scholarly journals Membrane flow during pinocytosis. A stereologic analysis.

1976 ◽  
Vol 68 (3) ◽  
pp. 665-687 ◽  
Author(s):  
R M Steinman ◽  
S E Brodie ◽  
Z A Cohn
Keyword(s):  
Cell Surface ◽  
Surface Area ◽  
Surface Membrane ◽  
Membrane Flow ◽  
Rapid Reduction ◽  
Secondary Lysosome ◽  
L Cells ◽  
Secondary Lysosomes ◽  
Membrane Components ◽  
Pinocytic Vesicles

HRP has been used as a cytochemical marker for a sterelogic analysis of pinocytic vesicles and secondary lysosomes in cultivated macrophages and L cells. Evidence is presented that the diaminobenzidine technique (a) detects all vaculoes containing encyme and (b) distinguishes between incoming pinocytic vesicles and those which have fused with pre-existing lysosomes to form secondary lososomes. The HRP reactive pinocytic vesicle spaces fills completely within 5 min after exposure to enzyme, while the secondary lysosome compartment is saturated in 45--60 min. The size distribution of sectioned (profile) vaculoe diameters was measured at equilibrium and converted to actual (spherical) dimensions using a technique modified from Dr. S. D. Wicksell. The most important findings in this study have to do with the rate at which pinocytosed fluid and surface membrane move into the cell and on their subsequent fate. Each minute macrophages form at least 125 pinocytic vesicles having a fractional vol of 0.43% of the cell's volume and a fractional area of 3.1% of the cell's surface area. The fractional volume and surface area flux rates for L cells were 0.05% and 0.8% per minute respectively. Macrophages and L cells thus interiorize the equivalent of their cell surface area every 33 and 125 min. During a 3-period, the size of the secondary lysosome compartment remains constant and represents 2.5% of the cell volume and 18% of the surface area. Each hour, therefore, the volume and surface area of incoming vesicles is 10 times greater than the dimensions of the secondary lysosomes in both macrophages and L cells. This implies a rapid reduction in vesicle size during the formation of the secondary lysosome and the egress of pinocytosed fluid from the vacuole and the cell. In addition, we postulate that membrane components of the vacuole are subsequently recycled back to the cell surface.

The organization of cell surface membrane domains

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.

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

1978 ◽  
Vol 75 (6) ◽  
pp. 1066-1072 ◽  
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

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

1980 ◽  
Vol 151 (1) ◽  
pp. 184-193 ◽  
Author(s):  
J Calderón ◽  
M de Lourdes Muñoz ◽  
H M Acosta
Keyword(s):  
Plasma Membrane ◽  
Cell Surface ◽  
Surface Segregation ◽  
Surface Membrane ◽  
Single Layer ◽  
Surface Antigens ◽  
Spontaneous Release ◽  
Plasma Membrane Regeneration ◽  
Membrane Components ◽  
Radiolabeled Antibodies

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.

scholarly journals Membrane flow during nematode spermiogenesis.

1982 ◽  
Vol 92 (1) ◽  
pp. 113-120 ◽  
Author(s):  
T M Roberts ◽  
S Ward
Keyword(s):  
Caenorhabditis Elegans ◽  
Diffusion Coefficients ◽  
Surface Membrane ◽  
Lateral Diffusion ◽  
Bulk Flow ◽  
Membrane Glycoproteins ◽  
Membrane Flow ◽  
Latex Beads ◽  
Membrane Components

Two distinct types of surface membrane rearrangement occur during the differentiation of Caenorhabditis elegans spermatids into amoeboid spermatozoa. The first, detected by the behavior of latex beads attached to the surface, is a nondirected, intermittent movement of discrete portions of the membrane. This movement starts when spermatids are stimulated to differentiate and stops when a pseudopod is formed. The second type of movement is a directed, continual flow of membrane components from the tip of the pseudopod to its base. Both membrane glycoproteins and fluorescent phospholipids inserted in the membrane flow backward at the same rate, approximately 4 micrometers/min, although their lateral diffusion coefficients in the membrane differ by at least a factor of 5. These observations suggest that pseudopodial membrane movement is due to bulk flow of membrane components away from the tip of the pseudopod.

