Abstract:
:We present a minimal model of plasma membrane heterogeneity that combines criticality with connectivity to cortical cytoskeleton. The development of this model was motivated by recent observations of micron-sized critical fluctuations in plasma membrane vesicles that are detached from their cortical cytoskeleton. We incorporate criticality using a conserved order parameter Ising model coupled to a simple actin cytoskeleton interacting through point-like pinning sites. Using this minimal model, we recapitulate several experimental observations of plasma membrane raft heterogeneity. Small (r ∼ 20 nm) and dynamic fluctuations at physiological temperatures arise from criticality. Including connectivity to the cortical cytoskeleton disrupts large fluctuations, prevents macroscopic phase separation at low temperatures (T ≤ 22°C), and provides a template for long-lived fluctuations at physiological temperature (T = 37°C). Cytoskeleton-stabilized fluctuations produce significant barriers to the diffusion of some membrane components in a manner that is weakly dependent on the number of pinning sites and strongly dependent on criticality. More generally, we demonstrate that critical fluctuations provide a physical mechanism for organizing and spatially segregating membrane components by providing channels for interaction over large distances.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Machta BB,Papanikolaou S,Sethna JP,Veatch SLdoi
10.1016/j.bpj.2011.02.029subject
Has Abstractpub_date
2011-04-06 00:00:00pages
1668-77issue
7eissn
0006-3495issn
1542-0086pii
S0006-3495(11)00247-5journal_volume
100pub_type
杂志文章abstract::The susceptibility of the Neurospora crassa (slime) cellular membrane to electroporation and electrodestruction in an alternating electric field was further investigated. The results were analyzed according to the dynamic rheological model of the cytoplasmic membrane. Based on an analytical description of membrane sus...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(96)79647-9
更新日期:1996-02-01 00:00:00
abstract::A simple method of generating electric field-induced concentration gradients in planar supported bilayers has been developed. Gradients of charged, fluorescently labeled probes were visualized by epifluorescence microscopy and could be observed at field strengths as low as 1 V/cm. Steady-state concentration gradients ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)80067-6
更新日期:1995-11-01 00:00:00
abstract::Galactose and other chemotactic attractants have been shown to trigger an apparent hyperpolarization in Escherichia coli (Eisenbach, M., 1982, Biochemistry, 21:6818-6825). The probe used to measure membrane potential in that study, tetraphenylphosphonium (TPP+), may respond also to surface-charge changes in the membra...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(84)84169-7
更新日期:1984-02-01 00:00:00
abstract::The functions and elasticities of the cell are largely related to the structures of the cytoskeletons underlying the lipid bilayer. Among various cell types, the red blood cell (RBC) possesses a relatively simple cytoskeletal structure. Underneath the membrane, the RBC cytoskeleton takes the form of a two-dimensional ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2015.10.036
更新日期:2015-12-01 00:00:00
abstract::Microscopic calcium (Ca2+) events (such as Ca2+ sparks) are an important area for study, as they help clarify the mechanism(s) underlying intracellular signaling. In the heart, Ca2+ sparks occur as a result of Ca2+ release from the sarcoendoplasmic reticulum, via ryanodine receptor channels. Measurement of Ca2+ spark ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.108.135251
更新日期:2008-12-15 00:00:00
abstract::The voltage-gated potassium channel protein KvLQT1 (Wang et al., 1996. Nature Genet. 12:17-23) is believed to underlie the delayed rectifier potassium current of cardiac muscle together with the small membrane protein minK (also named IsK) as an essential auxiliary subunit (Barhanin et al., 1996. Nature. 384:78-80; Sa...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(98)77568-X
更新日期:1998-08-01 00:00:00
abstract::Hundreds of cationic antimicrobial and cell-penetrating peptides (CPPs) form amphipathic α-helices when bound to lipid membranes. Here, we test two hypotheses for the differences in the ability of these peptides to translocate across membranes. The first, which we now call the hydrophobicity hypothesis, is that peptid...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2016.08.047
更新日期:2016-10-18 00:00:00
abstract::Frog skeletal muscle fibers, mechanically skinned under water-saturated silicone oil, swell upon transfer to aqueous relaxing medium (60 mM KCl; 3 mM MgCl(2); 3 mM ATP; 4 mM EGTA; 20 mM Tris maleate; pH = 7.0; ionic strength 0.15 M). Their cross-sectional areas, estimated with an elliptical approximation, increase 2.3...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(77)85573-2
