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Wang Y, Xiong Y, Shi K, Effah CY, Song L, He L, Liu J. DNA nanostructures for exploring cell-cell communication. Chem Soc Rev 2024; 53:4020-4044. [PMID: 38444346 DOI: 10.1039/d3cs00944k] [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: 03/07/2024]
Abstract
The process of coordinating between the same or multiple types of cells to jointly execute various instructions in a controlled and carefully regulated environment is a very appealing field. In order to provide clearer insight into the role of cell-cell interactions and the cellular communication of this process in their local communities, several interdisciplinary approaches have been employed to enhance the core understanding of this phenomenon. DNA nanostructures have emerged in recent years as one of the most promising tools in exploring cell-cell communication and interactions due to their programmability and addressability. Herein, this review is dedicated to offering a new perspective on using DNA nanostructures to explore the progress of cell-cell communication. After briefly outlining the anchoring strategy of DNA nanostructures on cell membranes and the subsequent dynamic regulation of DNA nanostructures, this paper highlights the significant contribution of DNA nanostructures in monitoring cell-cell communication and regulating its interactions. Finally, we provide a quick overview of the current challenges and potential directions for the application of DNA nanostructures in cellular communication and interactions.
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Affiliation(s)
- Ya Wang
- College of Public Health, Zhengzhou University, Zhengzhou 450001, China.
| | - Yamin Xiong
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, China
| | - Kangqi Shi
- College of Public Health, Zhengzhou University, Zhengzhou 450001, China.
| | - Clement Yaw Effah
- The First Affiliated Hospital of Zhengzhou University, Henan Key Laboratory of Critical Care Medicine, Zhengzhou Key Laboratory of Sepsis, Henan Engineering Research Center for Critical Care Medicine, Zhengzhou 450003, China
| | - Lulu Song
- College of Public Health, Zhengzhou University, Zhengzhou 450001, China.
| | - Leiliang He
- College of Public Health, Zhengzhou University, Zhengzhou 450001, China.
| | - Jianbo Liu
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Key Laboratory for Bio-Nanotechnology and Molecular Engineering of Hunan Province, Hunan University, Changsha 410082, China.
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Peracchia C. Gap Junction Channel Regulation: A Tale of Two Gates-Voltage Sensitivity of the Chemical Gate and Chemical Sensitivity of the Fast Voltage Gate. Int J Mol Sci 2024; 25:982. [PMID: 38256055 PMCID: PMC10815820 DOI: 10.3390/ijms25020982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 01/08/2024] [Accepted: 01/10/2024] [Indexed: 01/24/2024] Open
Abstract
Gap junction channels are regulated by gates sensitive to cytosolic acidification and trans-junctional voltage (Vj). We propose that the chemical gate is a calmodulin (CaM) lobe. The fast-Vj gate is made primarily by the connexin's NH2-terminus domain (NT). The chemical gate closes the channel slowly and completely, while the fast-Vj gate closes the channel rapidly but incompletely. The chemical gate closes with increased cytosolic calcium concentration [Ca2+]i and with Vj gradients at Vj's negative side. In contrast, the fast-Vj gate closes at the positive or negative side of Vj depending on the connexin (Cx) type. Cxs with positively charged NT close at Vj's negative side, while those with negatively charged NT close at Vj's positive side. Cytosolic acidification alters in opposite ways the sensitivity of the fast-Vj gate: it increases the Vj sensitivity of negative gaters and decreases that of positive gaters. While the fast-Vj gate closes and opens instantaneously, the chemical gate often shows fluctuations, likely to reflect the shifting of the gate (CaM's N-lobe) in and out of the channel's pore.
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Affiliation(s)
- Camillo Peracchia
- Department of Pharmacology and Physiology, School of Medicine and Dentistry, University Rochester, Rochester, NY 14642-8711, USA
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3
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Iyer AR, Sheeba V. A new player in circadian networks: Role of electrical synapses in regulating functions of the circadian clock. Front Physiol 2022; 13:968574. [PMID: 36406999 PMCID: PMC9669436 DOI: 10.3389/fphys.2022.968574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 10/19/2022] [Indexed: 11/06/2022] Open
Abstract
Several studies have indicated that coherent circadian rhythms in behaviour can be manifested only when the underlying circadian oscillators function as a well-coupled network. The current literature suggests that circadian pacemaker neuronal networks rely heavily on communication mediated by chemical synapses comprising neuropeptides and neurotransmitters to regulate several behaviours and physiological processes. It has become increasingly clear that chemical synapses closely interact with electrical synapses and function together in the neuronal networks of most organisms. However, there are only a few studies which have examined the role of electrical synapses in circadian networks and here, we review our current understanding of gap junction proteins in circadian networks of various model systems. We describe the general mechanisms by which electrical synapses function in neural networks, their interactions with chemical neuromodulators and their contributions to the regulation of circadian rhythms. We also discuss the various methods available to characterize functional electrical synapses in these networks and the potential directions that remain to be explored to understand the roles of this relatively understudied mechanism of communication in modulating circadian behaviour.
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Affiliation(s)
- Aishwarya Ramakrishnan Iyer
- Chronobiology and Behavioural Neurogenetics Laboratory, Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka, India
- Department of Neuroscience and Behavior, Barnard College of Columbia University, New York, NY, United States
| | - Vasu Sheeba
- Chronobiology and Behavioural Neurogenetics Laboratory, Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka, India
- *Correspondence: Vasu Sheeba,
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Peracchia C, Leverone Peracchia LM. Calmodulin-Connexin Partnership in Gap Junction Channel Regulation-Calmodulin-Cork Gating Model. Int J Mol Sci 2021; 22:ijms222313055. [PMID: 34884859 PMCID: PMC8658047 DOI: 10.3390/ijms222313055] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 11/27/2021] [Accepted: 11/29/2021] [Indexed: 01/19/2023] Open
Abstract
In the past four decades numerous findings have indicated that gap junction channel gating is mediated by intracellular calcium concentrations ([Ca2+i]) in the high nanomolar range via calmodulin (CaM). We have proposed a CaM-based gating model based on evidence for a direct CaM role in gating. This model is based on the following: CaM inhibitors and the inhibition of CaM expression to prevent chemical gating. A CaM mutant with higher Ca2+ sensitivity greatly increases gating sensitivity. CaM co-localizes with connexins. Connexins have high-affinity CaM-binding sites. Connexin mutants paired to wild type connexins have a higher gating sensitivity, which is eliminated by the inhibition of CaM expression. Repeated trans-junctional voltage (Vj) pulses progressively close channels by the chemical/slow gate (CaM’s N-lobe). At the single channel level, the gate closes and opens slowly with on-off fluctuations. Internally perfused crayfish axons lose gating competency but recover it by the addition of Ca-CaM to the internal perfusion solution. X-ray diffraction data demonstrate that isolated gap junctions are gated at the cytoplasmic end by a particle of the size of a CaM lobe. We have proposed two types of CaM-driven gating: “Ca-CaM-Cork” and “CaM-Cork”. In the first, the gating involves Ca2+-induced CaM activation. In the second, the gating occurs without a [Ca2+]i rise.
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Jindal S, Chockalingam S, Ghosh SS, Packirisamy G. Connexin and gap junctions: perspectives from biology to nanotechnology based therapeutics. Transl Res 2021; 235:144-167. [PMID: 33582245 DOI: 10.1016/j.trsl.2021.02.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 01/10/2021] [Accepted: 02/09/2021] [Indexed: 12/11/2022]
Abstract
The concept of gap junctions and their role in intercellular communication has been known for around 50 years. Considerable progress has been made in understanding the fundamental biology of connexins in mediating gap junction intercellular communication (GJIC) and their role in various cellular processes including pathological conditions. However, this understanding has not led to development of advanced therapeutics utilizing GJIC. Inadequacies in strategies that target specific connexin protein in the affected tissue, with minimal or no collateral damage, are the primary reason for the lack of development of efficient therapeutic models. Herein, nanotechnology has a role to play, giving plenty of scope to circumvent these problems and develop more efficient connexin based therapeutics. AsODN, antisense oligodeoxynucleotides; BMPs, bone morphogenetic proteins; BMSCs, bone marrow stem cells; BG, bioglass; Cx, Connexin; CxRE, connexin-responsive elements; CoCr NPs, cobalt-chromium nanoparticles; cGAMP, cyclic guanosine monophosphate-adenosine monophosphate; cAMP, cyclic adenosine monophosphate; ERK1/2, extracellular signal-regulated kinase 1/2; EMT, epithelial-mesenchymal transition; EPA, eicosapentaenoic acids; FGFR1, fibroblast growth factor receptor 1; FRAP, fluorescence recovery after photobleaching; 5-FU, 5-fluorouracil; GJ, gap junction; GJIC, gap junctional intercellular communication; HGPRTase, hypoxanthine phosphoribosyltransferase; HSV-TK, herpes virus thymidine kinase; HSA, human serum albumin; HA, hyaluronic acid; HDAC, histone deacetylase; IRI, ischemia reperfusion injury; IL-6, interleukin-6; IL-8, interleukin-8; IONPs, iron-oxide nanoparticles; JNK, c-Jun N-terminal kinase; LAMP, local activation of molecular fluorescent probe; MSCs, mesenchymal stem cells; MMP, matrix metalloproteinase; MI, myocardial infarction; MAPK, mitogen-activated protein kinase; NF-κB, nuclear factor kappa B; NO, nitric oxide; PKC, protein kinase C; QDs, quantum dots; ROI, region of interest; RGO, reduced graphene oxide; siRNA, small interfering RNA; TGF-β1, transforming growth factor-β1; TNF-α, tumor necrosis factor-α; UCN, upconversion nanoparticles; VEGF, vascular endothelial growth factor. In this review, we discuss briefly the role of connexins and gap junctions in various physiological and pathological processes, with special emphasis on cancer. We further discuss the application of nanotechnology and tissue engineering in developing treatments for various connexin based disorders.
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Affiliation(s)
- Shlok Jindal
- Nanobiotechnology Laboratory, Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, India
| | - S Chockalingam
- Department of Biotechnology, National Institute of Technology Warangal, Warangal, Telangana, India
| | - Siddhartha Sankar Ghosh
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam, India
| | - Gopinath Packirisamy
- Nanobiotechnology Laboratory, Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, India; Centre for Nanotechnology, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, India.
