Phosphatidylserine (PS) Externalization Facilitates Membrane Vesiculation through Decreasing Membrane Stiffness

RBC agglutination by lectins represents an interactive balance between the attractive (bridging) force due to lectin binding on cell surfaces and disaggregating forces, such as membrane stiffness and electrostatic charge repulsion (1). During agglutination, critical geometric parameters of cell contour and intercellular distance reflect the magnitude of these interactive forces and the size of the bridging macromolecule (2). Valid ultrastructural measurements of these geometric parameters from agglutinated RBC's require preservation with minimal cell distortion. As chemical fixation may adversely influence RBC geometric properties (3), we used chemical fixation and cryofixation (rapid freezing followed by freeze-substitution) as a comparative approach to examine these parameters from RBC agglutinated with Ulex I lectin.

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Erythrocyte membrane vesiculation: Model for the molecular mechanism of protein sorting

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.94.24.12969 ◽

1997 ◽

Vol 94 (24) ◽

pp. 12969-12974 ◽

Cited By ~ 66

Author(s):

D. W. Knowles ◽

L. Tilley ◽

N. Mohandas ◽

J. A. Chasis

Keyword(s):

Molecular Mechanism ◽

Erythrocyte Membrane ◽

Protein Sorting ◽

Membrane Vesiculation

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Outer membrane vesiculation of acinetobacter calcoaceticus

Acta Biotechnologica ◽

10.1002/abio.370100204 ◽

1990 ◽

Vol 10 (2) ◽

pp. 117-123 ◽

Cited By ~ 6

Author(s):

P. Borneleit ◽

H.-P. Kleber ◽

H. Binder

Keyword(s):

Outer Membrane ◽

Acinetobacter Calcoaceticus ◽

Membrane Vesiculation

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Increase Membrane Vesiculation in Essential Hypertension

Laboratory Medicine ◽

10.1309/lm0aks1zxdr1uayw ◽

2012 ◽

Vol 43 (1) ◽

pp. 6-9 ◽

Cited By ~ 1

Author(s):

Duangdao Nantakomol ◽

Mallika Imwong ◽

Sumana Mas-Oodi ◽

Chotiros D. Plabplueng ◽

Chartchalerm Isarankura-Na-Ayudhya ◽

...

Keyword(s):

Essential Hypertension ◽

Membrane Vesiculation

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Erythrocyte deformation in shear flow: influences of internal viscosity, membrane stiffness, and hematocrit

Blood ◽

10.1182/blood.v69.3.727.bloodjournal693727 ◽

1987 ◽

Vol 69 (3) ◽

pp. 727-734 ◽

Cited By ~ 1

Author(s):

K Kon ◽

N Maeda ◽

T Shiga

Keyword(s):

Viscoelastic Properties ◽

Shear Force ◽

Flow Lines ◽

Extracellular Medium ◽

Intact Cells ◽

Suspension Viscosity ◽

Applied Shear Stress ◽

Erythrocyte Deformation ◽

Membrane Stiffness ◽

Internal Viscosity

The effect of shear force (depending on shear rate and viscosity of extracellular medium) and hematocrit of RBC suspension on RBC deformation was studied quantitatively using a cone-plate rheoscope with various kinds of cells, ie, partially hemolyzed (PH) cells, density-fractionated intact cells, and diamide-treated cells. The deformation index (DI) of ellipsoidally deformed cells was shown to be a function of beta gamma eta ex(eta ex/eta in)alpha, where gamma eta ex is applied shear stress, eta ex and eta in are external and internal viscosities, respectively, and alpha and beta are adjustable parameters related to the membrane viscoelastic properties. The increase of suspension viscosity at higher hematocrits (Hts) generally enhanced the ellipsoidal deformation of cells, in the same manner as increasing the suspending medium viscosity of a diluted cell suspension. The suppressing effect on cell deformation appeared above a certain Ht. When intact cells were mixed with glutaraldehyde-treated, hardened cells, the ellipsoidal deformation of intact cells was disturbed. The suppression of deformation probably occurred through disturbance of laminar flow-lines around intact cells.