A ‘Dynamic Adder Model’ For Cell Size Homeostasis in Dictyostelium Cells

2021 ◽  
Author(s):  
Masahito Tanaka ◽  
Shigehiko Yumura
Keyword(s):  
Cell Surface ◽  
Surface Area ◽  
Cell Size ◽  
Surface Membrane ◽  
Total Cell ◽  
Membrane Turnover ◽  
Cell Surface Area ◽  
Daughter Cells ◽  
A Cell ◽  
Original Size

Abstract After a cell divides into two daughter cells, the total cell surface area of the daughtercells should increase to the original size to maintain cell size homeostasis in a single cellcycle. Previously, three models have been proposed to explain the regulation of cell sizehomeostasis: sizer, timer, and adder models. Here, we precisely measured the total cellsurface area of Dictyostelium cells in a whole cell cycle by using the agar-overlaymethod, which eliminated the influence of surface membrane reservoirs, such asmicrovilli and membrane winkles. The total cell surface area linearly increased duringinterphase, slightly decreased at the metaphase, and then increased by approximately20% during cytokinesis. From the analysis of the added surface area, we concluded thatthe cell size was regulated by the near-adder model in interphase and by the timer modelin the mitotic phase. The adder model in the interphase is not caused by a simple cellmembrane addition, but is more dynamic due to the rapid cell membrane turnover. Wepropose a ‘dynamic adder model’ to explain cell size homeostasis in the interphase.

scholarly journals The membrane proteins of the vacuolar system. II. Bidirectional flow between secondary lysosomes and plasma membrane.

1980 ◽  
Vol 86 (1) ◽  
pp. 304-314 ◽  
Author(s):  
W A Muller ◽  
R M Steinman ◽  
Z A Cohn
Keyword(s):  
Plasma Membrane ◽  
Culture Medium ◽  
Fluid Phase ◽  
Membrane Flow ◽  
Em Autoradiography ◽  
Secondary Lysosomes ◽  
Bidirectional Flow ◽  
Vacuolar System ◽  
Representative Samples ◽  
Pinocytic Vesicles

Lactoperoxidase covalently coupled to latex spheres (LPO-latex) has been used to selectively iodinate the phagolysome (PL) membrane within living macrophages, as discussed in the accompanying article. This procedure labeled approximately 24 polypeptides in the PL membrane; these were similar to those iodinatable on the external surface of the plasma membrane (PM). We now report on the translocation and fate of these proteins when the cells are returned to culture. TCA-precipitable radioactivity was lost from cells with biphasic kinetics. 20-50% of the cell-associated radiolabel was rapidly digested (t 1/2 approximately equal to 1 h) and recovered in the culture medium as monoiodotyrosine. 50-80% of the label was lost slowly from cells ( 1/2 approximately equal to 24-30 h). Quantitative analysis of gel autoradiograms showed that all radiolabeled proteins were lost at the same rate in both the rapid and slow phases of digestion. Within 15-30 min aftr labeling of the PL membrane, EM autoradiography revealed that the majority of the cell-associated grains, which at time 0 were associated with PL, were now randomly dispersed over the plasmalemma. At this time, analysis of PM captured by a second phagocytic load revealed the presence of all labeled species originally present in the PL membrane. This demonstrated the rapid, synchronous centrifugal flow of PL polypeptides to the cell surface. Evidence was also obtained for the continuous influx of representative samples of the PM into the PL compartment by way of pinocytic vesicles. This was based on the constant flow of fluid phase markers into latex-containing PL and on the internalization of all iodinatable PM polypeptides into this locus. These observations provide evidence for the continuous, bidirectional flow of membrane polypeptides between the PM and the secondary lysosome and represent an example of a membrane flow and recycling mechanism.

scholarly journals Disappearance of macrophage surface folds after antibody-dependent phagocytosis.