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6
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Hou J, Zhu S, Zhao Z, Shen J, Chao J, Shi J, Li J, Wang L, Ge Z, Li Q. Programming cell communications with pH-responsive DNA nanodevices. Chem Commun (Camb) 2021; 57:4536-4539. [PMID: 33956003 DOI: 10.1039/d1cc00875g] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
DNA nanoswitches on cell surfaces could respond to changes of pH under physiological conditions by switching from a three-chain structure to a double-chain structure, thus connecting another set of cells modified with complementary single-stranded DNA. This pH-triggered cell communication offers a promising approach for cell-based therapy under a tumor microenvironment.
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Affiliation(s)
- Junjun Hou
- Division of Physical Biology, CAS Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China and University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Shitai Zhu
- Division of Physical Biology, CAS Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China and University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ziwei Zhao
- Key Laboratory for Organic Electronics & Information Displays (KLOEID), Institute of Advanced Materials (IAM) and School of Materials Science and Engineering, Nanjing University of Posts & Telecommunications, Nanjing, China
| | - Jianlei Shen
- School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, Shanghai Jiao Tong University, Shanghai 200240, China. ,
| | - Jie Chao
- Key Laboratory for Organic Electronics & Information Displays (KLOEID), Institute of Advanced Materials (IAM) and School of Materials Science and Engineering, Nanjing University of Posts & Telecommunications, Nanjing, China
| | - Jiye Shi
- Division of Physical Biology, CAS Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
| | - Jiang Li
- The Interdisciplinary Research Center, Shanghai Synchrotron Radiation Facility, Zhangjiang Laboratory, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China
| | - Lihua Wang
- Division of Physical Biology, CAS Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China and The Interdisciplinary Research Center, Shanghai Synchrotron Radiation Facility, Zhangjiang Laboratory, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China
| | - Zhilei Ge
- School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, Shanghai Jiao Tong University, Shanghai 200240, China. ,
| | - Qian Li
- School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, Shanghai Jiao Tong University, Shanghai 200240, China. ,
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7
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Boyle PM, Yu J, Klimas A, Williams JC, Trayanova NA, Entcheva E. OptoGap is an optogenetics-enabled assay for quantification of cell-cell coupling in multicellular cardiac tissue. Sci Rep 2021; 11:9310. [PMID: 33927252 PMCID: PMC8085001 DOI: 10.1038/s41598-021-88573-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 03/31/2021] [Indexed: 12/23/2022] Open
Abstract
Intercellular electrical coupling is an essential means of communication between cells. It is important to obtain quantitative knowledge of such coupling between cardiomyocytes and non-excitable cells when, for example, pathological electrical coupling between myofibroblasts and cardiomyocytes yields increased arrhythmia risk or during the integration of donor (e.g., cardiac progenitor) cells with native cardiomyocytes in cell-therapy approaches. Currently, there is no direct method for assessing heterocellular coupling within multicellular tissue. Here we demonstrate experimentally and computationally a new contactless assay for electrical coupling, OptoGap, based on selective illumination of inexcitable cells that express optogenetic actuators and optical sensing of the response of coupled excitable cells (e.g., cardiomyocytes) that are light-insensitive. Cell-cell coupling is quantified by the energy required to elicit an action potential via junctional current from the light-stimulated cell(s). The proposed technique is experimentally validated against the standard indirect approach, GapFRAP, using light-sensitive cardiac fibroblasts and non-transformed cardiomyocytes in a two-dimensional setting. Its potential applicability to the complex three-dimensional setting of the native heart is corroborated by computational modelling and proper calibration. Lastly, the sensitivity of OptoGap to intrinsic cell-scale excitability is robustly characterized via computational analysis.
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Affiliation(s)
- Patrick M Boyle
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
- Institute for Computational Medicine, Johns Hopkins University, Baltimore, MD, USA
- Department of Bioengineering, University of Washington, Seattle, WA, USA
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA, USA
- Center for Cardiovascular Biology, University of Washington, Seattle, WA, USA
| | - Jinzhu Yu
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, USA
| | - Aleksandra Klimas
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, USA
- Department of Biomedical Engineering, George Washington University, 800 22nd Street NW, Suite 5000, Washington, DC, 20052, USA
| | - John C Williams
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, USA
| | - Natalia A Trayanova
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
- Institute for Computational Medicine, Johns Hopkins University, Baltimore, MD, USA
- Alliance for Cardiovascular Diagnostic and Treatment Innovation, Johns Hopkins University, Baltimore, MD, USA
| | - Emilia Entcheva
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, USA.
- Department of Biomedical Engineering, George Washington University, 800 22nd Street NW, Suite 5000, Washington, DC, 20052, USA.
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8
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Hu Y, Zhao R, Poopal RK, Ren Z. Simultaneous eco-toxicity assessment technique using an online monitoring system: effects of different environmental factors on swimming behavior of zebrafish (Danio rerio). CHEMOSPHERE 2020; 255:126934. [PMID: 32387730 DOI: 10.1016/j.chemosphere.2020.126934] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Revised: 04/27/2020] [Accepted: 04/28/2020] [Indexed: 06/11/2023]
Abstract
Environmental factors, such as photoperiod and temperature were the main limiting factors for the survival of organisms in the nature environment. Changes in environmental factors are well predicted but determining their effects on organisms are challenging hot topic in the field of eco-toxicology. Thus, technology based eco-toxicity assessment was focused worldwide. In this research, the effects of different temperatures (15 °C, 22 °C, 30 °C, 32 °C, and 35 °C) and photoperiods (dark and light periods) on the continuous behavior responses of Zebrafish (Danio rerio) were investigated using an online monitoring system (OMS). We designed a new fish chamber with sensors to measure the behavior responses of zebrafish under different conditions. Data obtained from the OMS could be assessed for factors such as difference in swimming behavior, circadian rhythm, and avoidance behavior using latest software (MATLAB). The observed behavior anomalies on zebrafish under different temperatures and continuous photoperiods were statically significant (p < 0.05). We conclude that the new designed fish chamber (behavior sensors) is good in sensing behavioral responses of zebrafish under different conditions. The fish behavior strength could be a potential biomarker to assess the effects of environmental factors. The present study would be a basic platform for assessing the effects of different stressors simultaneously on swimming behavior of zebrafish.
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Affiliation(s)
- Yongyuan Hu
- Institute of Environment and Ecology, Shandong Normal University, 250358, Jinan, PR China
| | - Ruibin Zhao
- Institute of Environment and Ecology, Shandong Normal University, 250358, Jinan, PR China
| | - Rama-Krishnan Poopal
- Institute of Environment and Ecology, Shandong Normal University, 250358, Jinan, PR China
| | - Zongming Ren
- Institute of Environment and Ecology, Shandong Normal University, 250358, Jinan, PR China.
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9
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Peracchia C. Calmodulin-Cork Model of Gap Junction Channel Gating-One Molecule, Two Mechanisms. Int J Mol Sci 2020; 21:E4938. [PMID: 32668628 PMCID: PMC7404200 DOI: 10.3390/ijms21144938] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 07/08/2020] [Accepted: 07/10/2020] [Indexed: 12/11/2022] Open
Abstract
The Calmodulin-Cork gating model is based on evidence for the direct role of calmodulin (CaM) in channel gating. Indeed, chemical gating of cell-to-cell channels is sensitive to nanomolar cytosolic calcium concentrations [Ca2+]i. Calmodulin inhibitors and inhibition of CaM expression prevent chemical gating. CaMCC, a CaM mutant with higher Ca2+-sensitivity greatly increases chemical gating sensitivity (in CaMCC the NH2-terminal EF-hand pair (res. 9-76) is replaced by the COOH-terminal pair (res. 82-148). Calmodulin colocalizes with connexins. Connexins have high-affinity CaM binding sites. Several connexin mutants paired to wild-type connexins have a high gating sensitivity that is eliminated by inhibition of CaM expression. Repeated transjunctional voltage (Vj) pulses slowly and progressively close a large number of channels by the chemical/slow gate (CaM lobe). At the single-channel level, the chemical/slow gate closes and opens slowly with on-off fluctuations. The model proposes two types of CaM-driven gating: "Ca-CaM-Cork" and "CaM-Cork". In the first, gating involves Ca2+-induced CaM-activation. In the second, gating takes place without [Ca2+]i rise. The Ca-CaM-Cork gating is only reversed by a return of [Ca2+]i to resting values, while the CaM-Cork gating is reversed by Vj positive at the gated side.
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Affiliation(s)
- Camillo Peracchia
- Department of Pharmacology and Physiology, School of Medicine and Dentistry, University Rochester, Rochester, NY 14642, USA
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10
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Abstract
Of the 21 members of the connexin family, 4 (Cx37, Cx40, Cx43, and Cx45) are expressed in the endothelium and/or smooth muscle of intact blood vessels to a variable and dynamically regulated degree. Full-length connexins oligomerize and form channel structures connecting the cytosol of adjacent cells (gap junctions) or the cytosol with the extracellular space (hemichannels). The different connexins vary mainly with regard to length and sequence of their cytosolic COOH-terminal tails. These COOH-terminal parts, which in the case of Cx43 are also translated as independent short isoforms, are involved in various cellular signaling cascades and regulate cell functions. This review focuses on channel-dependent and -independent effects of connexins in vascular cells. Channels play an essential role in coordinating and synchronizing endothelial and smooth muscle activity and in their interplay, in the control of vasomotor actions of blood vessels including endothelial cell reactivity to agonist stimulation, nitric oxide-dependent dilation, and endothelial-derived hyperpolarizing factor-type responses. Further channel-dependent and -independent roles of connexins in blood vessel function range from basic processes of vascular remodeling and angiogenesis to vascular permeability and interactions with leukocytes with the vessel wall. Together, these connexin functions constitute an often underestimated basis for the enormous plasticity of vascular morphology and function enabling the required dynamic adaptation of the vascular system to varying tissue demands.
