Cellular organelles: how lipids get there, and back

Meer, Gerrit van

doi:10.1016/s0962-8924(00)01851-1

Cited by 14 publications

(7 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although lipid rafts are considered as ubiquitous constituents of plasma membrane or Golgi, which is in agreement with the enrichment of lipid rafts in these loci, recent studies indicated that lipid rafts are similarly formed at the subcellular membranes with relatively low concentrations of cholesterol and glycosphingolipids (van Meer and van Genderen, 1994; van Meer, 2000). For example, it is known that mitochondrial membranes contain lipid rafts that are remodeled and redistributed during apoptotic and immune reaction, thus initiating cell death signals derived from mitochondria (Malorni et al, 2007).…”

Section: 1 Introductionmentioning

confidence: 63%

“…Overexpression of sigma-1 receptors increases ganglioside GD1a in plasma membrane rafts, the endproduct of the ganglioside synthesis, but decreases less-glycosylated precursors of GD1a such as GM1 and GM2 (Takebayashi et al, 2004b). Because the biosynthesis of glycopshingolipids downstream of ceramides is entirely processed at Golgi (van Meer, 2000), this finding suggests the sigma-1 receptor accelerating glycosylation of gangliosides at the Golgi apparatus. The reconstitution of plasma membrane rafts caused by sigma-1 receptors therefore promotes a significant alteration in signal transduction triggered by receptors of trophic factors as mentioned below.…”

Section: 7 Roles Of Sigma-1 Receptors In Subcellular Distribution mentioning

confidence: 96%

See 1 more Smart Citation

Cholesterol at the Endoplasmic Reticulum: Roles of the Sigma-1 Receptor Chaperone and Implications thereof in Human Diseases

Hayashi¹,

Su²

2010

Subcellular Biochemistry

View full text Add to dashboard Cite

Despite substantial data elucidating the roles of cholesterol in lipid rafts at the plasma membrane, the roles of cholesterol and related lipids in lipid raft microdomains at the level of subcellular membrane, such as the endoplasmic reticulum (ER) membrane, remain less understood. Growing evidence, however, begins to unveil the importance of cholesterol and lipids on the lipid raft at the ER membrane. A few ER proteins including the sigma-1 receptor chaperone were identified at lipid raft-like microdomains of the ER membrane. The sigma-1 receptor, which is highly expressed at a subdomain of ER membrane directly apposing mitochondria and known as the mitochondria-associated ER membrane or MAM, has been shown to associate with steroids as well as cholesterol. The sigma-1 receptor has been implicated in ER lipid metabolisms/transports, lipid raft reconstitution at the plasma membrane, trophic factor signalling, cellular differentiation, and cellular protection against β-amyloid-induced neurotoxicity. Recent studies on sigma-1 receptor chaperones and other ER proteins clearly suggest that cholesterol, in concert with those ER proteins, may regulate several important functions of the ER including folding, degradation, compartmentalization, and segregation of ER proteins, and the biosynthesis of sphingolipids.

show abstract

Section: 1 Introductionmentioning

confidence: 63%

Section: 7 Roles Of Sigma-1 Receptors In Subcellular Distribution mentioning

confidence: 96%

Cholesterol at the Endoplasmic Reticulum: Roles of the Sigma-1 Receptor Chaperone and Implications thereof in Human Diseases

Hayashi¹,

Su²

2010

Subcellular Biochemistry

View full text Add to dashboard Cite

show abstract

“…Our observation that the parasite's food vacuolar membrane is more susceptible to lipid peroxidation than the plasma membranes of the parasite or host erythrocyte is a reflection of the different contents of polyunsaturated fatty acids, which is usually higher in vacuolar membranes (39). This explains lysis of the food vacuole under conditions where the parasite plasma membrane and the erythrocyte plasma membrane remain intact and are still able to contain fluorescent dyes (Figs.…”