更新日期:1977-08-01 00:00:00
abstract::The energy transfer and charge separation kinetics of a photosystem I (PS I) core particle of an antenna size of 100 chlorophyll/P700 has been studied by combined fluorescence and transient absorption kinetics with picosecond resolution. This is the first combined picosecond study of transient absorption and fluoresce...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(93)81552-2
更新日期:1993-06-01 00:00:00
abstract::Cofilin/ADF, beryllium fluoride complex (BeFx), and phalloidin have opposing effects on actin filament structure and dynamics. Cofilin/ADF decreases the stability of F-actin by enhancing disorder in subdomain 2, and by severing and accelerating the depolymerization of the filament. BeFx and phalloidin stabilize the su...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.087767
更新日期:2006-12-15 00:00:00
abstract::The formation and function of the mitotic spindle depends upon force generation by multiple molecular motors and by the dynamics of microtubules, but how these force-generating mechanisms relate to one another is unclear. To address this issue we have modeled the separation of spindle poles as a function of time durin...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(03)74895-4
更新日期:2003-02-01 00:00:00
abstract::A two-dimensional stochastic model for the dynamics of microtubules in gliding-assay experiments is presented here, which includes the viscous drag acting on the moving fiber and the interaction with the kinesins. For this purpose, we model kinesin as a spring, and explicitly use parameter values to characterize the m...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(01)76223-6
更新日期:2001-06-01 00:00:00
abstract::Communication-deficient cells (the SKHep1 cell line) were stably transfected with a plasmid containing cDNA which encodes the major gap junction protein of rat liver, connexin32. Application of the dual whole-cell voltage clamp technique with patch electrodes to pairs of transfected SKHep1 cells revealed strong sensit...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(91)82160-9
更新日期:1991-11-01 00:00:00
abstract::An equation is derived, which connects two functions P(r) and g(x), the first being related to the scattering intensity by a simple transformation, the second to the elctron density distribution of a spherically symmetric structure. This relation seems to be a suitable starting point for an analysis of shell structure...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(74)85910-2
更新日期:1974-03-01 00:00:00
abstract::The presence of two liquid-crystalline phases, alpha and beta, in mixed bilayers of dimyristoylphosphatidylcholine/cholesterol was detected by the changes in the distribution of the fluorescence lifetimes of t-PnA, as analyzed by the Maximum Entropy Method. The formation of the liquid-ordered beta-phase, in the 30-40 ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)80273-0
更新日期:1995-03-01 00:00:00
abstract::The effect of salt and pH titration on the selectivity of spin-labeled analogues of phosphatidic acid, phosphatidylserine, phosphatidylcholine, and stearic acid for the nicotinic acetylcholine receptor (nAcChoR) reconstituted into dioleoylphosphatidylcholine was examined at 0 degrees C using electron spin resonance sp...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(93)81422-X
更新日期:1993-03-01 00:00:00
abstract::Recent experiments suggested that cholesterol and other lipid components of high negative spontaneous curvature facilitate membrane fusion. This is taken as evidence supporting the stalk-pore model of membrane fusion in which the lipid bilayers go through intermediate structures of high curvature. How do the high-curv...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.097923
更新日期:2007-04-15 00:00:00
abstract::The fusion of a membrane-bounded vesicle with a target membrane is a key step in intracellular trafficking, exocytosis, and drug delivery. Molecular dynamics simulations have been used to study the fusion of small unilamellar vesicles composed of a dipalmitoyl-phosphatidylcholine (DPPC)/palmitic acid 1:2 mixture in at...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.103572
更新日期:2007-06-15 00:00:00
abstract::Cell-reorganized fibronectin layers on polymer films providing a gradation of the binding strength between protein and substrate were analyzed by combined fluorescence and scanning force microscopy. The nanoscale fibronectin patterns exhibited paired parallel fibrils with characteristic spacings of 156, 233, 304, and ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.048074
更新日期:2005-01-01 00:00:00
abstract::Multiple data are available on the self-assembly of mixtures of bilayer-forming amphiphiles, particularly phospholipids and micelle-forming amphiphiles, commonly denoted detergents. The structure of such mixed assemblies has been thoroughly investigated, described in phase diagrams, and theoretically rationalized in t...
