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Subach OM, Piatkevich KD, Subach FV. Development of a genetically encoded NMT indicator for detection of mercury ions based on the green fluorescent protein mNeonGreen and metallothionein II from rat liver. Heliyon 2024; 10:e32814. [PMID: 38975119 PMCID: PMC11225830 DOI: 10.1016/j.heliyon.2024.e32814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2024] [Revised: 06/07/2024] [Accepted: 06/10/2024] [Indexed: 07/09/2024] Open
Abstract
Heavy metals, particularly mercury, rank as some of the most hazardous systemic toxicants known to cause multiple organ damage, even at lower levels of exposure. Its detection in the environment and in the live cells is an actual task. Here, we engineered a novel genetically encoded fluorescent NMT indicator for mercury ions by inserting the metallothionein II domain from rat liver into the bright green-yellow fluorescent protein mNeonGreen, followed by directed molecular evolution of the resulting sensor prototype in bacteria. In solution, the NMT indicator was 1.7-fold brighter than the standard eGFP fluorescent protein and responded to the addition of even 10-18-10-19 M mercury ions by quenching fluorescence with a 5-fold fluorescence response and extremely high affinity to mercury ions characterized by the K d value of 0.50 ± 0.05 aM. We also characterized the selectivity of the NMT indicator to other metal cations. In cultured mammalian cells, the NMT indicator detected even an extracellular concentration of 0.1 fM mercury ions and achieved a 5.9-fold change in ΔF/F fluorescence intensity.
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Affiliation(s)
- Oksana M. Subach
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, Moscow, 123182, Russia
| | - Kiryl D. Piatkevich
- School of Life Sciences, Westlake University, Hangzhou, 310024, China
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, 310024, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, 310024, China
| | - Fedor V. Subach
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, Moscow, 123182, Russia
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Hara Y, Ichiraku A, Matsuda T, Sakane A, Sasaki T, Nagai T, Horikawa K. High-affinity tuning of single fluorescent protein-type indicators by flexible linker length optimization in topology mutant. Commun Biol 2024; 7:705. [PMID: 38851844 PMCID: PMC11162441 DOI: 10.1038/s42003-024-06394-0] [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: 05/17/2023] [Accepted: 05/29/2024] [Indexed: 06/10/2024] Open
Abstract
Genetically encoded Ca2+ indicators (GECIs) are versatile for live imaging of cellular activities. Besides the brightness and dynamic range of signal change of GECIs, Ca2+ affinity is another critical parameter for successful Ca2+ imaging, as the concentration range of Ca2+ dynamics differs from low nanomolar to sub-millimolar depending on the celltype and organism. However, ultrahigh-affinity GECIs, particularly the single fluorescent protein (1FP)-type, are lacking. Here, we report a simple strategy that increases Ca2+ affinity through the linker length optimization in topology mutants of existing 1FP-type GECIs. The resulting ultrahigh-affinity GECIs, CaMPARI-nano, BGECO-nano, and RCaMP-nano (Kd = 17-25 nM), enable unique biological applications, including the detection of low nanomolar Ca2+ dynamics, highlighting active signaling cells, and multi-functional imaging with other second messengers. The linker length optimization in topology mutants could be applied to other 1FP-type indicators of glutamate and potassium, rendering it a widely applicable technique for modulating indicator affinity.
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Affiliation(s)
- Yusuke Hara
- Department of Optical Imaging, Advanced Research Promotion Center, Tokushima University, 3-18-15 Kuramoto, Tokushima, Tokushima, 770-8503, Japan
| | - Aya Ichiraku
- Department of Optical Imaging, Advanced Research Promotion Center, Tokushima University, 3-18-15 Kuramoto, Tokushima, Tokushima, 770-8503, Japan
| | - Tomoki Matsuda
- Department of Biomolecular Science and Engineering, SANKEN, Osaka University, Mihogaoka 8-1, Ibaraki, Osaka, 567-0047, Japan
| | - Ayuko Sakane
- Department of Biochemistry, Tokushima University Graduate School of Medicine, 3-18-15 Kuramoto, Tokushima, Tokushima, 770-8503, Japan
- Division of Interdisciplinary Researches for Medicine and Photonics, Institute of Post-LED Photonics (pLED), Tokushima University, 3-18-15 Kuramoto, Tokushima, Tokushima, 770-8503, Japan
| | - Takuya Sasaki
- Department of Biochemistry, Tokushima University Graduate School of Medicine, 3-18-15 Kuramoto, Tokushima, Tokushima, 770-8503, Japan
| | - Takeharu Nagai
- Department of Biomolecular Science and Engineering, SANKEN, Osaka University, Mihogaoka 8-1, Ibaraki, Osaka, 567-0047, Japan
- Institute for Open and Transdisciplinary Research Initiatives, Osaka University, Yamadaoka 2-1, Suita, Osaka, 565-0871, Japan
| | - Kazuki Horikawa
- Department of Optical Imaging, Advanced Research Promotion Center, Tokushima University, 3-18-15 Kuramoto, Tokushima, Tokushima, 770-8503, Japan.
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Jensen GC, Janis MK, Nguyen HN, David OW, Zastrow ML. Fluorescent Protein-Based Sensors for Detecting Essential Metal Ions across the Tree of Life. ACS Sens 2024; 9:1622-1643. [PMID: 38587931 PMCID: PMC11073808 DOI: 10.1021/acssensors.3c02695] [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] [Indexed: 04/10/2024]
Abstract
Genetically encoded fluorescent metal ion sensors are powerful tools for elucidating metal dynamics in living systems. Over the last 25 years since the first examples of genetically encoded fluorescent protein-based calcium indicators, this toolbox of probes has expanded to include other essential and non-essential metal ions. Collectively, these tools have illuminated fundamental aspects of metal homeostasis and trafficking that are crucial to fields ranging from neurobiology to human nutrition. Despite these advances, much of the application of metal ion sensors remains limited to mammalian cells and tissues and a limited number of essential metals. Applications beyond mammalian systems and in vivo applications in living organisms have primarily used genetically encoded calcium ion sensors. The aim of this Perspective is to provide, with the support of historical and recent literature, an updated and critical view of the design and use of fluorescent protein-based sensors for detecting essential metal ions in various organisms. We highlight the historical progress and achievements with calcium sensors and discuss more recent advances and opportunities for the detection of other essential metal ions. We also discuss outstanding challenges in the field and directions for future studies, including detecting a wider variety of metal ions, developing and implementing a broader spectral range of sensors for multiplexing experiments, and applying sensors to a wider range of single- and multi-species biological systems.
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Affiliation(s)
- Gary C Jensen
- Department of Chemistry, University of Houston, Houston, Texas 77204, United States
| | - Makena K Janis
- Department of Chemistry, University of Houston, Houston, Texas 77204, United States
| | - Hazel N Nguyen
- Department of Chemistry, University of Houston, Houston, Texas 77204, United States
| | - Ogonna W David
- Department of Chemistry, University of Houston, Houston, Texas 77204, United States
| | - Melissa L Zastrow
- Department of Chemistry, University of Houston, Houston, Texas 77204, United States
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4
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Aggarwal A, Sunil S, Bendifallah I, Moon M, Drobizhev M, Zarowny L, Zheng J, Wu SY, Lohman AW, Tebo AG, Emiliani V, Podgorski K, Shen Y, Campbell RE. Blue-shifted genetically encoded Ca 2+ indicator with enhanced two-photon absorption. NEUROPHOTONICS 2024; 11:024207. [PMID: 38577628 PMCID: PMC10993905 DOI: 10.1117/1.nph.11.2.024207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 03/04/2024] [Accepted: 03/06/2024] [Indexed: 04/06/2024]
Abstract
Significance Genetically encoded calcium ion (Ca 2 + ) indicators (GECIs) are powerful tools for monitoring intracellular Ca 2 + concentration changes in living cells and model organisms. In particular, GECIs have found particular utility for monitoring the transient increase of Ca 2 + concentration that is associated with the neuronal action potential. However, the palette of highly optimized GECIs for imaging of neuronal activity remains relatively limited. Expanding the selection of available GECIs to include new colors and distinct photophysical properties could create new opportunities for in vitro and in vivo fluorescence imaging of neuronal activity. In particular, blue-shifted variants of GECIs are expected to have enhanced two-photon brightness, which would facilitate multiphoton microscopy. Aim We describe the development and applications of T-GECO1-a high-performance blue-shifted GECI based on the Clavularia sp.-derived mTFP1. Approach We use protein engineering and extensive directed evolution to develop T-GECO1. We characterize the purified protein and assess its performance in vitro using one-photon excitation in cultured rat hippocampal neurons, in vivo using one-photon excitation fiber photometry in mice, and ex vivo using two-photon Ca 2 + imaging in hippocampal slices. Results The Ca 2 + -bound state of T-GECO1 has an excitation peak maximum of 468 nm, an emission peak maximum of 500 nm, an extinction coefficient of 49,300 M - 1 cm - 1 , a quantum yield of 0.83, and two-photon brightness approximately double that of EGFP. The Ca 2 + -dependent fluorescence increase is 15-fold, and the apparent K d for Ca 2 + is 82 nM. With two-photon excitation conditions at 850 nm, T-GECO1 consistently enabled the detection of action potentials with higher signal-to-noise (SNR) than a late generation GCaMP variant. Conclusions T-GECO1 is a high-performance blue-shifted GECI that, under two-photon excitation conditions, provides advantages relative to late generation GCaMP variants.
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Affiliation(s)
- Abhi Aggarwal
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
- Allen Institute for Neural Dynamics, Seattle, Washington, United States
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia, United States
- University of Calgary, Hotchkiss Brain Institute, Department of Cell Biology and Anatomy Calgary, Alberta, Canada
| | - Smrithi Sunil
- Allen Institute for Neural Dynamics, Seattle, Washington, United States
| | | | - Michael Moon
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
| | - Mikhail Drobizhev
- Montana State University, Department of Microbiology and Cell Biology, Bozeman, Montana, United States
| | - Landon Zarowny
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
| | - Jihong Zheng
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia, United States
| | - Sheng-Yi Wu
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
| | - Alexander W. Lohman
- University of Calgary, Hotchkiss Brain Institute, Department of Cell Biology and Anatomy Calgary, Alberta, Canada
| | - Alison G. Tebo
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia, United States
| | | | - Kaspar Podgorski
- Allen Institute for Neural Dynamics, Seattle, Washington, United States
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia, United States
| | - Yi Shen
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
| | - Robert E. Campbell
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
- Université Laval, CERVO Brain Research Center, Department of Biochemistry, Microbiology, and Bioinformatics, Québec, Québec, Canada
- University of Tokyo, Department of Chemistry, Tokyo, Japan
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Chen Y, Pang S, Li J, Lu Y, Gao C, Xiao Y, Chen M, Wang M, Ren X. Genetically encoded protein sensors for metal ion detection in biological systems: a review and bibliometric analysis. Analyst 2023; 148:5564-5581. [PMID: 37872814 DOI: 10.1039/d3an01412f] [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: 10/25/2023]
Abstract
Metal ions are indispensable elements in living organisms and are associated with regulating various biological processes. An imbalance in metal ion content can lead to disorders in normal physiological functions of the human body and cause various diseases. Genetically encoded fluorescent protein sensors have the advantages of low biotoxicity, high specificity, and a long imaging time in vivo and have become a powerful tool to visualize or quantify the concentration level of biomolecules in vivo and in vitro, temporal and spatial distribution, and life activity process. This review analyzes the development status and current research hotspots in the field of genetically encoded fluorescent protein sensors by bibliometric analysis. Based on the results of bibliometric analysis, the research progress of genetically encoded fluorescent protein sensors for metal ion detection is reviewed, and the construction strategies, physicochemical properties, and applications of such sensors in biological imaging are summarized.
