1
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Wang BL, Zeng P, Jiang C, Chen Y, Qu J, Song J. Aromatic Alcohol-Based pH-Sensitive Chromophore with a Unique Near-Infrared Dual-Band Solvatochromic Property and Its Application as a Ratiometric Fluorescent Sensor for G-Quadruplexes. Anal Chem 2024; 96:6186-6194. [PMID: 38594223 DOI: 10.1021/acs.analchem.3c05104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Solvatochromes have gained great attention because of their unique roles in monitoring biomolecular location, interaction, and dynamics. Particularly, solvatochromes presenting both red-shifting excitation and dual-band switchable emission are in great demand yet significantly difficult to come true. In this article, we disclose an aromatic alcohol-based pH-sensitive chromophore NIR-HBT that not only presents red-shifting excitation and solvent-dependent dual-band emission but also shows high photostability and excellent brightness. To the best of our knowledge, this is the first solvatochrome to simultaneously display these optical properties. Especially, in contrast to the reported dual-band solvatochromes whose solvatochromism is achieved by affecting their excited state behaviors, the solvatochromism of NIR-HBT is realized by modulating its ground state proton dissociation, which is a new solvatochromic mechanism that has not been reported. Furthermore, based on the dual-band solvatochromism of NIR-HBT and its intrinsic binding ability to GQs, near-infrared ratiometric detection of GQs is achieved. These results indicate that NIR-HBT is an attractive solvatochrome that can be used to develop near-infrared ratiometric biosensors for biological research. More broadly, the discovered solvatochromic mechanism can also open new horizons for exploring the solvatochrome.
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Affiliation(s)
- Bo-Lin Wang
- State Key Laboratory of Radio Frequency Heterogeneous Integration (Shenzhen University); College of Physics and Optoelectronic Engineering, Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, Shenzhen University, Shenzhen 518060, P. R. China
| | - Pengju Zeng
- State Key Laboratory of Radio Frequency Heterogeneous Integration (Shenzhen University); College of Physics and Optoelectronic Engineering, Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, Shenzhen University, Shenzhen 518060, P. R. China
| | - Chuang Jiang
- College of Chemistry, Sichuan University, No. 29 Wangjiang Road, Chengdu 610064, China
| | - Yu Chen
- State Key Laboratory of Radio Frequency Heterogeneous Integration (Shenzhen University); College of Physics and Optoelectronic Engineering, Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, Shenzhen University, Shenzhen 518060, P. R. China
- Medical Engineering and Technology College, Xinjiang Medical University, Urumqi 830011, P. R. China
| | - Junle Qu
- State Key Laboratory of Radio Frequency Heterogeneous Integration (Shenzhen University); College of Physics and Optoelectronic Engineering, Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, Shenzhen University, Shenzhen 518060, P. R. China
- Medical Engineering and Technology College, Xinjiang Medical University, Urumqi 830011, P. R. China
| | - Jun Song
- State Key Laboratory of Radio Frequency Heterogeneous Integration (Shenzhen University); College of Physics and Optoelectronic Engineering, Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, Shenzhen University, Shenzhen 518060, P. R. China
- Medical Engineering and Technology College, Xinjiang Medical University, Urumqi 830011, P. R. China
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2
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Mehl BP, Vairaprakash P, Li L, Hinde E, MacNevin CJ, Hsu CW, Gratton E, Liu B, Hahn KM. Live-cell biosensors based on the fluorescence lifetime of environment-sensing dyes. CELL REPORTS METHODS 2024; 4:100734. [PMID: 38503289 PMCID: PMC10985238 DOI: 10.1016/j.crmeth.2024.100734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 03/13/2023] [Accepted: 02/26/2024] [Indexed: 03/21/2024]
Abstract
In this work, we examine the use of environment-sensitive fluorescent dyes in fluorescence lifetime imaging microscopy (FLIM) biosensors. We screened merocyanine dyes to find an optimal combination of environment-induced lifetime changes, photostability, and brightness at wavelengths suitable for live-cell imaging. FLIM was used to monitor a biosensor reporting conformational changes of endogenous Cdc42 in living cells. The ability to quantify activity using phasor analysis of a single fluorophore (e.g., rather than ratio imaging) eliminated potential artifacts. We leveraged these properties to determine specific concentrations of activated Cdc42 across the cell.
