scholarly journals Peripheral proteins and smooth membrane from erythrocyte ghosts. Segregation of ATP-utilizing enzymes into smooth membrane.

1978 ◽  
Vol 76 (1) ◽  
pp. 105-115 ◽  
Author(s):  
H Hayashi ◽  
H W Jarrett ◽  
J T Penniston
Keyword(s):  
Atpase Activity ◽  
Actin Filaments ◽  
Energy Production ◽  
Cooperative Interaction ◽  
Erythrocyte Membranes ◽  
Erythrocyte Ghosts ◽  
Peripheral Proteins ◽  
Smooth Membrane ◽  
Integral Proteins ◽  
Membranous Material

Erythrocytes and their isolated membranes display ATP-dependent endocytosis. To localize the enzymes responsible for this phenomenon, the erythrocyte membranes (ghosts) were fractionated under conditions which retained ATPase activity. Fractionation of the ghosts resulted in three fractions: spectrin-actin, the peripheral proteins soluble in high salt, and the smooth membrane containing integral proteins. On the average, 87% of the protein and 88% of the phosphorus of the original ghosts were recovered in these fractions, and all of the kinds of ATP-splitting activities of the membrane were recovered in the smooth membrane. A tiny ATPase activity, detectable by special methodology in spectrinactin, could have been due to contamination with membranous material. Although the purified spectrin-actin did not have a significant ATPase of its own, it stimulated the Ca2+, Mg2+-ATPase of the smooth membrane significantly, suggesting a cooperative interaction between these two fractions. This segregation of the ATPase activities into the smooth membrane, combined with the energy dependence of endocytosis, showed that the smooth membrane must be involved in the energy production for endocytosis. The possibility that the spectrin-actin filaments cooperate with a myosinlike ATPase in the membrane to generate membrane movements is discussed.

scholarly journals Interactions of actin, myosin, and a new actin-binding protein of rabbit pulmonary macrophages. II. Role in cytoplasmic movement and phagocytosis.

1976 ◽  
Vol 68 (3) ◽  
pp. 602-619 ◽  
Author(s):  
T P Stossel ◽  
J H Hartwig
Keyword(s):  
Molecular Weight ◽  
Atpase Activity ◽  
Actin Filaments ◽  
Sucrose Solution ◽  
Binding Protein ◽  
Cooperative Interaction ◽  
Actin Binding ◽  
Temperature Dependent ◽  
Actin Binding Protein ◽  
Pulmonary Macrophages

Actin and myosin of rabbit pulmonary macrophages are influenced by two other proteins. A protein cofactor is required for the actin activation of macrophage myosin Mg2 ATPase activity, and a high molecular weight actin-binding protein aggregates actin filaments (Stossel T.P., and J.H. Hartwig. 1975. J. Biol. Chem. 250:5706-5711)9 When warmed in 0.34 M sucrose solution containing Mg2-ATP and dithiothreitol, these four proteins interact cooperatively. Acin-binding protein in the presence of actin causes the actin to form a gel, which liquifies when cooled. The myosin contracts the gel into an aggregate, and the rate of aggregation is accelerated by the cofactor. Therefore, we believe that these four proteins also effec the temperature-dependent gelation and aggregation of crude sucrose extracts pulmonary macrophages containing Mg2-ATP and dithiothreitol. The gelled extracts are composed of tangled filaments. Relative to homogenates of resting macrophages, the distribution of actin-binding protein in homogenates of phagocytizing macrophages is altered such that 2-6 times more actin-binding protein is soluble. Sucrose extracts of phagocytizing macrophages gel more rapidly than extracts of resting macrophages. Phagocytosis by pulmonary macrophages involves the formation of peripheral pseudopods containing filaments. The findings suggest that the actin-binding protein initiates a cooperative interaction of contractile proteins to generate cytoplasmic gelation, and that phagocytosis influences the behavior of the actin-binding protein.