1981 ◽  
Vol 89 (2) ◽  
pp. 223-229 ◽  
Author(s):  
H R Petty ◽  
D G Hafeman ◽  
H M McConnell
Keyword(s):  
Electron Microscopy ◽  
Cell Surface ◽  
Guinea Pig ◽  
Surface Area ◽  
Surface Membrane ◽  
Peritoneal Macrophages ◽  
Injection Technique ◽  
Surface Areas ◽  
Transmission Electron ◽  
Uptake Data

We have employed the method of Burwen and Satir (J. Cell Biol., 1977, 74:690) to measure the disappearance of surface folds from resident guinea pig peritoneal macrophages after antibody-dependent phagocytosis. Unilamellar phospholipid vesicles containing dimyristoylphosphatidylcholine and 1 mol % dinitrophenyl-epsilon-aminocaproyl-phosphatidylethanolamine, a lipid that possesses a hapten headgroup, were prepared by an ether injection technique. These vesicles were taken up by macrophages in a time- and temperature-dependent fashion. Vesicles that contained ferritin trapped in the internal aqueous volume were identified within macrophages by transmission electron microscopy. Scanning electron microscopy has shown that macrophage surface folds decrease dramatically after phagocytosis. The surface fold length (micrometer) per unit smooth sphere surface area (micrometer2) decreases from 1.3 +/- 0.3 micrometer-1 to 0.53 +/- 0.25 micrometer-1 when cells are incubated in the presence of specific anti-DNP antibody and vesicles at 37 degrees C. No significant effect was observed in the presence of antibody only or vesicles only. Our studies shown that phagocytosis is associated with a loss of cell surface folds and a loss of cell surface area, which is consonant with current views of the endocytic process. On the basis of our uptake data, we estimate that approximately 400 micrometer2 of vesicle surface membrane is internalized. The guinea pig macrophage plasma membrane has a total area of approximately 400 micrometer2 in control studies, whereas the cells have roughly 300 micrometer2 after phagocytosis. These estimates of surface areas include membrane ruffles and changes directly related to changes in cell volume. We suggest that during antibody-dependent phagocytosis a membrane reservoir is made available to the cell surface.

Labeling Techniques for the Analysis of Cell Surface Glycoproteins

1980 ◽  
Vol 38 ◽  
pp. 716-719
Author(s):  
R.S. Molday
Keyword(s):  
Cell Surface ◽  
Surface Membrane ◽  
Molecular Complexes ◽  
Biochemical Properties ◽  
Membrane Glycoproteins ◽  
Animal Cells ◽  
Membrane Components ◽  
Specific Membrane ◽  
Specific Label

Surface membranes of animal cells display a wide variety of glycoproteins, many of which serve as enzymes, transport components or receptors for extra-cellular molecules and molecular complexes. In recent years specific label-ing techniques have been developed to detect, quantitate and study the ultra-structural organization and biochemical properties of cell surface membrane glycoproteins. Studies utilizing these techniques have contributed to our general understanding of membrane structure and have provided some insight into the role of specific membrane components in cellular communication and regulation.

Surface membrane regeneration in deciliated Tetrahymena

1983 ◽  
Vol 62 (1) ◽  
pp. 407-417
Author(s):  
N.E. Williams
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Membrane Proteins ◽  
Cell Surface ◽  
Surface Membrane ◽  
Membrane System ◽  
Ciliated Protozoa ◽  
Membrane Flow ◽  
Transmission Electron ◽  
Surface Marking

The induced synthesis of identified surface membrane proteins has been demonstrated in deciliated Tetrahymena. Cells in the process of regenerating cilia were also studied using transmission electron microscopy in order to obtain information on the deployment of new membrane at the cell surface. The results obtained suggest a pattern of membrane flow that includes the ‘pellicular alveoli’, a subsurface membrane system characteristically present in ciliated protozoa. The results of 125I surface-marking experiments were consistent with the notion that new membrane is added initially in non-ciliated regions, then subsequently flows laterally to cover regenerating cilia.

Sign in / Sign up

Export Citation Format

Share Document