Surface redistribution and release of antibody-induced caps in entamoebae.

Polyspecific antibodies bound to Entamoeba induced surface redistribution of membrane components toward the uroid region. Capping of surface antigens was obtained with a single layer of antibodies in E. histolytica and E. invadens. This surface segregation progressed to a large accumulation of folded plasma membrane that extruded as a defined vesicular cap. A spontaneous release of the cap at the end of the capping process took place. These released caps contained most of the antibodies that originally bound to the whole cell surface. Two-thirds of radiolabeled antibodies bound to the surface of E. histolytica were released into the medium in 2 h. Successive capping induced by repeated exposure of E. invadens to antibodies produced conglomerates of folded surface membrane, visualized as stacked caps, in proportion to the number of antibody exposures. These results indicate the remarkable ability of Entamoeba to rapidly regenerate substantial amounts of plasma membbrane. The properties of surface redistribution, liberation of caps, and plasma membrane regeneration, may contribute to the survival of the parasite in the host during infection.

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The organization of cell surface membrane domains

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100155992 ◽

1989 ◽

Vol 47 ◽

pp. 804-805

Author(s):

Michael Edidin

Keyword(s):

Cell Surface ◽

Membrane Lipids ◽

Surface Membrane ◽

Lateral Diffusion ◽

Cell Types ◽

Membrane Domains ◽

Membrane Biology ◽

Morphological Polarity ◽

Discrete Domains ◽

Membrane Components

Cell surface membranes are based on a fluid lipid bilayer and models of the membranes' organization have emphasised the possibilities for lateral motion of membrane lipids and proteins within the bilayer. Two recent trends in cell and membrane biology make us consider ways in which membrane organization works against its inherent fluidity, localizing both lipids and proteins into discrete domains. There is evidence for such domains, even in cells without obvious morphological polarity and organization [Table 1]. Cells that are morphologically polarised, for example epithelial cells, raise the issue of membrane domains in an accute form.The technique of fluorescence photobleaching and recovery, FPR, was developed to measure lateral diffusion of membrane components. It has also proven to be a powerful tool for the analysis of constraints to lateral mobility. FPR resolves several sorts of membrane domains, all on the micrometer scale, in several different cell types.

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Alterations in cell surface membrane components of adapting rat small intestinal epithelium

Gastroenterology ◽

10.1016/0016-5085(78)90077-x ◽

1978 ◽

Vol 75 (6) ◽

pp. 1066-1072 ◽

Cited By ~ 21

Author(s):

Hugh J. Freeman ◽

Marilynn E. Etzler ◽

Arthur B. Garrido ◽

Young S. Kim

Keyword(s):

Cell Surface ◽

Intestinal Epithelium ◽

Surface Membrane ◽

Small Intestinal Epithelium ◽

Cell Surface Membrane ◽

Small Intestinal ◽

Membrane Components

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Membrane structure and surface coat of Entamoeba histolytica. Topochemistry and dynamics of the cell surface: cap formation and microexudate.

The Journal of Cell Biology ◽

10.1083/jcb.64.3.538 ◽

1975 ◽

Vol 64 (3) ◽

pp. 538-550 ◽

Cited By ~ 60

Author(s):

P P Silva ◽

A Martínez-Palomo ◽

A Gonzalez-Robles

Keyword(s):

Plasma Membrane ◽

Cell Surface ◽

Binding Sites ◽

Membrane Structure ◽

Ruthenium Red ◽

Iron Binding ◽

Con A ◽

Colloidal Iron ◽

Acidic Sites ◽

Membrane Components

Treatment of living entamoeba histolytica cells with low concentrations of concanavalin A (con A) and peroxidase results in redistribution of the plasma membrane con A receptors to one pole of the cell where a morphologically distinct region--the uroid--is formed. Capping of con A receptors is not accompanied by parallel accumulation of ruthenium red-stainable components. In capped cells, the pattern of distribution of acidic sites ionized at pH 1.8 (labeled by colloidal iron) at the outer surface and of membrane particles (integral membrane components revealed by freeze-fracture) is not altered over the uroid region. Cytochemistry of substrate-attached microexudate located in regions adjacent to E. histolytica cells demonstrates the presence of con A binding sites and ruthenium red- and alcian blue-stainable components and the absent of colloidal iron binding sites. In a previous report we demonstrated that glycerol-induced aggregation of the plasma membrane particles is accompanied by a discontinuous distribution of colloidal iron binding sites, while con A receptors and acidic sites ionized at pH 4.0 remain uniformly distributed over the cell surface. Taken together, our experiments show that, in E. histolytica cells, peripheral membrane components may move independently of integral components and, also, that certain surface determinants may redistribute independently of others. These results point to the complexity of the membrane structure-cell surface relationship in E. histolytica plasma membranes relative to the membrane of the erythrocyte ghost where integral components (the membrane-intercalated particles) contain all antigens, receptors, and anionic sites labeled so far. We conclude that fluidity of integral membrane components (integral membrane fluidity) cannot be inferred from the demonstration of the mobility of surface components nor, conversely, can the fluidity of peripheral membrane components (peripheral membrane fluidity) be assumed from demonstration of the mobility of integral membrane components.

