Calcium-induced transbilayer scrambling of fluorescent phospholipid analogs in platelets and erythrocytes

Smeets, E. F.; Comfurius, Paul; Bevers, Edouard M.; Zwaal, R.F.A.

doi:10.1016/0005-2736(94)90268-2

Cited by 117 publications

(116 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Most of the polypeptide (residues 1-290) thereby extends from the cytoplasmic membrane leaflet, leaving a short exoplasmic tail (residues 310 -318). The predicted orientation of this protein is consistent with the anticipated topology of PL scramblase in the erythrocyte membrane, where lipid-mobilizing function is responsive to [Ca 2ϩ ] only at the endofacial surface of the membrane (3,5,10,11,15,16).…”

Section: Resultssupporting

confidence: 72%

“…An increase in intracellular Ca 2ϩ due to either cell activation, cell injury, or apoptosis causes a rapid bidirectional movement of the plasma membrane PL between leaflets, resulting in exposure of PS and phosphatidylethanolamine at the cell surface (1,(3)(4)(5). This exposure of the plasma membrane aminophospholipids has been shown to promote assembly and activation of several key enzymes of the coagulation and complement systems, as well as to accelerate the clearance of injured or apoptotic cells by the reticuloendothelial system, suggesting that Ca 2ϩ -induced remodeling of plasma membrane PL is central to both vascular hemostatic and cellular clearance mechanisms (1, 6 -9).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Molecular Cloning of Human Plasma Membrane Phospholipid Scramblase

Zhou¹,

Zhao

Stout

et al. 1997

Journal of Biological Chemistry

375

182

View full text Add to dashboard Cite

The rapid movement of phospholipids (PL) between plasma membrane leaflets in response to increased intracellular Ca 2؉ is thought to play a key role in expression of platelet procoagulant activity and in clearance of injured or apoptotic cells. We recently reported isolation of a ϳ37-kDa protein in erythrocyte membrane that mediates Ca 2؉ -dependent movement of PL between membrane leaflets, similar to that observed upon elevation of Ca 2؉ in the cytosol (Bassé , F., Stout, J. G., Sims, P. J., and Wiedmer, T. (1996) J. Biol. Chem. 271, 17205-17210). Based on internal peptide sequence obtained from this protein, a 1,445-base pair cDNA was cloned from a K-562 cDNA library. The deduced ''PL scramblase'' protein is a proline-rich, type II plasma membrane protein with a single transmembrane segment near the C terminus. Antibody against the deduced Cterminal peptide was found to precipitate the ϳ37-kDa red blood cell protein and absorb PL scramblase activity, confirming the identity of the cloned cDNA to erythrocyte PL scramblase. Ca 2؉ -dependent PL scramblase activity was also demonstrated in recombinant protein expressed from plasmid containing the cDNA. Quantitative immunoblotting revealed an approximately 10-fold higher abundance of PL scramblase in platelet (ϳ10 4 molecules/cell) than in erythrocyte (ϳ10 3 molecules/ cell), consistent with apparent increased PL scramblase activity of the platelet plasma membrane. PL scramblase mRNA was found in a variety of hematologic and nonhematologic cells and tissues, suggesting that this protein functions in all cells.

show abstract

Section: Resultssupporting

confidence: 72%

mentioning

confidence: 99%

Molecular Cloning of Human Plasma Membrane Phospholipid Scramblase

Zhou¹,

Zhao

Stout

et al. 1997

Journal of Biological Chemistry

375

182

View full text Add to dashboard Cite

show abstract

“…The flip-flop speed cannot be explained only as a diffusion-controlled process because the rate of passive lipid transbilayer diffusion is too slow [26]. So-called scramblases are considered to be responsible for the translocation of aminophospholipids [27,28], accompanied by a down regulation of an ATPdependent aminophospholipid translocase, which directs PS to the inner membrane leaflet. It is worthy to consider how the loss of lipid asymmetry is related to other apoptotic features?…”

