scholarly journals Regulation of plasma membrane receptors by a new autophagy-related BECN/Beclin family member

Autophagy ◽  
2014 ◽  
Vol 10 (8) ◽  
pp. 1472-1473
Author(s):  
Weiran Zhang ◽  
Congcong He
Keyword(s):  
Plasma Membrane ◽  
Family Member ◽  
Membrane Receptors ◽  
Plasma Membrane Receptors

scholarly journals Plasma membrane glycosphingolipid signaling: a turning point

2021 ◽  
Author(s):  
Elena Chiricozzi
Keyword(s):  
Plasma Membrane ◽  
Chemical Synthesis ◽  
Bioinformatic Analysis ◽  
Membrane Receptors ◽  
Outer Side ◽  
Neuronal Homeostasis ◽  
Extracellular Stimuli ◽  
Conceptual Shift ◽  
Plasma Membrane Receptors ◽  
Key Events

AbstractPlasma membrane interaction is highly recognized as an essential step to start the intracellular events in response to extracellular stimuli. The ways in which these interactions take place are less clear and detailed. Over the last decade my research has focused on developing the understanding of the glycosphingolipids-protein interaction that occurs at cell surface. By using chemical synthesis and biochemical approaches we have characterized some fundamental interactions that are key events both in the immune response and in the maintenance of neuronal homeostasis. In particular, for the first time it has been demonstrated that a glycolipid, present on the outer side of the membrane, the long-chain lactosylceramide, is able to directly modulate a cytosolic protein. But the real conceptual change was the demonstration that the GM1 oligosaccharide chain is able, alone, to replicate numerous functions of GM1 ganglioside and to directly interact with plasma membrane receptors by activating specific cellular signaling. In this conceptual shift, the development and application of multidisciplinary techniques in the field of biochemistry, from chemical synthesis to bioinformatic analysis, as well as discussions with several national and international colleagues have played a key role.

Developmentally regulated expression of insulin-like growth factors by differentiated murine teratocarcinomas and extraembryonic mesoderm

Development ◽  
1986 ◽  
Vol 95 (1) ◽  
pp. 193-212
Author(s):  
John K. Heath ◽  
Wai-Kang Shi
Keyword(s):  
Plasma Membrane ◽  
Binding Protein ◽  
Membrane Receptors ◽  
Developmentally Regulated ◽  
Igf Receptors ◽  
Igf Binding ◽  
Plasma Membrane Receptors ◽  
Igf Binding Protein ◽  
Culture Supernatants ◽  
Insulin Like Growth Factors

The expression of plasma membrane receptors for insulin-like growth factors (IGFs) by PC13 embryonal carcinoma (EC) cells, and their immediate differentiated progeny PC13END was examined by binding radiolabelled IGF-I to cell monolayers. Both cell types express high-affinity IGF receptors, but the apparent number of unoccupied receptor sites falls by about 60% upon differentiation. Crosslinking studies reveal that both type 1 and type 2 IGF receptors are expressed by PC13EC cells. PC13END-cell-conditioned medium contains developmentally regulated, separable activities, one of which reacts directly with IGF-II, and the other with IGF for plasma membrane receptors. The former activity represents a soluble secreted IGF-binding protein. The latter activity is structurally and functionally similar to rat IGF-II. Polyclonal antibodies raised against purified rat IGF-II specifically recognize multiple forms of IGF in radiolabelled culture supernatants and material which closely resembles the soluble IGF-binding protein. Immunoprecipitation of radiolabelled culture supernatants with anti-rat IGF-II reveals that the differentiation of PC13EC cells is accompanied by the coexpression of IGF-like molecules and the soluble binding protein, and that IGF-like molecules are expressed by extraembryonic tissues of mesodermal origin in the early postimplantation mouse embryo. These findings show that IGF-like molecules are expressed in early mammalian development and may act in an autocrine fashion in vivo.

scholarly journals Murine fetal liver macrophages bind developing erythroblasts by a divalent cation-dependent hemagglutinin.

