944 results match your criteria gating interface


Electric field control of superconductivity at the LaAlO/KTaO(111) interface.

Science 2021 May;372(6543):721-724

Interdisciplinary Center for Quantum Information, State Key Laboratory of Modern Optical Instrumentation, and Zhejiang Province Key Laboratory of Quantum Technology and Device, Department of Physics, Zhejiang University, Hangzhou 310027, China.

The oxide interface between LaAlO and KTaO(111) can harbor a superconducting state. We report that by applying a gate voltage () across KTaO, the interface can be continuously tuned from superconducting into insulating states, yielding a dome-shaped - dependence, where is the transition temperature. The electric gating has only a minor effect on carrier density but a strong one on mobility. Read More

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Interfacial Gated Graphene Photodetector with Broadband Response.

ACS Appl Mater Interfaces 2021 May 8. Epub 2021 May 8.

Department of Physics, State Key Laboratory of Low-Dimensional Quantum Physics and Tsinghua-Foxconn Nanotechnology Research Center, Tsinghua University, Beijing 100084, P. R. China.

A much stronger interfacial gating effect was observed in the graphene/HfO/Si photodetector when compared with that in the graphene/SiO/Si photodetector. We found that this improvement was due to the higher interface state density at the HfO/Si interface and the higher dielectric constant of the HfO layer. The photoresponsivity of the graphene/HfO/Si photodetector is as high as 45. Read More

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A surface charge governed nanofluidic diode based on a single polydimethylsiloxane (PDMS) nanochannel.

Authors:
Jun Li Dongqing Li

J Colloid Interface Sci 2021 Aug 24;596:54-63. Epub 2021 Mar 24.

Department of Mechanical and Mechatronics Engineering, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada. Electronic address:

Hypothesis: Nanofluidic diodes have attracted intense attention recently. Commonly used materials to design these devices are membrane-based short nanopores and aligned Carbon nanotube bundles. It is highly desirable and very challenging to develop a nanofluidic diode based on a single PDMS nanochannel which is easier to be introduced into an integrated electronic system on a chip. Read More

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Nanopore-based desalination subject to simultaneously applied pressure gradient and gating potential.

J Colloid Interface Sci 2021 Jul 15;594:737-744. Epub 2021 Mar 15.

Department of Chemical Engineering, National Taiwan University, Taiwan; Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan. Electronic address:

The performance of a dielectric membrane in desalting is assessed by considering a cylindrical nanopore, surface modified by a dielectric layer, subject to simultaneously applied pressure gradient and gating potential. The charged conditions of the nanopore can be tuned by modulating the applied gating potential so that it can be used for rejecting different types of salt. In general, the thinner the dielectric layer and/or the larger its dielectric constant the better the salt rejection performance. Read More

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Signal transduction through Cys-loop receptors is mediated by the nonspecific bumping of closely apposed domains.

Proc Natl Acad Sci U S A 2021 Apr;118(14)

Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801;

One of the most fundamental questions in the field of Cys-loop receptors (pentameric ligand-gated ion channels, pLGICs) is how the affinity for neurotransmitters and the conductive/nonconductive state of the transmembrane pore are correlated despite the ∼60-Å distance between the corresponding domains. Proposed mechanisms differ, but they all converge into the idea that interactions between wild-type side chains across the extracellular-transmembrane-domain (ECD-TMD) interface are crucial for this phenomenon. Indeed, the successful design of fully functional chimeras that combine intact ECD and TMD modules from different wild-type pLGICs has commonly been ascribed to the residual conservation of sequence that exists at the level of the interfacial loops even between evolutionarily distant parent channels. Read More

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Ionic Transport and Robust Switching Properties of the Confined Self-Assembled Block Copolymer/Homopolymer in Asymmetric Nanochannels.

ACS Appl Mater Interfaces 2021 Mar 18;13(12):14507-14517. Epub 2021 Mar 18.

Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education, School of Chemistry and Environment, Beihang University, Beijing 100191, People's Republic of China.

The self-assembly of block copolymers in a confined space has been proven to be a facile and robust strategy for fabricating assembled structures with various potential applications. Herein, we employed a new pH-responsive polymer self-assembly method to regulate ion transport inside artificial nanochannels. The track-etched asymmetric nanochannels were functionalized with PS--P4VP/hPS blend polymers, and the ionic conductance and rectification properties of the proposed system were investigated. Read More

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Evaporation in nano/molecular materials.

Adv Colloid Interface Sci 2021 Apr 23;290:102385. Epub 2021 Feb 23.