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Affiliation(s)
- Ulrich Pohl
- Walter-Brendel-Centre of Experimental Medicine, University Hospital, LMU Munich, Planegg-Martinsried, Germany; Biomedical Centre, Cardiovascular Physiology, LMU Munich, Planegg-Martinsried, Germany; German Centre for Cardiovascular Research, Partner Site Munich Heart Alliance, Munich, Germany; and Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
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11
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Ge Z, Liu J, Guo L, Yao G, Li Q, Wang L, Li J, Fan C. Programming Cell–Cell Communications with Engineered Cell Origami Clusters. J Am Chem Soc 2020; 142:8800-8808. [DOI: 10.1021/jacs.0c01580] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Zhilei Ge
- Frontiers Science Center for Transformative Molecules, School of Chemistry and Chemical Engineering, Institute of Molecular Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200024, China
| | - Jiangbo Liu
- Frontiers Science Center for Transformative Molecules, School of Chemistry and Chemical Engineering, Institute of Molecular Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200024, China
| | - Linjie Guo
- Bioimaging Center, Shanghai Synchrotron Radiation Facility, Zhangjiang Laboratory, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, China
- Division of Physical Biology, CAS Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
| | - Guangbao Yao
- Frontiers Science Center for Transformative Molecules, School of Chemistry and Chemical Engineering, Institute of Molecular Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200024, China
| | - Qian Li
- Frontiers Science Center for Transformative Molecules, School of Chemistry and Chemical Engineering, Institute of Molecular Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200024, China
| | - Lihua Wang
- Frontiers Science Center for Transformative Molecules, School of Chemistry and Chemical Engineering, Institute of Molecular Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200024, China
- Bioimaging Center, Shanghai Synchrotron Radiation Facility, Zhangjiang Laboratory, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, China
- Division of Physical Biology, CAS Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
| | - Jiang Li
- Bioimaging Center, Shanghai Synchrotron Radiation Facility, Zhangjiang Laboratory, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, China
- Division of Physical Biology, CAS Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
| | - Chunhai Fan
- Frontiers Science Center for Transformative Molecules, School of Chemistry and Chemical Engineering, Institute of Molecular Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200024, China
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12
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Peracchia C. Calmodulin-Mediated Regulation of Gap Junction Channels. Int J Mol Sci 2020; 21:E485. [PMID: 31940951 PMCID: PMC7014422 DOI: 10.3390/ijms21020485] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 01/03/2020] [Accepted: 01/06/2020] [Indexed: 12/25/2022] Open
Abstract
Evidence that neighboring cells uncouple from each other as one dies surfaced in the late 19th century, but it took almost a century for scientists to start understanding the uncoupling mechanism (chemical gating). The role of cytosolic free calcium (Ca2+i) in cell-cell channel gating was first reported in the mid-sixties. In these studies, only micromolar [Ca2+]i were believed to affect gating-concentrations reachable only in cell death, which would discard Ca2+i as a fine modulator of cell coupling. More recently, however, numerous researchers, including us, have reported the effectiveness of nanomolar [Ca2+]i. Since connexins do not have high-affinity calcium sites, the effectiveness of nanomolar [Ca2+]i suggests the role of Ca-modulated proteins, with calmodulin (CaM) being most obvious. Indeed, in 1981 we first reported that a CaM-inhibitor prevents chemical gating. Since then, the CaM role in gating has been confirmed by studies that tested it with a variety of approaches such as treatments with CaM-inhibitors, inhibition of CaM expression, expression of CaM mutants, immunofluorescent co-localization of CaM and gap junctions, and binding of CaM to peptides mimicking connexin domains identified as CaM targets. Our gating model envisions Ca2+-CaM to directly gate the channels by acting as a plug ("Cork" gating model), and probably also by affecting connexin conformation.
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Affiliation(s)
- Camillo Peracchia
- Department of Pharmacology and Physiology, School of Medicine and Dentistry, University of Rochester, Rochester, NY 14642, USA
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13
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Li Y, Liu W, Tang Q, Fan X, Hao Y, Gao L, Li Z, Cheng B, Chen X. Gap-Junction-Dependent Labeling of Nascent Proteins in Multicellular Networks. ACS Chem Biol 2019; 14:182-185. [PMID: 30715839 DOI: 10.1021/acschembio.8b01065] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Intercellular communication via gap junctions is crucial for orchestrating behaviors of multicellular systems. Imaging methods and electrophysiological techniques have been widely used to identify gap junctions and map the gap-junction-connected cell networks. However, analyzing gene expression within a gap-junction network remains challenging. Herein, we report the development of bio-orthogonal recording of translation in adjacent cells connected by gap junctions (BORTAC-GJ), a gap-junction-dependent protein tagging method based on local activation of clickable amino acid analogues that pass through gap junctions and are metabolically incorporated into nascent proteins. We demonstrated that BORTAC-GJ enabled selective labeling of nascent proteomes, thus recording translation, in cell networks connected by gap junctions, leaving unconnected cells not labeled. We further applied BORTAC-GJ to probe bystander STING activation triggered by gap-junction-mediated cGAMP transfer, an important process in innate immune response. BORTAC-GJ provides a means to investigate the gap-junction network at the proteome level and is broadly applicable for various cell types connected by gap junctions.
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Wu L, Dong A, Dong L, Wang SQ, Li Y. PARIS, an optogenetic method for functionally mapping gap junctions. eLife 2019; 8:43366. [PMID: 30638447 PMCID: PMC6396999 DOI: 10.7554/elife.43366] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Accepted: 01/12/2019] [Indexed: 12/29/2022] Open
Abstract
Cell-cell communication via gap junctions regulates a wide range of physiological processes by enabling the direct intercellular electrical and chemical coupling. However, the in vivo distribution and function of gap junctions remain poorly understood, partly due to the lack of non-invasive tools with both cell-type specificity and high spatiotemporal resolution. Here, we developed PARIS (pairing actuators and receivers to optically isolate gap junctions), a new fully genetically encoded tool for measuring the cell-specific gap junctional coupling (GJC). PARIS successfully enabled monitoring of GJC in several cultured cell lines under physiologically relevant conditions and in distinct genetically defined neurons in Drosophila brain, with ~10 s temporal resolution and sub-cellular spatial resolution. These results demonstrate that PARIS is a robust, highly sensitive tool for mapping functional gap junctions and study their regulation in both health and disease. For the tissues and organs of our bodies to work properly, the cells within them need to communicate with each other. One important part of cellular communication is the movement of signals – usually small molecules or ions – directly from one cell to another. This happens via structures called gap junctions, a type of sealed ‘channel’ that connects two cells. Gap junctions are found throughout the body, but investigating their precise roles in health and disease has been difficult. This is due to problems with the tools available to detect and monitor gap junctions. Some are simply harmful to cells, while others cannot be restricted to specific cell populations within a tissue. This lack of specificity makes it difficult to study gap junctions in the brain, where it is important to understand the connectivity patterns between distinct types of nerve cells. Wu et al. wanted to develop a new, non-harmful method to track gap junctions in distinct groups of cells within living tissues. To do this, Wu et al. devised PARIS, a two-part, genetically encoded system. The first part comprises a light-sensitive molecular ‘pump’, which can only be turned on by shining a laser onto the cell of interest. When the pump is active, it transports hydrogen ions out of the cell. The second part of the system is a fluorescent sensor, present inside ‘receiving’ cells, which responds to the outcoming hydrogen ions (small enough to pass through gap junctions). If an illuminated ‘signaling’ cell is connected via gap junctions to cells containing the fluorescent sensor, they will light up within seconds, but other cells not connected through gap junctions will not. The researchers first tested PARIS in cultured human and rat cells that had been genetically engineered to produce both components of the system. The experiments confirmed that PARIS could both detect networks of gap junctions in healthy cells and reveal when these networks had been disrupted, for instance by drugs or genetic mutations. Experiments using fruit flies demonstrated that PARIS was stable in living tissue and could also map the gap junctions connecting specific groups of nerve cells. PARIS is a valuable addition to the toolbox available to study cell communication. In the future, it could help increase our understanding of diseases characterized by defective gap junctions, such as seizures, cardiac irregularities, and even some cancers.
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Affiliation(s)
- Ling Wu
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China.,PKU-IDG/McGovern Institute for Brain Research, Beijing, China.,Peking-Tsinghua Center for Life Sciences, Beijing, China
| | - Ao Dong
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China.,PKU-IDG/McGovern Institute for Brain Research, Beijing, China.,Peking-Tsinghua Center for Life Sciences, Beijing, China
| | - Liting Dong
- Peking-Tsinghua Center for Life Sciences, Beijing, China
| | - Shi-Qiang Wang
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China
| | - Yulong Li
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China.,PKU-IDG/McGovern Institute for Brain Research, Beijing, China.,Peking-Tsinghua Center for Life Sciences, Beijing, China.,Chinese Institute for Brain Research, Beijing, China
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15
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Dong A, Liu S, Li Y. Gap Junctions in the Nervous System: Probing Functional Connections Using New Imaging Approaches. Front Cell Neurosci 2018; 12:320. [PMID: 30283305 PMCID: PMC6156252 DOI: 10.3389/fncel.2018.00320] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Accepted: 09/03/2018] [Indexed: 11/13/2022] Open
Abstract
Gap junctions are channels that physically connect adjacent cells, mediating the rapid exchange of small molecules, and playing an essential role in a wide range of physiological processes in nearly every system in the body, including the nervous system. Thus, altered function of gap junctions has been linked with a plethora of diseases and pathological conditions. Being able to measure and characterize the distribution, function, and regulation of gap junctions in intact tissue is therefore essential for understanding the physiological and pathophysiological roles that gap junctions play. In recent decades, several robust in vitro and in vivo methods have been developed for detecting and characterizing gap junctions. Here, we review the currently available methods with respect to invasiveness, signal-to-noise ratio, temporal resolution and others, highlighting the recently developed chemical tracers and hybrid imaging systems that use novel chemical compounds and/or genetically encoded enzymes, transporters, channels, and fluorescent proteins in order to map gap junctions. Finally, we discuss possible avenues for further improving existing techniques in order to achieve highly sensitive, cell type-specific, non-invasive measures of in vivo gap junction function with high throughput and high spatiotemporal resolution.
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Affiliation(s)
- Ao Dong
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China.,PKU-IDG/McGovern Institute for Brain Research, Beijing, China.,Peking-Tsinghua Center for Life Sciences, Beijing, China
| | - Simin Liu
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China.,PKU-IDG/McGovern Institute for Brain Research, Beijing, China
| | - Yulong Li
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China.,PKU-IDG/McGovern Institute for Brain Research, Beijing, China.,Peking-Tsinghua Center for Life Sciences, Beijing, China
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16
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Zheng Y, Zheng X, Xiang Y, Tong A. Photoactivatable aggregation-induced emission of triphenylmethanol. Chem Commun (Camb) 2017; 53:11130-11133. [PMID: 28800140 DOI: 10.1039/c7cc04693f] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Triphenylmethanol (TPOH) is a non-fluorescent compound. Interestingly, after UV irradiation at 254 nm, TPOH showed a strong blue fluorescence on a solid surface. Moreover, the fluorescence can be quenched by UV irradiation at 365 nm, making the photoactivatable fluorescence reversible. TPOH is thus applied for rewritable photopatterning tuned by UV light.
