Cellular membranes: The isolation and characterization of the plasma and smooth membranes of hela cells

Bosmann, H.Bruce; Hagopian, Arpi; Eylar, E.H.

doi:10.1016/0003-9861(68)90008-8

Cited by 251 publications

(67 citation statements)

References 32 publications

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“…' Finally, the cell membrane fraction, morphologically the least satisfactory of our preparations, has the usual type of plasmalemmal enzyme activities and little else . In contrast to the situation in other tissues (7,25,33,34,36,37) it has no alkaline p-nitrophenylphosphatase activity, and its NADH-cytochrome c reductase, as well as part of the Mgt+-ATPase activity could be accounted for by mitochondrial contamination as indicated by experiments and calculations similar to those described in the case of zymogen granule membranes . ' Smooth microsomes, zymogen granule membranes, and plasmalemmal fractions have a rather similar lipid composition characterized by high sphingomyelin and cholesterol content (2) .…”

Section: Discussionmentioning

confidence: 74%

“…5'-nucleotidase (5, 9, 20-23, 25, 33-35), ß-leucyl naphthylamidase (22,25,33,36,37), and Mgt+-ATPase (5,20,22,(34)(35)(36)(37)(38) (Table II), are also highly concentrated in the pancreatic plasmalemmal fraction . In addition, they are present in different concentrations in smooth microsomes and zymogen granule membranes .…”

Section: Enzyme Activities In Pancreatic Cell Fractionsmentioning

confidence: 99%

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Composition of Cellular Membranes in the Pancreas of the Guinea Pig

Meldolesi

Jamieson

Palade

1971

The Journal of Cell Biology

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A comparative study of the enzymic activities of membrane fractions derived from guinea pig pancreatic homogenates has yielded the following results: Rough microsomal membranes (derived from the rough ER) have the reductase activities of the two microsomal electron transport systems but lack enzyme activities of Golgi-type (TPPase) and plasmalemmal-type (5'-nucleotidase, ß-leucyl naphthylamidase, Mg-ATPase). Smooth microsomal membranes (derived primarily from the Golgi complex), zymogen granule membranes, and plasmalemmal fractions possess overlapping enzyme activities of plasmalemmal type, in different relative concentrations for each fraction. In addition, the smooth microsomal membranes exhibit TPPase and ADPase activity and share with rough microsomes the reductase activities of the two electron transport chains. Taken together with recent data on the lipid composition of the same fractions (2), these results indicate that the membranes of the pancreatic exocrine cell are chemically and functionally distinct, and hence do not mix with one another during the transport of secretory products.

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Section: Discussionmentioning

confidence: 74%

Section: Enzyme Activities In Pancreatic Cell Fractionsmentioning

confidence: 99%

Composition of Cellular Membranes in the Pancreas of the Guinea Pig

Meldolesi

Jamieson

Palade

1971

The Journal of Cell Biology

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“…With few exceptions which could be ascribed to heavy microsomal contamination (52), sphingomyelin has been found in high concentration in plasmalemmal fractions isolated from liver homogenates (51, 53-58) (range from 14% [55] to 33% [56] of total phospholipids) and erythrocytes (59,60) . The same applies for cholesterol which is found in high concentrations in cell membrane fractions prepared from liver (51-58, 61, 62), intestinal brush borders (61,63,64), erythrocytes, 9 (59, 61), kidney (62), urinary bladder (65), and HeLa cells (66) .…”