Section: Discussionmentioning

confidence: 99%

Kinetics of apoptotic markers in exogeneously induced apoptosis of EL4 cells

Jessel

Haertel

Socaciu

et al. 2002

J Cellular Molecular Medi

View full text Add to dashboard Cite

We investigated the time‐dependence of apoptotic events in EL4 cells by monitoring plasma membrane changes in correlation to DNA fragmentation and cell shrinkage. We applied three apoptosis inducers (staurosporine, tubericidine and X‐rays) and we looked at various markers to follow the early‐to‐late apoptotic events: phospholipid translocation (identified through annexin V‐fluorescein assay and propidium iodide), lipid package (via merocyanine assay), membrane fluidity and anisotropy (via fluorescent measurements), DNA fragmentation by the fluorescence‐labeling test and cell size measurements. The different apoptotic inducers caused different reactions of the cells: staurosporine induced apoptosis most rapidly in a high number of cells, tubercidine triggered apoptosis only in the S phase cells, while X‐rays caused a G2/M arrest and subsequently apoptosis. Loss of lipid asymmetry is promptly detectable after one hour of incubation time. The phosphatidylserine translocation, decrease of lipid package and anisotropy, and the increase of membrane fluidity appeared to be based on the same process of lipid asymmetry loss. Therefore, the DNA fragmentation and the cell shrinkage appear to be parallel and independent processes running on different time scales but which are kinetically inter‐related. The results indicate different signal steps to apoptosis dependent on inducer characteristics but the kinetics of “early‐to‐late” apoptosis appears to be a fixed program.

show abstract

“…This has been ascribed to the activation of the lipid scramblase, a putative membrane protein facilitating a rapid bi-directional movement of all major phospolipid classes between the leaflets of the plasma membrane (Smeets et al, 1994;Williamson et al, 1995). However, for PS and PE a vectorial efflux from the inner to the outer leaflet upon activation of a scramblase activity has been reported (Gaffet et al, 1995; Hamon et al, 2000).…”

Section: Flippases and Their Biological Functionsmentioning

confidence: 99%

Tracking down lipid flippases and their biological functions

Pomorski

Holthuis

Herrmann

et al. 2004

Journal of Cell Science

180

127

View full text Add to dashboard Cite

IntroductionEukaryotic cells are compartmentalized into distinct organelles by lipid bilayers. Each membrane is composed of hundreds of lipids, and there are dramatic differences between organellesfor example, sphingomyelin and sterols are highly enriched at the plasma membrane (Fig. 1). Even within a membrane, lipids are not randomly distributed. Lipids are asymmetrically arranged between the two leaflets of the plasma membrane, and this was first thought to be a static characteristic of membranes (Bretscher, 1972). However, it is now clear that the lipid topology results from a continuous bi-directional movement of lipids between the two leaflets -so-called 'flip-flop' -in which specific membrane proteins have an essential role. Recently, several 'lipid flippases' have been identified. Besides maintaining an asymmetric lipid arrangement, the physiological functions of which are still relatively unclear, these appear to regulate other, more dynamic events, such as the budding of intracellular transport vesicles. Lipid movement in model membranesThe most prevalent phospholipid in eukaryotic cell membranes is phosphatidylcholine (PC). In water, the cylindrical and amphipathic PC spontaneously forms bilayer membranes: its polar head is exposed to water and the hydrocarbon chains constitute the hydrophobic core of the bilayer. In biomembranes, lipids diffuse laterally over an area of 1 µm 2 within seconds. However, the rate of spontaneous flip-flop between leaflets differs for each lipid. Phospholipids that have polar head groups, such as PC, phosphatidylserine (PS) and phosphatidylethanolamine (PE), and glycolipids that have bulky hydrophilic carbohydrate moieties flip only slowly across a pure lipid bilayer, displaying half-times of hours to days depending on the size and charge of the head group (Kornberg and McConnell, 1971;Buton et al., 2002). By contrast, neutral lipids such as diacylglycerol and charged lipids such as free fatty acids, phosphatidic acid or phosphatidylglycerol in their protonated form can move rapidly from one leaflet to the other in seconds or minutes. Cholesterol is embedded in the membrane; with its polar OH group facing the aqueous phase and the acyl chain pointing towards the bilayer center. Recent experimental evidence supports rapid flip-flop of cholesterol in PC membranes, red cell membranes and, presumably, in most other cellular membranes (reviewed in Hamilton, 2003).Studies of model membranes have shown that lipid flip-flop is affected by the physical properties of the bilayer. An essential factor is the lipid packing. At temperatures above the solid-liquid phase transition, flip-flop of short-chain phospholipids in human erythrocytes and PC membranes is reduced by cholesterol (Morrot et al., 1989; John et al., 2002). Cholesterol condenses the phospholipid arrangement and increases the thickness of the hydrophobic core. Indeed, plasma membranes are thought to contain less-fluid patches enriched in cholesterol, so-called sphingolipid-cholesterol rafts (Harder and van Meer, 2003). I...

show abstract

Calcium-induced transbilayer scrambling of fluorescent phospholipid analogs in platelets and erythrocytes

Cited by 117 publications

References 42 publications

Molecular Cloning of Human Plasma Membrane Phospholipid Scramblase

Molecular Cloning of Human Plasma Membrane Phospholipid Scramblase

Kinetics of apoptotic markers in exogeneously induced apoptosis of EL4 cells

Tracking down lipid flippases and their biological functions

Contact Info

Product

Resources

About