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Affiliation(s)
- Yue Zheng
- Department of Chemistry, Beijing Key Laboratory for Analytical Methods and Instrumentation, Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Tsinghua University, Beijing 100084, P. R. China.
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17
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Leybaert L, Lampe PD, Dhein S, Kwak BR, Ferdinandy P, Beyer EC, Laird DW, Naus CC, Green CR, Schulz R. Connexins in Cardiovascular and Neurovascular Health and Disease: Pharmacological Implications. Pharmacol Rev 2017; 69:396-478. [PMID: 28931622 PMCID: PMC5612248 DOI: 10.1124/pr.115.012062] [Citation(s) in RCA: 164] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Connexins are ubiquitous channel forming proteins that assemble as plasma membrane hemichannels and as intercellular gap junction channels that directly connect cells. In the heart, gap junction channels electrically connect myocytes and specialized conductive tissues to coordinate the atrial and ventricular contraction/relaxation cycles and pump function. In blood vessels, these channels facilitate long-distance endothelial cell communication, synchronize smooth muscle cell contraction, and support endothelial-smooth muscle cell communication. In the central nervous system they form cellular syncytia and coordinate neural function. Gap junction channels are normally open and hemichannels are normally closed, but pathologic conditions may restrict gap junction communication and promote hemichannel opening, thereby disturbing a delicate cellular communication balance. Until recently, most connexin-targeting agents exhibited little specificity and several off-target effects. Recent work with peptide-based approaches has demonstrated improved specificity and opened avenues for a more rational approach toward independently modulating the function of gap junctions and hemichannels. We here review the role of connexins and their channels in cardiovascular and neurovascular health and disease, focusing on crucial regulatory aspects and identification of potential targets to modify their function. We conclude that peptide-based investigations have raised several new opportunities for interfering with connexins and their channels that may soon allow preservation of gap junction communication, inhibition of hemichannel opening, and mitigation of inflammatory signaling.
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Affiliation(s)
- Luc Leybaert
- Physiology Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium (L.L.); Translational Research Program, Fred Hutchinson Cancer Research Center, Seattle, Washington (P.D.L.); Institute for Pharmacology, University of Leipzig, Leipzig, Germany (S.D.); Department of Pathology and Immunology, Department of Medical Specialization-Cardiology, University of Geneva, Geneva, Switzerland (B.R.K.); Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary (P.F.); Pharmahungary Group, Szeged, Hungary (P.F.); Department of Pediatrics, University of Chicago, Chicago, Illinois (E.C.B.); Department of Anatomy and Cell Biology, University of Western Ontario, Dental Science Building, London, Ontario, Canada (D.W.L.); Cellular and Physiological Sciences, Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada (C.C.N.); Department of Ophthalmology and The New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (C.R.G.); and Physiologisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany (R.S.)
| | - Paul D Lampe
- Physiology Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium (L.L.); Translational Research Program, Fred Hutchinson Cancer Research Center, Seattle, Washington (P.D.L.); Institute for Pharmacology, University of Leipzig, Leipzig, Germany (S.D.); Department of Pathology and Immunology, Department of Medical Specialization-Cardiology, University of Geneva, Geneva, Switzerland (B.R.K.); Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary (P.F.); Pharmahungary Group, Szeged, Hungary (P.F.); Department of Pediatrics, University of Chicago, Chicago, Illinois (E.C.B.); Department of Anatomy and Cell Biology, University of Western Ontario, Dental Science Building, London, Ontario, Canada (D.W.L.); Cellular and Physiological Sciences, Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada (C.C.N.); Department of Ophthalmology and The New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (C.R.G.); and Physiologisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany (R.S.)
| | - Stefan Dhein
- Physiology Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium (L.L.); Translational Research Program, Fred Hutchinson Cancer Research Center, Seattle, Washington (P.D.L.); Institute for Pharmacology, University of Leipzig, Leipzig, Germany (S.D.); Department of Pathology and Immunology, Department of Medical Specialization-Cardiology, University of Geneva, Geneva, Switzerland (B.R.K.); Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary (P.F.); Pharmahungary Group, Szeged, Hungary (P.F.); Department of Pediatrics, University of Chicago, Chicago, Illinois (E.C.B.); Department of Anatomy and Cell Biology, University of Western Ontario, Dental Science Building, London, Ontario, Canada (D.W.L.); Cellular and Physiological Sciences, Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada (C.C.N.); Department of Ophthalmology and The New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (C.R.G.); and Physiologisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany (R.S.)
| | - Brenda R Kwak
- Physiology Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium (L.L.); Translational Research Program, Fred Hutchinson Cancer Research Center, Seattle, Washington (P.D.L.); Institute for Pharmacology, University of Leipzig, Leipzig, Germany (S.D.); Department of Pathology and Immunology, Department of Medical Specialization-Cardiology, University of Geneva, Geneva, Switzerland (B.R.K.); Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary (P.F.); Pharmahungary Group, Szeged, Hungary (P.F.); Department of Pediatrics, University of Chicago, Chicago, Illinois (E.C.B.); Department of Anatomy and Cell Biology, University of Western Ontario, Dental Science Building, London, Ontario, Canada (D.W.L.); Cellular and Physiological Sciences, Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada (C.C.N.); Department of Ophthalmology and The New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (C.R.G.); and Physiologisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany (R.S.)
| | - Peter Ferdinandy
- Physiology Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium (L.L.); Translational Research Program, Fred Hutchinson Cancer Research Center, Seattle, Washington (P.D.L.); Institute for Pharmacology, University of Leipzig, Leipzig, Germany (S.D.); Department of Pathology and Immunology, Department of Medical Specialization-Cardiology, University of Geneva, Geneva, Switzerland (B.R.K.); Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary (P.F.); Pharmahungary Group, Szeged, Hungary (P.F.); Department of Pediatrics, University of Chicago, Chicago, Illinois (E.C.B.); Department of Anatomy and Cell Biology, University of Western Ontario, Dental Science Building, London, Ontario, Canada (D.W.L.); Cellular and Physiological Sciences, Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada (C.C.N.); Department of Ophthalmology and The New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (C.R.G.); and Physiologisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany (R.S.)
| | - Eric C Beyer
- Physiology Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium (L.L.); Translational Research Program, Fred Hutchinson Cancer Research Center, Seattle, Washington (P.D.L.); Institute for Pharmacology, University of Leipzig, Leipzig, Germany (S.D.); Department of Pathology and Immunology, Department of Medical Specialization-Cardiology, University of Geneva, Geneva, Switzerland (B.R.K.); Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary (P.F.); Pharmahungary Group, Szeged, Hungary (P.F.); Department of Pediatrics, University of Chicago, Chicago, Illinois (E.C.B.); Department of Anatomy and Cell Biology, University of Western Ontario, Dental Science Building, London, Ontario, Canada (D.W.L.); Cellular and Physiological Sciences, Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada (C.C.N.); Department of Ophthalmology and The New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (C.R.G.); and Physiologisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany (R.S.)
| | - Dale W Laird
- Physiology Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium (L.L.); Translational Research Program, Fred Hutchinson Cancer Research Center, Seattle, Washington (P.D.L.); Institute for Pharmacology, University of Leipzig, Leipzig, Germany (S.D.); Department of Pathology and Immunology, Department of Medical Specialization-Cardiology, University of Geneva, Geneva, Switzerland (B.R.K.); Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary (P.F.); Pharmahungary Group, Szeged, Hungary (P.F.); Department of Pediatrics, University of Chicago, Chicago, Illinois (E.C.B.); Department of Anatomy and Cell Biology, University of Western Ontario, Dental Science Building, London, Ontario, Canada (D.W.L.); Cellular and Physiological Sciences, Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada (C.C.N.); Department of Ophthalmology and The New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (C.R.G.); and Physiologisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany (R.S.)
| | - Christian C Naus
- Physiology Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium (L.L.); Translational Research Program, Fred Hutchinson Cancer Research Center, Seattle, Washington (P.D.L.); Institute for Pharmacology, University of Leipzig, Leipzig, Germany (S.D.); Department of Pathology and Immunology, Department of Medical Specialization-Cardiology, University of Geneva, Geneva, Switzerland (B.R.K.); Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary (P.F.); Pharmahungary Group, Szeged, Hungary (P.F.); Department of Pediatrics, University of Chicago, Chicago, Illinois (E.C.B.); Department of Anatomy and Cell Biology, University of Western Ontario, Dental Science Building, London, Ontario, Canada (D.W.L.); Cellular and Physiological Sciences, Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada (C.C.N.); Department of Ophthalmology and The New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (C.R.G.); and Physiologisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany (R.S.)
| | - Colin R Green
- Physiology Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium (L.L.); Translational Research Program, Fred Hutchinson Cancer Research Center, Seattle, Washington (P.D.L.); Institute for Pharmacology, University of Leipzig, Leipzig, Germany (S.D.); Department of Pathology and Immunology, Department of Medical Specialization-Cardiology, University of Geneva, Geneva, Switzerland (B.R.K.); Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary (P.F.); Pharmahungary Group, Szeged, Hungary (P.F.); Department of Pediatrics, University of Chicago, Chicago, Illinois (E.C.B.); Department of Anatomy and Cell Biology, University of Western Ontario, Dental Science Building, London, Ontario, Canada (D.W.L.); Cellular and Physiological Sciences, Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada (C.C.N.); Department of Ophthalmology and The New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (C.R.G.); and Physiologisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany (R.S.)
| | - Rainer Schulz
- Physiology Group, Department of Basic Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium (L.L.); Translational Research Program, Fred Hutchinson Cancer Research Center, Seattle, Washington (P.D.L.); Institute for Pharmacology, University of Leipzig, Leipzig, Germany (S.D.); Department of Pathology and Immunology, Department of Medical Specialization-Cardiology, University of Geneva, Geneva, Switzerland (B.R.K.); Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary (P.F.); Pharmahungary Group, Szeged, Hungary (P.F.); Department of Pediatrics, University of Chicago, Chicago, Illinois (E.C.B.); Department of Anatomy and Cell Biology, University of Western Ontario, Dental Science Building, London, Ontario, Canada (D.W.L.); Cellular and Physiological Sciences, Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada (C.C.N.); Department of Ophthalmology and The New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (C.R.G.); and Physiologisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany (R.S.)