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Affiliation(s)
- Yuxueyuan Chen
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin 300381, China
- College of Chinese Materia Medica, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, China
| | - ShuChao Pang
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin 300381, China
| | - Jingya Li
- College of Chinese Materia Medica, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, China
| | - Yun Lu
- College of Chinese Materia Medica, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, China
| | - Chenxia Gao
- College of Chinese Materia Medica, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, China
| | - Yanyu Xiao
- College of Chinese Materia Medica, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, China
| | - Meiling Chen
- College of Chinese Materia Medica, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, China
- Tianjin Key Laboratory of Therapeutic Substance of Traditional Chinese Medicine, Tianjin 301617, China.
| | - Meng Wang
- State Key Laboratory of Component-based Chinese Medicine, Tianjin 301617, China
| | - Xiaoliang Ren
- College of Chinese Materia Medica, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, China
- Tianjin Key Laboratory of Therapeutic Substance of Traditional Chinese Medicine, Tianjin 301617, China.
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Subach OM, Vlaskina AV, Agapova YK, Nikolaeva AY, Varizhuk AM, Podgorny OV, Piatkevich KD, Patrushev MV, Boyko KM, Subach FV. YTnC2, an improved genetically encoded green calcium indicator based on toadfish troponin C. FEBS Open Bio 2023; 13:2047-2060. [PMID: 37650870 PMCID: PMC10626279 DOI: 10.1002/2211-5463.13702] [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: 06/01/2023] [Revised: 08/03/2023] [Accepted: 08/30/2023] [Indexed: 09/01/2023] Open
Abstract
Genetically encoded calcium indicators based on truncated troponin C are attractive probes for calcium imaging due to their relatively small molecular size and twofold reduced calcium ion buffering. However, the best-suited members of this family, YTnC and cNTnC, suffer from low molecular brightness, limited dynamic range, and/or poor sensitivity to calcium transients in neurons. To overcome these limitations, we developed an enhanced version of YTnC, named YTnC2. Compared with YTnC, YTnC2 had 5.7-fold higher molecular brightness and 6.4-fold increased dynamic range in vitro. YTnC2 was successfully used to reveal calcium transients in the cytosol and in the lumen of mitochondria of both mammalian cells and cultured neurons. Finally, we obtained and analyzed the crystal structure of the fluorescent domain of the YTnC2 mutant.
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Affiliation(s)
- Oksana M. Subach
- Complex of NBICS TechnologiesNational Research Center “Kurchatov Institute”MoscowRussia
| | - Anna V. Vlaskina
- Complex of NBICS TechnologiesNational Research Center “Kurchatov Institute”MoscowRussia
| | - Yulia K. Agapova
- Complex of NBICS TechnologiesNational Research Center “Kurchatov Institute”MoscowRussia
| | - Alena Y. Nikolaeva
- Complex of NBICS TechnologiesNational Research Center “Kurchatov Institute”MoscowRussia
- Bach Institute of BiochemistryResearch Centre of Biotechnology of the Russian Academy of SciencesMoscowRussia
| | - Anna M. Varizhuk
- Federal Research and Clinical Center of Physical‐Chemical Medicine of Federal Medical Biological AgencyMoscowRussia
- Moscow Institute of Physics and TechnologyDolgoprudnyRussia
| | - Oleg V. Podgorny
- M.M. Shemyakin and Yu.A. Ovchinnikov Institute of Bioorganic ChemistryRASMoscowRussia
- Center for Precision Genome Editing and Genetic Technologies for BiomedicinePirogov Russian National Research Medical UniversityMoscowRussia
- Federal Center of Brain Research and Neurotechnologies of Federal Medical Biological AgencyMoscowRussia
| | - Kiryl D. Piatkevich
- School of Life SciencesWestlake UniversityHangzhouChina
- Westlake Laboratory of Life Sciences and BiomedicineHangzhouChina
| | - Maxim V. Patrushev
- Complex of NBICS TechnologiesNational Research Center “Kurchatov Institute”MoscowRussia
| | - Konstantin M. Boyko
- Bach Institute of BiochemistryResearch Centre of Biotechnology of the Russian Academy of SciencesMoscowRussia
| | - Fedor V. Subach
- Complex of NBICS TechnologiesNational Research Center “Kurchatov Institute”MoscowRussia
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7
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Aggarwal A, Sunil S, Bendifallah I, Moon M, Drobizhev M, Zarowny L, Zheng J, Wu SY, Lohman AW, Tebo AG, Emiliani V, Podgorski K, Shen Y, Campbell RE. A blue-shifted genetically encoded Ca 2+ indicator with enhanced two-photon absorption. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.12.562058. [PMID: 37905143 PMCID: PMC10614751 DOI: 10.1101/2023.10.12.562058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
Significance Genetically encoded calcium ion (Ca2+) indicators (GECIs) are powerful tools for monitoring intracellular Ca2+ concentration changes in living cells and model organisms. In particular, GECIs have found particular utility for monitoring the transient increase of Ca2+ concentration that is associated with the neuronal action potential. However, the palette of highly optimized GECIs for imaging of neuronal activity remains relatively limited. Expanding the selection of available GECIs to include new colors and distinct photophysical properties could create new opportunities for in vitro and in vivo fluorescence imaging of neuronal activity. In particular, blue-shifted variants of GECIs are expected to have enhanced two-photon brightness, which would facilitate multiphoton microscopy. Aim We describe the development and applications of T-GECO1 - a high-performance blue-shifted GECI based on the Clavularia sp.-derived mTFP1. Approach We used protein engineering and extensive directed evolution to develop T-GECO1. We characterize the purified protein and assess its performance in vitro using one-photon excitation in cultured rat hippocampal neurons, in vivo using one-photon excitation fiber photometry in mice, and ex vivo using two-photon Ca2+ imaging in hippocampal slices. Results The Ca2+-bound state of T-GECO1 has an excitation peak maximum of 468 nm, an emission peak maximum of 500 nm, an extinction coefficient of 49,300 M-1cm-1, a quantum yield of 0.83, and two-photon brightness approximately double that of EGFP. The Ca2+-dependent fluorescence increase is 15-fold and the apparent Kd for Ca2+ is 82 nM. With two-photon excitation conditions at 850 nm, T-GECO1 consistently enabled detection of action potentials with higher signal-to-noise (SNR) than a late generation GCaMP variant. Conclusion T-GECO1 is a high performance blue-shifted GECI that, under two-photon excitation conditions, provides advantages relative to late generation GCaMP variants.
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Affiliation(s)
- Abhi Aggarwal
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
- Allen Institute for Neural Dynamics, Seattle, Washington, United States of America
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia, United States of America
- University of Calgary, Department of Cell Biology and Anatomy and Hotchkiss Brain Institute, Calgary, Alberta, Canada
| | - Smrithi Sunil
- Allen Institute for Neural Dynamics, Seattle, Washington, United States of America
| | | | - Michael Moon
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
| | - Mikhail Drobizhev
- Montana State University, Department of Microbiology and Cell Biology, Bozeman, Montana, United States of America
| | - Landon Zarowny
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
| | - Jihong Zheng
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia, United States of America
| | - Sheng-Yi Wu
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
| | - Alexander W. Lohman
- University of Calgary, Department of Cell Biology and Anatomy and Hotchkiss Brain Institute, Calgary, Alberta, Canada
| | - Alison G. Tebo
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia, United States of America
| | | | - Kaspar Podgorski
- Allen Institute for Neural Dynamics, Seattle, Washington, United States of America
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia, United States of America
| | - Yi Shen
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
| | - Robert E. Campbell
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
- Université Laval, CERVO Brain Research Center and Department of Biochemistry, Microbiology, and Bioinformatics, Québec, Québec, Canada
- The University of Tokyo, Department of Chemistry, Bunkyo-ku, Tokyo, Japan
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Chai F, Cheng D, Nasu Y, Terai T, Campbell RE. Maximizing the performance of protein-based fluorescent biosensors. Biochem Soc Trans 2023; 51:1585-1595. [PMID: 37431791 PMCID: PMC10586770 DOI: 10.1042/bst20221413] [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: 05/01/2023] [Revised: 06/22/2023] [Accepted: 06/26/2023] [Indexed: 07/12/2023]
Abstract
Fluorescent protein (FP)-based biosensors are genetically encoded tools that enable the imaging of biological processes in the context of cells, tissues, or live animals. Though widely used in biological research, practically all existing biosensors are far from ideal in terms of their performance, properties, and applicability for multiplexed imaging. These limitations have inspired researchers to explore an increasing number of innovative and creative ways to improve and maximize biosensor performance. Such strategies include new molecular biology methods to develop promising biosensor prototypes, high throughput microfluidics-based directed evolution screening strategies, and improved ways to perform multiplexed imaging. Yet another approach is to effectively replace components of biosensors with self-labeling proteins, such as HaloTag, that enable the biocompatible incorporation of synthetic fluorophores or other ligands in cells or tissues. This mini-review will summarize and highlight recent innovations and strategies for enhancing the performance of FP-based biosensors for multiplexed imaging to advance the frontiers of research.
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Affiliation(s)
- Fu Chai
- Department of Chemistry, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan
| | - Dazhou Cheng
- Department of Chemistry, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan
| | - Yusuke Nasu
- Department of Chemistry, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan
- PRESTO, Japan Science and Technology Agency, Chiyoda-ku, Tokyo 102-0075, Japan
| | - Takuya Terai
- Department of Chemistry, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan
| | - Robert E. Campbell
- Department of Chemistry, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
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9
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Tran O, Hughes HJ, Carter T, Török K. Development and characterization of novel jGCaMP8f calcium sensor variants with improved kinetics and fluorescence response range. Front Cell Neurosci 2023; 17:1155406. [PMID: 37275778 PMCID: PMC10234427 DOI: 10.3389/fncel.2023.1155406] [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: 01/31/2023] [Accepted: 04/28/2023] [Indexed: 06/07/2023] Open
Abstract
Introduction Genetically encoded biosensors for monitoring intracellular calcium changes have advanced our understanding of cell signaling and neuronal activity patterns in health and disease. Successful application of GCaMP biosensors to a wide range of biological questions requires that sensor properties such as brightness and dynamic range, ligand affinity and response kinetics be tuned to the specific conditions or phenomena to be investigated. Random as well as rational targeted mutations of such sensor molecules have led to a number of important breakthroughs in this field, including the calcium sensors GCaMP6f and GCaMP6fu. jGCaMP8f of the most recently developed generation is promising a step-change in in vivo imaging with further increased fluorescence dynamic range. Here, we critically examine the biophysical properties of jGCaMP8f and report development by rational design of two novel variants of jGCaMP8f. Methods We determined the in vitro biophysical properties of jGCaMP8f and selected variants by fluorescence spectroscopies and compared their performance monitoring intracellular Ca2+ transients with previously developed fast and bright GCaMP sensors by live cell imaging. Results We demonstrate that the physiologically highly relevant Mg2+ not only majorly affects the kinetic responses of GCaMPs but also their brightness and fluorescence dynamic range. We developed novel variants jGCaMP8f L27A which has threefold faster off-kinetics and jGCaMP8f F366H which shows a ∼3-fold greater dynamic range than jGCaMP8f, in vitro as well as in HEK293T cells and endothelial cell line HUVEC in response to ATP stimulation. Discussion We discuss the importance of optimization of biosensors for studying neurobiology in the context of the novel variants of jGCaMP8f. The jGCaMP8f F366H variant with a large dynamic range has the potential to improve in vivo imaging outcomes with increased signal-to-noise ratio. The L27A variant with faster kinetics than jGCaMP8f has larger cellular responses than previous fast GCaMP variants. The jGCaMP8f generation and novel improved variants presented here will further increase the application potential of GECIs in health and disease.