Department of Mechanical Engineering, University of Houston, 4726 Calhoun Rd, Houston, TX 77204, USA. Electronic address:

Evaporation is a physical phenomenon with fundamental significance to both nature and technology ranging from plant transpiration to DNA engineering. Various analytical and empirical relationships have been proposed to characterize evaporation kinetics at macroscopic scales. However, theoretical models to describe the kinetics of evaporation from nano and sub-nanometer (molecular) confinements are absent. Read More

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Lipid regulation of hERG1 channel function.

Nat Commun 2021 03 3;12(1):1409. Epub 2021 Mar 3.

Centre for Molecular Simulation and Department of Biological Sciences, 507 Campus Drive, University of Calgary, Calgary, AB, Canada.

The lipid regulation of mammalian ion channel function has emerged as a fundamental mechanism in the control of electrical signalling and transport specificity in various cell types. In this work, we combine molecular dynamics simulations, mutagenesis, and electrophysiology to provide mechanistic insights into how lipophilic molecules (ceramide-sphingolipid probe) alter gating kinetics and K currents of hERG1. We show that the sphingolipid probe induced a significant left shift of activation voltage, faster deactivation rates, and current blockade comparable to traditional hERG1 blockers. Read More

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Fast searches of large collections of single-cell data using scfind.

Nat Methods 2021 03 1;18(3):262-271. Epub 2021 Mar 1.

Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, UK.

Single-cell technologies have made it possible to profile millions of cells, but for these resources to be useful they must be easy to query and access. To facilitate interactive and intuitive access to single-cell data we have developed scfind, a single-cell analysis tool that facilitates fast search of biologically or clinically relevant marker genes in cell atlases. Using transcriptome data from six mouse cell atlases, we show how scfind can be used to evaluate marker genes, perform in silico gating, and identify both cell-type-specific and housekeeping genes. Read More

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Zero-Bias Conductance Peaks Effectively Tuned by Gating-Controlled Rashba Spin-Orbit Coupling.

Phys Rev Lett 2021 Feb;126(5):057701

International Center for Quantum Design of Functional Materials (ICQD), Hefei National Laboratory for Physical Sciences at the Microscale, and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.

Zero-bias conductance peaks (ZBCPs) can manifest a number of notable physical phenomena and thus provide critical characteristics to the underlying electronic systems. Here, we report observations of pronounced ZBCPs in hybrid junctions composed of an oxide heterostructure LaAlO_{3}/SrTiO_{3} and an elemental superconductor Nb, where the two-dimensional electron system (2DES) at the LaAlO_{3}/SrTiO_{3} interface is known to accommodate gate-tunable Rashba spin-orbit coupling (SOC). Remarkably, the ZBCPs exhibit a domelike dependence on the gate voltage, which correlates strongly with the nonmonotonic gate dependence of the Rashba SOC in the 2DES. Read More

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February 2021

Tuning Protein Discrimination Through Altering the Sampling Interface Formed between the Analyte and the OmpG Nanopore.

ACS Sens 2021 03 18;6(3):1286-1294. Epub 2021 Feb 18.

Molecular and Cellular Biology Program, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States.

Nanopore sensors capable of distinguishing homologous protein analytes are highly desirable tools for proteomics research and disease diagnostics. Recently, an engineered outer membrane protein G (OmpG) nanopore with a high-affinity ligand attached to a gating loop 6 showed specificity for distinguishing homologous proteins in complex mixtures. Here, we report the development of OmpG nanopores with the other six loops used as the anchoring point to host an affinity ligand for protein sensing. Read More

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Ionically Gated Small-Molecule OPV: Interfacial Doping of Charge Collector and Transport Layer.

ACS Appl Mater Interfaces 2021 Feb 15;13(7):8606-8619. Epub 2021 Feb 15.

ITMO University, Kronverkskiy pr. 49, St. Petersburg 197101, Russia.

We demonstrate an improvement in the performance of organic photovoltaic (OPV) systems based on small molecules by ionic gating via controlled reversible n-doping of multi-wall carbon nanotubes (MWCNTs) coated on fullerene electron transport layers (ETLs): C and C. Such electric double-layer charging (EDLC) doping, achieved by ionic liquid (IL) charging, allows tuning of the electronic concentration in MWCNTs and the fullerene planar acceptor layers, increasing it by orders of magnitude. This leads to the decrease of the series and increase of the shunt resistances of OPVs and allows use of thick (up to 200 nm) ETLs, increasing the durability of OPVs. Read More

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February 2021

VDAC-A Primal Perspective.