Effect of Integral Proteins on Frozen Membrane Fracture

1980 ◽  
Vol 38 ◽  
pp. 756-759 ◽  
Author(s):  
S. Kirchanski ◽  
D. Branton
Keyword(s):  
Lipid Bilayers ◽  
Freeze Fracture ◽  
Covalent Bond ◽  
Erythrocyte Membranes ◽  
Glycophorin A ◽  
Experimental Protocol ◽  
Transmembrane Glycoprotein ◽  
Bond Breakage ◽  
Human Erythrocyte Membranes ◽  
Integral Proteins

We have investigated the effect of integral membrane proteins upon the fracturing of frozen lipid bilayers. This investigation has been part of an effort to develop freeze fracture labeling techniques and to assess the possible breakage of covalent protein bonds during the freeze fracture process. We have developed an experimental protocol utilizing lectin affinity columns which should detect small amounts of covalent bond breakage during the fracture of liposomes containing purified (1) glycophorin (a transmembrane glycoprotein of human erythrocyte membranes). To fracture liposomes in bulk, frozen liposomes are ground repeatedly under liquid nitrogen. Failure to detect any significant covalent bond breakage (contrary to (2)) led us to question the effectiveness of our grinding procedure in fracturing and splitting lipid bilayers.

scholarly journals Ultrastructure of the intact skeleton of the human erythrocyte membrane.

1986 ◽  
Vol 102 (3) ◽  
pp. 997-1006 ◽  
Author(s):  
B W Shen ◽  
R Josephs ◽  
T L Steck
Keyword(s):  
Human Erythrocyte ◽  
Actin Filaments ◽  
Band 3 ◽  
Carbon Films ◽  
Erythrocyte Membranes ◽  
Accessory Proteins ◽  
Red Cell Membrane ◽  
Human Erythrocyte Membranes ◽  
Low Ionic Strength ◽  
Triton X

Filamentous skeletons were liberated from isolated human erythrocyte membranes in Triton X-100, spread on fenestrated carbon films, negatively stained, and viewed intact and unfixed in the transmission electron microscope. Two forms of the skeleton were examined: (a) basic skeletons, stripped of accessory proteins with 1.5 M NaCl so that they contain predominantly polypeptide bands 1, 2, 4.1, and 5; and (b) unstripped skeletons, which also bore accessory proteins such as ankyrin and band 3 and small plaques of residual lipid. Freshly prepared skeletons were highly condensed. Incubation at low ionic strength and in the presence of dithiothreitol for an hour or more caused an expansion of the skeletons, which greatly increased the visibility of their elements. The expansion may reflect the opening of spectrin from a compact to an elongated disposition. Expanded skeletons appeared to be organized as networks of short actin filaments joined by multiple (5-8) spectrin tetramers. In unstripped preparations, globular masses were observed near the centers of the spectrin filaments, probably corresponding to complexes of ankyrin with band 3 oligomers. Some of these globules linked pairs of spectrin filaments. Skeletons prepared with a minimum of perturbation had thickened actin protofilaments, presumably reflecting the presence of accessory proteins. The length of these actin filaments was highly uniform, averaging 33 +/- 5 nm. This is the length of nonmuscle tropomyosin. Since there is almost enough tropomyosin present to saturate the F-actin, our data support the hypothesis that tropomyosin may determine the length of actin protofilaments in the red cell membrane.

Further analysis of cell membrane changes in genetic hypertension in rats by diphenylhexatriene fluorescence polarization

1984 ◽  
Vol 66 (6) ◽  
pp. 717-723 ◽  
Author(s):  
I. Aracon-Birlouez ◽  
T. Montenay-Carestier ◽  
M. A. Devynck
Keyword(s):  
Spontaneously Hypertensive Rats ◽  
Erythrocyte Membranes ◽  
Shr Rats ◽  
Erythrocyte Ghosts ◽  
Hypertensive Rats ◽  
Salt Loading ◽  
Spontaneously Hypertensive ◽  
Platelet Membranes ◽  
Wistar Kyoto ◽  
Membrane Changes

1. Fluorescence Dolarization of dbhenvlhexa-triene embedded in membranes was used as an index of ‘microviscosity’ in platelets and ervthro—cyte ghosts of spontaneously hypertensive rats of the Okamoto-Aoki strain (SHR), Wistar-Kyoto strain (WKY) and of the hypertension-prone and -resistant Sabra strains (SBH and SBN), and the original Sabra strain (SB). 2. Microviscosity was increased both in erythrocyte ghosts and platelet membranes of male but not female SHR rats compared with WKY rats and in hypertension-prone Sabra rats compared with the original Sabra rats. 3. Acute and chronic salt loading increased the microviscosity of platelet membranes in all strains of rats but had no effect on the erythrocyte membranes. 4. Microviscosities of vesicles made of lipids extracted from SHR and WKY erythrocyte ghosts were similar. This supports the hypothesis that membrane proteins play a major role in the differences in microviscosity observed in SHR rats.