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Subach OM, Varfolomeeva L, Vlaskina AV, Agapova YK, Nikolaeva AY, Piatkevich KD, Patrushev MV, Boyko KM, Subach FV. FNCaMP, ratiometric green calcium indicator based on mNeonGreen protein. Biochem Biophys Res Commun 2023; 665:169-177. [PMID: 37163937 DOI: 10.1016/j.bbrc.2023.04.108] [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: 04/18/2023] [Revised: 04/28/2023] [Accepted: 04/28/2023] [Indexed: 05/12/2023]
Abstract
Neurobiologists widely use green genetically encoded calcium indicators (GECIs) for visualization of neuronal activity. Among them, ratiometric GECIs allow imaging of both active and non-active neuronal populations. However, they are not popular, since their properties are inferior to intensiometric GCaMP series of GECIs. The most characterized and developed ratiometric green GECI is FGCaMP7. However, the dynamic range and sensitivity of its large Stock's shift green (LSS-Green) form is significantly lower than its Green form and its molecular design is not optimal. To address these drawbacks, we engineered a ratiometric green calcium indicator, called FNCaMP, which is based on bright mNeonGreen protein and calmodulin from A. niger and has optimal NTnC-like design. We compared the properties of the FNCaMP and FGCaMP7 indicators in vitro, in mammalian cells, and in neuronal cultures. Finally, we obtained and analyzed X-ray structure of the FNCaMP indicator.
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Affiliation(s)
- Oksana M Subach
- Complex of NBICS Technologies, National Research Center "Kurchatov Institute", Moscow, 123182, Russia.
| | - Larisa Varfolomeeva
- Bach Institute of Biochemistry, Research Centre of Biotechnology of the Russian Academy of Sciences, Moscow, 119071, Russia.
| | - Anna V Vlaskina
- Complex of NBICS Technologies, National Research Center "Kurchatov Institute", Moscow, 123182, Russia.
| | - Yulia K Agapova
- Complex of NBICS Technologies, National Research Center "Kurchatov Institute", Moscow, 123182, Russia.
| | - Alena Y Nikolaeva
- Complex of NBICS Technologies, National Research Center "Kurchatov Institute", Moscow, 123182, Russia; Bach Institute of Biochemistry, Research Centre of Biotechnology of the Russian Academy of Sciences, Moscow, 119071, Russia.
| | - Kiryl D Piatkevich
- School of Life Sciences, Westlake University, Hangzhou, 310024, China; Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, 310024, China; Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, 310024, China.
| | - Maxim V Patrushev
- Complex of NBICS Technologies, National Research Center "Kurchatov Institute", Moscow, 123182, Russia.
| | - Konstantin M Boyko
- Bach Institute of Biochemistry, Research Centre of Biotechnology of the Russian Academy of Sciences, Moscow, 119071, Russia.
| | - Fedor V Subach
- Complex of NBICS Technologies, National Research Center "Kurchatov Institute", Moscow, 123182, Russia.
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11
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Li J, Shang Z, Chen JH, Gu W, Yao L, Yang X, Sun X, Wang L, Wang T, Liu S, Li J, Hou T, Xing D, Gill DL, Li J, Wang SQ, Hou L, Zhou Y, Tang AH, Zhang X, Wang Y. Engineering of NEMO as calcium indicators with large dynamics and high sensitivity. Nat Methods 2023:10.1038/s41592-023-01852-9. [PMID: 37081094 DOI: 10.1038/s41592-023-01852-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 03/16/2023] [Indexed: 04/22/2023]
Abstract
Genetically encoded calcium indicators (GECIs) are indispensable tools for real-time monitoring of intracellular calcium signals and cellular activities in living organisms. Current GECIs face the challenge of suboptimal peak signal-to-baseline ratio (SBR) with limited resolution for reporting subtle calcium transients. We report herein the development of a suite of calcium sensors, designated NEMO, with fast kinetics and wide dynamic ranges (>100-fold). NEMO indicators report Ca2+ transients with peak SBRs around 20-fold larger than the top-of-the-range GCaMP6 series. NEMO sensors further enable the quantification of absolution calcium concentration with ratiometric or photochromic imaging. Compared with GCaMP6s, NEMOs could detect single action potentials in neurons with a peak SBR two times higher and a median peak SBR four times larger in vivo, thereby outperforming most existing state-of-the-art GECIs. Given their high sensitivity and resolution to report intracellular Ca2+ signals, NEMO sensors may find broad applications in monitoring neuronal activities and other Ca2+-modulated physiological processes in both mammals and plants.
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Affiliation(s)
- Jia Li
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, China
| | - Ziwei Shang
- State Key Laboratory of Cognitive Neuroscience and Learning, IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China
| | - Jia-Hui Chen
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Brain Function and Disease, and Ministry of Education Key Laboratory for Membraneless Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
| | - Wenjia Gu
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, China
| | - Li Yao
- State Key Laboratory of Cognitive Neuroscience and Learning, IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China
| | - Xin Yang
- Exercise Physiology and Neurobiology Laboratory, College of PE and Sports, Beijing Normal University, Beijing, China
| | - Xiaowen Sun
- State Key Laboratory of Cognitive Neuroscience and Learning, IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China
| | - Liuqing Wang
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, China
| | - Tianlu Wang
- Institute of Biosciences and Technology, Texas A&M University, Houston, TX, USA
| | - Siyao Liu
- Institute of Biosciences and Technology, Texas A&M University, Houston, TX, USA
| | - Jiajing Li
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, China
| | - Tingting Hou
- State Key Laboratory of Membrane Biology College of Life Sciences, Peking University, Beijing, China
| | - Dajun Xing
- State Key Laboratory of Cognitive Neuroscience and Learning, IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China
| | - Donald L Gill
- Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey, PA, USA
| | - Jiejie Li
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, China
| | - Shi-Qiang Wang
- State Key Laboratory of Membrane Biology College of Life Sciences, Peking University, Beijing, China
| | - Lijuan Hou
- Exercise Physiology and Neurobiology Laboratory, College of PE and Sports, Beijing Normal University, Beijing, China
| | - Yubin Zhou
- Institute of Biosciences and Technology, Texas A&M University, Houston, TX, USA.
- Department of Translational Medical Sciences, School of Medicine, Texas A&M University, Houston, TX, USA.
| | - Ai-Hui Tang
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Brain Function and Disease, and Ministry of Education Key Laboratory for Membraneless Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China.
- Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei, China.
| | - Xiaohui Zhang
- State Key Laboratory of Cognitive Neuroscience and Learning, IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.
| | - Youjun Wang
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, China.
- Key Laboratory of Cell Proliferation and Regulation Biology, Ministry of Education, College of Life Sciences, Beijing Normal University, Beijing, China.
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12
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Krueger TD, Tang L, Fang C. Delineating Ultrafast Structural Dynamics of a Green-Red Fluorescent Protein for Calcium Sensing. BIOSENSORS 2023; 13:bios13020218. [PMID: 36831983 PMCID: PMC9954042 DOI: 10.3390/bios13020218] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/27/2023] [Accepted: 01/30/2023] [Indexed: 05/14/2023]
Abstract
Fluorescent proteins (FPs) are indispensable tools for noninvasive bioimaging and sensing. Measuring the free cellular calcium (Ca2+) concentrations in vivo with genetically encodable FPs can be a relatively direct measure of neuronal activity due to the complex signaling role of these ions. REX-GECO1 is a recently developed red-green emission and excitation ratiometric FP-based biosensor that achieves a high dynamic range due to differences in the chromophore response to light excitation with and without calcium ions. Using steady-state electronic measurements (UV/Visible absorption and emission), along with time-resolved spectroscopic techniques including femtosecond transient absorption (fs-TA) and femtosecond stimulated Raman spectroscopy (FSRS), the potential energy surfaces of these unique biosensors are unveiled with vivid details. The ground-state structural characterization of the Ca2+-free biosensor via FSRS reveals a more spacious protein pocket that allows the chromophore to efficiently twist and reach a dark state. In contrast, the more compressed cavity within the Ca2+-bound biosensor results in a more heterogeneous distribution of chromophore populations that results in multi-step excited state proton transfer (ESPT) pathways on the sub-140 fs, 600 fs, and 3 ps timescales. These results enable rational design strategies to enlarge the spectral separation between the protonated/deprotonated forms and the Stokes shift leading to a larger dynamic range and potentially higher fluorescence quantum yield, which should be broadly applicable to the calcium imaging and biosensor communities.
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13
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Subach OM, Vlaskina AV, Agapova YK, Korzhenevskiy DA, Nikolaeva AY, Varizhuk AM, Subach MF, Patrushev MV, Piatkevich KD, Boyko KM, Subach FV. cNTnC and fYTnC2, Genetically Encoded Green Calcium Indicators Based on Troponin C from Fast Animals. Int J Mol Sci 2022; 23:ijms232314614. [PMID: 36498942 PMCID: PMC9741049 DOI: 10.3390/ijms232314614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 11/19/2022] [Accepted: 11/21/2022] [Indexed: 11/24/2022] Open
Abstract
NTnC-like green fluorescent genetically encoded calcium indicators (GECIs) with two calcium ion binding sites were constructed using the insertion of truncated troponin C (TnC) from Opsanus tau into green fluorescent proteins (GFPs). These GECIs are small proteins containing the N- and C-termini of GFP; they exert a limited effect on the cellular free calcium ion concentration; and in contrast to calmodulin-based calcium indicators they lack undesired interactions with intracellular proteins in neurons. The available TnC-based NTnC or YTnC GECIs had either an inverted response and high brightness but a limited dynamic range or a positive response and fast kinetics in neurons but lower brightness and an enhanced but still limited dF/F dynamic range. Here, we solved the crystal structure of NTnC at 2.5 Å resolution. Based on this structure, we developed positive NTnC2 and inverted iNTnC2 GECIs with a large dF/F dynamic range in vitro but very slow rise and decay kinetics in neurons. To overcome their slow responsiveness, we swapped TnC from O. tau in NTnC2 with truncated troponin C proteins from the muscles of fast animals, namely, the falcon, hummingbird, cheetah, bat, rattlesnake, and ant, and then optimized the resulting constructs using directed molecular evolution. Characterization of the engineered variants using purified proteins, mammalian cells, and neuronal cultures revealed cNTnC GECI with truncated TnC from Calypte anna (hummingbird) to have the largest dF/F fluorescence response and fast dissociation kinetics in neuronal cultures. In addition, based on the insertion of truncated TnCs from fast animals into YTnC2, we developed fYTnC2 GECI with TnC from Falco peregrinus (falcon). The purified proteins cNTnC and fYTnC2 had 8- and 6-fold higher molecular brightness and 7- and 6-fold larger dF/F responses to the increase in Ca2+ ion concentration than YTnC, respectively. cNTnC GECI was also 4-fold more photostable than YTnC and fYTnC2 GECIs. Finally, we assessed the developed GECIs in primary mouse neuronal cultures stimulated with an external electric field; in these conditions, cNTnC had a 2.4-fold higher dF/F fluorescence response than YTnC and fYTnC2 and was the same or slightly slower (1.4-fold) than fYTnC2 and YTnC in the rise and decay half-times, respectively.
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Affiliation(s)
- Oksana M. Subach
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, Moscow 123182, Russia
| | - Anna V. Vlaskina
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, Moscow 123182, Russia
| | - Yuliya K. Agapova
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, Moscow 123182, Russia
| | - Dmitriy A. Korzhenevskiy
- Laboratory of Electrophysiology, Federal Center of Brain Research and Neurotechnologies, Ostrovityanova Str. 1, Bld. 10, Moscow 125367, Russia
| | - Alena Y. Nikolaeva
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, Moscow 123182, Russia
| | - Anna M. Varizhuk
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Malaya Pirogovskaya Str. 1a, Moscow 119435, Russia
- Moscow Institute of Physics and Technology, Dolgoprudny 141701, Russia
| | - Maksim F. Subach
- Department of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Maxim V. Patrushev
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, Moscow 123182, Russia
| | - Kiryl D. Piatkevich
- School of Life Sciences, Westlake University, Hangzhou 310024, China
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou 310024, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou 310024, China
| | - Konstantin M. Boyko
- Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Leninsky Ave. 33, Bld. 2, Moscow 119071, Russia
| | - Fedor V. Subach
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, Moscow 123182, Russia
- Correspondence: ; Tel.: +7-499-196-7100-3389
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14
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Pochechuev MS, Fedotov IV, Martynov GN, Solotenkov MA, Ivashkina OI, Rogozhnikova OS, Fedotov AB, Anokhin KV, Zheltikov AM. Implantable graded-index fibers for neural-dynamics-resolving brain imaging in awake mice on an air-lifted platform. JOURNAL OF BIOPHOTONICS 2022; 15:e202200025. [PMID: 35666011 DOI: 10.1002/jbio.202200025] [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: 02/01/2022] [Revised: 05/13/2022] [Accepted: 05/14/2022] [Indexed: 06/15/2023]
Abstract
We demonstrate a versatile framework for cellular brain imaging in awake mice based on suitably tailored segments of graded-index (GRIN) fiber. Closed-form solutions to ray-path equations for graded-index waveguides are shown to offer important insights into image-transmission properties of GRIN fibers, suggesting useful recipes for optimized GRIN-fiber-based deep-brain imaging. We show that the lengths of GRIN imaging components intended for deep-brain studies in freely moving rodents need to be chosen as a tradeoff among the spatial resolution, the targeted imaging depth and the degree of fiber-probe invasiveness. In the experimental setting that we present in this paper, the head of an awake mouse with a GRIN-fiber implant is fixed under a microscope objective, but the mouse is free to move around an in-house-built flat-floored air-lifted platform, exploring a predesigned environment, configured as an arena for one of standard cognitive tests. We show that cellular-resolution deep-brain imaging can be integrated in this setting with robust cell-specific optical neural recording to enable in vivo studies with minimal physical restraints on animal models. The enhancement of the information capacity of the fluorescence signal, achieved via a suitable filtering of the GRIN-fiber readout, is shown to open routes toward practical imaging modalities whereby the deep-brain neuronal dynamics and axonal connections underpinning the integrative functions of essential brain structures can be studied in awake rodent models.