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Affiliation(s)
- Brian P Mehl
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Pothiappan Vairaprakash
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Li Li
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Elizabeth Hinde
- Laboratory for Fluorescence Dynamics, Department of Biomedical Engineering, University of California at Irvine, Irvine, CA 92617, USA
| | - Christopher J MacNevin
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Chia-Wen Hsu
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Enrico Gratton
- Laboratory for Fluorescence Dynamics, Department of Biomedical Engineering, University of California at Irvine, Irvine, CA 92617, USA
| | - Bei Liu
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
| | - Klaus M Hahn
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
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3
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Hladyshau S, Stoop JP, Kamada K, Nie S, Tsygankov D. Spatiotemporal Coordination of Rac1 and Cdc42 at the Whole Cell Level during Cell Ruffling. Cells 2023; 12:1638. [PMID: 37371108 DOI: 10.3390/cells12121638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 06/06/2023] [Accepted: 06/09/2023] [Indexed: 06/29/2023] Open
Abstract
Rho-GTPases are central regulators within a complex signaling network that controls cytoskeletal organization and cell movement. The network includes multiple GTPases, such as the most studied Rac1, Cdc42, and RhoA, along with their numerous effectors that provide mutual regulation through feedback loops. Here we investigate the temporal and spatial relationship between Rac1 and Cdc42 during membrane ruffling, using a simulation model that couples GTPase signaling with cell morphodynamics and captures the GTPase behavior observed with FRET-based biosensors. We show that membrane velocity is regulated by the kinetic rate of GTPase activation rather than the concentration of active GTPase. Our model captures both uniform and polarized ruffling. We also show that cell-type specific time delays between Rac1 and Cdc42 activation can be reproduced with a single signaling motif, in which the delay is controlled by feedback from Cdc42 to Rac1. The resolution of our simulation output matches those of time-lapsed recordings of cell dynamics and GTPase activity. Our data-driven modeling approach allows us to validate simulation results with quantitative precision using the same pipeline for the analysis of simulated and experimental data.
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Affiliation(s)
- Siarhei Hladyshau
- School of Biology, Georgia Institute of Technology, Atlanta, GA 30332, USA
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA 30332, USA
| | - Jorik P Stoop
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA 30332, USA
| | - Kosei Kamada
- Faculty of Medicine, The University of Tokyo, Tokyo 113-8654, Japan
| | - Shuyi Nie
- School of Biology, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Denis Tsygankov
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA 30332, USA
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4
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Hladyshau S, Stoop JP, Kamada K, Nie S, Tsygankov DV. Spatiotemporal coordination of Rac1 and Cdc42 at the whole cell level during cell ruffling. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.31.535147. [PMID: 37034645 PMCID: PMC10081307 DOI: 10.1101/2023.03.31.535147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Rho-GTPases are central regulators within a complex signaling network that controls the cytoskeletal organization and cell movement. This network includes multiple GTPases, such as the most studied Rac1, Cdc42, and RhoA, and their numerous effectors that provide mutual regulation and feedback loops. Here we investigate the temporal and spatial relationship between Rac1 and Cdc42 during membrane ruffling using a simulation model which couples GTPase signaling with cell morphodynamics to capture the GTPase behavior observed with FRET-based biosensors. We show that membrane velocity is regulated by the kinetic rate of GTPase activation rather than the concentration of active GTPase. Our model captures both uniform and polarized ruffling. We also show that cell-type specific time delays between Rac1 and Cdc42 activation can be reproduced with a single signaling motif, in which the delay is controlled by feedback from Cdc42 to Rac1. The resolution of our simulation output matches those of the time-lapsed recordings of cell dynamics and GTPase activity. This approach allows us to validate simulation results with quantitative precision using the same pipeline for the analysis of simulated and experimental data.
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5
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Usama SM, Caldwell DR, Shrestha P, Luciano MP, Patel NL, Kalen JD, Ivanic J, Schnermann MJ. Modified norcyanines enable ratiometric pH imaging beyond 1000 nm. Biosens Bioelectron 2022; 217:114610. [PMID: 36137483 PMCID: PMC9555292 DOI: 10.1016/j.bios.2022.114610] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 07/26/2022] [Accepted: 07/28/2022] [Indexed: 02/06/2023]
Abstract
Activatable fluorophores with emission beyond 1000 nm have the potential to enable high contrast imaging in complex in vivo settings. However, there are few scaffolds that can be applied to this challenge. Here we detail the synthesis and evaluation of benzo[c,d]indole-substituted norcyanines that enable pH responsive fluorescence imaging in the long wavelength (>1150 nm) range. A key component of our molecular design is the installation of a hydrophilic substituted quaternary amine in the central dihydropyridine ring system. A compound with a C4'-phenyl substituent, but not the C4'-protio homologue, exhibits absorbance maxima of 740 nm and 1130 nm in basic and acidic media, respectively, with evidence of J-aggregate-like properties. These two distinct absorbances enabled ratiometric imaging of probe internalization in a tumor model. Overall, these studies provide a new class of activatable long-wavelength responsive fluorophores with promising photophysical properties.
