- Media Arts and Sciences, MIT, Cambridge, MA, USA.
- McGovern Institute, MIT, Cambridge, MA, USA.
- Howard Hughes Medical Institute, MIT, Cambridge, MA, USA.
- K Lisa Yang Center for Bionics, MIT, Cambridge, MA, USA.
- Center for Neurobiological Engineering, MIT, Cambridge, MA, USA.
- Koch Institute, MIT, Cambridge, MA, USA.
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