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Affiliation(s)
| | - Ilya V Fedotov
- Physics Department, M.V. Lomonosov Moscow State University, Moscow, Russia
- Department of Physics and Astronomy, IQSE, Texas A&M University, College Station, Texas, USA
- Russian Quantum Center, Skolkovo, Moscow, Russia
| | | | - Maxim A Solotenkov
- Physics Department, M.V. Lomonosov Moscow State University, Moscow, Russia
| | - Olga I Ivashkina
- Institute for Advanced Brain Studies, M.V. Lomonosov Moscow State University, Moscow, Russia
- National Research Center "Kurchatov Institute", Moscow, Russia
- P.K. Anokhin Research Institute of Normal Physiology, Moscow, Russia
| | - Olga S Rogozhnikova
- Institute for Advanced Brain Studies, M.V. Lomonosov Moscow State University, Moscow, Russia
| | - Andrei B Fedotov
- Physics Department, M.V. Lomonosov Moscow State University, Moscow, Russia
- Russian Quantum Center, Skolkovo, Moscow, Russia
- National University of Science and Technology "MISiS,", Moscow, Russia
| | - Konstantin V Anokhin
- Institute for Advanced Brain Studies, M.V. Lomonosov Moscow State University, Moscow, Russia
- P.K. Anokhin Research Institute of Normal Physiology, Moscow, Russia
| | - Aleksei M Zheltikov
- Department of Physics and Astronomy, IQSE, Texas A&M University, College Station, Texas, USA
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15
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Torres Cabán C, Yang M, Lai C, Yang L, Subach FV, Smith BO, Piatkevich KD, Boyden ES. Tuning the Sensitivity of Genetically Encoded Fluorescent Potassium Indicators through Structure-Guided and Genome Mining Strategies. ACS Sens 2022; 7:1336-1346. [PMID: 35427452 PMCID: PMC9150168 DOI: 10.1021/acssensors.1c02201] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Accepted: 03/09/2022] [Indexed: 12/31/2022]
Abstract
Genetically encoded potassium indicators lack optimal binding affinity for monitoring intracellular dynamics in mammalian cells. Through structure-guided design and genome mining of potassium binding proteins, we developed green fluorescent potassium indicators with a broad range of binding affinities. KRaION1 (K+ ratiometric indicator for optical imaging based on mNeonGreen 1), based on the insertion of a potassium binding protein, Kbp, from E. coli (Ec-Kbp) into the fluorescent protein mNeonGreen, exhibits an isotonically measured Kd of 69 ± 10 mM (mean ± standard deviation used throughout). We identified Ec-Kbp's binding site using NMR spectroscopy to detect protein-thallium scalar couplings and refined the structure of Ec-Kbp in its potassium-bound state. Guided by this structure, we modified KRaION1, yielding KRaION1/D9N and KRaION2, which exhibit isotonically measured Kd's of 138 ± 21 and 96 ± 9 mM. We identified four Ec-Kbp homologues as potassium binding proteins, which yielded indicators with isotonically measured binding affinities in the 39-112 mM range. KRaIONs functioned in HeLa cells, but the Kd values differed from the isotonically measured case. We found that, by tuning the experimental conditions, Kd values could be obtained that were consistent in vitro and in vivo. We thus recommend characterizing potassium indicator Kd in the physiological context of interest before application.
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Affiliation(s)
- Cristina
C. Torres Cabán
- McGovern
Institute for Brain Research, MIT, Cambridge, Massachusetts 02139, United States
- Department
of Biological Engineering, MIT, Cambridge, Massachusetts 02139, United States
- Department
of Media Arts & Sciences, MIT, Cambridge, Massachusetts 02139, United States
| | - Minghan Yang
- School
of Life Sciences, Westlake University, Hangzhou, Zhejiang 310024, China
- Westlake
Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang 310024, China
- Institute
of Basic Medical Sciences, Westlake Institute
for Advanced Study, Hangzhou, Zhejiang 310024, China
- College
of Physics, Jilin University, Changchun, Jilin 130012, China
| | - Cuixin Lai
- School
of Life Sciences, Westlake University, Hangzhou, Zhejiang 310024, China
- Westlake
Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang 310024, China
- Institute
of Basic Medical Sciences, Westlake Institute
for Advanced Study, Hangzhou, Zhejiang 310024, China
| | - Lina Yang
- School
of Life Sciences, Westlake University, Hangzhou, Zhejiang 310024, China
- Westlake
Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang 310024, China
- Institute
of Basic Medical Sciences, Westlake Institute
for Advanced Study, Hangzhou, Zhejiang 310024, China
| | - Fedor V. Subach
- Complex
of NBICS Technologies, National Research
Center “Kurchatov Institute”, Moscow 123182, Russia
| | - Brian O. Smith
- Institute
of Molecular, Cell & Systems Biology, College of Medical Veterinary
& Life Sciences, University of Glasgow, Glasgow G128QQ, United Kingdom
| | - Kiryl D. Piatkevich
- School
of Life Sciences, Westlake University, Hangzhou, Zhejiang 310024, China
- Westlake
Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang 310024, China
- Institute
of Basic Medical Sciences, Westlake Institute
for Advanced Study, Hangzhou, Zhejiang 310024, China
| | - Edward S. Boyden
- McGovern
Institute for Brain Research, MIT, Cambridge, Massachusetts 02139, United States
- Department
of Biological Engineering, MIT, Cambridge, Massachusetts 02139, United States
- Department
of Media Arts & Sciences, MIT, Cambridge, Massachusetts 02139, United States
- Koch
Institute for Integrative Cancer Research, MIT, Cambridge, Massachusetts 02139, United States
- Howard Hughes Medical Institute, Chevy Chase, Maryland 20815, United States
- Department
of Brain and Cognitive Sciences, MIT, Cambridge, Massachusetts 02139, United States
- K.
Lisa Yang Center for Bionics, MIT, Cambridge, Massachusetts 02139, United States
- Center
for Neurobiological Engineering, MIT, Cambridge, Massachusetts 02139, United States
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16
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Wu SY, Shen Y, Shkolnikov I, Campbell RE. Fluorescent Indicators For Biological Imaging of Monatomic Ions. Front Cell Dev Biol 2022; 10:885440. [PMID: 35573682 PMCID: PMC9093666 DOI: 10.3389/fcell.2022.885440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 04/04/2022] [Indexed: 11/13/2022] Open
Abstract
Monatomic ions play critical biological roles including maintaining the cellular osmotic pressure, transmitting signals, and catalyzing redox reactions as cofactors in enzymes. The ability to visualize monatomic ion concentration, and dynamic changes in the concentration, is essential to understanding their many biological functions. A growing number of genetically encodable and synthetic indicators enable the visualization and detection of monatomic ions in biological systems. With this review, we aim to provide a survey of the current landscape of reported indicators. We hope this review will be a useful guide to researchers who are interested in using indicators for biological applications and to tool developers seeking opportunities to create new and improved indicators.
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Affiliation(s)
- Sheng-Yi Wu
- Department of Chemistry, University of Alberta, Edmonton, AB, Canada
| | - Yi Shen
- Department of Chemistry, University of Alberta, Edmonton, AB, Canada
| | - Irene Shkolnikov
- Department of Chemistry, University of Alberta, Edmonton, AB, Canada
- Department of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Robert E. Campbell
- Department of Chemistry, University of Alberta, Edmonton, AB, Canada
- Department of Chemistry, The University of Tokyo, Tokyo, Japan
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17
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Zarowny L, Clavel D, Johannson R, Duarte K, Depernet H, Dupuy J, Baker H, Brown A, Royant A, Campbell RE. Cyan fluorescent proteins derived from mNeonGreen. Protein Eng Des Sel 2022; 35:gzac004. [PMID: 35417013 PMCID: PMC9083105 DOI: 10.1093/protein/gzac004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 03/17/2022] [Accepted: 04/05/2022] [Indexed: 11/13/2022] Open
Abstract
mNeonGreen, an engineered green fluorescent protein (GFP) derived from lancelet, is one of the most brightly fluorescent homologs of Aequorea victoria jellyfish GFP (avGFP) yet reported. In this work, we investigated whether this bright fluorescence might be retained in homologs of mNeonGreen with modified chromophore structures and altered fluorescent hues. We found mNeonGreen to be generally less tolerant than avGFP to chromophore modification by substitution of the key chromophore-forming tyrosine residue with other aromatic amino acids. However, we were ultimately successful in creating a variant, designated as NeonCyan1, with a tryptophan-derived cyan fluorescent protein (CFP)-type chromophore, and two additional mutants with distinct spectral hues. Structural, computational, and photophysical characterization of NeonCyan1 and its variants provided insight into the factors that control the fluorescence emission color. Though not recommended as replacements for contemporary CFP variants, we demonstrate that NeonCyan1 variants are potentially suitable for live cell imaging applications.
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Affiliation(s)
- Landon Zarowny
- Department of Chemistry, University of Alberta, Edmonton T6G 2G2, Canada
| | - Damien Clavel
- Univ. Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale (IBS), 38000 Grenoble, France
| | - Ryan Johannson
- Department of Chemistry, University of Alberta, Edmonton T6G 2G2, Canada
| | - Kévin Duarte
- Univ. Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale (IBS), 38000 Grenoble, France
| | - Hadrien Depernet
- Structural Biology Group, European Synchrotron Radiation Facility, 38043 Grenoble, France
| | - Jérôme Dupuy
- Univ. Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale (IBS), 38000 Grenoble, France
| | - Heather Baker
- Department of Chemistry, University of Alberta, Edmonton T6G 2G2, Canada
| | - Alex Brown
- Department of Chemistry, University of Alberta, Edmonton T6G 2G2, Canada
| | - Antoine Royant
- Univ. Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale (IBS), 38000 Grenoble, France
- Structural Biology Group, European Synchrotron Radiation Facility, 38043 Grenoble, France
| | - Robert E Campbell
- Department of Chemistry, University of Alberta, Edmonton T6G 2G2, Canada
- Department of Chemistry, University of Tokyo, Tokyo 113-0033, Japan
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18
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Sotskov VP, Pospelov NA, Plusnin VV, Anokhin KV. Calcium Imaging Reveals Fast Tuning Dynamics of Hippocampal Place Cells and CA1 Population Activity during Free Exploration Task in Mice. Int J Mol Sci 2022; 23:ijms23020638. [PMID: 35054826 PMCID: PMC8775446 DOI: 10.3390/ijms23020638] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 01/01/2022] [Accepted: 01/04/2022] [Indexed: 02/06/2023] Open
Abstract
Hippocampal place cells are a well-known object in neuroscience, but their place field formation in the first moments of navigating in a novel environment remains an ill-defined process. To address these dynamics, we performed in vivo imaging of neuronal activity in the CA1 field of the mouse hippocampus using genetically encoded green calcium indicators, including the novel NCaMP7 and FGCaMP7, designed specifically for in vivo calcium imaging. Mice were injected with a viral vector encoding calcium sensor, head-mounted with an NVista HD miniscope, and allowed to explore a completely novel environment (circular track surrounded by visual cues) without any reinforcement stimuli, in order to avoid potential interference from reward-related behavior. First, we calculated the average time required for each CA1 cell to acquire its place field. We found that 25% of CA1 place fields were formed at the first arrival in the corresponding place, while the average tuning latency for all place fields in a novel environment equaled 247 s. After 24 h, when the environment was familiar to the animals, place fields formed faster, independent of retention of cognitive maps during this session. No cumulation of selectivity score was observed between these two sessions. Using dimensionality reduction, we demonstrated that the population activity of rapidly tuned CA1 place cells allowed the reconstruction of the geometry of the navigated circular maze; the distribution of reconstruction error between the mice was consistent with the distribution of the average place field selectivity score in them. Our data thus show that neuronal activity recorded with genetically encoded calcium sensors revealed fast behavior-dependent plasticity in the mouse hippocampus, resulting in the rapid formation of place fields and population activity that allowed the reconstruction of the geometry of the navigated maze.