Int J Mol Sci 2021 Feb 8;22(4). Epub 2021 Feb 8.

Department of Physiology, Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD 20201, USA.

The evolution of the eukaryotic cell from the primal endosymbiotic event involved a complex series of adaptations driven primarily by energy optimization. Transfer of genes from endosymbiont to host and concomitant expansion (by infolding) of the endosymbiont's chemiosmotic membrane greatly increased output of adenosine triphosphate (ATP) and placed selective pressure on the membrane at the host-endosymbiont interface to sustain the energy advantage. It is hypothesized that critical functions at this interface (metabolite exchange, polypeptide import, barrier integrity to proteins and DNA) were managed by a precursor β-barrel protein ("pβB") from which the voltage-dependent anion-selective channel (VDAC) descended. Read More

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February 2021

Modulating the Mechanical Activation of TRPV4 at the Cell-Substrate Interface.

Front Bioeng Biotechnol 2020 18;8:608951. Epub 2021 Jan 18.

EMBL Australia Node in Single Molecule Science and Cellular and Systems Physiology, Faculty of Medicine, School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia.

Ion channels activated by mechanical inputs are important force sensing molecules in a wide array of mammalian cells and tissues. The transient receptor potential channel, TRPV4, is a polymodal, nonselective cation channel that can be activated by mechanical inputs but only if stimuli are applied directly at the interface between cells and their substrate, making this molecule a context-dependent force sensor. However, it remains unclear how TRPV4 is activated by mechanical inputs at the cell-substrate interface, which cell intrinsic and cell extrinsic parameters might modulate the mechanical activation of the channel and how mechanical activation differs from TRPV4 gating in response to other stimuli. Read More

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January 2021

Influence of the Electrolyte Salt Concentration on DNA Detection with Graphene Transistors.

Biosensors (Basel) 2021 Jan 17;11(1). Epub 2021 Jan 17.

Food Quality and Safety Group, International Iberian Nanotechnology Laboratory (INL), Av. Mestre José Veiga, 4715-330 Braga, Portugal.

Liquid-gated Graphene Field-Effect Transistors (GFET) are ultrasensitive bio-detection platforms carrying out the graphene's exceptional intrinsic functionalities. Buffer and dilution factor are prevalent strategies towards the optimum performance of the GFETs. However, beyond the Debye length (λD), the role of the graphene-electrolytes' ionic species interactions on the DNA behavior at the nanoscale interface is complicated. Read More

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January 2021

α Subunit Histidine 55 at the Interface between Extracellular and Transmembrane Domains Affects Preactivation and Desensitization of the GABA Receptor.

ACS Chem Neurosci 2021 02 20;12(3):562-572. Epub 2021 Jan 20.

Department of Biophysics and Neuroscience, Wroclaw Medical University, Chalubinskiego 3a, Wroclaw, Dolnoślaskie 50-368, Poland.

The GABA receptor is a member of the Cys-loop family and plays a crucial role in the adult mammalian brain inhibition. Although the static structure of this receptor is emerging, the molecular mechanisms underlying its conformational transitions remain elusive. It is known that in the Cys-loop receptors, the interface between extracellular and transmembrane domains plays a key role in transmitting the "activation wave" down to the channel gate in the pore. Read More

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February 2021

Engineering an Indium Selenide van der Waals Interface for Multilevel Charge Storage.

ACS Appl Mater Interfaces 2021 Jan 14;13(3):4618-4625. Epub 2021 Jan 14.

Center for Condensed Matter Sciences, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan.

As the continuous miniaturization of floating-gate transistors approaches a physical limit, new innovations in device architectures, working principles, and device materials are in high demand. This study demonstrated a nonvolatile memory structure with multilevel data storage that features a van der Waals gate architecture made up of a partially oxidized surface layer/indium selenide (InSe) van der Waals interface. The key functionality of this proof-of-concept device is provided through the generation of charge-trapping sites via an indirect oxygen plasma treatment on the InSe surface layer. Read More

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January 2021

Distinct lipid bilayer compositions have general and protein-specific effects on K+ channel function.

J Gen Physiol 2021 Feb;153(2)

Membrane Biophysics, Technische Universität Darmstadt, Darmstadt, Germany.

It has become increasingly apparent that the lipid composition of cell membranes affects the function of transmembrane proteins such as ion channels. Here, we leverage the structural and functional diversity of small viral K+ channels to systematically examine the impact of bilayer composition on the pore module of single K+ channels. In vitro-synthesized channels were reconstituted into phosphatidylcholine bilayers ± cholesterol or anionic phospholipids (aPLs). Read More

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February 2021

The SuperCam Instrument Suite on the NASA Mars 2020 Rover: Body Unit and Combined System Tests.