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18
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Mathews J, Levin M. Gap junctional signaling in pattern regulation: Physiological network connectivity instructs growth and form. Dev Neurobiol 2017; 77:643-673. [PMID: 27265625 PMCID: PMC10478170 DOI: 10.1002/dneu.22405] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 05/27/2016] [Accepted: 05/31/2016] [Indexed: 12/19/2022]
Abstract
Gap junctions (GJs) are aqueous channels that allow cells to communicate via physiological signals directly. The role of gap junctional connectivity in determining single-cell functions has long been recognized. However, GJs have another important role: the regulation of large-scale anatomical pattern. GJs are not only versatile computational elements that allow cells to control which small molecule signals they receive and emit, but also establish connectivity patterns within large groups of cells. By dynamically regulating the topology of bioelectric networks in vivo, GJs underlie the ability of many tissues to implement complex morphogenesis. Here, a review of recent data on patterning roles of GJs in growth of the zebrafish fin, the establishment of left-right patterning, the developmental dysregulation known as cancer, and the control of large-scale head-tail polarity, and head shape in planarian regeneration has been reported. A perspective in which GJs are not only molecular features functioning in single cells, but also enable global neural-like dynamics in non-neural somatic tissues has been proposed. This view suggests a rich program of future work which capitalizes on the rapid advances in the biophysics of GJs to exploit GJ-mediated global dynamics for applications in birth defects, regenerative medicine, and morphogenetic bioengineering. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 643-673, 2017.
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Affiliation(s)
- Juanita Mathews
- Department of Biology, Tufts Center for Regenerative and Developmental Biology, Tufts University, Medford, MA
| | - Michael Levin
- Department of Biology, Tufts Center for Regenerative and Developmental Biology, Tufts University, Medford, MA
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19
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Klötzner DP, Klehs K, Heilemann M, Heckel A. A new photoactivatable near-infrared-emitting QCy7 fluorophore for single-molecule super-resolution microscopy. Chem Commun (Camb) 2017; 53:9874-9877. [DOI: 10.1039/c7cc04996j] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In this work we present a new photoactivatable QCy7-based fluorophore and demonstrate its application in single-molecule super-resolution microscopy.
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Affiliation(s)
- Dean-Paulos Klötzner
- Goethe University Frankfurt
- Institute of Organic Chemistry and Chemical Biology
- 60438 Frankfurt
- Germany
| | - Kathrin Klehs
- Goethe University Frankfurt
- Institute of Physical and Theoretical Chemistry
- 60438 Frankfurt
- Germany
| | - Mike Heilemann
- Goethe University Frankfurt
- Institute of Physical and Theoretical Chemistry
- 60438 Frankfurt
- Germany
| | - Alexander Heckel
- Goethe University Frankfurt
- Institute of Organic Chemistry and Chemical Biology
- 60438 Frankfurt
- Germany
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20
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Ren Z, Li S, Zhang T, Qi L, Xing N, Yu H, Jian J, Chon TS, Tang B. Behavior persistence in defining threshold switch in stepwise response of aquatic organisms exposed to toxic chemicals. CHEMOSPHERE 2016; 165:409-417. [PMID: 27668718 DOI: 10.1016/j.chemosphere.2016.09.065] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2016] [Revised: 09/13/2016] [Accepted: 09/15/2016] [Indexed: 06/06/2023]
Abstract
As a characteristic in bacterial colony, persistence model described the dynamics of two subpopulations (normal (n) and persister (p)). In order to illustrate the switch of "Threshold" in the stepwise behavior responses of organisms, it is hypothesized that total behavior (Bt) of organisms consists of two types in behavior tendency, intoxication (Bp) and normal/recovery behavior (Bn). Both Bp and Bn could be concurrently affected by environmental stress E, and behavior response modes (M) are decided by the relationship between E and toxicity threshold of test organisms (Ti). The results suggested stress constant λ was decided by the constant rates gnE,gpE, an and ap. Due to different stress constant λ, the behavior responses of indicators showed great difference in different M, which included 'safe mode' (Ms), 'acclimation mode' (Mac), 'adjustment mode' (Maj) and 'toxic effect' (Mte). Usually, Bt during Ms could maintain around 0.8, and Mte would happen once it is lower than 0.2. According to the relationship between Bt values and E changes in 7 Majs, behavior persistence relying on adjustment could reflect the behavior homeostasis of organisms under environmental stress and be regarded as a threshold switch for the stepwise behavior responses. The mathematical analysis of behavior persistence allows making a quantitative prediction on environment assessment that would promote the emergence of persistence, as well as evaluating its ecological implications.
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Affiliation(s)
- Zongming Ren
- Institute of Environment and Ecology, Shandong Normal University, Ji'nan 250014, PR China.
| | - Shangge Li
- Institute of Environment and Ecology, Shandong Normal University, Ji'nan 250014, PR China
| | - Tingting Zhang
- Institute of Environment and Ecology, Shandong Normal University, Ji'nan 250014, PR China
| | - Luhuizi Qi
- Institute of Environment and Ecology, Shandong Normal University, Ji'nan 250014, PR China
| | - Na Xing
- Institute of Environment and Ecology, Shandong Normal University, Ji'nan 250014, PR China
| | - Huimin Yu
- Institute of Environment and Ecology, Shandong Normal University, Ji'nan 250014, PR China
| | - Jinfeng Jian
- Institute of Environment and Ecology, Shandong Normal University, Ji'nan 250014, PR China
| | - Tae-Soo Chon
- Department of Biological Sciences, Pusan National University, Busan 609735, Republic of Korea; Ecology and Future Research Association, Busan 609802, Republic of Korea
| | - Bo Tang
- Institute of Environment and Ecology, Shandong Normal University, Ji'nan 250014, PR China.
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21
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Xiao H, Chen Y, Yuan E, Li W, Jiang Z, Wei L, Su H, Zeng W, Gan Y, Wang Z, Yuan B, Qin S, Leng X, Zhou X, Liu S, Zhou X. Obtaining More Accurate Signals: Spatiotemporal Imaging of Cancer Sites Enabled by a Photoactivatable Aptamer-Based Strategy. ACS APPLIED MATERIALS & INTERFACES 2016; 8:23542-23548. [PMID: 27550088 DOI: 10.1021/acsami.6b07450] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Early cancer diagnosis is of great significance to relative cancer prevention and clinical therapy, and it is crucial to efficiently recognize cancerous tumor sites at the molecular level. Herein, we proposed a versatile and efficient strategy based on aptamer recognition and photoactivation imaging for cancer diagnosis. This is the first time that a visible light-controlled photoactivatable aptamer-based platform has been applied for cancer diagnosis. The photoactivatable aptamer-based strategy can accurately detect nucleolin-overexpressed tumor cells and can be used for highly selective cancer cell screening and tissue imaging. This strategy is available for both formalin-fixed paraffin-embedded tissue specimens and frozen sections. Moreover, the photoactivation techniques showed great progress in more accurate and persistent imaging to the use of traditional fluorophores. Significantly, the application of this strategy can produce the same accurate results in tissue specimen analysis as with classical hematoxylin-eosin staining and immunohistochemical technology.
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Affiliation(s)
- Heng Xiao
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology , Wuhan 430022, P.R. China
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22
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Tracking Dynamic Gap Junctional Coupling in Live Cells by Local Photoactivation and Fluorescence Imaging. Methods Mol Biol 2016. [PMID: 27207295 DOI: 10.1007/978-1-4939-3664-9_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Intercellular communication through gap junction channels is crucial for maintaining cell homeostasis and synchronizing physiological functions of tissues and organs. In this chapter, we present a noninvasive fluorescence imaging assay termed LAMP (local activation of a molecular fluorescent probe) that consists of the following steps: loading cells with a caged and cell permeable coumarin probe (NPE-HCCC2/AM), locally photolyzing the caged coumarin in one or a subpopulation of coupled cells, monitoring cell-cell dye transfer by digital fluorescence microscopy, and post-acquisition analysis to quantify the rate of junction dye transfer using Fick's equation. The LAMP assay can be conveniently carried out in fully intact cells to assess the extent and degree of cell coupling, and is compatible with other fluorophores emitting at different wavelengths to allow multicolor imaging. Moreover, by carrying out multiple photo-activations in a coupled cell pair, LAMP assay can track changes in cell coupling strength between coupled cells, hence providing a powerful method for investigating the regulation of junctional coupling by cellular biochemical changes.
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23
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Calcium Wave Propagation Triggered by Local Mechanical Stimulation as a Method for Studying Gap Junctions and Hemichannels. Methods Mol Biol 2016; 1437:203-11. [PMID: 27207297 DOI: 10.1007/978-1-4939-3664-9_15] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Intercellular communication is essential for the coordination and synchronization of cellular processes. Gap junction channels play an important role to communicate between cells and organs, including the brain, lung, liver, lens, retina, and heart. Gap junctions enable a direct route for ions like calcium and potassium, and low molecular weight compounds, such as inositol 1,4,5-trisphosphate, cyclic adenosine monophosphate, and various kinds of metabolites to pass between cells. Intercellular calcium wave propagation evoked by a local mechanical stimulus is one of the gap junction assays to study intercellular communication. In experimental settings, an intercellular calcium wave can be elicited by applying a mechanical stimulus to a single cell. Here, we describe the use of monolayers of primary bovine corneal endothelial cells as a model to study intercellular communication. Calcium wave propagation was assayed by imaging fluorescent calcium in bovine corneal endothelial cells loaded with a fluorescent calcium dye using a confocal microscope. Spatial changes in intercellular calcium concentration following mechanical stimulation were measured in the mechanical stimulated cell and in the neighboring cells. The active area (i.e., total surface area of responsive cells) of a calcium wave can be measured and used for studying the function and regulation of gap junction channels as well as hemichannels in a variety of cell systems.