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Affiliation(s)
- Vladimir P. Sotskov
- Institute for Advanced Brain Studies, Lomonosov Moscow State University, 119991 Moscow, Russia;
- Correspondence: (V.P.S.); (K.V.A.)
| | - Nikita A. Pospelov
- Institute for Advanced Brain Studies, Lomonosov Moscow State University, 119991 Moscow, Russia;
| | - Viktor V. Plusnin
- National Research Center “Kurchatov Institute”, 123098 Moscow, Russia;
- Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia
| | - Konstantin V. Anokhin
- Institute for Advanced Brain Studies, Lomonosov Moscow State University, 119991 Moscow, Russia;
- P.K. Anokhin Institute of Normal Physiology RAS, 125315 Moscow, Russia
- Correspondence: (V.P.S.); (K.V.A.)
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19
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Abdelfattah AS, Ahuja S, Akkin T, Allu SR, Brake J, Boas DA, Buckley EM, Campbell RE, Chen AI, Cheng X, Čižmár T, Costantini I, De Vittorio M, Devor A, Doran PR, El Khatib M, Emiliani V, Fomin-Thunemann N, Fainman Y, Fernandez-Alfonso T, Ferri CGL, Gilad A, Han X, Harris A, Hillman EMC, Hochgeschwender U, Holt MG, Ji N, Kılıç K, Lake EMR, Li L, Li T, Mächler P, Miller EW, Mesquita RC, Nadella KMNS, Nägerl UV, Nasu Y, Nimmerjahn A, Ondráčková P, Pavone FS, Perez Campos C, Peterka DS, Pisano F, Pisanello F, Puppo F, Sabatini BL, Sadegh S, Sakadzic S, Shoham S, Shroff SN, Silver RA, Sims RR, Smith SL, Srinivasan VJ, Thunemann M, Tian L, Tian L, Troxler T, Valera A, Vaziri A, Vinogradov SA, Vitale F, Wang LV, Uhlířová H, Xu C, Yang C, Yang MH, Yellen G, Yizhar O, Zhao Y. Neurophotonic tools for microscopic measurements and manipulation: status report. NEUROPHOTONICS 2022; 9:013001. [PMID: 35493335 PMCID: PMC9047450 DOI: 10.1117/1.nph.9.s1.013001] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Neurophotonics was launched in 2014 coinciding with the launch of the BRAIN Initiative focused on development of technologies for advancement of neuroscience. For the last seven years, Neurophotonics' agenda has been well aligned with this focus on neurotechnologies featuring new optical methods and tools applicable to brain studies. While the BRAIN Initiative 2.0 is pivoting towards applications of these novel tools in the quest to understand the brain, this status report reviews an extensive and diverse toolkit of novel methods to explore brain function that have emerged from the BRAIN Initiative and related large-scale efforts for measurement and manipulation of brain structure and function. Here, we focus on neurophotonic tools mostly applicable to animal studies. A companion report, scheduled to appear later this year, will cover diffuse optical imaging methods applicable to noninvasive human studies. For each domain, we outline the current state-of-the-art of the respective technologies, identify the areas where innovation is needed, and provide an outlook for the future directions.
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Affiliation(s)
- Ahmed S. Abdelfattah
- Brown University, Department of Neuroscience, Providence, Rhode Island, United States
| | - Sapna Ahuja
- University of Pennsylvania, Perelman School of Medicine, Department of Biochemistry and Biophysics, Philadelphia, Pennsylvania, United States
- University of Pennsylvania, School of Arts and Sciences, Department of Chemistry, Philadelphia, Pennsylvania, United States
| | - Taner Akkin
- University of Minnesota, Department of Biomedical Engineering, Minneapolis, Minnesota, United States
| | - Srinivasa Rao Allu
- University of Pennsylvania, Perelman School of Medicine, Department of Biochemistry and Biophysics, Philadelphia, Pennsylvania, United States
- University of Pennsylvania, School of Arts and Sciences, Department of Chemistry, Philadelphia, Pennsylvania, United States
| | - Joshua Brake
- Harvey Mudd College, Department of Engineering, Claremont, California, United States
| | - David A. Boas
- Boston University, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Erin M. Buckley
- Georgia Institute of Technology and Emory University, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
- Emory University, Department of Pediatrics, Atlanta, Georgia, United States
| | - Robert E. Campbell
- University of Tokyo, Department of Chemistry, Tokyo, Japan
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
| | - Anderson I. Chen
- Boston University, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Xiaojun Cheng
- Boston University, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Tomáš Čižmár
- Institute of Scientific Instruments of the Czech Academy of Sciences, Brno, Czech Republic
| | - Irene Costantini
- University of Florence, European Laboratory for Non-Linear Spectroscopy, Department of Biology, Florence, Italy
- National Institute of Optics, National Research Council, Rome, Italy
| | - Massimo De Vittorio
- Istituto Italiano di Tecnologia, Center for Biomolecular Nanotechnologies, Arnesano, Italy
| | - Anna Devor
- Boston University, Department of Biomedical Engineering, Boston, Massachusetts, United States
- Massachusetts General Hospital, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, Massachusetts, United States
| | - Patrick R. Doran
- Boston University, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Mirna El Khatib
- University of Pennsylvania, Perelman School of Medicine, Department of Biochemistry and Biophysics, Philadelphia, Pennsylvania, United States
- University of Pennsylvania, School of Arts and Sciences, Department of Chemistry, Philadelphia, Pennsylvania, United States
| | | | - Natalie Fomin-Thunemann
- Boston University, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Yeshaiahu Fainman
- University of California San Diego, Department of Electrical and Computer Engineering, La Jolla, California, United States
| | - Tomas Fernandez-Alfonso
- University College London, Department of Neuroscience, Physiology and Pharmacology, London, United Kingdom
| | - Christopher G. L. Ferri
- University of California San Diego, Departments of Neurosciences, La Jolla, California, United States
| | - Ariel Gilad
- The Hebrew University of Jerusalem, Institute for Medical Research Israel–Canada, Department of Medical Neurobiology, Faculty of Medicine, Jerusalem, Israel
| | - Xue Han
- Boston University, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Andrew Harris
- Weizmann Institute of Science, Department of Brain Sciences, Rehovot, Israel
| | | | - Ute Hochgeschwender
- Central Michigan University, Department of Neuroscience, Mount Pleasant, Michigan, United States
| | - Matthew G. Holt
- University of Porto, Instituto de Investigação e Inovação em Saúde (i3S), Porto, Portugal
| | - Na Ji
- University of California Berkeley, Department of Physics, Berkeley, California, United States
| | - Kıvılcım Kılıç
- Boston University, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Evelyn M. R. Lake
- Yale School of Medicine, Department of Radiology and Biomedical Imaging, New Haven, Connecticut, United States
| | - Lei Li
- California Institute of Technology, Andrew and Peggy Cherng Department of Medical Engineering, Department of Electrical Engineering, Pasadena, California, United States
| | - Tianqi Li
- University of Minnesota, Department of Biomedical Engineering, Minneapolis, Minnesota, United States
| | - Philipp Mächler
- Boston University, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Evan W. Miller
- University of California Berkeley, Departments of Chemistry and Molecular & Cell Biology and Helen Wills Neuroscience Institute, Berkeley, California, United States
| | | | | | - U. Valentin Nägerl
- Interdisciplinary Institute for Neuroscience University of Bordeaux & CNRS, Bordeaux, France
| | - Yusuke Nasu
- University of Tokyo, Department of Chemistry, Tokyo, Japan
| | - Axel Nimmerjahn
- Salk Institute for Biological Studies, Waitt Advanced Biophotonics Center, La Jolla, California, United States
| | - Petra Ondráčková
- Institute of Scientific Instruments of the Czech Academy of Sciences, Brno, Czech Republic
| | - Francesco S. Pavone
- National Institute of Optics, National Research Council, Rome, Italy
- University of Florence, European Laboratory for Non-Linear Spectroscopy, Department of Physics, Florence, Italy
| | - Citlali Perez Campos
- Columbia University, Zuckerman Mind Brain Behavior Institute, New York, United States
| | - Darcy S. Peterka
- Columbia University, Zuckerman Mind Brain Behavior Institute, New York, United States
| | - Filippo Pisano
- Istituto Italiano di Tecnologia, Center for Biomolecular Nanotechnologies, Arnesano, Italy
| | - Ferruccio Pisanello
- Istituto Italiano di Tecnologia, Center for Biomolecular Nanotechnologies, Arnesano, Italy
| | - Francesca Puppo
- University of California San Diego, Departments of Neurosciences, La Jolla, California, United States
| | - Bernardo L. Sabatini
- Harvard Medical School, Howard Hughes Medical Institute, Department of Neurobiology, Boston, Massachusetts, United States
| | - Sanaz Sadegh
- University of California San Diego, Departments of Neurosciences, La Jolla, California, United States
| | - Sava Sakadzic
- Massachusetts General Hospital, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, Massachusetts, United States
| | - Shy Shoham
- New York University Grossman School of Medicine, Tech4Health and Neuroscience Institutes, New York, New York, United States
| | - Sanaya N. Shroff
- Boston University, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - R. Angus Silver
- University College London, Department of Neuroscience, Physiology and Pharmacology, London, United Kingdom
| | - Ruth R. Sims
- Sorbonne University, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Spencer L. Smith
- University of California Santa Barbara, Department of Electrical and Computer Engineering, Santa Barbara, California, United States
| | - Vivek J. Srinivasan
- New York University Langone Health, Departments of Ophthalmology and Radiology, New York, New York, United States
| | - Martin Thunemann
- Boston University, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Lei Tian
- Boston University, Departments of Electrical Engineering and Biomedical Engineering, Boston, Massachusetts, United States
| | - Lin Tian
- University of California Davis, Department of Biochemistry and Molecular Medicine, Davis, California, United States
| | - Thomas Troxler
- University of Pennsylvania, Perelman School of Medicine, Department of Biochemistry and Biophysics, Philadelphia, Pennsylvania, United States
- University of Pennsylvania, School of Arts and Sciences, Department of Chemistry, Philadelphia, Pennsylvania, United States
| | - Antoine Valera
- University College London, Department of Neuroscience, Physiology and Pharmacology, London, United Kingdom
| | - Alipasha Vaziri
- Rockefeller University, Laboratory of Neurotechnology and Biophysics, New York, New York, United States
- The Rockefeller University, The Kavli Neural Systems Institute, New York, New York, United States
| | - Sergei A. Vinogradov
- University of Pennsylvania, Perelman School of Medicine, Department of Biochemistry and Biophysics, Philadelphia, Pennsylvania, United States
- University of Pennsylvania, School of Arts and Sciences, Department of Chemistry, Philadelphia, Pennsylvania, United States
| | - Flavia Vitale
- Center for Neuroengineering and Therapeutics, Departments of Neurology, Bioengineering, Physical Medicine and Rehabilitation, Philadelphia, Pennsylvania, United States
| | - Lihong V. Wang
- California Institute of Technology, Andrew and Peggy Cherng Department of Medical Engineering, Department of Electrical Engineering, Pasadena, California, United States
| | - Hana Uhlířová
- Institute of Scientific Instruments of the Czech Academy of Sciences, Brno, Czech Republic
| | - Chris Xu
- Cornell University, School of Applied and Engineering Physics, Ithaca, New York, United States
| | - Changhuei Yang
- California Institute of Technology, Departments of Electrical Engineering, Bioengineering and Medical Engineering, Pasadena, California, United States
| | - Mu-Han Yang
- University of California San Diego, Department of Electrical and Computer Engineering, La Jolla, California, United States
| | - Gary Yellen
- Harvard Medical School, Department of Neurobiology, Boston, Massachusetts, United States
| | - Ofer Yizhar
- Weizmann Institute of Science, Department of Brain Sciences, Rehovot, Israel
| | - Yongxin Zhao
- Carnegie Mellon University, Department of Biological Sciences, Pittsburgh, Pennsylvania, United States
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20
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Subach OM, Vlaskina AV, Agapova YK, Dorovatovskii PV, Nikolaeva AY, Ivashkina OI, Popov VO, Piatkevich KD, Khrenova MG, Smirnova TA, Boyko KM, Subach FV. LSSmScarlet, dCyRFP2s, dCyOFP2s and CRISPRed2s, Genetically Encoded Red Fluorescent Proteins with a Large Stokes Shift. Int J Mol Sci 2021; 22:12887. [PMID: 34884694 PMCID: PMC8657457 DOI: 10.3390/ijms222312887] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 11/20/2021] [Accepted: 11/24/2021] [Indexed: 11/24/2022] Open
Abstract
Genetically encoded red fluorescent proteins with a large Stokes shift (LSSRFPs) can be efficiently co-excited with common green FPs both under single- and two-photon microscopy, thus enabling dual-color imaging using a single laser. Recent progress in protein development resulted in a great variety of novel LSSRFPs; however, the selection of the right LSSRFP for a given application is hampered by the lack of a side-by-side comparison of the LSSRFPs' performance. In this study, we employed rational design and random mutagenesis to convert conventional bright RFP mScarlet into LSSRFP, called LSSmScarlet, characterized by excitation/emission maxima at 470/598 nm. In addition, we utilized the previously reported LSSRFPs mCyRFP1, CyOFP1, and mCRISPRed as templates for directed molecular evolution to develop their optimized versions, called dCyRFP2s, dCyOFP2s and CRISPRed2s. We performed a quantitative assessment of the developed LSSRFPs and their precursors in vitro on purified proteins and compared their brightness at 488 nm excitation in the mammalian cells. The monomeric LSSmScarlet protein was successfully utilized for the confocal imaging of the structural proteins in live mammalian cells and multicolor confocal imaging in conjugation with other FPs. LSSmScarlet was successfully applied for dual-color two-photon imaging in live mammalian cells. We also solved the X-ray structure of the LSSmScarlet protein at the resolution of 1.4 Å that revealed a hydrogen bond network supporting excited-state proton transfer (ESPT). Quantum mechanics/molecular mechanics molecular dynamic simulations confirmed the ESPT mechanism of a large Stokes shift. Structure-guided mutagenesis revealed the role of R198 residue in ESPT that allowed us to generate a variant with improved pH stability. Finally, we showed that LSSmScarlet protein is not appropriate for STED microscopy as a consequence of LSSRed-to-Red photoconversion with high-power 775 nm depletion light.
