Abstract:
:Identifying the basic module of enzymatic amplification as an irreversible cycle of messenger activation/deactivation by a "push-pull" pair of opposing enzymes, we analyze it in terms of gain, bandwidth, noise, and power consumption. The enzymatic signal transduction cascade is viewed as an information channel, the design of which is governed by the statistical properties of the input and the noise and dynamic range constraints of the output. With the example of vertebrate phototransduction cascade we demonstrate that all of the relevant engineering parameters are controlled by enzyme concentrations and, from functional considerations, derive bounds on the required protein numbers. Conversely, the ability of enzymatic networks to change their response characteristics by varying only the abundance of different enzymes illustrates how functional diversity may be built from nearly conserved molecular components.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Detwiler PB,Ramanathan S,Sengupta A,Shraiman BIdoi
10.1016/S0006-3495(00)76519-2subject
Has Abstractpub_date
2000-12-01 00:00:00pages
2801-17issue
6eissn
0006-3495issn
1542-0086pii
S0006-3495(00)76519-2journal_volume
79pub_type
杂志文章abstract::The electrical membrane potential (Vm) is one of the components of the electrochemical potential of protons across the biological membrane (proton motive force), which powers many vital cellular processes. Because Vm also plays a role in signal transduction, measuring it is of great interest. Over the years, a variety...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2019.10.030
更新日期:2020-01-07 00:00:00
abstract::For immobilized nitroxide spin-labels with a well-defined interprobe geometry, resolved dipolar splittings can be observed in continuous wave electron paramagnetic resonance (CW-EPR) spectra for interelectron distances as large as 30 A using perdeuterated probes. In this work, algorithms are developed for calculating ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(97)78832-5
更新日期:1997-04-01 00:00:00
abstract::We apply fluorescence lifetime imaging to the membrane phase-sensing dye di-4-ANEPPDHQ in model membranes and live cells. We show that the 1700 ps lifetime shift between liquid-disordered and liquid-ordered phases offers greater contrast than the 60 nm spectral shift previously reported. Detection of cholesterol-rich ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.084673
更新日期:2006-06-01 00:00:00
abstract::Using molecular dynamics simulations, we studied the mode of association of the cell-penetrating peptide penetratin with both a neutral and a charged bilayer. The results show that the initial peptide-lipid association is a fast process driven by electrostatic interactions. The homogeneous distribution of positively c...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.052787
更新日期:2005-02-01 00:00:00
abstract::The bonding rules for actin filament bundles do not lead to a particular packing symmetry, but allow for either regular or disordered filament packing. Indeed, both hexagonal and disordered types of packing are observed in vivo. To investigate factors which control bundle order, as well as size, we examined the effect...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(91)82239-1
更新日期:1991-02-01 00:00:00
abstract::The motility of Amoeba proteus was examined using the technique of passive particle tracking microrheology, with the aid of newly developed particle tracking software, a fast digital camera, and an optical microscope. We tracked large numbers of endogeneous particles in the amoebae, which displayed subdiffusive motion...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.123851
更新日期:2008-04-15 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(03)70025-3
更新日期:2003-05-01 00:00:00
abstract::We propose a general scheme for measuring the attraction between mechanically frustrated semiflexible fibers by measuring their thermal fluctuations and shape. We apply this analysis to a system of sickle hemoglobin (HbS) fibers that laterally attract one another. These fibers appear to "zip" together before reaching ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.050856
更新日期:2005-04-01 00:00:00
abstract::A major challenge in the study of biomolecular assemblies is to identify reaction coordinates that precisely monitor conformational rearrangements. This is central to the interpretation of single-molecule fluorescence resonance energy transfer measurements, where the observed dynamics depends on the labeling strategy....
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2017.10.021
更新日期:2017-12-19 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2009.12.4324
更新日期:2010-04-21 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.108.134387
更新日期:2008-11-15 00:00:00
abstract::The addition of 10(-3) M p-chloromercuribenzene sulfonate (PCMBS) to the solution bathing the mucosal surface of rabbit colon has no effect on the rate of active Na transport but blocks or reverses the inhibitory action of amiloride. The tissue must be exposed to PCMBS for 20-30 min for a complete blocking effect, and...
journal_title:Biophysical journal
pub_type: 杂志文章
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更新日期:1978-04-01 00:00:00
abstract::Paxillin is an adaptor molecule involved in the assembly of focal adhesions. Using different fluorescence fluctuation approaches, we established that paxillin-EGFP is dynamic on many timescales within the cell, ranging from milliseconds to seconds. In the cytoplasmic regions, far from adhesions, paxillin is uniformly ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.104984
更新日期:2008-04-01 00:00:00
abstract::Two independent methods, induced osmosis and solvent drag, were used to determine the reflection coefficients for NaCl (sigma NaCl) in brush border and basolateral membrane vesicles isolated from rabbit proximal tubule. In the induced osmosis method, vesicles loaded with sucrose were subjected to varying inward NaCl g...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(89)82920-0
更新日期:1989-06-01 00:00:00
abstract::A structural model is suggested for axon membranes consisting of a double layer of lipid and phospholipid molecules in which the polar ends of certain phospholipids change their orientation and combining properties under the influence of an electric field. The phosphate groups act as ion exchange "gates" for the contr...