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Affiliation(s)
- Syed Muhammad Usama
- Chemical Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD, 21702, United States
| | - Donald R Caldwell
- Chemical Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD, 21702, United States
| | - Pradeep Shrestha
- Chemical Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD, 21702, United States
| | - Michael P Luciano
- Chemical Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD, 21702, United States
| | - Nimit L Patel
- Small Animal Imaging Program, Frederick National Laboratory for Cancer Research, Leidos Biomedical Research Inc, Frederick, MD, 21702, United States
| | - Joseph D Kalen
- Small Animal Imaging Program, Frederick National Laboratory for Cancer Research, Leidos Biomedical Research Inc, Frederick, MD, 21702, United States
| | - Joseph Ivanic
- Advanced Biomedical Computational Science, Frederick National Laboratory for Cancer Research, Leidos Biomedical Research Inc, Frederick, MD, 21702, United States
| | - Martin J Schnermann
- Chemical Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD, 21702, United States.
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6
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Wolff DW, Deng Z, Bianchi-Smiraglia A, Foley CE, Han Z, Wang X, Shen S, Rosenberg MM, Moparthy S, Yun DH, Chen J, Baker BK, Roll MV, Magiera AJ, Li J, Hurley E, Feltri ML, Cox AO, Lee J, Furdui CM, Liu L, Bshara W, LaConte LE, Kandel ES, Pasquale EB, Qu J, Hedstrom L, Nikiforov MA. Phosphorylation of guanosine monophosphate reductase triggers a GTP-dependent switch from pro- to anti-oncogenic function of EPHA4. Cell Chem Biol 2022; 29:970-984.e6. [PMID: 35148834 PMCID: PMC9620470 DOI: 10.1016/j.chembiol.2022.01.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 11/19/2021] [Accepted: 01/11/2022] [Indexed: 12/11/2022]
Abstract
Signal transduction pathways post-translationally regulating nucleotide metabolism remain largely unknown. Guanosine monophosphate reductase (GMPR) is a nucleotide metabolism enzyme that decreases GTP pools by converting GMP to IMP. We observed that phosphorylation of GMPR at Tyr267 is critical for its activity and found that this phosphorylation by ephrin receptor tyrosine kinase EPHA4 decreases GTP pools in cell protrusions and levels of GTP-bound RAC1. EPHs possess oncogenic and tumor-suppressor activities, although the mechanisms underlying switches between these two modes are poorly understood. We demonstrated that GMPR plays a key role in EPHA4-mediated RAC1 suppression. This supersedes GMPR-independent activation of RAC1 by EPHA4, resulting in a negative overall effect on melanoma cell invasion and tumorigenicity. Accordingly, EPHA4 levels increase during melanoma progression and inversely correlate with GMPR levels in individual melanoma tumors. Therefore, phosphorylation of GMPR at Tyr267 is a metabolic signal transduction switch controlling GTP biosynthesis and transformed phenotypes.
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Affiliation(s)
- David W. Wolff
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA,Department of Cancer Biology, Wake Forest School of Medicine, Winston Salem, NC 27157, USA
| | - Zhiyong Deng
- Department of Cancer Biology, Wake Forest School of Medicine, Winston Salem, NC 27157, USA
| | - Anna Bianchi-Smiraglia
- Department of Cell Stress Biology, Roswell Park Comprehensive Cancer Center, Buffalo, NY 14203, USA
| | - Colleen E. Foley
- Department of Cell Stress Biology, Roswell Park Comprehensive Cancer Center, Buffalo, NY 14203, USA
| | - Zhannan Han
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA,Department of Cancer Biology, Wake Forest School of Medicine, Winston Salem, NC 27157, USA
| | - Xingyou Wang
- Department of Chemistry, Brandeis University, Waltham, MA 02453, USA
| | - Shichen Shen
- Department of Pharmaceutical Sciences, University at Buffalo, Buffalo, NY 14214, USA
| | | | - Sudha Moparthy
- Department of Cancer Biology, Wake Forest School of Medicine, Winston Salem, NC 27157, USA
| | - Dong Hyun Yun
- Department of Cancer Biology, Wake Forest School of Medicine, Winston Salem, NC 27157, USA
| | - Jialin Chen
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA,Department of Cancer Biology, Wake Forest School of Medicine, Winston Salem, NC 27157, USA
| | - Brian K. Baker
- Department of Cancer Biology, Wake Forest School of Medicine, Winston Salem, NC 27157, USA
| | - Matthew V. Roll
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA,Department of Cancer Biology, Wake Forest School of Medicine, Winston Salem, NC 27157, USA
| | - Andrew J. Magiera
- Department of Cancer Biology, Wake Forest School of Medicine, Winston Salem, NC 27157, USA
| | - Jun Li
- Department of Pharmaceutical Sciences, University at Buffalo, Buffalo, NY 14214, USA
| | - Edward Hurley
- Department of Biochemistry and Neurology, Hunter James Kelly Research Institute, University at Buffalo, Buffalo NY, USA
| | - Maria Laura Feltri
- Department of Biochemistry and Neurology, Hunter James Kelly Research Institute, University at Buffalo, Buffalo NY, USA
| | - Anderson O. Cox
- Department of Internal Medicine, Section of Molecular Medicine, Wake Forest School of Medicine, Winston-Salem NC, USA
| | - Jingyun Lee
- Department of Internal Medicine, Section of Molecular Medicine, Wake Forest School of Medicine, Winston-Salem NC, USA
| | - Cristina M. Furdui
- Department of Internal Medicine, Section of Molecular Medicine, Wake Forest School of Medicine, Winston-Salem NC, USA
| | - Liang Liu
- Department of Cancer Biology, Wake Forest School of Medicine, Winston Salem, NC 27157, USA
| | - Wiam Bshara