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Affiliation(s)
- Oksana M. Subach
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, 123182 Moscow, Russia; (O.M.S.); (A.V.V.); (Y.K.A.); (P.V.D.); (A.Y.N.); (O.I.I.); (V.O.P.)
| | - Anna V. Vlaskina
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, 123182 Moscow, Russia; (O.M.S.); (A.V.V.); (Y.K.A.); (P.V.D.); (A.Y.N.); (O.I.I.); (V.O.P.)
| | - Yuliya K. Agapova
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, 123182 Moscow, Russia; (O.M.S.); (A.V.V.); (Y.K.A.); (P.V.D.); (A.Y.N.); (O.I.I.); (V.O.P.)
| | - Pavel V. Dorovatovskii
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, 123182 Moscow, Russia; (O.M.S.); (A.V.V.); (Y.K.A.); (P.V.D.); (A.Y.N.); (O.I.I.); (V.O.P.)
| | - Alena Y. Nikolaeva
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, 123182 Moscow, Russia; (O.M.S.); (A.V.V.); (Y.K.A.); (P.V.D.); (A.Y.N.); (O.I.I.); (V.O.P.)
- Bach Institute of Biochemistry, Research Centre of Biotechnology of the Russian Academy of Sciences, 119071 Moscow, Russia; (M.G.K.); (K.M.B.)
| | - Olga I. Ivashkina
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, 123182 Moscow, Russia; (O.M.S.); (A.V.V.); (Y.K.A.); (P.V.D.); (A.Y.N.); (O.I.I.); (V.O.P.)
- Laboratory for Neurobiology of Memory, P.K. Anokhin Research Institute of Normal Physiology, 125315 Moscow, Russia
- Institute for Advanced Brain Studies, M.V. Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Vladimir O. Popov
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, 123182 Moscow, Russia; (O.M.S.); (A.V.V.); (Y.K.A.); (P.V.D.); (A.Y.N.); (O.I.I.); (V.O.P.)
- Bach Institute of Biochemistry, Research Centre of Biotechnology of the Russian Academy of Sciences, 119071 Moscow, Russia; (M.G.K.); (K.M.B.)
- Faculty of Biology, M.V. Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Kiryl D. Piatkevich
- School of Life Sciences, Westlake University, Hangzhou 310024, China;
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou 310024, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou 310024, China
| | - Maria G. Khrenova
- Bach Institute of Biochemistry, Research Centre of Biotechnology of the Russian Academy of Sciences, 119071 Moscow, Russia; (M.G.K.); (K.M.B.)
- Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Tatiana A. Smirnova
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia;
| | - Konstantin M. Boyko
- Bach Institute of Biochemistry, Research Centre of Biotechnology of the Russian Academy of Sciences, 119071 Moscow, Russia; (M.G.K.); (K.M.B.)
| | - Fedor V. Subach
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, 123182 Moscow, Russia; (O.M.S.); (A.V.V.); (Y.K.A.); (P.V.D.); (A.Y.N.); (O.I.I.); (V.O.P.)
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21
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Zhou Y, Ding M, Nagel G, Konrad KR, Gao S. Advances and prospects of rhodopsin-based optogenetics in plant research. PLANT PHYSIOLOGY 2021; 187:572-589. [PMID: 35237820 PMCID: PMC8491038 DOI: 10.1093/plphys/kiab338] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 07/05/2021] [Indexed: 05/20/2023]
Abstract
Microbial rhodopsins have advanced optogenetics since the discovery of channelrhodopsins almost two decades ago. During this time an abundance of microbial rhodopsins has been discovered, engineered, and improved for studies in neuroscience and other animal research fields. Optogenetic applications in plant research, however, lagged largely behind. Starting with light-regulated gene expression, optogenetics has slowly expanded into plant research. The recently established all-trans retinal production in plants now enables the use of many microbial opsins, bringing extra opportunities to plant research. In this review, we summarize the recent advances of rhodopsin-based plant optogenetics and provide a perspective for future use, combined with fluorescent sensors to monitor physiological parameters.
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Affiliation(s)
- Yang Zhou
- Institute of Physiology, Department of Neurophysiology, Biocenter, University of Wuerzburg, Wuerzburg 97070, Germany
| | - Meiqi Ding
- Institute for Molecular Plant Physiology and Biophysics, Julius-von-Sachs-Institute, Biocenter, University of Wuerzburg, Wuerzburg 97082, Germany
| | - Georg Nagel
- Institute of Physiology, Department of Neurophysiology, Biocenter, University of Wuerzburg, Wuerzburg 97070, Germany
| | - Kai R. Konrad
- Institute for Molecular Plant Physiology and Biophysics, Julius-von-Sachs-Institute, Biocenter, University of Wuerzburg, Wuerzburg 97082, Germany
| | - Shiqiang Gao
- Institute of Physiology, Department of Neurophysiology, Biocenter, University of Wuerzburg, Wuerzburg 97070, Germany
- Author for communication:
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22
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Li ES, Saha MS. Optimizing Calcium Detection Methods in Animal Systems: A Sandbox for Synthetic Biology. Biomolecules 2021; 11:343. [PMID: 33668387 PMCID: PMC7996158 DOI: 10.3390/biom11030343] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 02/19/2021] [Accepted: 02/21/2021] [Indexed: 12/16/2022] Open
Abstract
Since the 1970s, the emergence and expansion of novel methods for calcium ion (Ca2+) detection have found diverse applications in vitro and in vivo across a series of model animal systems. Matched with advances in fluorescence imaging techniques, the improvements in the functional range and stability of various calcium indicators have significantly enhanced more accurate study of intracellular Ca2+ dynamics and its effects on cell signaling, growth, differentiation, and regulation. Nonetheless, the current limitations broadly presented by organic calcium dyes, genetically encoded calcium indicators, and calcium-responsive nanoparticles suggest a potential path toward more rapid optimization by taking advantage of a synthetic biology approach. This engineering-oriented discipline applies principles of modularity and standardization to redesign and interrogate endogenous biological systems. This review will elucidate how novel synthetic biology technologies constructed for eukaryotic systems can offer a promising toolkit for interfacing with calcium signaling and overcoming barriers in order to accelerate the process of Ca2+ detection optimization.
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Affiliation(s)
| | - Margaret S. Saha
- Department of Biology, College of William and Mary, Williamsburg, VA 23185, USA;
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23
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Kim HS, Kim JE, Hwangbo A, Akerboom J, Looger LL, Duncan R, Son H, Czymmek KJ, Kang S. Evaluation of multi-color genetically encoded Ca 2+ indicators in filamentous fungi. Fungal Genet Biol 2021; 149:103540. [PMID: 33607281 DOI: 10.1016/j.fgb.2021.103540] [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: 08/21/2020] [Revised: 01/27/2021] [Accepted: 01/30/2021] [Indexed: 11/18/2022]
Abstract
Genetically encoded Ca2+ indicators (GECIs) enable long-term monitoring of cellular and subcellular dynamics of this second messenger in response to environmental and developmental cues without relying on exogenous dyes. Continued development and optimization in GECIs, combined with advances in gene manipulation, offer new opportunities for investigating the mechanism of Ca2+ signaling in fungi, ranging from documenting Ca2+ signatures under diverse conditions and genetic backgrounds to evaluating how changes in Ca2+ signature impact calcium-binding proteins and subsequent cellular changes. Here, we attempted to express multi-color (green, yellow, blue, cyan, and red) circularly permuted fluorescent protein (FP)-based Ca2+ indicators driven by multiple fungal promoters in Fusarium oxysporum, F. graminearum, and Neurospora crassa. Several variants were successfully expressed, with GCaMP5G driven by the Magnaporthe oryzae ribosomal protein 27 and F. verticillioides elongation factor-1α gene promoters being optimal for F. graminearum and F. oxysporum, respectively. Transformants expressing GCaMP5G were compared with those expressing YC3.60, a ratiometric Cameleon Ca2+ indicator. Wild-type and three Ca2+ signaling mutants of F. graminearum expressing GCaMP5G exhibited improved signal-to-noise and increased temporal and spatial resolution and are also more amenable to studies involving multiple FPs compared to strains expressing YC3.60.
