scholarly journals Ligatin from embryonic chick neural retina.

1979 ◽  
Vol 80 (3) ◽  
pp. 642-650 ◽  
Author(s):  
E R Jakoi ◽  
R B Marchase
Keyword(s):  
Cell Surface ◽  
Plasma Membranes ◽  
Protein A ◽  
Neural Retina ◽  
Surface Proteins ◽  
Embryonic Chick ◽  
Cell Surface Proteins ◽  
Rat Ileum ◽  
Discrete Band

Ligatin, a filamentous protein previously found in suckling rat ileum, has been purified from plasma membranes of embryonic chick neural retina. The isolated plasma membranes are covered in part by 4.5-nm filaments that can be released from the membranes by treatment with Ca++. Subsequent dialysis against EGTA followed by sieve chromatography results in purification of the 10,000-dalton ligatin monomer. When labeled either with radioisotopes or with fluorescamine, the monomer is shown to electrophorese as a single discrete band in polyacrylamide gels. However, during standard fixing and staining procedures it diffuses from the gels and thus is not visualized. Ligatin's amino acid composition is distinguished by its high content of polar residues, especially Glx and Asx, and by the presence of phosphorylated serine. Upon re-addition of Ca++, purified ligatin monomers polymerize to form filaments 3 nm in Diam, identical to those formed by purified ileal ligatin. However, in both retina and ileum, the filaments observed on plasma membranes are greater than 3 nm in Diam. In ileum, this enlargement results from ligatin's function as a baseplate for the attachment of another protein, a beta-N-acetylhexosaminidase, to the cell surface. In retina, a corresponding difference in diameter between filaments seen in vivo and those formed from repolymerized ligatin alone and the co-solubilization of other proteins with ligatin suggest that ligatin may also function there as a baseplate for other cell surface proteins. The proteins associated with ligatin in retina differ morphologically from beta-N-acetylhexosaminidase and do not possess this enzymatic activity.

scholarly journals Covalent labeling of cell-surface proteins for in-vivo FRET studies

FEBS Letters ◽  
2006 ◽  
Vol 580 (6) ◽  
pp. 1654-1658 ◽  
Author(s):  
Bruno H. Meyer ◽  
Karen L. Martinez ◽  
Jean-Manuel Segura ◽  
Pedro Pascoal ◽  
Ruud Hovius ◽  
...  
Keyword(s):  
Cell Surface ◽  
Surface Proteins ◽  
Covalent Labeling ◽  
Cell Surface Proteins

scholarly journals Regulation of agr-Dependent Virulence Genes in Staphylococcus aureus by RNAIII from Coagulase-Negative Staphylococci

1998 ◽  
Vol 180 (12) ◽  
pp. 3181-3186 ◽  
Author(s):  
Karin Tegmark ◽  
Eva Morfeldt ◽  
Staffan Arvidson
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Surface ◽  
Serine Protease ◽  
Protein A ◽  
Surface Proteins ◽  
Open Reading Frames ◽  
Alpha Toxin ◽  
Coagulase Negative Staphylococci ◽  
Cell Surface Proteins ◽  
Genes Encoding

ABSTRACT Many of the genes coding for extracellular toxins, enzymes, and cell surface proteins in Staphylococcus aureus are regulated by a 510-nucleotide (nt) RNA molecule, RNAIII. Transcription of genes encoding secreted toxins and enzymes, includinghla (alpha-toxin), saeB (enterotoxin B),tst (toxic shock syndrome toxin 1), and ssp(serine protease), is stimulated, while transcription of genes encoding cell surface proteins, like spa (protein A) andfnb (fibronectin binding proteins), is repressed. Besides being a regulator, RNAIII is also an mRNA coding for staphylococcal delta-lysin. We have identified RNAIII homologs in three different coagulase-negative staphylococci (CoNS), i.e., Staphylococcus epidermidis, Staphylococcus simulans, andStaphylococcus warneri. RNAIII from these CoNS turned out to be very similar to that of S. aureus and contained open reading frames encoding delta-lysin homologs. Though a number of big insertions and/or deletions have occurred, mainly in the 5′ half of the molecules, the sequences show a high degree of identity, especially in the first 50 and last 150 nt. The CoNS RNAIII had the ability to completely repress transcription of protein A in an RNAIII-deficientS. aureus mutant and the ability to stimulate transcription of the alpha-toxin and serine protease genes. However, the stimulatory effect was impaired compared to that of S. aureus RNAIII, suggesting that these regulatory functions are independent. By creating S. epidermidis-S. aureus RNAIII hybrids, we could also show that both the 5′ and 3′ halves of the RNAIII molecule are involved in the transcriptional regulation of alpha-toxin and serine protease mRNAs in S. aureus.