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Abstract
The scrape loading/dye transfer (SL/DT) technique is a simple functional assay for the simultaneous assessment of gap junctional intercellular communication (GJIC) in a large population of cells. The equipment needs are minimal and are typically met in standard cell biology labs, and SL/DT is the simplest and quickest of all the assays that measure GJIC. This assay has also been adapted for in vivo studies. The SL/DT assay is also conducive to a high-throughput setup with automated fluorescence microscopy imaging and analysis to elucidate more samples in shorter time, and hence can serve a broad range of in vitro pharmacological and toxicological needs.
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Affiliation(s)
- Pavel Babica
- RECETOX-Research Centre for Toxic Compounds in the Environment, Masaryk University, Kamenice 753/5, Brno, 62500, Czech Republic.
| | - Iva Sovadinová
- RECETOX-Research Centre for Toxic Compounds in the Environment, Masaryk University, Kamenice 753/5, Brno, 62500, Czech Republic
| | - Brad L Upham
- Department of Pediatrics and Human Development, and the Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, USA
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Maes M, Yanguas SC, Willebrords J, Vinken M. Models and methods for in vitro testing of hepatic gap junctional communication. Toxicol In Vitro 2015; 30:569-577. [PMID: 26420514 PMCID: PMC4685743 DOI: 10.1016/j.tiv.2015.09.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 08/11/2015] [Accepted: 09/24/2015] [Indexed: 12/17/2022]
Abstract
Inherent to their pivotal roles in controlling all aspects of the liver cell life cycle, hepatocellular gap junctions are frequently disrupted upon impairment of the homeostatic balance, as occurs during liver toxicity. Hepatic gap junctions, which are mainly built up by connexin32, are specifically targeted by tumor promoters and epigenetic carcinogens. This renders inhibition of gap junction functionality a suitable indicator for the in vitro detection of nongenotoxic hepatocarcinogenicity. The establishment of a reliable liver gap junction inhibition assay for routine in vitro testing purposes requires a cellular system in which gap junctions are expressed at an in vivo-like level as well as an appropriate technique to probe gap junction activity. Both these models and methods are discussed in the current paper, thereby focusing on connexin32-based gap junctions.
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Affiliation(s)
- Michaël Maes
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium
| | - Sara Crespo Yanguas
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium
| | - Joost Willebrords
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium
| | - Mathieu Vinken
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium
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Christodoulou N, Skourides P. Cell-Autonomous Ca 2+ Flashes Elicit Pulsed Contractions of an Apical Actin Network to Drive Apical Constriction during Neural Tube Closure. Cell Rep 2015; 13:2189-202. [DOI: 10.1016/j.celrep.2015.11.017] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Revised: 09/13/2015] [Accepted: 11/03/2015] [Indexed: 01/08/2023] Open
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Sumi T, Kaburagi T, Morimoto M, Une K, Sotome H, Ito S, Miyasaka H, Irie M. Fluorescent Photochromic Diarylethene That Turns on with Visible Light. Org Lett 2015; 17:4802-5. [DOI: 10.1021/acs.orglett.5b02361] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Takaki Sumi
- Department
of Chemistry and Research Center for Smart Molecules, Rikkyo University, Nishi-Ikebukuro
3-34-1, Toshima-ku, Tokyo 171-8501, Japan
| | - Tomohiro Kaburagi
- Department
of Chemistry and Research Center for Smart Molecules, Rikkyo University, Nishi-Ikebukuro
3-34-1, Toshima-ku, Tokyo 171-8501, Japan
| | - Masakazu Morimoto
- Department
of Chemistry and Research Center for Smart Molecules, Rikkyo University, Nishi-Ikebukuro
3-34-1, Toshima-ku, Tokyo 171-8501, Japan
| | - Kanako Une
- Division
of Frontier Materials Science and Center for Advanced Interdisciplinary
Research, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Hikaru Sotome
- Division
of Frontier Materials Science and Center for Advanced Interdisciplinary
Research, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Syoji Ito
- Division
of Frontier Materials Science and Center for Advanced Interdisciplinary
Research, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Hiroshi Miyasaka
- Division
of Frontier Materials Science and Center for Advanced Interdisciplinary
Research, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Masahiro Irie
- Department
of Chemistry and Research Center for Smart Molecules, Rikkyo University, Nishi-Ikebukuro
3-34-1, Toshima-ku, Tokyo 171-8501, Japan
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Li D, Liu L, Li WH. Genetic targeting of a small fluorescent zinc indicator to cell surface for monitoring zinc secretion. ACS Chem Biol 2015; 10:1054-63. [PMID: 25572404 DOI: 10.1021/cb5007536] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Numerous mammalian cells contain Zn2+ in their secretory granules. During secretion, Zn2+ is coreleased with granular cargos into extracellular medium so Zn2+ serves as a convenient surrogate marker for tracking the dynamics of secretion. Fluorescent Zn2+ sensors that can be selectively targeted to cells of interest would be invaluable tools for imaging Zn2+ release in multicellular systems including tissues and live animals. Exploiting the HaloTag labeling technology and using an optimized linker, we have engineered a fluorescent Zn2+ indicator that displayed a 15-fold fluorescence enhancement upon Zn2+ binding while reacting efficiently with a HaloTag enzyme in a cellular environment. Two-color imaging of ZIMIR-HaloTag and a red-emitting calcium indicator in pancreatic islet beta cells demonstrated that photoactivation of a channelrhodopsin was able to induce exocytosis of Zn2+/insulin granules and revealed heterogeneity in secretory activity along the cell membrane that was uncoupled from cellular Ca2+ activity. This integrated photonic approach for imaging and controlling the release of large dense core granules provides exquisite cellular selectivity and should facilitate future studies of stimulus-secretion coupling and paracrine signaling in secretory cells.
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Affiliation(s)
- Daliang Li
- Departments of Cell Biology
and Biochemistry, University of Texas Southwestern Medical Center, 6000
Harry Hines Boulevard, Dallas, Texas 75390-9039, United States
| | - Lin Liu
- Departments of Cell Biology
and Biochemistry, University of Texas Southwestern Medical Center, 6000
Harry Hines Boulevard, Dallas, Texas 75390-9039, United States
| | - Wen-Hong Li
- Departments of Cell Biology
and Biochemistry, University of Texas Southwestern Medical Center, 6000
Harry Hines Boulevard, Dallas, Texas 75390-9039, United States
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Bao C, Zhu L, Lin Q, Tian H. Building biomedical materials using photochemical bond cleavage. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2015; 27:1647-62. [PMID: 25655424 DOI: 10.1002/adma.201403783] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Revised: 12/02/2014] [Indexed: 05/06/2023]
Abstract
Light can be used as an external trigger to precisely determine where and when a process is initiated as well as how much of the process is being consumed. Phototriggers are a type of photoresponsive functional group that undergo an irreversible photolysis reaction by selectively breaking a chemical bond, enabling three fundamental functions: the photoactivation of fluorescent and bioactive molecules; the photocleavable degradation of macromolecular materials; and the photorelease of drugs, active groups, or surface charges from carriers and interfaces. With the expanded applications of light-controlled technology, particularly in living systems, new challenges and improvements of phototriggers are required to fulfill the demands for better sensitivity, faster kinetics, and more-demanding biomedical applications. Here, improvements to several conventional phototriggers are highlighted, and their notable, representative biomedical applications and their challenges are discussed.
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Affiliation(s)
- Chunyan Bao
- Key Laboratory for Advanced Materials, Institute of Fine Chemicals, East China University of Science and Technology, 130# Meilong Road, Shanghai, 200237, China
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Abstract
The interactions between pairs of cells and within multicellular assemblies are critical to many biological processes such as intercellular communication, tissue and organ formation, immunological reactions, and cancer metastasis. The ability to precisely control the position of cells relative to one another and within larger cellular assemblies will enable the investigation and characterization of phenomena not currently accessible by conventional in vitro methods. We present a versatile surface acoustic wave technique that is capable of controlling the intercellular distance and spatial arrangement of cells with micrometer level resolution. This technique is, to our knowledge, among the first of its kind to marry high precision and high throughput into a single extremely versatile and wholly biocompatible technology. We demonstrated the capabilities of the system to precisely control intercellular distance, assemble cells with defined geometries, maintain cellular assemblies in suspension, and translate these suspended assemblies to adherent states, all in a contactless, biocompatible manner. As an example of the power of this system, this technology was used to quantitatively investigate the gap junctional intercellular communication in several homotypic and heterotypic populations by visualizing the transfer of fluorescent dye between cells.
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Farnsworth NL, Hemmati A, Pozzoli M, Benninger RKP. Fluorescence recovery after photobleaching reveals regulation and distribution of connexin36 gap junction coupling within mouse islets of Langerhans. J Physiol 2014; 592:4431-46. [PMID: 25172942 PMCID: PMC4287745 DOI: 10.1113/jphysiol.2014.276733] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Accepted: 08/11/2014] [Indexed: 11/08/2022] Open
Abstract
The pancreatic islets are central to the maintenance of glucose homeostasis through insulin secretion. Glucose‐stimulated insulin secretion is tightly linked to electrical activity in β cells within the islet. Gap junctions, composed of connexin36 (Cx36), form intercellular channels between β cells, synchronizing electrical activity and insulin secretion. Loss of gap junction coupling leads to altered insulin secretion dynamics and disrupted glucose homeostasis. Gap junction coupling is known to be disrupted in mouse models of pre‐diabetes. Although approaches to measure gap junction coupling have been devised, they either lack cell specificity, suitable quantification of coupling or spatial resolution, or are invasive. The purpose of this study was to develop fluorescence recovery after photobleaching (FRAP) as a technique to accurately and robustly measure gap junction coupling in the islet. The cationic dye Rhodamine 123 was used with FRAP to quantify dye diffusion between islet β cells as a measure of Cx36 gap junction coupling. Measurements in islets with reduced Cx36 verified the accuracy of this technique in distinguishing between distinct levels of gap junction coupling. Analysis of individual cells revealed that the distribution of coupling across the islet is highly heterogeneous. Analysis of several modulators of gap junction coupling revealed glucose‐ and cAMP‐dependent modulation of gap junction coupling in islets. Finally, FRAP was used to determine cell population specific coupling, where no functional gap junction coupling was observed between α cells and β cells in the islet. The results of this study show FRAP to be a robust technique which provides the cellular resolution to quantify the distribution and regulation of Cx36 gap junction coupling in specific cell populations within the islet. Future studies utilizing this technique may elucidate the role of gap junction coupling in the progression of diabetes and identify mechanisms of gap junction regulation for potential therapies.
