Abstract:
:Ion channels and transporters are membrane proteins whose functions are driven by conformational changes. Classical biophysical techniques provide insight into either the structure or the function of these proteins, but a full understanding of their behavior requires a correlation of both these aspects in time. Patch-clamp and voltage-clamp fluorometry combine spectroscopic and electrophysiological techniques to simultaneously detect conformational changes and ionic currents across the membrane. Since its introduction, patch-clamp fluorometry has been responsible for invaluable advances in our knowledge of ion channel biophysics. Over the years, the technique has been applied to many different ion channel families to address several biophysical questions with a variety of spectroscopic approaches and electrophysiological configurations. This review illustrates the strength and the flexibility of patch-clamp fluorometry, demonstrating its potential as a tool for future research.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Kusch J,Zifarelli Gdoi
10.1016/j.bpj.2014.02.006subject
Has Abstractpub_date
2014-03-18 00:00:00pages
1250-7issue
6eissn
0006-3495issn
1542-0086pii
S0006-3495(14)00182-9journal_volume
106pub_type
杂志文章,评审abstract::Many biological processes exhibit complex kinetic behavior that involves a nontrivial distribution of rate constants. Characterization of the rate constant distribution is often critical for mechanistic understandings of these processes. However, it is difficult to extract a rate constant distribution from data measur...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.090688
更新日期:2006-12-01 00:00:00
abstract::Cardiac contraction and relaxation dynamics result from a set of simultaneously interacting Ca(2+) regulatory mechanisms. In this study, cardiocyte Ca(2+) dynamics were modeled using a set of six differential equations that were based on theories, equations, and parameters described in previous studies. Among the uniq...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(00)76276-X
更新日期:2000-07-01 00:00:00
abstract::Intracellular reactions are carried out in a crowded medium where the macromolecules occupy ∼40% of the total volume. This decrease in the available volume affects the activity of the reactants. Scaled particle theory is used for the estimation of the activity coefficients of the metabolites, and thereby for the asses...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2015.09.030
更新日期:2015-12-01 00:00:00
abstract::Numerous discussions of the relationship of the thermodynamics of radiation to photosynthesis have been published, but the results are often in disagreement or at best difficult to compare with one another. The recent treatment of maximal photosynthetic efficiencies by Ross and Calvin is here shown to be directly rela...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(69)86457-X
更新日期:1969-11-01 00:00:00
abstract::Spin-label saturation transfer EPR (ST-EPR) methods have been used to study the sickle hemoglobin (HbS) aggregation behaviors induced by slow deoxygenation at a constant temperature of 30 degrees C, and by a rapid temperature increase from 1 degree to 30 degrees C for fully deoxygenated HbS. For slow deoxygenation at ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(83)84394-X
更新日期:1983-06-01 00:00:00
abstract::In this article, we explore the information content of molecular force-field calculations. We make use of exhaustive lattice models of molecular conformations and reduced alphabet sequences to determine the relative resolving power of pairwise interaction-based force fields. We find that sequence-specific interactions...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.059618
更新日期:2005-11-01 00:00:00
abstract::The aquaglyceroporin GlpF is a transmembrane channel of Escherichia coli that facilitates the uptake of glycerol by the cell. Its high glycerol uptake rate is crucial for the cell to survive in very low glycerol concentrations. Although GlpF allows both influx and outflux of glycerol, its structure, similar to the str...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(03)74718-3
更新日期:2003-11-01 00:00:00
abstract::Tethered membranes have been proven during recent years to be a powerful and flexible biomimetic platform. We reported in a previous article on the design of a new architecture based on the self-assembly of a thiolipid on ultrasmooth gold substrates, which shows extremely good electrical sealing properties as well as ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.061374
更新日期:2005-09-01 00:00:00
abstract::Slow stretch ramps (velocity: 0.17 fiber lengths s-1) were imposed during fused tetanic contractions of intact muscle fibers of the frog (1.4-3.0 degrees C; sarcomere length: 2.12-2.21 microns). Instantaneous force-extension relations were derived both under isometric conditions and during slow stretch by applying fas...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(89)82689-X
更新日期:1989-08-01 00:00:00
abstract::The effect of cholesterol on phospholipid acyl chain packing in bilayers consisting of highly unsaturated acyl chains in the liquid crystalline phase was examined for a series of symmetrically and asymmetrically substituted phosphatidylcholines (PCs). The time-resolved fluorescence emission and decay of fluorescence a...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(98)77578-2
更新日期:1998-08-01 00:00:00
abstract::The investigation of the mechanism of protein folding is complicated by the context dependence of the rates of intramolecular contact formation. Methods based on site-specific labeling and ultrafast spectroscopic detection of fluorescence signals were developed for monitoring the rates of individual subdomain folding ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2017.01.037
更新日期:2017-05-09 00:00:00
abstract::Difference spectra between resting and excited nerve in the infrared region between 2000 and 1000 cm(-1) have been examined with a resolution of 0.5 cm(-1). Spectra were obtained with a modified Perkin-Elmer model 521 grating infrared spectrophotometer (Perkin-Elmer Corp., Instrument Div., Norwalk, Conn.), and the sig...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(72)86138-1
更新日期:1972-08-01 00:00:00
abstract::Current viral docking models have relied upon the assumption that bond formation and breakage are independent of viral and docking surface geometry, as well as the forces exerted on the bonds. This assumption, known as the equivalent site hypothesis (ESH), is examined in detail using a newly developed simulation techn...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.103.027813
更新日期:2004-06-01 00:00:00
abstract::We have measured the rates of insertion into, desorption from, and spontaneous interlayer translocation (flip-flop) in liquid-disordered and liquid-ordered phase lipid bilayer membranes, of the fluorescent phospholipid derivative NBD-dimyristoylphosphatidyl ethanolamine. This study made use of a recently described met...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.040576