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Affiliation(s)
- Hye-Seon Kim
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, United States; Delaware Biotechnology Institute, Newark, DE 19711, United States
| | - Jung-Eun Kim
- Department of Plant Pathology & Environmental Microbiology, The Pennsylvania State University, University Park, PA 16802, United States
| | - Aram Hwangbo
- Department of Agricultural Biotechnology, Seoul National University, Seoul 151-921, Republic of Korea
| | - Jasper Akerboom
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, United States
| | - Loren L Looger
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, United States
| | - Randall Duncan
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, United States
| | - Hokyoung Son
- Department of Agricultural Biotechnology, Seoul National University, Seoul 151-921, Republic of Korea
| | - Kirk J Czymmek
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, United States; Delaware Biotechnology Institute, Newark, DE 19711, United States; Donald Danforth Plant Science Center, Saint Louis, MO 63132, United States.
| | - Seogchan Kang
- Department of Plant Pathology & Environmental Microbiology, The Pennsylvania State University, University Park, PA 16802, United States.
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24
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Baek K, Ji K, Peng W, Liyanaarachchi SM, Dodani SC. The design and evolution of fluorescent protein-based sensors for monoatomic ions in biology. Protein Eng Des Sel 2021; 34:gzab023. [PMID: 34581820 PMCID: PMC8477612 DOI: 10.1093/protein/gzab023] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Revised: 08/18/2021] [Accepted: 08/18/2021] [Indexed: 12/15/2022] Open
Abstract
Living cells rely on a finely tuned symphony of inorganic ion gradients composed of both cations and anions. This delicate balance is maintained by biological receptors all acting in concert to selectively recognize and position ions for homeostasis. These dynamic processes can be intercepted and visualized with optical microscopy at the organismal, tissue, cellular and subcellular levels using fluorescent protein-based biosensors. Since the first report of such tool for calcium (Ca2+) in 1997, outstanding biological questions and innovations in protein engineering along with associated fields have driven the development of new biosensors for Ca2+ and beyond. In this Review, we summarize a workflow that can be used to generate fluorescent protein-based biosensors to study monoatomic ions in biology. To showcase the scope of this approach, we highlight recent advances reported for Ca2+ biosensors and in detail discuss representative case studies of biosensors reported in the last four years for potassium (K+), magnesium (Mg2+), copper (Cu2+/+), lanthanide (Ln3+) and chloride (Cl-) ions.
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Affiliation(s)
- Kiheon Baek
- Department of Chemistry and Biochemistry, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX 75080, USA
| | - Ke Ji
- Department of Chemistry and Biochemistry, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX 75080, USA
| | - Weicheng Peng
- Department of Chemistry and Biochemistry, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX 75080, USA
| | - Sureshee M Liyanaarachchi
- Department of Chemistry and Biochemistry, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX 75080, USA
| | - Sheel C Dodani
- Department of Chemistry and Biochemistry, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX 75080, USA
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25
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Structure- and mechanism-guided design of single fluorescent protein-based biosensors. Nat Chem Biol 2021; 17:509-518. [PMID: 33558715 DOI: 10.1038/s41589-020-00718-x] [Citation(s) in RCA: 103] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 12/02/2020] [Indexed: 12/22/2022]
Abstract
Intensiometric genetically encoded biosensors, based on allosteric modulation of the fluorescence of a single fluorescent protein, are powerful tools for enabling imaging of neural activities and other cellular biochemical events. The archetypical example of such biosensors is the GCaMP series of Ca2+ biosensors, which have been steadily improved over the past two decades and are now indispensable tools for neuroscience. However, no other biosensors have reached levels of performance, or had revolutionary impacts within specific disciplines, comparable to that of the Ca2+ biosensors. Of the many reasons why this has been the case, a critical one has been a general black-box view of biosensor structure and mechanism. With this Perspective, we aim to summarize what is known about biosensor structure and mechanisms and, based on this foundation, provide guidelines to accelerate the development of a broader range of biosensors with performance comparable to that of the GCaMP series.
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26
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Roberts R, Authier S, Mellon RD, Morton M, Suzuki I, Tjalkens RB, Valentin JP, Pierson JB. Can We Panelize Seizure? Toxicol Sci 2021; 179:3-13. [PMID: 33165543 DOI: 10.1093/toxsci/kfaa167] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Seizure liability remains a significant cause of attrition in drug discovery and development, leading to loss of competitiveness, delays, and increased costs. Current detection methods rely on observations made in in vivo studies intended to support clinical trials, such as tremors or other abnormal movements. These signs could be missed or misinterpreted; thus, definitive confirmation of drug-induced seizure requires a follow-up electroencephalogram study. There has been progress in in vivo detection of seizure using automated video systems that record and analyze animal movements. Nonetheless, it would be preferable to have earlier prediction of seizurogenic risk that could be used to eliminate liabilities early in discovery while there are options for medicinal chemists making potential new drugs. Attrition due to cardiac adverse events has benefited from routine early screening; could we reduce attrition due to seizure using a similar approach? Specifically, microelectrode arrays could be used to detect potential seizurogenic signals in stem-cell-derived neurons. In addition, there is clear evidence implicating neuronal voltage-gated and ligand-gated ion channels, GPCRs and transporters in seizure. Interactions with surrounding glial cells during states of stress or inflammation can also modulate ion channel function in neurons, adding to the challenge of seizure prediction. It is timely to evaluate the opportunity to develop an in vitro assessment of seizure linked to a panel of ion channel assays that predict seizure, with the aim of influencing structure-activity relationship at the design stage and eliminating compounds predicted to be associated with pro-seizurogenic state.
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Affiliation(s)
- Ruth Roberts
- ApconiX, Alderley Park, SK10 4TG, UK.,University of Birmingham, B15 2SD, UK
| | | | - R Daniel Mellon
- US Food and Drug Administration, Silver Spring, Maryland 20993
| | | | - Ikuro Suzuki
- Tohoku Institute of Technology, Sendai, 980-8577, Japan
| | - Ronald B Tjalkens
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, Colorado 80523
| | - Jean-Pierre Valentin
- UCB Biopharma SRL, Early Solutions, Development Science, Investigative Toxicology, Chemin du Foriest, B-1420, Braine-l'Alleud, Belgium
| | - Jennifer B Pierson
- Health and Environmental Sciences Institute, Washington, District of Columbia 20005
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Potekhina ES, Bass DY, Kelmanson IV, Fetisova ES, Ivanenko AV, Belousov VV, Bilan DS. Drug Screening with Genetically Encoded Fluorescent Sensors: Today and Tomorrow. Int J Mol Sci 2020; 22:E148. [PMID: 33375682 PMCID: PMC7794770 DOI: 10.3390/ijms22010148] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 12/18/2020] [Accepted: 12/24/2020] [Indexed: 02/07/2023] Open
Abstract
Genetically-encoded fluorescent sensors have been actively developed over the last few decades and used in live imaging and drug screening. Real-time monitoring of drug action in a specific cellular compartment, organ, or tissue type; the ability to screen at the single-cell resolution; and the elimination of false-positive results caused by low drug bioavailability that is not detected by in vitro testing methods are a few of the obvious benefits of using genetically-encoded fluorescent sensors in drug screening. In combination with high-throughput screening (HTS), some genetically-encoded fluorescent sensors may provide high reproducibility and robustness to assays. We provide a brief overview of successful, perspective, and hopeful attempts at using genetically encoded fluorescent sensors in HTS of modulators of ion channels, Ca2+ homeostasis, GPCR activity, and for screening cytotoxic, anticancer, and anti-parasitic compounds. We discuss the advantages of sensors in whole organism drug screening models and the perspectives of the combination of human disease modeling by CRISPR techniques with genetically encoded fluorescent sensors for drug screening.
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Affiliation(s)
- Ekaterina S. Potekhina
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia; (D.Y.B.); (I.V.K.); (E.S.F.); (A.V.I.); (V.V.B.)
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
| | - Dina Y. Bass
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia; (D.Y.B.); (I.V.K.); (E.S.F.); (A.V.I.); (V.V.B.)
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
| | - Ilya V. Kelmanson
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia; (D.Y.B.); (I.V.K.); (E.S.F.); (A.V.I.); (V.V.B.)
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
| | - Elena S. Fetisova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia; (D.Y.B.); (I.V.K.); (E.S.F.); (A.V.I.); (V.V.B.)
| | - Alexander V. Ivanenko
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia; (D.Y.B.); (I.V.K.); (E.S.F.); (A.V.I.); (V.V.B.)
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
| | - Vsevolod V. Belousov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia; (D.Y.B.); (I.V.K.); (E.S.F.); (A.V.I.); (V.V.B.)
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
- Federal Center of Brain Research and Neurotechnologies of the Federal Medical Biological Agency, 117997 Moscow, Russia
| | - Dmitry S. Bilan
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia; (D.Y.B.); (I.V.K.); (E.S.F.); (A.V.I.); (V.V.B.)
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
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FRCaMP, a Red Fluorescent Genetically Encoded Calcium Indicator Based on Calmodulin from Schizosaccharomyces Pombe Fungus. Int J Mol Sci 2020; 22:ijms22010111. [PMID: 33374320 PMCID: PMC7794825 DOI: 10.3390/ijms22010111] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 12/22/2020] [Accepted: 12/22/2020] [Indexed: 11/16/2022] Open
Abstract
Red fluorescent genetically encoded calcium indicators (GECIs) have expanded the available pallet of colors used for the visualization of neuronal calcium activity in vivo. However, their calcium-binding domain is restricted by calmodulin from metazoans. In this study, we developed red GECI, called FRCaMP, using calmodulin (CaM) from Schizosaccharomyces pombe fungus as a calcium binding domain. Compared to the R-GECO1 indicator in vitro, the purified protein FRCaMP had similar spectral characteristics, brightness, and pH stability but a 1.3-fold lower ΔF/F calcium response and 2.6-fold tighter calcium affinity with Kd of 441 nM and 2.4-6.6-fold lower photostability. In the cytosol of cultured HeLa cells, FRCaMP visualized calcium transients with a ΔF/F dynamic range of 5.6, which was similar to that of R-GECO1. FRCaMP robustly visualized the spontaneous activity of neuronal cultures and had a similar ΔF/F dynamic range of 1.7 but 2.1-fold faster decay kinetics vs. NCaMP7. On electrically stimulated cultured neurons, FRCaMP demonstrated 1.8-fold faster decay kinetics and 1.7-fold lower ΔF/F values per one action potential of 0.23 compared to the NCaMP7 indicator. The fungus-originating CaM of the FRCaMP indicator version with a deleted M13-like peptide did not interact with the cytosolic environment of the HeLa cells in contrast to the metazoa-originating CaM of the similarly truncated version of the GCaMP6s indicator with a deleted M13-like peptide. Finally, we generated a split version of the FRCaMP indicator, which allowed the simultaneous detection of calcium transients and the heterodimerization of bJun/bFos interacting proteins in the nuclei of HeLa cells with a ΔF/F dynamic range of 9.4 and a contrast of 2.3-3.5, respectively.
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29
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Kostyuk AI, Panova AS, Kokova AD, Kotova DA, Maltsev DI, Podgorny OV, Belousov VV, Bilan DS. In Vivo Imaging with Genetically Encoded Redox Biosensors. Int J Mol Sci 2020; 21:E8164. [PMID: 33142884 PMCID: PMC7662651 DOI: 10.3390/ijms21218164] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 10/28/2020] [Accepted: 10/29/2020] [Indexed: 12/13/2022] Open
Abstract
Redox reactions are of high fundamental and practical interest since they are involved in both normal physiology and the pathogenesis of various diseases. However, this area of research has always been a relatively problematic field in the context of analytical approaches, mostly because of the unstable nature of the compounds that are measured. Genetically encoded sensors allow for the registration of highly reactive molecules in real-time mode and, therefore, they began a new era in redox biology. Their strongest points manifest most brightly in in vivo experiments and pave the way for the non-invasive investigation of biochemical pathways that proceed in organisms from different systematic groups. In the first part of the review, we briefly describe the redox sensors that were used in vivo as well as summarize the model systems to which they were applied. Next, we thoroughly discuss the biological results obtained in these studies in regard to animals, plants, as well as unicellular eukaryotes and prokaryotes. We hope that this work reflects the amazing power of this technology and can serve as a useful guide for biologists and chemists who work in the field of redox processes.
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Affiliation(s)
- Alexander I. Kostyuk
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia; (A.I.K.); (A.S.P.); (A.D.K.); (D.A.K.); (D.I.M.); (O.V.P.); (V.V.B.)