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Affiliation(s)
- Nikki L Farnsworth
- Barbara Davis Center for Childhood Diabetes, University of Colorado, Aurora, CO, USA
| | - Alireza Hemmati
- Department of Bioengineering, University of Colorado, Aurora, CO, USA
| | - Marina Pozzoli
- Department of Bioengineering, University of Colorado, Aurora, CO, USA
| | - Richard K P Benninger
- Barbara Davis Center for Childhood Diabetes, University of Colorado, Aurora, CO, USA Department of Bioengineering, University of Colorado, Aurora, CO, USA
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Nekongo EE, Popik VV. Photoactivatable fluorescein derivatives caged with a (3-hydroxy-2-naphthalenyl)methyl group. J Org Chem 2014; 79:7665-71. [PMID: 25036698 DOI: 10.1021/jo501116g] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The (3-hydroxy-2-naphthalenyl)methyl (NQMP) group represents an efficient photocage for fluorescein-based dyes. Thus, irradiation of the 6-NQMP ether of 2'-hydroxymethylfluorescein with low-intensity UVA light results in a 4-fold increase in emission intensity. Photoactivation of nonfluorescent NQMP-caged 3-allyloxyfluorescein produces a highly emissive fluorescein monoether. To facilitate conjugation of the caged dye to the substrate of interest via click chemistry, the allyloxy appendage was functionalized with an azide moiety.
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Affiliation(s)
- Emmanuel E Nekongo
- Department of Chemistry, University of Georgia , Athens, Georgia 30602, United States
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Abstract
A unique live-cell printing technique, termed "Block-Cell-Printing" (BloC-Printing), allows for convenient, precise, multiplexed, and high-throughput printing of functional single-cell arrays. Adapted from woodblock printing techniques, the approach employs microfluidic arrays of hook-shaped traps to hold cells at designated positions and directly transfer the anchored cells onto various substrates. BloC-Printing has a minimum turnaround time of 0.5 h, a maximum resolution of 5 µm, close to 100% cell viability, the ability to handle multiple cell types, and efficiently construct protrusion-connected single-cell arrays. The approach enables the large-scale formation of heterotypic cell pairs with controlled morphology and allows for material transport through gap junction intercellular communication. When six types of breast cancer cells are allowed to extend membrane protrusions in the BloC-Printing device for 3 h, multiple biophysical characteristics of cells--including the protrusion percentage, extension rate, and cell length--are easily quantified and found to correlate well with their migration levels. In light of this discovery, BloC-Printing may serve as a rapid and high-throughput cell protrusion characterization tool to measure the invasion and migration capability of cancer cells. Furthermore, primary neurons are also compatible with BloC-Printing.
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Wang N, De Bock M, Decrock E, Bol M, Gadicherla A, Bultynck G, Leybaert L. Connexin targeting peptides as inhibitors of voltage- and intracellular Ca2+-triggered Cx43 hemichannel opening. Neuropharmacology 2013; 75:506-16. [DOI: 10.1016/j.neuropharm.2013.08.021] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Revised: 08/19/2013] [Accepted: 08/20/2013] [Indexed: 12/21/2022]
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Zhang X, Wang Q, Gablaski B, Zhang X, Lucchesi P, Zhao Y. A microdevice for studying intercellular electromechanical transduction in adult cardiac myocytes. LAB ON A CHIP 2013; 13:3090-7. [PMID: 23753064 PMCID: PMC3770274 DOI: 10.1039/c3lc50414j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Intercellular electromechanical transduction in adult cardiac myocytes plays an important role in regulating heart function. The efficiency of intercellular electromechanical transduction has so far been investigated only to a limited extent, which is largely due to the lack of appropriate tools that can quantitatively assess the contractile performance of interconnected adult cardiac myocytes. In this paper we report a microengineered device that is capable of applying electrical stimulation to the selected adult cardiac myocyte in a longitudinally connected cell doublet and quantifying the intercellular electromechanical transduction by measuring the contractile performance of stimulated and un-stimulated cells in the same doublet. The capability of applying selective electrical stimulation on only one cell in the doublet is validated by examining cell contractile performance while blocking the intercellular communication. Quantitative assessment of cell contractile performance in isolated adult cardiac myocytes is performed by measuring the change in cell length. The proof-of-concept assessment of gap junction performance shows that the device is useful in studying the efficiency of gap junctions in adult cardiac myocytes, which is most relevant to the synchronized pumping performance of native myocardium. Collectively, this work provides a quantitative tool for studying intercellular electromechanical transduction and is expected to develop a comprehensive understanding of the role of intercellular communication in various heart diseases.
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Affiliation(s)
- Xu Zhang
- Laboratory for Biomedical Microsystems, Department of Biomedical Engineering, The Ohio State University, Columbus, OH, 43210 USA
| | - Qian Wang
- Laboratory for Biomedical Microsystems, Department of Biomedical Engineering, The Ohio State University, Columbus, OH, 43210 USA
| | - Brian Gablaski
- Center for Cardiovascular and Pulmonary Research, Nationwide Children’s Hospital, Columbus, OH, 43205 USA
| | - Xiaojin Zhang
- Center for Cardiovascular and Pulmonary Research, Nationwide Children’s Hospital, Columbus, OH, 43205 USA
| | - Pamela Lucchesi
- Center for Cardiovascular and Pulmonary Research, Nationwide Children’s Hospital, Columbus, OH, 43205 USA
| | - Yi Zhao
- Laboratory for Biomedical Microsystems, Department of Biomedical Engineering, The Ohio State University, Columbus, OH, 43210 USA
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Benninger RK, Piston DW. Two-photon excitation microscopy for the study of living cells and tissues. CURRENT PROTOCOLS IN CELL BIOLOGY 2013; Chapter 4:4.11.1-4.11.24. [PMID: 23728746 PMCID: PMC4004770 DOI: 10.1002/0471143030.cb0411s59] [Citation(s) in RCA: 128] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Two-photon excitation microscopy is an alternative to confocal microscopy that provides advantages for three-dimensional and deep tissue imaging. This unit will describe the basic physical principles behind two-photon excitation and discuss the advantages and limitations of its use in laser-scanning microscopy. The principal advantages of two-photon microscopy are reduced phototoxicity, increased imaging depth, and the ability to initiate highly localized photochemistry in thick samples. Practical considerations for the application of two-photon microscopy will then be discussed, including recent technological advances. This unit will conclude with some recent applications of two-photon microscopy that highlight the key advantages over confocal microscopy and the types of experiments which would benefit most from its application.
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Kovac J, Gerardin Y, Voldman J. Image-predicated sorting of adherent cells using photopatterned hydrogels. Adv Healthc Mater 2013; 2:552-6. [PMID: 23184713 PMCID: PMC3760966 DOI: 10.1002/adhm.201200196] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Indexed: 12/18/2022]
Affiliation(s)
- J. Kovac
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA 02139 (USA)
| | - Ylaine Gerardin
- Department of Systems Biology, Harvard University, Cambridge, MA 02138 (USA)
| | - J. Voldman
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA 02139 (USA)
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Schumacher JA, Hsieh YW, Chen S, Pirri JK, Alkema MJ, Li WH, Chang C, Chuang CF. Intercellular calcium signaling in a gap junction-coupled cell network establishes asymmetric neuronal fates in C. elegans. Development 2013; 139:4191-201. [PMID: 23093425 DOI: 10.1242/dev.083428] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The C. elegans left and right AWC olfactory neurons specify asymmetric subtypes, one default AWC(OFF) and one induced AWC(ON), through a stochastic, coordinated cell signaling event. Intercellular communication between AWCs and non-AWC neurons via a NSY-5 gap junction network coordinates AWC asymmetry. However, the nature of intercellular signaling across the network and how individual non-AWC cells in the network influence AWC asymmetry is not known. Here, we demonstrate that intercellular calcium signaling through the NSY-5 gap junction neural network coordinates a precise 1AWC(ON)/1AWC(OFF) decision. We show that NSY-5 gap junctions in C. elegans cells mediate small molecule passage. We expressed vertebrate calcium-buffer proteins in groups of cells in the network to reduce intracellular calcium levels, thereby disrupting intercellular communication. We find that calcium in non-AWC cells of the network promotes the AWC(ON) fate, in contrast to the autonomous role of calcium in AWCs to promote the AWC(OFF) fate. In addition, calcium in specific non-AWCs promotes AWC(ON) side biases through NSY-5 gap junctions. Our results suggest a novel model in which calcium has dual roles within the NSY-5 network: autonomously promoting AWC(OFF) and non-autonomously promoting AWC(ON).
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Affiliation(s)
- Jennifer A Schumacher
- Division of Developmental Biology, Children's Hospital Medical Center Research Foundation, 240 Albert Sabin Way, Cincinnati, OH 45229, USA
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Abstract
Intercellular calcium (Ca(2+)) waves (ICWs) represent the propagation of increases in intracellular Ca(2+) through a syncytium of cells and appear to be a fundamental mechanism for coordinating multicellular responses. ICWs occur in a wide diversity of cells and have been extensively studied in vitro. More recent studies focus on ICWs in vivo. ICWs are triggered by a variety of stimuli and involve the release of Ca(2+) from internal stores. The propagation of ICWs predominately involves cell communication with internal messengers moving via gap junctions or extracellular messengers mediating paracrine signaling. ICWs appear to be important in both normal physiology as well as pathophysiological processes in a variety of organs and tissues including brain, liver, retina, cochlea, and vascular tissue. We review here the mechanisms of initiation and propagation of ICWs, the key intra- and extracellular messengers (inositol 1,4,5-trisphosphate and ATP) mediating ICWs, and the proposed physiological functions of ICWs.
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Affiliation(s)
- Luc Leybaert
- Department of Basic Medical Sciences, Physiology Group, Faculty of Medicine & Health Sciences, Ghent University, Ghent, Belgium.
