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1

Skeleton - bilayer interaction and the shape of red blood cells

100%
Svetina S.
Cellular and Molecular Biology Letters
|
1998
|
tom 03
|
nr 4
The shapes of red blood cells with fluid interior depend on the properties of their membranes. The red blood cell membrane is composed of a bilayer, containing integral proteins, and the underlying membrane skeleton, which are attached to each other through different specific and nonspecific linkages. A short account is given of theories of shape formation based on the description of the membrane as a single- or multi-layered elastic continuum. Existing experimental evidence is then outlined which indicates that some relevant shape determining factors reside in the specific properties of different red blood cell integral and skeletal proteins. In this context a theoretical approach is introduced, based on the chemical equilibria established by the interacting skeletal and integral proteins. A simple prototype model is analyzed, taking into consideration that the binding between integral membrane proteins and the skeleton depends on membrane curvature. The essential parameters of the model are the gross value of the corresponding interaction energy and the coefficient measuring the dependence of this energy on membrane curvature. The effects of these parameters on RBC shapes and on the lateral mobility of integral membrane proteins are demonstrated.
2

Interaction of spectrin with the low molecular weight phosphotyrosine phosphatase [LMW-PTP]

88%
Lecomte M. C., Nicolas G., Fournier C., Galand C., Malbert-Colas L., Bournier O., Dhermy D., Grandchamp B.
Cellular and Molecular Biology Letters
|
2001
|
tom 06
|
nr 2
3

The membrane skeleton: mechanoprotector and mediator of mechanosensitive surface area

88%
Morris C. E.
Cellular and Molecular Biology Letters
|
2001
|
tom 06
|
nr 2
4

Red blood cell shape and deformability in the context of the functional evolution of its membrane structure

75%
Svetina S.
Cellular and Molecular Biology Letters
|
2012
|
tom 17
|
nr 2
It is proposed that it is possible to identify some of the problems that had to be solved in the course of evolution for the red blood cell (RBC) to achieve its present day effectiveness, by studying the behavior of systems featuring different, partial characteristics of its membrane. The appropriateness of the RBC volume to membrane area ratio for its circulation in the blood is interpreted on the basis of an analysis of the shape behavior of phospholipid vesicles. The role of the membrane skeleton is associated with preventing an RBC from transforming into a budded shape, which could form in its absence due to curvature-dependent transmembrane protein-membrane interaction. It is shown that, by causing the formation of echinocytes, the skeleton also acts protectively when, in vesicles with a bilayer membrane, the budded shapes would form due to increasing difference between the areas of their outer and inner layers.
5

Mechanical and functional aspects of membrane skeletons

75%
Svetina S., Bozic B., Derganc J., Zeks B.
Cellular and Molecular Biology Letters
|
2001
|
tom 06
|
nr 2
6

A role of membrane skeleton in discontinuous red blood cell shape transformations

75%
Iglic A., Svetina S., Zeks B.
Cellular and Molecular Biology Letters
|
1996
|
tom 01
|
nr 2
A possible physical interpretation of a discontinuous transition between different red blood cell shapes is given. The red blood cell membrane is considered to consist of the bilayer part and the underlaying membrane skeleton. By taking into consideration that the stable cell shape corresponds to the minimum of the membrane energy, that consists of the bilayer and skeleton elastic energies and of the bilayer-skeleton interaction energy, it is shown that aggregation of the skeleton can cause the discontinuous cell shape transformation from a shape with the bilayer completely underlaid with the skeleton to the shape involving a spherical parent cell with completely underlaid bilayer and spherical daughter vesicles without the skeleton.
7

Ankyrins, multifunctional proteins involved in many cellular pathways

75%
Hryniewicz-Jankowska A., Czogalla A., Bok E., Sikorski A. F.
Folia Histochemica et Cytobiologica
|
2002
|
tom 40
|
nr 3
8

Regulation of transmembrane signaling by the membrane skeleton in platelets

75%
Fox J. E. B.
Cellular and Molecular Biology Letters
|
1996
|
tom 01
|
nr 2
The cytoskeleton is involved in regulating motile events and properties of the plasma membrane. However, it is now clear that the cytoskeleton can bind signaling molecules, recruiting them adjacent to their substrates, and/or inducing their activation. In platelets, the membrane is lined by a skeleton which in turn associates with membrane glycoproteins. Signaling molecules associate with the membrane skeleton in unstimulated platelets and preliminary evidence suggests that components of the membrane skeleton may become phosphorylated on tyrosine residues when platelets are activated. As adhesion receptors bind their ligands, the membrane skeleton becomes more tightly associated with the underlying actin filaments and additional signaling molecules are recruited to the integrin- cytoskeletal complexes. This article describes the evidence for association of signaling molecules with the platelet cytoskeleton and discusses the potential significance of such interactions.
9