- Department of Pathology, Roswell Park Comprehensive Cancer Center, Buffalo NY 14203, USA
| | - Leslie E.W. LaConte
- Fralin Biomedical Research Institute at Virginia Tech Carilion School of Medicine, Roanoke, VA 24016, USA
| | - Eugene S. Kandel
- Department of Cell Stress Biology, Roswell Park Comprehensive Cancer Center, Buffalo, NY 14203, USA
| | - Elena B. Pasquale
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Jun Qu
- Department of Chemistry, Brandeis University, Waltham, MA 02453, USA
| | - Lizbeth Hedstrom
- Department of Chemistry, Brandeis University, Waltham, MA 02453, USA,Department of Biology, Brandeis University, Waltham, MA 02453, USA
| | - Mikhail A. Nikiforov
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA,Department of Cancer Biology, Wake Forest School of Medicine, Winston Salem, NC 27157, USA,Department of Pathology, Duke University School of Medicine, Durham, NC 27710, USA,Corresponding author and lead contact: Mikhail A. Nikiforov,
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7
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Wu YW. Spatiotemporal Imaging of Small GTPase Activity Using Conformational Sensors for GTPase Activity (COSGA). METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2021; 2262:259-267. [PMID: 33977482 DOI: 10.1007/978-1-0716-1190-6_15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Small GTPases cycle between active GTP bound and inactive GDP bound forms in live cells. They act as molecular switches and regulate diverse cellular processes at different times and locations in the cell. Spatiotemporal visualization of their activity provides important insights into dynamics of cellular signaling. Conformational sensors for GTPase activity (COSGAs) are based on the conserved GTPase fold and have been used as a versatile approach for imaging small GTPase activity in the cell. Conformational changes upon GDP/GTP binding can be visualized directly in solution, on beads, or in live cells using COSGA by fluorescence lifetime imaging microscopy (FLIM) technique. Herein, we describe the construction of COSGA for imaging K-Ras GTPase activity in live cells.
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Affiliation(s)
- Yao-Wen Wu
- Department of Chemistry, Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden.
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8
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Bai Y, Wan W, Huang Y, Jin W, Lyu H, Xia Q, Dong X, Gao Z, Liu Y. Quantitative interrogation of protein co-aggregation using multi-color fluorogenic protein aggregation sensors. Chem Sci 2021; 12:8468-8476. [PMID: 34221329 PMCID: PMC8221170 DOI: 10.1039/d1sc01122g] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 05/19/2021] [Indexed: 12/27/2022] Open
Abstract
Co-aggregation of multiple pathogenic proteins is common in neurodegenerative diseases but deconvolution of such biochemical process is challenging. Herein, we developed a dual-color fluorogenic thermal shift assay to simultaneously report on the aggregation of two different proteins and quantitatively study their thermodynamic stability during co-aggregation. Expansion of spectral coverage was first achieved by developing multi-color fluorogenic protein aggregation sensors. Orthogonal detection was enabled by conjugating sensors of minimal fluorescence crosstalk to two different proteins via sortase-tag technology. Using this assay, we quantified shifts in melting temperatures in a heterozygous model protein system, revealing that the thermodynamic stability of wild-type proteins was significantly compromised by the mutant ones but not vice versa. We also examined how small molecule ligands selectively and differentially interfere with such interplay. Finally, we demonstrated these sensors are suited to visualize how different proteins exert influence on each other upon their co-aggregation in live cells.
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Affiliation(s)
- Yulong Bai
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences 457 Zhongshan Road Dalian 116023 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Wang Wan
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences 457 Zhongshan Road Dalian 116023 China
| | - Yanan Huang
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences 457 Zhongshan Road Dalian 116023 China
| | - Wenhan Jin
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences 457 Zhongshan Road Dalian 116023 China
| | - Haochen Lyu
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences 457 Zhongshan Road Dalian 116023 China
| | - Qiuxuan Xia
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences 457 Zhongshan Road Dalian 116023 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Xuepeng Dong
- The Second Hospital of Dalian Medical University 467 Zhongshan Road Dalian 116044 China
| | - Zhenming Gao
- The Second Hospital of Dalian Medical University 467 Zhongshan Road Dalian 116044 China
| | - Yu Liu
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences 457 Zhongshan Road Dalian 116023 China
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9
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Bonanno A, Pérez-Herráez I, Zaballos-García E, Pérez-Prieto J. Gold nanoclusters for ratiometric sensing of pH in extremely acidic media. Chem Commun (Camb) 2020; 56:587-590. [DOI: 10.1039/c9cc08539d] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
AuNCs capped with β-nicotinamide adenine dinucleotide phosphate exhibit an outstanding performance as ratiometric, fluorescent pH sensors in extremely acid media (0.6–2.7) and in the 7.0–9.2 pH range; the nanocluster itself is the fluorophore.
