Plasma membrane isolation

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M. J. Holden, D. G. Luster, R. L. Chaney, T. J. Buckhout. and C. Robinson, Fc -chelate reductase activity of plasma membranes isolated from tomato (Lyco-persicon escidentiim Mill.) roots. Comparison of enzymes from Fe-deficient and Fe-sufficient roots. Plant Physiol. 97 531 (1991). 

Benedetti E, Emmelot P. Electron microscopic observations on negatively- stained plasma membranes isolated from rat liver. J Cell Biol 1965 26 299-304. 

B. S. Jacobson, J. Cronin, and D. Branton, Coupling polylysine to glass beads for plasma membrane isolation, Biochim. Biophys. Ada 506, 81-96 (1978). 

Pfleger, R. C., Anderson, N. G. and Snyder, F. 1968. Lipid class and fatty acid composition of rat liver plasma membranes isolated by zonal centrifugation. Biochemistry 7, 2826-2833. 

Likewise, in goldfish, Rosenblum et al.146 have characterized the interaction of the steroidal pheromone 17a, 3-dihydroxy-4-pregnen-3-one to a plasma membrane isolated from the animal s olfactory epithelium. In an attempt to elucidate the molecular basis of pheromone recognition, Cao... 

Wheeler, J.J., and Boss, W.F., 1987, Polyphosphoinositides are present in plasma membranes isolated from fusogenic carrot cells. Plant Physiol. 85 389-392. 

These results have been compared to a systematic analysis of a classical plasma membrane protein preparation, generated by ultracentrifiigation (100,000 g on sucrose). This plasma membrane isolation has allowed the identification of 292 proteins, and only 69 proteins were located to the plasma membrane (24 vs. 34% for the microparticles preparation). Moreover, 75 plasma membrane proteins were identified specifically in the microparticles preparation, and only 9 were identified only in the plasma membrane preparation. These results are summarized in Figure 6. 

Carafoli, E. (1984). Calmodulin-sensitive calcium-pumping ATPase of plasma membranes Isolation, reconstitution and regulation. Fed. Proc. 43, 3005-3010. 

Earlier experiments of Evans and Ray (1969) with substances inhibiting protein synthesis also seem to disprove the theory that disturbance of protein synthesis is a fundamental determinant of biological action. Rubery and Northcote (1970) proved by in vivo experiments that herbicides with auxin action stimulate cell wall synthesis. The investigations carried out on cell-free plasma membranes isolated from onion stalk treated with 2,4-D, furnished further proof of the stimulation of polysaccharide synthesis. 

Transport of newly synthesized PC from the ER to the plasma membrane. The principal site of PC synthesis is the ER and Golgi (Chapter 8). The transport of PC from its sites of synthesis to the plasma membrane has been examined using pulse-chase labeling with a [ Hjcholine precursor for PC, and rapid plasma membrane isolation with cationic beads (M. Kaplan, 1985). These studies reveal that PC transport is an extremely rapid process occurring with a 1 min (Fig. 8). This transport is unaffected by metabolic poisons that deplete cellular ATP levels, disrupt vesicle transport, or alter cytoskeletal arrangement. 

Transport of cholesterol to and from the plasma membrane. Following its synthesis at the ER, cholesterol is transported throughout the cell and becomes enriched in the plasma membrane [7]. The transport of newly synthesized cholesterol to the plasma membrane has been examined in tissue culture cells using pulse-chase experiments with either the rapid plasma membrane isolation procedure (M. Kaplan, 1985), caveolae isolation (A. Uittenbogaard,... 

Westergren, T. Ekblad, L. Jergil, B. Sommarin, M. Phosphatidylinositol 4-kinase associated with spinach plasma membranes. Isolation and characterization of two distinct forms. Plant Physiol., 121, 507-516 (1999)... 

Currently, several methods are available for the bulk isolation of purified plasma membrane fractions. Each of these plasma membrane isolation procedures involves three basic, successive steps tissue homogenization, subcellular fi-actionation, and assessment of the yield and/or purity of the isolated membrane fraction. During homogenization of brain tissue, nerve terminals are pinched off from their axonal connections and broken away from surrounding glial cell elements. Because nerve terminals are relatively resistant to mechanical stress, they can reseal to form synaptic bodies that are known as synaptosomes. Whittaker (4) and deRobertis (5) were the first to describe a method to purify these pinched-off nerve terminals. In their procedure, a crude... 