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3D Tissue elongation via ECM stiffness-cued junctional remodeling

10.1101/384958 ◽

2018 ◽

Author(s):

Dong-Yuan Chen ◽

Justin Crest ◽

Sebastian J. Streichan ◽

David Bilder

Keyword(s):

Basement Membrane ◽

Cell Shape ◽

Cell Dynamics ◽

Src Tyrosine Kinase ◽

Average Cell ◽

Cellular Behavior ◽

Cell Behaviors ◽

Oriented Cell Division ◽

Morphometric Analyses ◽

Membrane Stiffness

ABSTRACTOrgans are sculpted by extracellular as well as cell-intrinsic forces, but how collective cell dynamics are orchestrated in response to microenvironmental cues is poorly understood. Here we apply advanced image analysis to reveal ECM-responsive cell behaviors that drive elongation of the Drosophila follicle, a model 3D system in which basement membrane stiffness instructs tissue morphogenesis. Through in toto morphometric analyses of WT and ‘round egg’ mutants, we find that neither changes in average cell shape nor oriented cell division are required for appropriate organ shape. Instead, a major element is a reorientation of elongated cells at the follicle anterior. Polarized reorientation is regulated by mechanical cues from the basement membrane, which are transduced by the Src tyrosine kinase to alter junctional E-cadherin trafficking. This mechanosensitive cellular behavior represents a conserved mechanism that can elongate ‘edgeless’ tubular epithelia in a process distinct from those that elongate bounded, planar epithelia.

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The Effect of Proteins and Lipids on Membrane Stiffness

Biophysical Journal ◽

10.1016/j.bpj.2015.11.1338 ◽

2016 ◽

Vol 110 (3) ◽

pp. 243a

Author(s):

Philip W. Fowler ◽

Anna Duncan ◽

Jean Helie ◽

Matthieu Chavent ◽

Heidi Koldsø ◽

...

Keyword(s):

Membrane Stiffness

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Characterization of the complement sensitivity of calcium loaded human erythrocytes

Blood ◽

10.1182/blood.v78.11.3056.3056 ◽

1991 ◽

Vol 78 (11) ◽

pp. 3056-3065 ◽

Cited By ~ 17

Author(s):

ST Test ◽

P Butikofer ◽

MC Yee ◽

FA Kuypers ◽

B Lubin

Keyword(s):

Red Blood Cells ◽

Blood Cells ◽

Paroxysmal Nocturnal Hemoglobinuria ◽

Recent Observation ◽

Membrane Vesicles ◽

Intracellular Potassium ◽

Calcium Loading ◽

Increased Sensitivity ◽

Membrane Vesiculation

Abstract A deficiency of membrane proteins having a glycosylphosphatidylinositol (GPI) anchor is characteristic of the erythrocytes of paroxysmal nocturnal hemoglobinuria (PNH) and is currently believed to be the basis for the enhanced susceptibility to lysis by activated complement observed in these cells. Our recent observation that GPI-anchored proteins are preferentially lost into membrane vesicles shed from normal erythrocytes after calcium loading led us to examine the hypothesis that the remnant erythrocytes might also have increased sensitivity to complement-mediated hemolysis. Indeed, red blood cells treated in such a manner became more sensitive to lysis by antibody and complement or to lysis initiated by activated cobra venom factor complexes (CoFBb). As a consequence of membrane vesiculation, the erythrocytes lost up to approximately 50% of their immunoreactive decay- accelerating factor and 25% to 30% of their immunoreactive membrane inhibitor of reactive lysis (MIRL). Closer examination of the defect responsible for the marked increase in sensitivity to CoFBb-initiated hemolysis seen in calcium-loaded erythrocytes showed that a complex combination of factors produced the defect. These included a decrease in both functional and immunoreactive MIRL and depletion of intracellular potassium and adenosine triphosphate (ATP). These results suggest the possibility that loss of DAF and MIRL via membrane vesiculation, as well as decreases in intracellular potassium and/or ATP, might contribute to the phenotype of PNH erythrocytes. Further, normal or pathologic red blood cells might develop a PNH-like defect after membrane vesiculation if sufficient decreases in potassium and ATP also occurred.

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