Size, shape and secondary structure of calponin

75%
Czurylo E. A., Eimer W., Kulikova N., Hellweg T.
Acta Biochimica Polonica
|
2000
|
tom 47
|
nr 3
The overall size and shape of the chicken gizzard calponin (CaP) h1 molecule was investigated by dynamic light scattering (DLS) measurements. From the DLS experiments, a z-averaged translational diffusion coefficient is derived (5.75 0.3) 10-7cm2s-1, which corresponds to a hydrodynamic radius of 3.72 nm for calponin. The frictional ratio (1.8 for the unhydrated molecule and 1.5 for the hydrated one) suggests a pronounced anisotropic structure for the molecule. An ellipsoidal model in length 19.4 nm and with a diameter of 2.6 nm used for hydrodynamic calculations was found to reproduce the DLS experimental data. The evaluation of the secondary structure of CaP h1 from the CD spectra by two independent methods has revealed that it contains, on average, 23% helix, 19% beta-strand, 18% beta-turns and loops, and 40% of remainder structures. These values are in good agreement with those predicted from the amino-acid sequence. Predictions used for CaP h1 were applied to other isoforms of known sequences and revealed that all calponins share a common secondary structure. Moreover, the predicted structure of the calponin CH domain is identical to that found by X-ray studies of the spectrin, fimbrin and utrophin CH domains.
10

Protein profiling of sickle cell versus control RBC core membrane skeletons by ICAT technology and tandem mass spectrometry

75%
Chou J., Choudhary P. K., Goodman S. R.
Cellular and Molecular Biology Letters
|
2006
|
tom 11
|
nr 3
A proteomic approach using a cleavable ICAT reagent and nano-LC ESI tandem mass spectrometry was used to perform protein profiling of core RBC membrane skeleton proteins between sickle cell patients (SS) and controls (AA), and determine the efficacy of this technology. The data was validated through Peptide/Protein Prophet and protein ratios were calculated through ASAPratio. Through an ANOVA test, it was determined that there is no significant difference in the mean ratios from control populations (AA1/AA2) and sickle cell versus control populations (AA/SS). The mean ratios were not significantly different from 1.0 in either comparison for the core skeleton proteins (α spectrin, β spectrin, band 4.1 and actin). On the natural-log scale, the variation (standard deviation) of the method was determined to be 14.1% and the variation contributed by the samples was 13.8% which together give a total variation of 19.7% in the ratios.
11

Transbilayer organization and dynamics of phospholipids in the erythrocyte membrane

75%
Roelofsen B., Op den Kamp J.A.F.
Biophysics of Membrane Transport
|
1992
|
tom 11
|
nr 2
12

Tissue-distribution of two alpha fodrin isoforms: characterization and study of their sensitivity to calpain

75%
Nicolas G., Malbert-Colas L., Gautero H., Fournier C., Lecomte M. C.
Cellular and Molecular Biology Letters
|
1998
|
tom 03
|
nr 2
13

Properties of layered membranes as the basis for membrane fusion and vesiculation processes

75%
Svetina S., Iglic A., Zeks B.
Biophysics of Membrane Transport
|
1994
|
tom 12
|
nr 2
14

Stress-free state of the red blood cell membrane and the deformation of its skeleton

63%
Svelc T., Svetina S.
Cellular and Molecular Biology Letters
|
2012
|
tom 17
|
nr 2
The response of a red blood cell (RBC) to deformation depends on its membrane, a composite of a lipid bilayer and a skeleton, which is a closed, twodimensional network of spectrin tetramers as its bonds. The deformation of the skeleton and its lateral redistribution are studied in terms of the RBC resting state for a fixed geometry of the RBC, partially aspirated into a micropipette. The geometry of the RBC skeleton in its initial state is taken to be either two concentric circles, a references biconcave shape or a sphere. It is assumed that in its initial state the skeleton is distributed laterally in a homogeneous manner with its bonds either unstressed, presenting its stress-free state, or prestressed. The lateral distribution was calculated using a variational calculation. It was assumed that the spectrin tetramer bonds exhibit a linear elasticity. The results showed a significant effect of the initial skeleton geometry on its lateral distribution in the deformed state. The proposed model is used to analyze the measurements of skeleton extension ratios by the method of applying two modes of RBC micropipette aspiration.
15
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Molecular mechanism of histamine release: the role of intermediate filaments and membrane skeletons

63%
Tasaka K.
Journal of Physiology and Pharmacology
|
1994
|
tom 45
|
nr 4
16

The role of the membrane skeleton in formation of the irreversibly sickled cell: a review