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Repairing a torn cell surface: make way, lysosomes to the rescue

Journal of Cell Science ◽

10.1242/jcs.115.5.873 ◽

2002 ◽

Vol 115 (5) ◽

pp. 873-879 ◽

Cited By ~ 5

Author(s):

Paul L. McNeil

Keyword(s):

Plasma Membrane ◽

Cell Surface ◽

Actin Polymerization ◽

Surface Membrane ◽

Cell Cortex ◽

Yolk Granule ◽

Protein Markers ◽

Filamentous Actin ◽

Animal Cells ◽

Fusion Plasma

Biological membranes are often described as `self-sealing' structures. If indeed membranes do have an inherent capacity for repair, does this explain how a cell can rapidly reseal a very large (1-1000 μm2)disruption in its plasma membrane? It is becoming increasingly clear that, in nucleated animal cells, the cytoplasm plays an active and essential role in resealing. A rapid and apparently chaotic membrane fusion response is initiated locally in the cytoplasm by the Ca2+ that floods in through a disruption: cytoplasmic vesicles are thereby joined with one another(homotypically) and with the surrounding plasma membrane (exocytotically). As a consequence, internal membrane is added to cell surface membrane at the disruption site. In the case of large disruptions, this addition is hypothesized to function as a `patch'. In sea urchin eggs, the internal compartment used is the yolk granule. Several recent studies have significantly advanced our understanding of how cells survive disruption-inducing injuries. In fibroblasts, the lysosome has been identified as a key organelle in resealing. Protein markers of the lysosome membrane appear on the surface of fibroblasts at sites of disruption. Antibodies against lysosome-specific proteins, introduced into the living fibroblast,inhibit its resealing response. In gastric eptithelial cells, local depolymerization of filamentous actin has been identified as a crucial step in resealing: it may function to remove a barrier to lysosome-plasma membrane contact leading to exocytotic fusion. Plasma membrane disruption in epithelial cells induces depolymerization of cortical filamentous actin and, if this depolymerization response is inhibited, resealing is blocked. In the Xenopus egg, the cortical cytoskeleton has been identified as an active participant in post-resealing repair of disruption-related damage to underlying cell cortex. A striking, highly localized actin polymerization response is observable around the margin of cortical defects. A myosin powered contraction occurring within this newly formed zone of F-actin then drives closure of the defect in a purse-string fashion.

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Genetic dissection of early endosomal recycling highlights a TORC1-independent role for Rag GTPases

The Journal of Cell Biology ◽

10.1083/jcb.201702177 ◽

2017 ◽

Vol 216 (10) ◽

pp. 3275-3290 ◽

Cited By ~ 14

Author(s):

Chris MacDonald ◽

Robert C. Piper

Keyword(s):

Plasma Membrane ◽

Cell Surface ◽

Surface Membrane ◽

Physiological Role ◽

Amino Acid Transporters ◽

Genetic Dissection ◽

Cellular Processes ◽

Rag Gtpases ◽

Endosomal Recycling ◽

Recycling Pathway

Endocytosed cell surface membrane proteins rely on recycling pathways for their return to the plasma membrane. Although endosome-to-plasma membrane recycling is critical for many cellular processes, much of the required machinery is unknown. We discovered that yeast has a recycling route from endosomes to the cell surface that functions efficiently after inactivation of the sec7-1 allele of Sec7, which controls transit through the Golgi. A genetic screen based on an engineered synthetic reporter that exclusively follows this pathway revealed that recycling was subject to metabolic control through the Rag GTPases Gtr1 and Gtr2, which work downstream of the exchange factor Vam6. Gtr1 and Gtr2 control the recycling pathway independently of TORC1 regulation through the Gtr1 interactor Ltv1. We further show that the early-endosome recycling route and its control though the Vam6>Gtr1/Gtr2>Ltv1 pathway plays a physiological role in regulating the abundance of amino acid transporters at the cell surface.

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Malaria circumsporozoite protein binds to heparan sulfate proteoglycans associated with the surface membrane of hepatocytes.

Journal of Experimental Medicine ◽

10.1084/jem.177.5.1287 ◽

1993 ◽

Vol 177 (5) ◽

pp. 1287-1298 ◽

Cited By ~ 219

Author(s):

U Frevert ◽

P Sinnis ◽

C Cerami ◽

W Shreffler ◽

B Takacs ◽

...

Keyword(s):

Molecular Weight ◽

Plasma Membrane ◽

Cell Surface ◽

Heparan Sulfate ◽

Target Cell ◽

Surface Membrane ◽

Heparan Sulfate Proteoglycans ◽

Circumsporozoite Protein ◽

Cell Specificity ◽

Region Ii

During feeding by infected mosquitoes, malaria sporozoites are injected into the host's bloodstream and enter hepatocytes within minutes. The remarkable target cell specificity of this parasite may be explained by the presence of receptors for the region II-plus of the circumsporozoite protein (CS) on the basolateral domain of the plasma membrane of hepatocytes. We have now identified these receptors as heparan sulfate proteoglycans (HSPG). The binding of CS to the receptors is abolished by heparitinase treatment, indicating that the recognition of region II-plus is via the glycosaminoglycan chains. We have purified and partially characterized the CS-binding HSPGs from HepG2 cells. They have a molecular weight of 400,000-700,000, are tightly associated with the plasma membrane, and are released from the cell surface by very mild trypsinization, a property which the CS receptors share with the syndecan family of proteoglycans.