1988 ◽  
Vol 106 (3) ◽  
pp. 649-656 ◽  
Author(s):  
L Morris ◽  
P R Crocker ◽  
S Gordon
Keyword(s):  
Plasma Membrane ◽  
Divalent Cation ◽  
Plasma Membranes ◽  
Fetal Liver ◽  
Divalent Cations ◽  
Membrane Receptors ◽  
Erythroid Cells ◽  
Mammalian Development ◽  
Trypsin Treatment ◽  
Plasma Membrane Receptors

During mammalian development the fetal liver plays an important role in hematopoiesis. Studies with the macrophage (M phi)-specific mAb F4/80 have revealed an extensive network of M phi plasma membranes interspersed between developing erythroid cells in fetal liver. To investigate the interactions between erythroid cells and stromal M phi, we isolated hematopoietic cell clusters from embryonic day-14 murine fetal liver by collagenase digestion and adherence. Clusters of erythroid cells adhered to glass mainly via M phi, 94% of which bound 19 +/- 11 erythroblasts (Eb) per cell. Bound Eb proliferated vigorously on the surface of fetal liver M phi, with little evidence of ingestion. The M phi could be stripped of their associated Eb and the clusters then reconstituted by incubation with Eb in the presence of divalent cations. The interaction required less Ca++ than Mg++, 100 vs. 250 microM for half-maximal binding, and was mediated by a trypsin-sensitive hemagglutinin on the M phi surface. After trypsin treatment fetal liver M phi recovered the ability to bind Eb and this process could be selectively inhibited by cycloheximide. Inhibition tests showed that the Eb receptor differs from known M phi plasma membrane receptors and fetal liver M phi did not bind sheep erythrocytes, a ligand for a distinct M phi hemagglutinin. We propose that fetal liver M phi interact with developing erythroid cells by a novel nonphagocytic surface hemagglutinin which is specific for a ligand found on Eb and not on mature red cells.

scholarly journals Internalization of lectins in neuronal GERL.

1977 ◽  
Vol 73 (1) ◽  
pp. 1-13 ◽  
Author(s):  
N K Gonatas ◽  
S U Kim ◽  
A Stieber ◽  
S Avrameas
Keyword(s):  
Plasma Membrane ◽  
Membrane Receptors ◽  
Dorsal Root Ganglion Neurons ◽  
Cytochemical Study ◽  
Receptor Complexes ◽  
Mouse Dorsal Root Ganglion ◽  
Respiration Inhibitors ◽  
Ricin Agglutinin ◽  
Plasma Membrane Receptors ◽  
Ganglion Neurons

Conjugates of ricin agglutinin and phytohemagglutinin with horseradish peroxidase (HRP) were used for a cytochemical study of internalization of their plasma membrane "receptors" in cultured isolated mouse dorsal root ganglion neurons. Labeling of cells with lectin-HRP was done at 4 degrees C, and internalization was performed at 37 degrees C in a culture medium free of lectin-HRP. 15-20 min after incubation at 37 degrees C, lectin-HRP receptor complexes were seen in vesicles or tubules located near the plasma membrane. After 1-3 h at 37 degrees C, lectin-HRP-receptor complexes accumulated in vesicles and tubules corresponding to acid phosphatase-rich vesicles and tubules (GERL) at the trans aspect of the Golgi apparatus. A few coated vesicles and probably some dense bodies contained HRP after 3-6 h of incubation at 37 degrees C. Soluble HRP was not endocytosed under the conditions of this experiment or when it was present in the incubation medium at 37 degrees C. Internalization of lectin-HRP-receptor conjugates was decreased or inhibited by mitochondrial respiration inhibitors but not by cytochalasin B or colchicine. These studies indicate that lectin-labeled plasma membrane moieties of neurons are endocytosed primarily in elements of GERL.

Sign in / Sign up

Export Citation Format

Share Document