Space Sci Rev 2021 21;217(1). Epub 2020 Dec 21.

University of Basque Country, UPV/EHU, Bilbao, Spain.

The SuperCam instrument suite provides the Mars 2020 rover, Perseverance, with a number of versatile remote-sensing techniques that can be used at long distance as well as within the robotic-arm workspace. These include laser-induced breakdown spectroscopy (LIBS), remote time-resolved Raman and luminescence spectroscopies, and visible and infrared (VISIR; separately referred to as VIS and IR) reflectance spectroscopy. A remote micro-imager (RMI) provides high-resolution color context imaging, and a microphone can be used as a stand-alone tool for environmental studies or to determine physical properties of rocks and soils from shock waves of laser-produced plasmas. Read More

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December 2020

Gated Proton Release during Radical Transfer at the Subunit Interface of Ribonucleotide Reductase.

J Am Chem Soc 2021 01 23;143(1):176-183. Epub 2020 Dec 23.

Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States.

The class Ia ribonucleotide reductase of requires strict regulation of long-range radical transfer between two subunits, α and β, through a series of redox-active amino acids (Y•[β] ↔ W?[β] ↔ Y[β] ↔ Y[α] ↔ Y[α] ↔ C[α]). Nowhere is this more precarious than at the subunit interface. Here, we show that the oxidation of Y is regulated by proton release involving a specific residue, E[β], which is part of a water channel at the subunit interface for rapid proton transfer to the bulk solvent. Read More

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January 2021

Transport Phenomena in Nano/Molecular Confinements.

ACS Nano 2020 Nov 30. Epub 2020 Nov 30.

Department of Mechanical Engineering, University of Houston, 4726 Calhoun Road, Houston, Texas 77204, United States.

The transport of fluid and ions in nano/molecular confinements is the governing physics of a myriad of embodiments in nature and technology including human physiology, plants, energy modules, water collection and treatment systems, chemical processes, materials synthesis, and medicine. At nano/molecular scales, the confinement dimension approaches the molecular size and the transport characteristics deviates significantly from that at macro/micro scales. A thorough understanding of physics of transport at these scales and associated fluid properties is undoubtedly critical for future technologies. Read More

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November 2020

Characterization of various geometric arrangements of "air-assisted" flow gating interfaces for capillary electrophoresis.

Electrophoresis 2021 Mar 3;42(6):749-755. Epub 2020 Dec 3.

Department of Hygiene, Third Faculty of Medicine, Charles University, Prague, Czechia.

For connecting flow-through analytical methods with capillary electrophoresis, a chip working in the air-assisted flow gating interface regime is cast from poly(dimethylsiloxane). In the injection space, the exit from the delivery capillary is placed close to the entrance to the separation capillary. Prior to injecting the sample into the separation capillary, the background electrolyte is forced out of the injection space by a stream of air. Read More

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Interaction between GABA receptor α and β subunits at the N-terminal peripheral regions is crucial for receptor binding and gating.

Biochem Pharmacol 2021 01 13;183:114338. Epub 2020 Nov 13.

Department of Biophysics and Neuroscience, Wrocław Medical University, ul. Chałubińskiego 3A, 50-368 Wrocław, Poland; Department of Molecular Physiology and Neurobiology, University of Wrocław, ul. Sienkiewicza 21, 50-335 Wrocław, Poland. Electronic address:

Pentameric ligand gated ion channels (pLGICs) are crucial in electrochemical signaling but exact molecular mechanisms of their activation remain elusive. So far, major effort focused on the top-down molecular pathway between the ligand binding site and the channel gate. However, recent studies revealed that pLGIC activation is associated with coordinated subunit twisting in the membrane plane. Read More

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January 2021

Nanobubble-controlled nanofluidic transport.

Sci Adv 2020 Nov 13;6(46). Epub 2020 Nov 13.

Department of Electrical Engineering, Columbia University, New York, NY 10027, USA.

Nanofluidic platforms offering tunable material transport are applicable in biosensing, chemical detection, and filtration. Prior studies have achieved selective and controllable ion transport through electrical, optical, or chemical gating of complex nanostructures. Here, we mechanically control nanofluidic transport using nanobubbles. Read More

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November 2020

Structures and pH-sensing mechanism of the proton-activated chloride channel.

Nature 2020 12 4;588(7837):350-354. Epub 2020 Nov 4.

Department of Structural Biology, Van Andel Institute, Grand Rapids, MI, USA.