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Affiliation(s)
- Adele Bonanno
- Departamento de Química Orgánica
- Universidad de Valencia
- Av. Vicent Andres Estelles s/n
- Burjassot
- Spain
| | - Irene Pérez-Herráez
- Instituto de Ciencia Molecular (ICMol)
- Universidad de Valencia
- Catedrático José Beltrán 2
- Valencia
- Spain
| | - Elena Zaballos-García
- Departamento de Química Orgánica
- Universidad de Valencia
- Av. Vicent Andres Estelles s/n
- Burjassot
- Spain
| | - Julia Pérez-Prieto
- Instituto de Ciencia Molecular (ICMol)
- Universidad de Valencia
- Catedrático José Beltrán 2
- Valencia
- Spain
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10
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Yokoo H, Kagechika H, Ohsaki A, Hirano T. A Polarity‐Sensitive Fluorescent Amino Acid and its Incorporation into Peptides for the Ratiometric Detection of Biomolecular Interactions. Chempluschem 2019; 84:1716-1719. [DOI: 10.1002/cplu.201900489] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 10/04/2019] [Indexed: 12/27/2022]
Affiliation(s)
- Hidetomo Yokoo
- Institute of Biomaterials and BioengineeringTokyo Medical and Dental University (TMDU) 2-3-10 Kanda-Surugadai, Chiyoda-ku Tokyo 101-0062 Japan
| | - Hiroyuki Kagechika
- Institute of Biomaterials and BioengineeringTokyo Medical and Dental University (TMDU) 2-3-10 Kanda-Surugadai, Chiyoda-ku Tokyo 101-0062 Japan
| | - Ayumi Ohsaki
- College of Humanities and SciencesNihon University 3-25-40 Sakurajosui, Setagaya-ku Tokyo 156-8550 Japan
| | - Tomoya Hirano
- Osaka University of Pharmaceutical Sciences 4-20-1 Nasahara, Takatsuki Osaka 569-1094 Japan
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11
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Jin H, Jin Q, Liang Z, Liu Y, Qu X, Sun Q. Quantum Dot Based Fluorescent Traffic Light Nanoprobe for Specific Imaging of Avidin-Type Biotin Receptor and Differentiation of Cancer Cells. Anal Chem 2019; 91:8958-8965. [PMID: 31251580 DOI: 10.1021/acs.analchem.9b00924] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Sensitive and specific visualization of cell surface biotin receptors (BRs) a class of clinically important biomarkers, remains a challenge. In this work, a dual-emission ratiometric fluorescent nanoprobe is developed for specific imaging of cell surface avidin, a subtype of BRs. The nanoprobe comprises a dual-emission quantum dot nanohybrid, wherein a silica-encapsulated red-emitting QD (rQD@SiO2) is used as the "core" and green-emitting QDs (gQDs) are used as "satellites", which are further decorated with a new "love-hate"-type BR ligand, a phenanthroline-biotin conjugate with an amino linker. The nanoprobe shows intense rQD emission but quenched gQD emission by the BR ligand. Upon imaging, the rQD emission stays constant and the gQD emission is restored as cell surface avidin accrues. Accordingly, the overlaid fluorescence color collected from red and green emission changes from red to yellow and then to green. We refer to such a color change as a traffic light pattern and the nanoprobe as a fluorescent traffic light nanoprobe. We demonstrate the application of our fluorescent traffic light nanoprobe to characterize cancer cells. By the traffic light pattern, cervical carcinoma and normal cells, as well as different-type cancer cells including BR-negative colon cancer cells, BR-positive hepatoma carcinoma cells, breast cancer cells, and their subtypes, have been visually differentiated. We further demonstrate a use of our nanoprobe to distinguish the G2 phase from other stages in a cell cycle. These applications provide new insights into visualizing cell surface biomarkers with remarkable imaging resolution and accuracy.