更新日期:2004-07-01 00:00:00
abstract::A mesoscale model of DNA is presented (3SPN.1), extending the scheme previously developed by our group. Each nucleotide is mapped onto three interaction sites. Solvent is accounted for implicitly through a medium-effective dielectric constant and electrostatic interactions are treated at the level of Debye-Hückel theo...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2008.09.061
更新日期:2009-03-04 00:00:00
abstract::Pre-mRNA processing protein 40 (Prp40) is a nuclear protein that has a role in pre-mRNA splicing. Prp40 possesses two leucine-rich nuclear export signals, but little is known about the function of Prp40 in the export process. Another protein that has a role in protein export is centrin, a member of the EF-hand superfa...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2017.03.042
更新日期:2017-06-20 00:00:00
abstract::A complete description of protein structure and function must include a proper treatment of mechanisms that lead to cooperativity. The helix/coil transition serves as a simple example of a cooperative folding process, commonly described by a nucleation-propagation mechanism. The prevalent view is that coil structure m...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2009.09.013
更新日期:2009-12-02 00:00:00
abstract::This is the first in a series of four papers in which we present the numerical simulation of the application of the voltage clamp technique to excitable cells. In this paper we describe the application of the Crank-Nicolson (1947) method for the solution of the parabolic partial differential equations that describe a ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(75)85788-2
更新日期:1975-01-01 00:00:00
abstract::In total internal reflection fluorescence microscopy (TIRFM), fluorophores near a surface can be excited with evanescent waves, which decay exponentially with distance from the interface. Penetration depths of evanescent waves from 60 nm to 300 nm were generated by varying the angle of incidence of a laser beam. With ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(00)76808-1
更新日期:2000-05-01 00:00:00
abstract::Although the majority of free cellular cholesterol is present in the plasma membrane, cholesterol homeostasis is principally regulated through sterol-sensing proteins that reside in the cholesterol-poor endoplasmic reticulum (ER). In response to acute cholesterol loading or depletion, there is rapid equilibration betw...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2013.08.042
更新日期:2013-10-15 00:00:00
abstract::We have analyzed flash-induced period-four damped oscillation of oxygen evolution and chlorophyll fluorescence with the aid of a kinetic model of photosystem II. We have shown that, for simulation of the period-four oscillatory behavior of oxygen evolution, it is essential to consider the so-called intermediate S-stat...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.122861
更新日期:2008-04-01 00:00:00
abstract::The extracellular space of the brain is the heterogeneous porous medium formed by the spaces between the brain cells. Diffusion in this interstitial space is the mechanism by which glucose and oxygen are delivered to the brain cells from the vascular system. It is also a medium for the transport of certain information...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.095547
更新日期:2007-05-15 00:00:00
abstract::The serine protease inhibitor antithrombin undergoes extensive conformational changes during functional interaction with its target proteases. Changes include insertion of the reactive loop region into a beta-sheet structure in the protein core. We explore the possibility that these changes are linked to water transfe...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(98)77548-4
更新日期:1998-08-01 00:00:00
abstract::Titin is a very large (>3 MDa) protein found in striated muscle where it is believed to participate in myogenesis and passive tension. A prominent feature in the A-band portion of titin is the presence of an 11-domain super-repeat of immunoglobulin superfamily and fibronectin-type-III-like domains. Seven overlapping c...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/s0006-3495(01)75811-0
更新日期:2001-09-01 00:00:00
abstract::Multiple molecular dynamics simulations of bacterioopsin pulling from its C-terminus show that its alpha-helices unfold individually. In the first metastable state observed in the simulations, helix G is unfolded at its C-terminal segment while the rest of helix G (residues 200-216) is folded and opposes resistance be...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.088591
更新日期:2006-11-01 00:00:00
abstract::A beat-to-beat variation in the cardiac action potential duration is a phenomenon known as alternans. Alternans has been linked to ventricular fibrillation, and thus the ability to predict the onset of alternans could be clinically beneficial. Theoretically, it has been proposed that the slope of a restitution curve, ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2011.01.009
更新日期:2011-02-16 00:00:00
abstract::Thermal stability of proteins is crucial for both biotechnological and therapeutic applications. Rational protein engineering therefore frequently aims at increasing thermal stability by introducing stabilizing mutations. The accurate prediction of the thermodynamic consequences caused by mutations, however, is highly...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2010.01.051
更新日期:2010-05-19 00:00:00
abstract::A new stable substrate applicable to the observation of DNA molecules by atomic force microscopy (AFM) was fabricated from a ultrasmooth sapphire (alpha-Al2O3 single crystal) plate. The atomically ultrasmooth sapphire as obtained by high-temperature annealing has hydrophobic surfaces and could not be used for the AFM ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(98)77878-6
更新日期:1998-04-01 00:00:00
abstract::Exposure of aqueous suspensions of fragments of the purple membrane of Halobacterium halobium to electric field pulses leads to transient linear dichroism phenomena. The effects are interpreted in terms of field-induced alignments of the bacteriorhodopsin chromophore. Two observed relaxation times (tau) are attributed...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(77)85558-6
更新日期:1977-07-01 00:00:00
abstract::Mathematical models are increasingly important in biology, and testability is becoming a critical issue. One limitation is that one model simulation tests a parameter set representing one instance of the biological counterpart, whereas biological systems are heterogeneous in their properties and behavior, and a model ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2012.09.034
更新日期:2012-11-07 00:00:00