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
| | - Anastasiya S. Panova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia; (A.I.K.); (A.S.P.); (A.D.K.); (D.A.K.); (D.I.M.); (O.V.P.); (V.V.B.)
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
| | - Aleksandra D. Kokova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia; (A.I.K.); (A.S.P.); (A.D.K.); (D.A.K.); (D.I.M.); (O.V.P.); (V.V.B.)
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
| | - Daria A. Kotova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia; (A.I.K.); (A.S.P.); (A.D.K.); (D.A.K.); (D.I.M.); (O.V.P.); (V.V.B.)
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
| | - Dmitry I. Maltsev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia; (A.I.K.); (A.S.P.); (A.D.K.); (D.A.K.); (D.I.M.); (O.V.P.); (V.V.B.)
- Federal Center for Cerebrovascular Pathology and Stroke, 117997 Moscow, Russia
| | - Oleg V. Podgorny
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia; (A.I.K.); (A.S.P.); (A.D.K.); (D.A.K.); (D.I.M.); (O.V.P.); (V.V.B.)
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
| | - Vsevolod V. Belousov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia; (A.I.K.); (A.S.P.); (A.D.K.); (D.A.K.); (D.I.M.); (O.V.P.); (V.V.B.)
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
- Federal Center for Cerebrovascular Pathology and Stroke, 117997 Moscow, Russia
- Institute for Cardiovascular Physiology, Georg August University Göttingen, D-37073 Göttingen, Germany
| | - Dmitry S. Bilan
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia; (A.I.K.); (A.S.P.); (A.D.K.); (D.A.K.); (D.I.M.); (O.V.P.); (V.V.B.)
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
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Zarowny L, Aggarwal A, Rutten VMS, Kolb I, Patel R, Huang HY, Chang YF, Phan T, Kanyo R, Ahrens MB, Allison WT, Podgorski K, Campbell RE. Bright and High-Performance Genetically Encoded Ca 2+ Indicator Based on mNeonGreen Fluorescent Protein. ACS Sens 2020; 5:1959-1968. [PMID: 32571014 DOI: 10.1021/acssensors.0c00279] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Genetically encodable calcium ion (Ca2+) indicators (GECIs) based on green fluorescent proteins (GFP) are powerful tools for imaging of cell signaling and neural activity in model organisms. Following almost 2 decades of steady improvements in the Aequorea victoria GFP-based GCaMP series of GECIs, the performance of the most recent generation (i.e., jGCaMP7) may have reached its practical limit due to the inherent properties of GFP. In an effort to sustain the steady progression toward ever-improved GECIs, we undertook the development of a new GECI based on the bright monomeric GFP, mNeonGreen (mNG). The resulting indicator, mNG-GECO1, is 60% brighter than GCaMP6s in vitro and provides comparable performance as demonstrated by imaging Ca2+ dynamics in cultured cells, primary neurons, and in vivo in larval zebrafish. These results suggest that mNG-GECO1 is a promising next-generation GECI that could inherit the mantle of GCaMP and allow the steady improvement of GECIs to continue for generations to come.
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Affiliation(s)
- Landon Zarowny
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Abhi Aggarwal
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia 20147, United States
| | - Virginia M. S. Rutten
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia 20147, United States
- Gatsby Computational Neuroscience Unit, UCL, London WC1E 6BT, U.K
| | - Ilya Kolb
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia 20147, United States
| | - Ronak Patel
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia 20147, United States
| | - Hsin-Yi Huang
- LumiSTAR Biotechnology, Inc., National Biotechnology Research Park, Taipei City 115, Taiwan
| | - Yu-Fen Chang
- LumiSTAR Biotechnology, Inc., National Biotechnology Research Park, Taipei City 115, Taiwan
| | - Tiffany Phan
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Richard Kanyo
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Misha B. Ahrens
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia 20147, United States
| | - W. Ted Allison
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Kaspar Podgorski
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia 20147, United States
| | - 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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31
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Moeyaert B, Dedecker P. Genetically encoded biosensors based on innovative scaffolds. Int J Biochem Cell Biol 2020; 125:105761. [PMID: 32504671 DOI: 10.1016/j.biocel.2020.105761] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 04/27/2020] [Accepted: 04/29/2020] [Indexed: 12/12/2022]
Abstract
Genetically encoded biosensors are indispensable tools for visualizing the spatiotemporal dynamics of analytes or processes in living cells in vitro and in vivo. Their widespread adaptation has gone hand in hand with the development of sensors for new analytes or processes and improved functionality and robustness. In this review, we highlight some of the recent advances in genetically encoded biosensor development, with a special focus on novel and innovative scaffolds that will lead to new possibilities in the future.
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Affiliation(s)
- Benjamien Moeyaert
- Laboratory for Nanobiology, Department of Chemistry, KU Leuven, Celestijnenlaan 200G, 3001 Heverlee, Belgium
| | - Peter Dedecker
- Laboratory for Nanobiology, Department of Chemistry, KU Leuven, Celestijnenlaan 200G, 3001 Heverlee, Belgium.
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Barykina NV, Sotskov VP, Gruzdeva AM, Wu YK, Portugues R, Subach OM, Chefanova ES, Plusnin VV, Ivashkina OI, Anokhin KV, Vlaskina AV, Korzhenevskiy DA, Nikolaeva AY, Boyko KM, Rakitina TV, Varizhuk AM, Pozmogova GE, Subach FV. FGCaMP7, an Improved Version of Fungi-Based Ratiometric Calcium Indicator for In Vivo Visualization of Neuronal Activity. Int J Mol Sci 2020; 21:ijms21083012. [PMID: 32344594 PMCID: PMC7215472 DOI: 10.3390/ijms21083012] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Revised: 04/22/2020] [Accepted: 04/23/2020] [Indexed: 01/06/2023] Open
Abstract
Genetically encoded calcium indicators (GECIs) have become a widespread tool for the visualization of neuronal activity. As compared to popular GCaMP GECIs, the FGCaMP indicator benefits from calmodulin and M13-peptide from the fungi Aspergillus niger and Aspergillus fumigatus, which prevent its interaction with the intracellular environment. However, FGCaMP exhibits a two-phase fluorescence behavior with the variation of calcium ion concentration, has moderate sensitivity in neurons (as compared to the GCaMP6s indicator), and has not been fully characterized in vitro and in vivo. To address these limitations, we developed an enhanced version of FGCaMP, called FGCaMP7. FGCaMP7 preserves the ratiometric phenotype of FGCaMP, with a 3.1-fold larger ratiometric dynamic range in vitro. FGCaMP7 demonstrates 2.7- and 8.7-fold greater photostability compared to mEGFP and mTagBFP2 fluorescent proteins in vitro, respectively. The ratiometric response of FGCaMP7 is 1.6- and 1.4-fold higher, compared to the intensiometric response of GCaMP6s, in non-stimulated and stimulated neuronal cultures, respectively. We reveal the inertness of FGCaMP7 to the intracellular environment of HeLa cells using its truncated version with a deleted M13-like peptide; in contrast to the similarly truncated variant of GCaMP6s. We characterize the crystal structure of the parental FGCaMP indicator. Finally, we test the in vivo performance of FGCaMP7 in mouse brain using a two-photon microscope and an NVista miniscope; and in zebrafish using two-color ratiometric confocal imaging.
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Affiliation(s)
- Natalia V. Barykina
- Laboratory for Neurobiology of Memory, P.K. Anokhin Research Institute of Normal Physiology, 125315 Moscow, Russia; (N.V.B.); (O.I.I.); (K.V.A.)
| | - Vladimir P. Sotskov
- Institute for Advanced Brain Studies, M.V. Lomonosov Moscow State University, 119991 Moscow, Russia; (V.P.S.); (A.M.G.)
| | - Anna M. Gruzdeva
- Institute for Advanced Brain Studies, M.V. Lomonosov Moscow State University, 119991 Moscow, Russia; (V.P.S.); (A.M.G.)
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, 123182 Moscow, Russia; (O.M.S.); (V.V.P.); (A.V.V.); (D.A.K.); (A.Y.N.); (T.V.R.)
- Sensorimotor Control Research Group, Max Planck Institute of Neurobiology, 82152 Martinsried, Germany; (Y.K.W.); (R.P.)
| | - You Kure Wu
- Sensorimotor Control Research Group, Max Planck Institute of Neurobiology, 82152 Martinsried, Germany; (Y.K.W.); (R.P.)
| | - Ruben Portugues
- Sensorimotor Control Research Group, Max Planck Institute of Neurobiology, 82152 Martinsried, Germany; (Y.K.W.); (R.P.)
- Institute of Neuroscience, Technical University of Munich, 80802 Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Oksana M. Subach
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, 123182 Moscow, Russia; (O.M.S.); (V.V.P.); (A.V.V.); (D.A.K.); (A.Y.N.); (T.V.R.)
| | - Elizaveta S. Chefanova
- Department of NBIC-technologies, Moscow Institute of Physics and Technology, 123182 Moscow, Russia;
| | - Viktor V. Plusnin
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, 123182 Moscow, Russia; (O.M.S.); (V.V.P.); (A.V.V.); (D.A.K.); (A.Y.N.); (T.V.R.)
- Department of NBIC-technologies, Moscow Institute of Physics and Technology, 123182 Moscow, Russia;
| | - Olga I. Ivashkina
- Laboratory for Neurobiology of Memory, P.K. Anokhin Research Institute of Normal Physiology, 125315 Moscow, Russia; (N.V.B.); (O.I.I.); (K.V.A.)
- Institute for Advanced Brain Studies, M.V. Lomonosov Moscow State University, 119991 Moscow, Russia; (V.P.S.); (A.M.G.)
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, 123182 Moscow, Russia; (O.M.S.); (V.V.P.); (A.V.V.); (D.A.K.); (A.Y.N.); (T.V.R.)
| | - Konstantin V. Anokhin
- Laboratory for Neurobiology of Memory, P.K. Anokhin Research Institute of Normal Physiology, 125315 Moscow, Russia; (N.V.B.); (O.I.I.); (K.V.A.)
- Institute for Advanced Brain Studies, M.V. Lomonosov Moscow State University, 119991 Moscow, Russia; (V.P.S.); (A.M.G.)
| | - Anna V. Vlaskina
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, 123182 Moscow, Russia; (O.M.S.); (V.V.P.); (A.V.V.); (D.A.K.); (A.Y.N.); (T.V.R.)
| | - Dmitry A. Korzhenevskiy
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, 123182 Moscow, Russia; (O.M.S.); (V.V.P.); (A.V.V.); (D.A.K.); (A.Y.N.); (T.V.R.)
| | - Alena Y. Nikolaeva
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, 123182 Moscow, Russia; (O.M.S.); (V.V.P.); (A.V.V.); (D.A.K.); (A.Y.N.); (T.V.R.)
| | - Konstantin M. Boyko
- Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, 119071 Moscow, Russia;
| | - Tatiana V. Rakitina
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, 123182 Moscow, Russia; (O.M.S.); (V.V.P.); (A.V.V.); (D.A.K.); (A.Y.N.); (T.V.R.)
- Laboratory of Hormonal Regulation Proteins, M.M. Shemyakin and Yu.A. Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, 117997 Moscow, Russia
| | - Anna M. Varizhuk
- Department of Biophysics, Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, 119435 Moscow, Russia; (A.M.V.); (G.E.P.)
- Department of Biophysics, Center for Precision Genome Editing and Genetic Technologies for Biomedicine, 119435 Moscow, Russia
| | - Galina E. Pozmogova
- Department of Biophysics, Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, 119435 Moscow, Russia; (A.M.V.); (G.E.P.)
- Department of Biophysics, Center for Precision Genome Editing and Genetic Technologies for Biomedicine, 119435 Moscow, Russia
| | - Fedor V. Subach
- Complex of NBICS Technologies, National Research Center “Kurchatov Institute”, 123182 Moscow, Russia; (O.M.S.); (V.V.P.); (A.V.V.); (D.A.K.); (A.Y.N.); (T.V.R.)
- Correspondence: ; Tel.: +07-499-196-7100-3389
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