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Affiliation(s)
- Haojun Jin
- State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering , Southeast University , Nanjing 210096 , People's Republic of China
| | - Qian Jin
- State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering , Southeast University , Nanjing 210096 , People's Republic of China
| | - Zhenghui Liang
- State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering , Southeast University , Nanjing 210096 , People's Republic of China
| | - Yuqian Liu
- State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering , Southeast University , Nanjing 210096 , People's Republic of China
| | - Xiaojun Qu
- State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering , Southeast University , Nanjing 210096 , People's Republic of China
| | - Qingjiang Sun
- State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering , Southeast University , Nanjing 210096 , People's Republic of China
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12
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MacNevin CJ, Watanabe T, Weitzman M, Gulyani A, Fuehrer S, Pinkin NK, Tian X, Liu F, Jin J, Hahn KM. Membrane-Permeant, Environment-Sensitive Dyes Generate Biosensors within Living Cells. J Am Chem Soc 2019; 141:7275-7282. [PMID: 30994345 DOI: 10.1021/jacs.8b09841] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Dyes with environment-sensitive fluorescence have proven useful to study the spatiotemporal dynamics of protein activity in living cells. When attached to proteins, their fluorescence can reflect protein conformational changes, post-translational modifications, or protein interactions. However, the utility of such dye-protein conjugates has been limited because it is difficult to load them into cells. They usually must be introduced using techniques that perturb cell physiology, limit throughput, or generate fluorescent vesicles (e.g., electroporation, microinjection, or membrane transduction peptides). Here we circumvent these problems by modifying a proven, environment-sensitive biosensor fluorophore so that it can pass through cell membranes without staining intracellular compartments and can be attached to proteins within living cells using unnatural amino acid (UAA) mutagenesis. Reactive groups were incorporated for attachment to UAAs or small molecules (mero166, azide; mero167, alkyne; mero76, carboxylic acid). These dyes are bright and fluoresce at long wavelengths (reaching ε = 100 000 M-1 cm-1, ϕ = 0.24, with excitation 565 nm and emission 594 nm). The utility of mero166 was demonstrated by in-cell labeling of a UAA to generate a biosensor for the small GTPase Cdc42. In addition, conjugation of mero166 to a small molecule produced a membrane-permeable probe that reported the localization of the DNA methyltransferase G9a in cells. This approach provides a strategy to access biosensors for many targets and to more practically harness the varied environmental sensitivities of synthetic dyes.
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Affiliation(s)
- Christopher J MacNevin
- Department of Pharmacology, School of Medicine , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Takashi Watanabe
- Department of Pharmacology, School of Medicine , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Matthew Weitzman
- Department of Pharmacology, School of Medicine , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Akash Gulyani
- Department of Pharmacology, School of Medicine , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Sheryl Fuehrer
- Department of Pharmacology, School of Medicine , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Nicholas K Pinkin
- Department of Pharmacology, School of Medicine , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Xu Tian
- Department of Pharmacology, School of Medicine , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Feng Liu
- Center for Integrative Chemical Biology and Drug Discovery, School of Pharmacy , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Jian Jin
- Center for Integrative Chemical Biology and Drug Discovery, School of Pharmacy , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Klaus M Hahn
- Department of Pharmacology, School of Medicine , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
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13
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Juettner VV, Kruse K, Dan A, Vu VH, Khan Y, Le J, Leckband D, Komarova Y, Malik AB. VE-PTP stabilizes VE-cadherin junctions and the endothelial barrier via a phosphatase-independent mechanism. J Cell Biol 2019; 218:1725-1742. [PMID: 30948425 PMCID: PMC6504901 DOI: 10.1083/jcb.201807210] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 12/20/2018] [Accepted: 03/12/2019] [Indexed: 12/16/2022] Open
Abstract
Juettner et al. describe a novel phosphatase-activity–independent mechanism by which the phosphatase VE-PTP restricts endothelial permeability. VE-PTP functions as a scaffold that binds and inhibits the RhoGEF GEF-H1, limiting RhoA-dependent tension across VE-cadherin junctions and decreasing VE-cadherin internalization to stabilize adherens junctions and reduce endothelial permeability. Vascular endothelial (VE) protein tyrosine phosphatase (PTP) is an endothelial-specific phosphatase that stabilizes VE-cadherin junctions. Although studies have focused on the role of VE-PTP in dephosphorylating VE-cadherin in the activated endothelium, little is known of VE-PTP’s role in the quiescent endothelial monolayer. Here, we used the photoconvertible fluorescent protein VE-cadherin-Dendra2 to monitor VE-cadherin dynamics at adherens junctions (AJs) in confluent endothelial monolayers. We discovered that VE-PTP stabilizes VE-cadherin junctions by reducing the rate of VE-cadherin internalization independently of its phosphatase activity. VE-PTP serves as an adaptor protein that through binding and inhibiting the RhoGEF GEF-H1 modulates RhoA activity and tension across VE-cadherin junctions. Overexpression of the VE-PTP cytosolic domain mutant interacting with GEF-H1 in VE-PTP–depleted endothelial cells reduced GEF-H1 activity and restored VE-cadherin dynamics at AJs. Thus, VE-PTP stabilizes VE-cadherin junctions and restricts endothelial permeability by inhibiting GEF-H1, thereby limiting RhoA signaling at AJs and reducing the VE-cadherin internalization rate.