journal_title:Biophysical journal
pub_type: 杂志文章,评审
doi:10.1016/j.bpj.2013.06.007
更新日期:2013-07-16 00:00:00
abstract::When cells migrate through constricting pores, they incur DNA damage and develop genomic variation. Experiments show that this damage is not due to DNA breakage from mechanical stress on chromatin in the deformed nucleus. Here we propose a model for a mechanism by which nuclear deformation can lead to DNA damage. We t...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2017.04.037
更新日期:2017-06-06 00:00:00
abstract::The elastic theory of flexural waves in thin rods accurately predicts the velocity of flagellar bending waves over a wide range of viscosities. This shows that flagella behave as a purely mechanical system for the transmission of these waves. An evaluation of the total bending moment reveals that this moment occurs in...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(71)86227-6
更新日期:1971-05-01 00:00:00
abstract::Cysteine residues introduced by site-directed mutagenesis have been used to probe the conformation and dynamics of two receptors in the E. coli chemotaxis pathway. (a) Thermal motions of the polypeptide backbone were investigated in the periplasmic D-galactose and D-glucose receptor, a globular protein of known struct...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(92)81806-4
更新日期:1992-04-01 00:00:00
abstract::The electric quadrupole moment of the deuterium nucleus provides a nuclear magnetic resonance (NMR) probe of electric field gradients, and thereby of organization of tissue water. 8-17% of H(2)O in rat muscle and brain was replaced by D(2)O from 50% deuterated drinking water. The peak height of the steady-state NMR sp...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(69)86388-5
更新日期:1969-03-01 00:00:00
abstract::The theory of the electromagnetic blood flow measuring technique is extended from the well known case (conductive liquid flowing through an insulating tube) to more realistic situations. First the conductivity of the vessel is taken into account, and the electric potentials in both liquid and vessel wall are calculate...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/s0006-3495(61)86912-9
更新日期:1961-11-01 00:00:00
abstract::The amyloid fibrillar form of the protein Tau is involved in a number of neurodegenerative diseases, also known as tauopathies. In this work, six different fibrillar Tau isoforms were assembled in vitro. The morphological and nanomechanical properties of these isoforms were studied using atomic force microscopy at hig...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2020.10.045
更新日期:2020-12-15 00:00:00
abstract::Recently a periplasmic glucose/galactose binding protein, GGRQ26C, immobilized on a gold surface has been used as an active part of a glucose biosensor based on quartz microbalance technique. However the nature of the glucose detection was not clear. Here we have found that the receptor protein film immobilized on the...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.060442
更新日期:2006-02-01 00:00:00
abstract::It has long been appreciated that spatiotemporal dynamics of cell migration are under the control of intracellular signaling pathways, which are mediated by adhesion receptors and other transducers of extracellular cues. Further, there is ample evidence that aspects of cell migration are stochastic: how else could it ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2009.09.051
更新日期:2010-01-06 00:00:00
abstract::The crowded environment of cells poses a challenge for rapid protein-protein association. Yet, it has been established that the rates of association are similar in crowded and in dilute solutions. Here we probe the pathway leading to fast association between TEM1 β-lactamase and its inhibitor protein BLIP in crowded s...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2012.08.009
更新日期:2012-09-05 00:00:00
abstract::Alamethicin is a 19-residue hydrophobic peptide, which is extended by a C-terminal phenylalaninol but lacks residues that might anchor the ends of the peptide at the lipid-water interface. Voltage-dependent ion channels formed by alamethicin depend strongly in their characteristics on chain length of the host lipid me...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.104026
更新日期:2007-06-01 00:00:00