journal_title:Biophysical journal
pub_type: 杂志文章
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更新日期:1964-05-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2020.05.017
更新日期:2020-07-07 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(96)79810-7
更新日期:1996-05-01 00:00:00
abstract::The shapes of fluorescence induction curves in spinach chloroplasts, measured using double-flash pump-probe techniques, are shown to depend on the duration of the actinic flashes. For flash durations tau(0) = 2 mus, the variable fluorescence F(nu) grows exponentially (or nearly so) with increasing fluence J of the a...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(91)82233-0
更新日期:1991-02-01 00:00:00
abstract::Fundamental mechanisms governing cell size control and homeostasis are still poorly understood. The relationship between sizes at division and birth in single cells is used as a metric to categorize the basis of size homeostasis. Cells dividing at a fixed size regardless of birth size (sizer) are expected to show a di...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2019.09.031
更新日期:2019-11-05 00:00:00
abstract::Ultrasonic relaxation of multilamellar liposomes formed from dipalmitoylphosphatidylcholine was measured near the gel-to-liquid crystal transition by a differential ultrasonic resonator. The relaxation time and strength increased remarkably near the transition temperature, indicating a pseudocritical phenomenon. A qua...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(83)84379-3
更新日期:1983-05-01 00:00:00
abstract::Solution small angle x-ray scattering can be used to study the association of transmembrane proteins solubilized in detergent micelles. We have used the alpha-helical transmembrane domain of the human erythrocyte glycophorin A (GpA) fused to the carboxyl terminus of monomeric staphylococcal nuclease (SN/GpA) as a mode...
journal_title:Biophysical journal
pub_type: 杂志文章
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journal_title:Biophysical journal
pub_type: 杂志文章
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更新日期:1995-11-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2015.06.051
更新日期:2015-08-04 00:00:00
abstract::The crystal structure of the RNA octamer, 5'-GGCGUGCC-3' has been determined from x-ray diffraction data to 1.5 angstroms resolution. In the crystal, this oligonucleotide forms five self-complementary double-helices in the asymmetric unit. Tandem 5'GU/3'UG basepairs comprise an internal loop in the middle of each dupl...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.081018
更新日期:2006-06-15 00:00:00
abstract::The intracellular and interstitial potentials associated with each cell or fiber in multicellular preparations carrying a uniformly propagating wave are important for characterizing the electrophysiological behavior of the preparation and in particular, for evaluating the source contributed by each fiber. The aforemen...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(88)83172-2
更新日期:1988-06-01 00:00:00
abstract::Nipah is an emerging paramyxovirus that is of serious concern to human health. It invades host cells using two of its membrane proteins-G and F. G binds to host ephrins and this stimulates G to activate F. Upon activation, F mediates virus-host membrane fusion. Here we focus on mechanisms that underlie the stimulation...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2016.09.002
更新日期:2016-10-18 00:00:00
abstract::The circadian clocks keeping time in many living organisms rely on self-sustained biochemical oscillations entrained by external cues, such as light, to the 24-h cycle induced by Earth's rotation. However, environmental cues are unreliable due to the variability of habitats, weather conditions, or cue-sensing mechanis...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2011.04.043
更新日期:2011-06-08 00:00:00
abstract::Thermotropic phase transitions in single planar bilayers of glycerol mono-oleate have been investigated using quasi-elastic light scattering from thermally excited membrane fluctuations. In certain cases both spectroscopic and intensity information were derived from the observations. For solvent-free bilayers transiti...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(86)83716-X
更新日期:1986-04-01 00:00:00
abstract::Synchrotron radiation circular dichroism, Fourier transform infrared, and nuclear magnetic resonance spectroscopies, and small-angle x-ray scattering were used to monitor the reversible thermal unfolding of hen egg white lysozyme. The results were compared with crystal structures and high- and low-temperature structur...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2010.07.060
更新日期:2010-10-06 00:00:00
abstract::We describe a statistical technique, the joint peristimulus time (PST) scatter diagram, for the analysis of data from simultaneously recorded neurons subjected to repeated stimulation. Distinguishable features in the scatter diagram are related to effects of the stimulus on the observed neurons and to functional relat...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(72)86097-1
更新日期:1972-05-01 00:00:00