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Identification of detergent-resistant plasma membrane microdomains in dictyostelium: enrichment of signal transduction proteins.

Molecular Biology of the Cell ◽

10.1091/mbc.8.5.855 ◽

1997 ◽

Vol 8 (5) ◽

pp. 855-869 ◽

Cited By ~ 31

Author(s):

Z Xiao ◽

P N Devreotes

Keyword(s):

Plasma Membrane ◽

Membrane Proteins ◽

Cell Surface ◽

G Protein ◽

Biochemical Characterization ◽

Surface Membrane ◽

Actin Binding ◽

Membrane Microdomains ◽

Immunogold Electron Microscopy ◽

Membrane Structures

Unlike most other cellular proteins, the chemoattractant receptor, cAR1, of Dictyostelium is resistant to extraction by the zwitterionic detergent, CHAPS. We exploited this property to isolate a subcellular fraction highly enriched in cAR1 by flotation of CHAPS lysates of cells in sucrose density gradients. Immunogold electron microscopy studies revealed a homogeneous preparation of membrane bilayer sheets. This preparation, designated CHAPS-insoluble floating fraction (CHIEF), also contained a defined set of 20 other proteins and a single uncharged lipid. Cell surface biotinylation and preembedding immunoelectron microscopy both confirmed the plasma membrane origin of this preparation. The cell surface phosphodiesterase (PDE) and a downstream effector of cAR1, adenylate cyclase (ACA), were specifically localized in these structures, whereas the cell adhesion molecule gp80, most of the major cell surface membrane proteins, cytoskeletal components, the actin-binding integral membrane protein ponticulin, and G-protein alpha- and beta-subunits were absent. Overall, CHIFF represents about 3-5% of cell externally exposed membrane proteins. All of these results indicate that CHIFF is derived from specialized microdomains of the plasma membrane. The method of isolation is analogous to that of caveolae. However, we were unable to detect distinct caveolae-like structures on the cell surface associated with cAR1, which showed a diffuse staining profile. The discovery of CHIFF facilitates the purification of cAR1 and related signaling proteins and the biochemical characterization of receptor-mediated processes such as G-protein activation and desensitization. It also has important implications for the "fluid mosaic" model of the plasma membrane structures.

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Role of cell-surface carbohydrates and plasma membrane components in the internalization of cell-penetrating peptides

Drug Discovery Today ◽

10.1016/j.drudis.2010.09.406 ◽

2010 ◽

Vol 15 (23-24) ◽

pp. 1101-1101

Author(s):

Chérine Bechara ◽

Chen-Yu Jiao ◽

Fabienne Burlina ◽

Isabel D. Alves ◽

Gérard Chassaing ◽

...

Keyword(s):

Plasma Membrane ◽

Cell Surface ◽

Cell Penetrating Peptides ◽

Cell Penetrating ◽

Membrane Components ◽

Surface Carbohydrates

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Rectilinear particle arrays in freeze-fracture replicas of the surface membrane of Paramecium tetraurelia

Journal of Cell Science ◽

10.1242/jcs.83.1.269 ◽

1986 ◽

Vol 83 (1) ◽

pp. 269-291

Author(s):

R.R. Preston ◽

T.M. Newman

Keyword(s):

Plasma Membrane ◽

Cell Surface ◽

Surface Membrane ◽

Freeze Fracture ◽

Dorsal Surface ◽

Surface Coat ◽

Paramecium Tetraurelia ◽

Intramembranous Particle ◽

Logarithmic Growth Phase ◽

Culture Cycle

Freeze-fracture replicas of the plasma membrane of unfixed, uncryoprotected Paramecium tetraurelia bear large rectilinear arrays of 11 nm particles arranged in 7–11 parallel rows. The arrays are of sufficient size to leave impressions in replicas of the underlying outer alveolar membrane, and are apparent as parallel ridges in replicas of the surface coat of deep-etched cells. By noting the location of arrays in replicas of identified portions of the cortex of P. tetraurelia, it has been possible to map the distribution of arrays over the cell surface. The arrays are found primarily over the anterior surfaces of the cell, covering an area that extends from the preoral suture over the left adoral field and a large portion of the anterior dorsal surface. Freeze-fracture analyses of cells taken from a number of different stages of a culture cycle suggest that the particle arrays are not replicated as an integral part of the cortex during cell division, but are assembled and oriented in the membrane as the cells mature. The appearance of small intramembranous particle complexes in the plasma membrane of cells in logarithmic growth phase supports this hypothesis, possibly representing an assembly stage in the formation of the larger particle arrays. The facts that the particle arrays are apparent in replicas of the surface coat of cells, are found primarily at the anterior of the cell body, and have a highly specific orientation with respect to the cell surface, strongly suggest that they function as chemoreceptors in P. tetraurelia.

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