63%
Goodman S. R.
Cellular and Molecular Biology Letters
|
1996
|
tom 01
|
nr 1
In this review we discuss the evidence in support of the concept that a posttranslational modification in β-actin, in which a disulfide bridge is formed between cysteine284 and cysteine373, is the major cause of the formation of the irreversibly sickled cell (ISC). This ISC β-actin modification caused a decreased ability of the ISC membrane skeletal proteins to disassemble, as compared to the control and reversible sickled cell (RSC) membrane skeleton, because of altered actin filament formation. The slow disassembly of the ISC membrane skeleton proteins gives a reasonable explanation for the inability of the ISC to remodel its shape. An understanding of the molecular basis of the irreversibly sickled cells formation has helped initiate a rationale for development of drugs to block ISC formation in vivo.
17

Interaction of spectrin with phospholipids is inhibited by isolated erythrocyte ankyrin. A monolayer study

63%
Bialkowska K., Lesniewski J., Nietubyc M., Sikorski A. F.
Cellular and Molecular Biology Letters
|
1999
|
tom 04
|
nr 2
It was previously found (Białkowska, K., Zembroń, A. and Sikorski, A. F. (1994) Biochim. Biophys. Acta 1191, 21-26.) that isolated erythrocyte ankyrin inhibited interaction of spectrin with phospholipid liposomes, mainly those prepared from lipid mixtures containing aminophospholipids. In this communication we report on the effect of isolated ankyrin on red blood cell spectrin interaction with phospholipids in monolayers. Our data indicate that spectrin interaction with monolayers containing PE and, to a smaller extent, PS is sensitive to inhibition by ankyrin while interaction with monolayers containing only PC is not. Tetrameric spectrin affects monolayer surface pressure similarly to the heterodimer. However, an interaction of tetrameric spectrin with phospholipids was much more effectively inhibited by purified ankyrin indicating that one site per spectrin tetramer engaged in this interaction. When interactions of purified individual spectrin subunits (α or β) with phospholipid monolayers was studied, the β-subunit caused a strong, saturable effect on the surface pressure of the PE/PC monolayer, in contrast to the α-chain which induced much smaller and monotonic changes on the surface pressure of the same monolayer. Also interactions of the β-subunit with amino-phospholipids/PC monolayers were more sensitive to inhibition by ankyrin than those with native αβ-heterodimer of spectrin, e.g. threefold lower concentration of ankyrin was necessary to induce the same effect, while interaction of the α-subunit with phospholipid monolayers was entirely insensitive to ankyrin. Phosphorylation of spectrin in vitro with either cAMP-dependent protein kinase, or metabolically in intact cells, induced a decrease in the effect of either dimer or tetramer on the surface pressure of phospholipid monolayers. The sensitivity of this interaction to ankyrin was also greatly diminished. When isolated ankyrin was phosphorylated by the same cAMP-dependent protein kinase its ability to compete with phospholipid for spectrin was also diminished. The described effects may indicate a physiological significance of spectrin’s interaction with phospholipids, particularly in situations when there is not enough functional ankyrin to accommodate all spectrin molecules in the membrane.
18

Erythrocytes vesiculate at high pH

63%
Bobrowska-Hagerstrand M., Iglic A., Hagerstrand H.
Cellular and Molecular Biology Letters
|
1997
|
tom 02
|
nr 1
Human erythrocytes were incubated at alkaline pH. In samples equilibrating within 60 min to pH 11 erythrocytes underwent prelytic vesiculation (fragmentation). Erythrocytes developed large (diameter often 1-2 µm) hemoglobin-filled blebs which could be released to the outer medium as hemoglobin containing vesicles. It is suggested that the described vesiculation at high pH occurs due to an uncoupling of the membrane skeleton from the lipid bilayer. Due to the uncoupling from the skeleton the erythrocyte lipid bilayer may behave similar to the membrane of a giant lipid vesicle.
19

Interaction of membrane skeletal proteins with membrane lipid domain

63%
Sikorski A. F., Hanus-Lorenz B., Jezierski A., Dluzewski A. R.
Acta Biochimica Polonica
|
2000
|
tom 47
|
nr 3
The object of this paper is to review briefly the studies on the interaction of red blood cell membrane skeletal proteins and their non-erythroid analogues with lipids in model systems as well as in natural membranes. An important question to be addressed is the physiological significance and possible regulatory molecular mechanisms in which these interactions are engaged.
20

Expression of human membrane skeleton protein genes for protein 4.1 and betaIIsigma2-spectrin assayed by real-time RT-PCR

63%
Taylor-Harris P. M., Felkin L. E., Birks E. J., Franklin R. C. G., Yacoub M. H., Baines A. J., Barton P. J. R., Pinder J. C.
Cellular and Molecular Biology Letters
|
2005
|
tom 10
|
nr 1
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