Effect of Aging on the Activities of Acetylcholinesterase, Na+, K+-ATPase and Mg2+-ATPase in Rat Pituitary and Hypothalamus

1998 ◽  
Vol 53 (3-4) ◽  
pp. 168-172 ◽  
Author(s):  
Stylianos Tsakiris ◽  
Panagoula Angelogianni ◽  
John C. Stavridis
Keyword(s):  
Atpase Activity ◽  
Ache Activity ◽  
Energy Production ◽  
Metabolic Energy ◽  
Adult Rats ◽  
Neural Excitability ◽  
Age Related ◽  
Rat Pituitary ◽  
Old Rats

Abstract Acetylcholinesterase (AChE), Na+, K+-ATPase and Mg2+-ATPase activities were esti­mated in homogenised rat pituitary and hypothalamus of 4-and 22-month-old rats. AChE activity was not altered in the pituitary of aged com pared to adult rats, while it was found decreased by about 40% in the hypothalamus. Na+,K+-ATPase activity remained stable in the hypothalamus, while it was decreased by about 38% in the pituitary. Mg2+-ATPase activ­ity remained unchanged in the hypothalamus, but was increased by about 83% in the pitu­itary. This pituitary Na+, K+-ATPase inactivation may result in pathological mood and de­creased neural excitability and metabolic energy production in aged animals.The age-related alterations of AChE , Na+, K+-ATPase and Mg2+-ATPase activities may reflect changes in secretion and responses of some hormones of pituitary and hypothalamus.

scholarly journals Calcium-ATPase Activity in Cystic Fibrosis Erythrocyte Membranes: Decreased Activity in Patients with Pancreatic Insufficiency

1984 ◽  
Vol 18 (9) ◽  
pp. 890-895 ◽  
Author(s):  
Dorr G Dearborn ◽  
Robert J Wityk ◽  
Lynelle R Johnson ◽  
Louis Poncz ◽  
Robert C Stern
Keyword(s):  
Cystic Fibrosis ◽  
Atpase Activity ◽  
Pancreatic Insufficiency ◽  
Calcium Atpase ◽  
Erythrocyte Membranes

Changes in Erythrocyte Membrane Ouabain-Sensitive Adenosine Triphosphatase after Renal Transplantation

1975 ◽  
Vol 48 (3) ◽  
pp. 239-242 ◽  
Author(s):  
C. H. Cole ◽  
R. Maletz
Keyword(s):  
Renal Transplantation ◽  
Atpase Activity ◽  
Erythrocyte Membrane ◽  
Adenosine Triphosphatase ◽  
Inorganic Phosphorus ◽  
Erythrocyte Membranes ◽  
Healthy Controls ◽  
Intracellular Electrolytes ◽  
Transplant Patients ◽  
The Mean

1. Intracellular electrolytes, and erythrocyte membrane adenosine triphosphatase (ATPase) activity, was studied in twenty patients after renal transplantation. 2. The mean ouabain-sensitive ATPase activity in the erythrocyte membranes of the transplant patients was 122 nmol of inorganic phosphorus (Pi) h−1 mg of tissue−1 (sem 14), compared with 62 nmol of Pi h−1 mg of tissue−1 (sem 8) in a group of paired, healthy controls. 3. The increase in ouabain-sensitive ATPase was most marked in the 4 months after transplantation. However, a significant increase in ouabain-sensitive ATPase persisted for more than 8 months after transplantation. 4. This increase in ouabain-sensitive ATPase was associated with a decrease in intracellular sodium in the erythrocytes of the transplant patients.

Effect of a Hyperlipidic Diet on Lipid Composition, Fluidity, and (Na+-K+)ATPase Activity of Rat Erythrocyte Membranes

1989 ◽  
Vol 8 (1) ◽  
pp. 11-18 ◽  
Author(s):  
A. Bordoni ◽  
P. L. Biagi ◽  
G. Parenti Castelli ◽  
S. Hrelia ◽  
C. A. Rossi ◽  
...  
Keyword(s):  
Atpase Activity ◽  
Lipid Composition ◽  
Erythrocyte Membranes ◽  
Hyperlipidic Diet
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