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Affiliation(s)
- Vanessa V Juettner
- Department of Pharmacology and the Center for Lung and Vascular Biology, The University of Illinois College of Medicine, Chicago, IL
| | - Kevin Kruse
- Department of Pharmacology and the Center for Lung and Vascular Biology, The University of Illinois College of Medicine, Chicago, IL
| | - Arkaprava Dan
- Department of Chemical and Biomolecular Engineering, University of Illinois College of Engineering at Urbana-Champaign, Urbana, IL
| | - Vinh H Vu
- Department of Chemical and Biomolecular Engineering, University of Illinois College of Engineering at Urbana-Champaign, Urbana, IL
| | - Yousaf Khan
- Department of Pharmacology and the Center for Lung and Vascular Biology, The University of Illinois College of Medicine, Chicago, IL
| | - Jonathan Le
- Department of Pharmacology and the Center for Lung and Vascular Biology, The University of Illinois College of Medicine, Chicago, IL
| | - Deborah Leckband
- Department of Chemical and Biomolecular Engineering, University of Illinois College of Engineering at Urbana-Champaign, Urbana, IL
| | - Yulia Komarova
- Department of Pharmacology and the Center for Lung and Vascular Biology, The University of Illinois College of Medicine, Chicago, IL
| | - Asrar B Malik
- Department of Pharmacology and the Center for Lung and Vascular Biology, The University of Illinois College of Medicine, Chicago, IL
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14
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Kruse K, Lee QS, Sun Y, Klomp J, Yang X, Huang F, Sun MY, Zhao S, Hong Z, Vogel SM, Shin JW, Leckband DE, Tai LM, Malik AB, Komarova YA. N-cadherin signaling via Trio assembles adherens junctions to restrict endothelial permeability. J Cell Biol 2018; 218:299-316. [PMID: 30463880 PMCID: PMC6314553 DOI: 10.1083/jcb.201802076] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 06/10/2018] [Accepted: 10/25/2018] [Indexed: 01/04/2023] Open
Abstract
This work describes a role for endothelial N-cadherin in the regulation of endothelial permeability in the brain and lung. N-cadherin adhesions formed between endothelial cells and pericytes increase the abundance of VE-cadherin at adherens junctions through the RhoGEF Trio-dependent activation of RhoA and Rac1. Vascular endothelial (VE)–cadherin forms homotypic adherens junctions (AJs) in the endothelium, whereas N-cadherin forms heterotypic adhesion between endothelial cells and surrounding vascular smooth muscle cells and pericytes. Here we addressed the question whether both cadherin adhesion complexes communicate through intracellular signaling and contribute to the integrity of the endothelial barrier. We demonstrated that deletion of N-cadherin (Cdh2) in either endothelial cells or pericytes increases junctional endothelial permeability in lung and brain secondary to reduced accumulation of VE-cadherin at AJs. N-cadherin functions by increasing the rate of VE-cadherin recruitment to AJs and induces the assembly of VE-cadherin junctions. We identified the dual Rac1/RhoA Rho guanine nucleotide exchange factor (GEF) Trio as a critical component of the N-cadherin adhesion complex, which activates both Rac1 and RhoA signaling pathways at AJs. Trio GEF1-mediated Rac1 activation induces the recruitment of VE-cadherin to AJs, whereas Trio GEF2-mediated RhoA activation increases intracellular tension and reinforces Rac1 activation to promote assembly of VE-cadherin junctions and thereby establish the characteristic restrictive endothelial barrier.
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Affiliation(s)
- Kevin Kruse
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, IL
| | - Quinn S Lee
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, IL
| | - Ying Sun
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, IL
| | - Jeff Klomp
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, IL
| | - Xiaoyan Yang
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, IL
| | - Fei Huang
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, IL
| | - Mitchell Y Sun
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, IL
| | - Shuangping Zhao
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, IL
| | - Zhigang Hong
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, IL
| | - Stephen M Vogel
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, IL
| | - Jae-Won Shin
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, IL
| | - Deborah E Leckband
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL
| | - Leon M Tai
- Department of Anatomy and Cell Biology, University of Illinois College of Medicine, Chicago, IL
| | - Asrar B Malik
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, IL
| | - Yulia A Komarova
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, IL
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15
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Zhurikhina A, Qi T, Hahn KM, Elston TC, Tsygankov D. EdgeProps: A Computational Platform for Correlative Analysis of Cell Dynamics and Near-Edge Protein Activity. Methods Mol Biol 2018; 1821:47-56. [PMID: 30062404 DOI: 10.1007/978-1-4939-8612-5_4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
Developing molecular tools to visualize and control Rho GTPase signaling in living cells has been instrumental in elucidating the mechanisms of cytoskeletal reorganization and causal relationships between activation events in cell function. An indispensable part of such studies is the quantitative characterization of the spatiotemporal GTPase activity. Here we present a computational pipeline, EdgeProps, designed for comparative/correlative analysis of cell dynamics (edge velocity) and near-edge protein activity (intensity of a fluorescent signal). The tool offers a user-friendly interface with three functional modules for processing, visualization, and statistical characterization of single-cell imaging data.