The proton-activated chloride channel (PAC) is active across a wide range of mammalian cells and is involved in acid-induced cell death and tissue injury. PAC has recently been shown to represent a novel and evolutionarily conserved protein family. Here we present two cryo-electron microscopy structures of human PAC in a high-pH resting closed state and a low-pH proton-bound non-conducting state. Read More

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December 2020

Super-Nernstian pH Sensor Based on Anomalous Charge Transfer Doping of Defect-Engineered Graphene.

Nano Lett 2021 Jan 2;21(1):34-42. Epub 2020 Nov 2.

SKKU Advanced Institute of Nanotechnology, Sungkyunkwan University, Suwon 440-746, South Korea.

The conventional pH sensor based on the graphene ion-sensitive field-effect transistor (Gr-ISFET), which operates with an electrostatic gating at the solution-graphene interface, cannot have a pH sensitivity above the Nernst limit (∼59 mV/pH). However, for accurate detection of the pH levels of an aqueous solution, an ultrasensitive pH sensor that can exceed the theoretical limit is required. In this study, a novel Gr-ISFET-based pH sensor is fabricated using proton-permeable defect-engineered graphene. Read More

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January 2021

Flexible Zinc Oxide Nanowire Array/Graphene Nanohybrid for High-Sensitivity Strain Detection.

ACS Omega 2020 Oct 15;5(42):27359-27367. Epub 2020 Oct 15.

Department of Physics and Astronomy, University of Kansas, Lawrence, Kansas 66045, United States.

A fully flexible strain sensor consisting of vertically aligned ZnO nanowires on graphene transferred on polyethylene terephthalate with prefabricated Au/Ti electrodes (ZnO-VANWs/Gr)/PET) has been obtained. The ZnO-VANWs were grown in solution using a seedless hydrothermal process and are single-crystalline of (0001) orientation that provides optimal piezoelectric gating on graphene when deformed mechanically. The change of the graphene channel conductance under such a piezoelectric gating through transduction of the mechanical deformation on the ZnO-VANWs/Gr was used to detect the strain induced by the deformation. Read More

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October 2020

Membrane thinning and lateral gating are consistent features of BamA across multiple species.

PLoS Comput Biol 2020 10 28;16(10):e1008355. Epub 2020 Oct 28.

School of Physics, Georgia Institute of Technology, Atlanta, Georgia, United States of America.

In Gram-negative bacteria, the folding and insertion of β-barrel outer membrane proteins (OMPs) to the outer membrane are mediated by the β-barrel assembly machinery (BAM) complex. Two leading models of this process have been put forth: the hybrid barrel model, which claims that a lateral gate in BamA's β-barrel can serve as a template for incoming OMPs, and the passive model, which claims that a thinned membrane near the lateral gate of BamA accelerates spontaneous OMP insertion. To examine the key elements of these two models, we have carried out 45. Read More

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October 2020

Design, Synthesis, and Pharmacological Evaluation of Analogues Derived from the PLEV Tetrapeptide as Protein-Protein Interaction Modulators of Voltage-Gated Sodium Channel 1.6.

J Med Chem 2020 10 15;63(20):11522-11547. Epub 2020 Oct 15.

The voltage-gated Na (Na) channel is the molecular determinant of excitability. Disruption of protein-protein interactions (PPIs) between Na1.6 and fibroblast growth factor 14 (FGF14) leads to impaired excitability of neurons in clinically relevant brain areas associated with channelopathies. Read More

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October 2020

Gap19, a Cx43 Hemichannel Inhibitor, Acts as a Gating Modifier That Decreases Main State Opening While Increasing Substate Gating.

Int J Mol Sci 2020 Oct 5;21(19). Epub 2020 Oct 5.

Department of Basic and Applied Medical Sciences-Physiology Group, Ghent University, 9000 Ghent, Belgium.

Cx43 hemichannels (HCs) are electrically and chemically gated transmembrane pores with low open probability and multiple conductance states, which makes kinetic studies of channel gating in large datasets challenging. Here, we developed open access software, named HemiGUI, to analyze HC gating transitions and investigated voltage-induced HC opening based on up to ≈4000 events recorded in HeLa-Cx43-overexpressing cells. We performed a detailed characterization of Cx43 HC gating profiles and specifically focused on the role of the C-terminal tail (CT) domain by recording the impact of adding an EGFP tag to the Cx43 CT end (Cx43-EGFP) or by supplying the Cx43 HC-inhibiting peptide Gap19 that interferes with CT interaction with the cytoplasmic loop (CL). Read More

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October 2020