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41
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Abstract
Photoactivatable fluorophores switch from a nonemissive to an emissive state upon illumination at an activating wavelength and then emit after irradiation at an exciting wavelength. The interplay of such activation and excitation events can be exploited to switch fluorescence on in a defined region of space at a given interval of time. In turn, the spatiotemporal control of fluorescence translates into the opportunity to implement imaging and spectroscopic schemes that are not possible with conventional fluorophores. Specifically, photoactivatable fluorophores permit the monitoring of dynamic processes in real time as well as the reconstruction of images with subdiffraction resolution. These promising applications can have a significant impact on the characterization of the structures and functions of biomolecular systems. As a result, strategies to implement mechanisms for fluorescence photoactivation with synthetic fluorophores are particularly valuable. In fact, a number of versatile operating principles have already been identified to activate the fluorescence of numerous members of the main families of synthetic dyes. These methods are based on either the irreversible cleavage of covalent bonds or the reversible opening and closing of rings. This paper overviews the fundamental mechanisms that govern the behavior of these photoresponsive systems, illustrates structural designs for fluorescence photoactivation, and provides representative examples of photoactivatable fluorophores in actions.
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Affiliation(s)
- Françisco M. Raymo
- Laboratory for Molecular Photonics, Department of Chemistry, University of Miami, 1301 Memorial Drive, Coral Gables, FL 33146-0431, USA
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Li WH, Zheng G. Photoactivatable fluorophores and techniques for biological imaging applications. Photochem Photobiol Sci 2012; 11:460-71. [PMID: 22252510 PMCID: PMC3677749 DOI: 10.1039/c2pp05342j] [Citation(s) in RCA: 100] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Accepted: 11/28/2011] [Indexed: 11/21/2022]
Abstract
Photoactivatable fluorophores (PAFs) are powerful imaging probes for tracking molecular and cellular dynamics with high spatiotemporal resolution in biological systems. Recent developments in biological microscopy have raised new demands for engineering new PAFs with improved properties, such as high two photon excitation efficiency, reversibility, cellular delivery and targeting. Here we review the history and some of the recent developments in this area, emphasizing our efforts in developing a new class of caged coumarins and related imaging methods for studying dynamic cell-cell communication through gap junction channels, and in extending the application of these caged coumarins to new areas including spatiotemporal control of microRNA activity in vivo.
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Affiliation(s)
- Wen-hong Li
- Departments of Cell Biology and of Biochemistry, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390, USA.
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Regulation of Intercellular Calcium Signaling Through Calcium Interactions with Connexin-Based Channels. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 740:777-94. [DOI: 10.1007/978-94-007-2888-2_34] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Hodson DJ, Romanò N, Schaeffer M, Fontanaud P, Lafont C, Fiordelisio T, Mollard P. Coordination of calcium signals by pituitary endocrine cells in situ. Cell Calcium 2011; 51:222-30. [PMID: 22172406 DOI: 10.1016/j.ceca.2011.11.007] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Revised: 11/08/2011] [Accepted: 11/17/2011] [Indexed: 12/20/2022]
Abstract
The pulsatile secretion of hormones from the mammalian pituitary gland drives a wide range of homeostatic responses by dynamically altering the functional set-point of effector tissues. To accomplish this, endocrine cell populations residing within the intact pituitary display large-scale changes in coordinated calcium-spiking activity in response to various hypothalamic and peripheral inputs. Although the pituitary gland is structurally compartmentalized into specific and intermingled endocrine cell networks, providing a clear morphological basis for such coordinated activity, the mechanisms which facilitate the timely propagation of information between cells in situ remain largely unexplored. Therefore, the aim of the current review is to highlight the range of signalling modalities known to be employed by endocrine cells to coordinate intracellular calcium rises, and discuss how these mechanisms are integrated at the population level to orchestrate cell function and tissue output.
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Affiliation(s)
- David J Hodson
- CNRS, UMR-5203, Institut de Génomique Fonctionnelle, F-34000 Montpellier, France.
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Upham BL. Role of integrative signaling through gap junctions in toxicology. ACTA ACUST UNITED AC 2011; Chapter 2:Unit2.18. [PMID: 21400682 DOI: 10.1002/0471140856.tx0218s47] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Gap junctional intercellular communication (GJIC) plays a central role in coordinating signal-transduction pathways that control gene expression inside of cells with those of neighboring cells in maintaining the homeostasis of a tissue. The normal homeostatic set point of gap junctions within tissues is in an open state, and although transient closure of gap junctions in response to mitogenic effectors is normal, chronic closure of channels by continuous exposure to environmental and food-borne contaminants can result in adverse health effects such as cancer, teratogenesis, reproductive dysfunction, neuropathies, and cardiac arrhythmias. GJIC is the primary means of integrating signal transduction pathways controlling gene expression between contiguous cells. Thus, bioassay systems that can measure GJIC offer a central, more biosystems approach to assessing the potential for toxicants to epigenetically alter gene expression.
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Affiliation(s)
- Brad L Upham
- Michigan State University, East Lansing, Michigan, USA
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Ye N, Bathany C, Hua SZ. Assay for molecular transport across gap junction channels in one-dimensional cell arrays. LAB ON A CHIP 2011; 11:1096-1101. [PMID: 21293824 DOI: 10.1039/c0lc00350f] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Transport across gap junction channels (GJCs) between neighboring cells is critical to synchronizing cell's electrical and metabolic activities and maintaining cell homeostasis. Here we present a non-invasive microfluidic method to measure molecular diffusion across GJCs in multiple 1D cell arrays in real time. Using the chip, selective loading of a membrane permeant fluorescence dye (carboxyfluorescein) in Normal Rat Kidney (NRK) cells shows that the dye was able to diffuse through three cells along single cell chains in ∼35 minutes. Application of 100 µM 2-aminoethoxydiphenyl borate (2-APB) reversibly inhibits connexin-43 gap junctions in NRK cells; 0.8 mM 1-heptanol inhibits the diffusion partially. The method offers rapid exchange of reagents, enabling sequential screening of multiple gap junction specific drugs with only one preparation of cells. It is capable of measuring gap junction mediated diffusion between single cells.
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Affiliation(s)
- Nannan Ye
- Department of Physiology and Biophysics, SUNY-Buffalo, Buffalo, NY 14260, USA
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Chloral hydrate decreases gap junction communication in rat liver epithelial cells. Cell Biol Toxicol 2011; 27:207-16. [PMID: 21243523 DOI: 10.1007/s10565-011-9182-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2009] [Accepted: 01/06/2011] [Indexed: 12/16/2022]
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Hayar A, Charlesworth A, Garcia-Rill E. Oocyte triplet pairing for electrophysiological investigation of gap junctional coupling. J Neurosci Methods 2010; 188:280-6. [PMID: 20230857 PMCID: PMC2859429 DOI: 10.1016/j.jneumeth.2010.03.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Revised: 03/04/2010] [Accepted: 03/05/2010] [Indexed: 11/19/2022]
Abstract
Gap junctions formed by expressing connexin subunits in Xenopus oocytes provide a valuable tool for revealing the gating properties of intercellular gap junctions in electrically coupled cells. We describe a new method that consists of simultaneous triple recordings from 3 apposed oocytes expressing exogenous connexins. The advantages of this method are that in one single experiment, 1 oocyte serves as control while a pair of oocytes, which have been manipulated differently, may be tested for different gap junctional properties. Moreover, we can study simultaneously the gap junctional coupling of 3 different pairs of oocytes in the same preparation. If the experiment consists of testing the effect of a single drug, this approach will reduce the time required, as background coupling in control pairs of oocytes does not need to be measured separately as with the conventional 2 oocyte pairing. The triplet approach also increases confidence that any changes seen in junctional communication are due to the experimental treatment and not variation in the preparation of oocytes or execution of the experiment. In this study, we show the example of testing the gap junctional properties among 3 oocytes, 2 of which are expressing rat connexin36.
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Affiliation(s)
- Abdallah Hayar
- Dept of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Center for Translational Neuroscience, Little Rock, AR 72205, United States.
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Dieriks B, De Vos WH, Derradji H, Baatout S, Van Oostveldt P. Medium-mediated DNA repair response after ionizing radiation is correlated with the increase of specific cytokines in human fibroblasts. Mutat Res 2010; 687:40-48. [PMID: 20080111 DOI: 10.1016/j.mrfmmm.2010.01.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Radiation induced bystander effects, either protective or adverse, have been identified in a variety of cells and for different endpoints. They are thought to arise from communication between cells through direct cell-cell contacts and via transmissible molecules secreted into the medium by targeted cells. We have investigated medium-mediated damage response in human dermal fibroblasts (HDF) after exposure to ionizing irradiation. We show that HDF experience an elevated level of double stranded DNA damage repair response when incubated with conditioned growth medium of irradiated cells. The magnitude of this response is much lower than observed for directly irradiated cells and is proportional to the radiation dose, as is its persistence across time. Since secretion of cytokines is one of the possible pathways linking targeted and non-targeted cells a multiplex analysis was performed. Four cytokines - IL6, IL8, MCP-1 and RANTES - were identified in the growth medium of irradiated cells after exposure to X-rays (2Gy). These cytokines were significantly upregulated and each cytokine showed differential upregulation kinetics. Finally we performed a functional analysis to see if IL6 and MCP-1 could induce gammaH2AX foci formation. IL6 caused a significant increase in spot occupancy compared to controls. Although only indicative MCP-1 appears to have the opposite effect as it caused a drop in spot occupancy. The combined addition of these two cytokines produced no significant response was observed. Both IL6 and MCP-1 have an effect on the gammaH2AX spot occupancy possibly linking these cytokines to the bystander response.
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Affiliation(s)
- Birger Dieriks
- Laboratory for Biochemistry and Molecular Cytology, Department of Molecular Biotechnology, Ghent University, Coupure Links 653, 9000 Gent, Belgium.
| | - Winnok H De Vos
- Laboratory for Biochemistry and Molecular Cytology, Department of Molecular Biotechnology, Ghent University, Coupure Links 653, 9000 Gent, Belgium
| | - Hanane Derradji
- Laboratory Molecular & Cellular Biology, Radiobiology Unit, Belgian Nuclear Research Center, SCK CEN, Boeretang 200, 2400 Mol, Belgium
| | - Sarah Baatout
- Laboratory Molecular & Cellular Biology, Radiobiology Unit, Belgian Nuclear Research Center, SCK CEN, Boeretang 200, 2400 Mol, Belgium
| | - Patrick Van Oostveldt
- Laboratory for Biochemistry and Molecular Cytology, Department of Molecular Biotechnology, Ghent University, Coupure Links 653, 9000 Gent, Belgium
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Lin W, Long L, Tan W, Chen B, Yuan L. Coumarin-Caged Rosamine Probes Based on a Unique Intramolecular Carbon-Carbon Spirocyclization. Chemistry 2010; 16:3914-7. [DOI: 10.1002/chem.201000015] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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