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Affiliation(s)
- Anastasia Zhurikhina
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA, USA
| | - Timothy Qi
- Department of Pharmacology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Klaus M Hahn
- Department of Pharmacology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Timothy C Elston
- Department of Pharmacology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Denis Tsygankov
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA, USA.
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16
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A cell surface display fluorescent biosensor for measuring MMP14 activity in real-time. Sci Rep 2018; 8:5916. [PMID: 29651043 PMCID: PMC5897415 DOI: 10.1038/s41598-018-24080-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 03/23/2018] [Indexed: 01/16/2023] Open
Abstract
Despite numerous recent advances in imaging technologies, one continuing challenge for cell biologists and microscopists is the visualization and measurement of endogenous proteins as they function within living cells. Achieving this goal will provide a tool that investigators can use to associate cellular outcomes with the behavior and activity of many well-studied target proteins. Here, we describe the development of a plasmid-based fluorescent biosensor engineered to measure the location and activity of matrix metalloprotease-14 (MMP14). The biosensor design uses fluorogen-activating protein technology coupled with a MMP14-selective protease sequence to generate a binary, “switch-on” fluorescence reporter capable of measuring MMP14 location, activity, and temporal dynamics. The MMP14-fluorogen activating protein biosensor approach is applicable to both short and long-term imaging modalities and contains an adaptable module that can be used to study many membrane-bound proteases. This MMP14 biosensor promises to serve as a tool for the advancement of a broad range of investigations targeting MMP14 activity during cell migration in health and disease.
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17
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Grygorenko OO, Biitseva AV, Zhersh S. Amino sulfonic acids, peptidosulfonamides and other related compounds. Tetrahedron 2018. [DOI: 10.1016/j.tet.2018.01.033] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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18
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Control of astrocyte morphology by Rho GTPases. Brain Res Bull 2017; 136:44-53. [PMID: 28502648 DOI: 10.1016/j.brainresbull.2017.05.003] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 05/05/2017] [Accepted: 05/10/2017] [Indexed: 12/15/2022]
Abstract
Astrocytes modulate and support neuronal and synapse function via numerous mechanisms that often rely on diffusion of signalling molecules, ions or metabolites through extracellular space. As a consequence, the spatial arrangement and the distance between astrocyte processes and neuronal structures are of functional importance. Likewise, changes of astrocyte structure will affect the ability of astrocytes to interact with neurons. In contrast to neurons, where rapid morphology changes are critically involved in many aspects of physiological brain function, a role of astrocyte restructuring in brain physiology is only beginning to emerge. In neurons, small GTPases of the Rho family are powerful initiators and modulators of structural changes. Less is known about the functional significance of these signalling molecules in astrocytes. Here, we review recent experimental evidence for the role of RhoA, Cdc42 and Rac1 in controlling dynamic astrocyte morphology as well as experimental tools and analytical approaches for studying astrocyte morphology changes.
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19
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20
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Abstract
Physiological stimuli activate protein kinases for finite periods of time, which is critical for specific biological outcomes. Mimicking this transient biological activity of kinases is challenging due to the limitations of existing methods. Here, we report a strategy enabling transient kinase activation in living cells. Using two protein-engineering approaches, we achieve independent control of kinase activation and inactivation. We show successful regulation of tyrosine kinase c-Src (Src) and Ser/Thr kinase p38α (p38), demonstrating broad applicability of the method. By activating Src for finite periods of time, we reveal how the duration of kinase activation affects secondary morphological changes that follow transient Src activation. This approach highlights distinct roles for sequential Src-Rac1- and Src-PI3K-signaling pathways at different stages during transient Src activation. Finally, we demonstrate that this method enables transient activation of Src and p38 in a specific signaling complex, providing a tool for targeted regulation of individual signaling pathways.
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21
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Spatiotemporal imaging of small GTPases activity in live cells. Proc Natl Acad Sci U S A 2016; 113:14348-14353. [PMID: 27911813 DOI: 10.1073/pnas.1613999113] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Ras-like small GTPases function as molecular switches and regulate diverse cellular events. To examine the dynamics of signaling requires spatiotemporal visualization of their activity in the cell. Current small GTPase sensors rely on specific effector domains that are available for only a small number of GTPases and compete for endogenous regulator/effector binding. Here, we describe versatile conformational sensors for GTPase activity (COSGAs) based on the conserved GTPase fold. Conformational changes upon GDP/GTP exchange were directly observed in solution, on beads, and in live cells by Förster resonance energy transfer (FRET). The COSGAs allow for monitoring of Rab1 and K-Ras activity in live cells using fluorescence lifetime imaging microscopy. We found that Rab1 is largely active in the cytoplasm and inactive at the Golgi, suggesting that the Golgi serves as the terminal of the Rab1 functional cycle. K-Ras displays polarized activity at the plasma membrane, with less activity at the edge of the cell and membrane ruffles.
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