Freeze-etch preparations of sterol-containing liposomes or erythrocyte membranes treated with amphotericin B did not reveal pits [256]. The postulated amphotericin B—sterol pores would be too small to be seen by this technique. However, freeze-etch studies of amphotericin B-treated plasma membranes isolated from Epidermophyton floccosum [261 ], a fungus pathogenic to man, has revealed depressions (or craters) and aggregates of membrane-associated particles (85 A in diameter). The areas of disruption did not traverse the membrane. 

Most substances dissolved in the medium surrounding yeast cells diffuse freely through the cell walls to the plasma membranes. There is adsorption of certain materials by the outer layers of the cell walls during the diffusion. For instance, hop bitter substances, polyphenols, and nitrogenous compounds of wort tend to be adsorbed. The plasma membrane isolates the living cell or protoplast from its environment and controls the movement of materials in and out of the cell. Substances which are soluble in lipid, an important constituent of the membrane, tend to penetrate readily. Thus, unbranched long-chain fatty acids and a-oxo-acids penetrate more quickly than the corresponding short-chain acids which are less soluble in lipid. If the acids are dissociated, they enter the cell either slowly or not at all. 

With the development of methods for plasma membrane isolation, adenyl cyclase assay, and measurement of binding of hormone to its receptor, it is now possible to study the major components of a hormone receptor. 

There is a scarcity of data for the analyses of glyoxysomal membranes and plasma membranes of plant cells. The glyoxysomal membrane from castor bean (Ricinus communis L.) endosperm has PC as the major lipid together with PE, 80% of the phospholipid can be accounted for. Plasma membranes isolated from oat Avena saliva L.) roots showed relatively lai ge amounts of phosphatidic acid (PA), (1,2-diacyl-jn-glycerol 3-phosphate) and an unknown lipid (Keenan et al., 1973). It is possible that some lipid degradation took place in the preparation of this sample. Further analyses of the lipid composition would be most appropriate. The analyses of Keenan et al. (1973) indicated that only 28.6% of the plasma membrane lipid was phospho-... 

Another approach to the study of membrane asymmetry has been based on the morphological and functional asymmetry of cells from organized tissues. Cellular polarity is expressed in the diverse biochemistry of the various membrane portions and refinements in plasma membrane isolation procedures have met with considerable success in ascribing membrane elements to topographical aspects of the cell. For instance, hepatocyte bile front has been separated from the sinus front and the contiguous membrane (EVANS 6e GURD,... 

Plasma membranes isolated from paclobutrazol treated Agraveolens cells exhibited a reduced membrane fluidity and an accumulation of 14a-methylsterols(mainly obtusifoliol) accompanied by a decrease in phospholipid sterol ratio. In addition, the relative proportions of phosphatidylethanolamlne was reduced and that of phosphatidylserine was increased. A direct carboxylation of existing phosphatidylethanolamlne molecules could account for this latter observation [13]. In contrast, mitochondrial membranes exhibited an... 

Figure 6. Vesicle sidedness of plasma membrane isolated from bell pepper fruit tissue.

Since plasma membranes isolated from etiolated leek seedlings are incapable of synthesizing VLCFA,as is the case of the plasma membrane Isolated from leek epidermis, it follows that the VLCFA were transferred to the plasmalemma vivo. 

Sandelius AS, Barr R, Crane FL, Morrd DJ. Redox reactions of plasma membranes isolated from soybean hypocotyls by phase partition. Plant Sci. 1986 1-10. 

Benedetti, E. L., and Emmelot, P., 1968, Structure and fimction of plasma membranes isolated from liver, in Ultrastructure in Biological Systems, Vol. 4, The Membranes (A. J. Dalton and F. Haguenau, eds.), pp. 33-121, Academic Press, New York. 

Emmelot, P., Bos, C. J., Benedetti, E. L., and Riimke, P. H., 1964, Studies on plasma membranes I. Chemical composition and enzyme content of plasma membranes isolated from rat liver, Biochim. Biophys. Acta 90 126. 

Purdue, J. F., Warner, D., and Miller, K., 1973, The isolation and characterization of plasma membrane from cultured cells. III. The chemical composition of plasma membrane isolated from chicken tumors initiated with virus-transformed cells, Biochim. Biophys. Acta 298 817-826. 

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