Section: Discussionmentioning

confidence: 85%

Illumination of the Malaria Parasite Plasmodium falciparum Alters Intracellular pH

Wissing

Sánchez

Rohrbach

et al. 2002

Journal of Biological Chemistry

View full text Add to dashboard Cite

Live cell fluorescence microscopy has been widely used to study physiological processes in the human malarial parasite Plasmodium falciparum, including pH homeostasis, Ca 2؉ signaling and protein targeting. However, the reproducibility of the data is often poor. Controversial statements exist regarding cytosolic and vacuolar baseline pH, as well as regarding the subcellular localization of some of the fluorochromes used. When trying to reproduce published baseline values, we observed an unexpected light sensitivity of P. falciparum, which manifests itself in the form of a strong cytoplasmic acidification. Even short exposure times with moderate to low light intensities caused the parasite cytosol to acidify. We show that this effect arises from the selective disruption of the parasite's acidic food vacuole, brought about by lipid peroxidation initiated by lightinduced generation of hydroxyl radicals. Our data suggest that heme serves as a photosensitizer in this process. Our findings have major implications for the use of live cell microscopy in P. falciparum and add a cautionary note to previous studies where live cell fluorometry has been used to determine physiological parameters in P. falciparum.Progress in understanding the physiology of the human malarial parasite Plasmodium falciparum has been slow, despite the fact that P. falciparum is a major health problem, killing millions of humans every year (1). As a consequence, only a limited number of potential drug targets have been identified in recent years. One reason for this is the obligatory intracellular life style of the parasite, which has complicated access to biochemical and physiological pathways.A powerful method to investigate physiological processes of intact cells, under non-disruptive conditions, is live cell fluorescence microscopy. This technique has recently been applied to the intraerythrocytic stages of P. falciparum for measuring intracellular pH, ion concentrations, Ca 2ϩ signaling, and protein targeting (2-7). The main advantage of live cell fluorescence microscopy is that it allows for the spatial separation of signals originating from the parasite and from the surrounding infected erythrocyte. Even subcellular compartments, such as the parasite's acidic food vacuole, can be visualized in situ using this method (5). However, a number of concerns have recently been raised about using single cell fluorescence microscopy in P. falciparum (8).A major disadvantage is the variability between cells, requiring a relatively large number of determinations to obtain statistically significant measurements. Reproducibility between different laboratories seems to be low as well when data obtained from single cell measurements are compared. For example, although some studies have found differences in the parasite's cytosolic pH between chloroquine-sensitive and chloroquine-resistant P. falciparum strains, other studies could not verify this observation (7, 9 -12). Another example represents the use of acridine orange (AO) 1 in the measurement of the...

show abstract

“…Though the ER synthesizes almost all types of lipids or their precursors including cholesterols and sphingolipids, those lipids are actively transported by vesicular and nonvesicular systems to the Golgi apparatus ( van Meer, 2000; van Meer and van Genderen, 1994). In contrast to the growing number of MAM-enriched proteins, the lipid compositions of the MAM are largely unknown.…”

Section: Lipid Components Of the Mammentioning

confidence: 99%

New Insights into the Role of Mitochondria-Associated Endoplasmic Reticulum Membrane

Fujimoto

Hayashi

2011

International Review of Cell and Molecular Biology

View full text Add to dashboard Cite

Cellular organelles: how lipids get there, and back

Cited by 14 publications

References 14 publications

Cholesterol at the Endoplasmic Reticulum: Roles of the Sigma-1 Receptor Chaperone and Implications thereof in Human Diseases

Cholesterol at the Endoplasmic Reticulum: Roles of the Sigma-1 Receptor Chaperone and Implications thereof in Human Diseases

Illumination of the Malaria Parasite Plasmodium falciparum Alters Intracellular pH

New Insights into the Role of Mitochondria-Associated Endoplasmic Reticulum Membrane

Contact Info

Product

Resources

About