Section: Washing Of Pancreatic Membranes With Albuminmentioning

confidence: 82%

Composition of Cellular Membranes in the Pancreas of the Guinea Pig

Meldolesi

Jamieson

Palade

1971

The Journal of Cell Biology

141

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1 3 0The lipid composition of rough and smooth microsomal membranes, zymogen granule membranes, and a plasmalemmal fraction from the guinea pig pancreatic exocrine cell has been determined . As a group, membranes of the smooth variety (i .e ., smooth microsomes, zymogen granule membranes, and the plasmalemma) were similar in their content of phospholipids, cholesterol and neutral lipids, and in the ratio of total lipids to membrane proteins . In contrast, rough microsomal membranes contained much less sphingomyelin and cholesterol and possessed a smaller lipid/protein ratio . All membrane fractions were unusually high in their content of lysolecithin (up to _~20% of the total phospholipids) and of neutral lipids, especially fatty acids . The lysolecithin content was shown to be due to the hydrolysis of membrane lecithin by pancreatic lipase ; the fatty acids, liberated by the action of lipase on endogenous triglyceride stores, are apparently scavenged by the membranes from the suspending media . Similar artifactually high levels of lysolecithin and fatty acids were noted in hepatic microsomes incubated with pancreatic postmicrosomal supernatant . E 600, an inhibitor of lipase, largely prevented the appearance of lysolecithin and fatty acids in pancreatic microsomes and in liver microsomes treated with pancreatic supernatant .In the first article of this series, we have described the separation of membrane subfractions from rough microsome-, smooth microsome-, and zymogen granule fractions isolated from homogenates of guinea pig pancreas . We have also shown that a cell membrane fraction can be obtained from the same source (1) .These fractions represent membrane-bounded compartments which are involved in the synthesis, segregation, intracellular transport, and discharge of secretory proteins . In an attempt to understand how the membranes of these compartments interact with one another during the secretory process, we have investigated their chemical composition and enzyme activities . In this paper the lipid composition of the membranes is described .At the onset of this study, we anticipated that a small fraction of the digestive enzymes stored in the gland, particularly in zymogen granules and in the duct system, could be released during tissue homogenization and fractionation and thereupon cause artifactual degradation and alteration of membrane components . In this respect, it has been reported that pancreatic lipase is active in the cold (2) and that at least some proteases may become activated during cell fractionation (3) . Indeed, our studies showed that released lipolytic enzymes extensively affect the lipid composition of the isolated membranes . These alterations have been evaluated and the data on membrane lipids have been corrected accordingly .

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“…Between 3 and 5 °. o of total cellular glucose 6-phosphatase activity, a standard marker enzyme of the endoplasmic reticulum (Bosmann et al, 1968: Bose & Brundige, 1972, was present in the plasma membrane preparations indicating that maximum contamination with endoplasmic reticulum accounted for no more than 10°o by weight. Sindbis virus was purified by three cycles of velocity gradient centrifugation (Waite & Pfefferkorn, 1968 ( 1951 ).…”

mentioning

confidence: 98%

The Ratio of Plasma Membrane Cholesterol to Phospholipid and the Inhibition of Sindbis Virus Maturation by Low NaCl Medium

Garry

Bostick

Schram

et al. 1985

Journal of General Virology

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SUMMARYSindbis virus maturation is inhibited by low NaCI medium in chick embryo cells and in one strain of BHK cells, but not in another strain of BHK cells which has a different passage history. The plasma membrane of the cells in which Sindbis virus maturation is resistant to low NaCl medium has a higher ratio of cholesterol to phospholipid than the other cells. Cholesterol-containing liposomes, but not cholesterol-free liposomes, can release Sindbis virus from low NaCl-inhibited cells. These results suggest that low NaCl medium may block Sindbis virus maturation by a mechanism which is influenced by the ratio of plasma membrane cholesterol to phospholipid.

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Cellular membranes: The isolation and characterization of the plasma and smooth membranes of hela cells

Cited by 251 publications

References 32 publications

Composition of Cellular Membranes in the Pancreas of the Guinea Pig

Composition of Cellular Membranes in the Pancreas of the Guinea Pig

Composition of Cellular Membranes in the Pancreas of the Guinea Pig

The Ratio of Plasma Membrane Cholesterol to Phospholipid and the Inhibition of Sindbis Virus Maturation by Low NaCl Medium

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