Isolation of Glomeruli and In Vivo Labeling of Glomerular Cell Surface Proteins

10.3791/58542 ◽  
2019 ◽  
Author(s):  
Eva Königshausen ◽  
Sebastian A. Potthoff ◽  
Raphael Haase ◽  
Catherine Meyer-Schwesinger ◽  
Ernest Kaufmann ◽  
...  
Keyword(s):  
Cell Surface ◽  
Surface Proteins ◽  
Cell Surface Proteins ◽  
Glomerular Cell

scholarly journals Endocytosis of liposomes bound to cell surface proteins measured by flow cytofluorometry

1983 ◽  
Vol 214 (1) ◽  
pp. 189-194 ◽  
Author(s):  
A Truneh ◽  
Z Mishal ◽  
J Barbet ◽  
P Machy ◽  
L D Leserman
Keyword(s):  
Flow Cytometry ◽  
Cell Surface ◽  
Membrane Surface ◽  
Protein A ◽  
Surface Proteins ◽  
Cellular Receptor ◽  
Cell Surface Proteins ◽  
Flow Cytofluorometry ◽  
High Concentrations ◽  
A New Technique

A new technique for the quantification of cellular receptor-mediated endocytosis has been developed based on the analysis by flow cytometry of ligand-bearing liposomes containing the fluorochrome carboxyfluorescein. Carboxyfluorescein encapsulated at high concentrations in protein A-bearing liposomes is self-quenched. Binding and internalization of such liposomes by cells via antibodies directed towards membrane surface determinants results in the release of the liposome-encapsulated carboxyfluorescein into the cytoplasm causing an increase in cell-associated fluorescence. This increase can be quantified on a flow cytofluorometer.

Disruption of pioneer growth cone guidance in vivo by removal of glycosyl-phosphatidylinositol-anchored cell surface proteins

Development ◽  
1992 ◽  
Vol 114 (2) ◽  
pp. 507-519 ◽  
Author(s):  
W.S. Chang ◽  
K. Serikawa ◽  
K. Allen ◽  
D. Bentley
Keyword(s):  
Cell Surface ◽  
Growth Cone ◽  
Growth Cones ◽  
Surface Proteins ◽  
Limb Bud ◽  
Cell Surface Proteins ◽  
Glycosyl Phosphatidylinositol ◽  
Stage Of Development ◽  
Growth Cone Guidance

Cell surface proteins anchored to membranes via covalently attached glycosyl-phosphatidylinositol (GPI) have been implicated in neuronal adhesion, promotion of neurite outgrowth and directed cell migration. Treatment of grasshopper embryos with bacterial phosphatidylinositol-specific phospholipase C (PI-PLC), an enzyme that cleaves the GPI anchor, often induced disruptions in the highly stereotyped migrations of peripheral pioneer growth cones and afferent neuron cell bodies. In distal limb regions of embryos treated with PI-PLC at early stages of pioneer axon outgrowth, growth cones lost their proximal orientation toward the central nervous system (CNS) and turned distally. Pioneer growth cones in treated limbs also failed to make a characteristic ventral turn along the trochanter-coxa (Tr-Cx) segment boundary, and instead continued to grow proximally across the boundary. Treatment at an earlier stage of development caused pre-axonogenesis Cx1 neurons to abandon their normal circumferential migration and reorient toward the CNS. None of these abnormal phenotypes were observed in limbs of untreated embryos or embryos exposed to other phospholipases that do not release GPI-anchored proteins. Incubation of embryos with PI-PLC effectively removed immunoreactivity for fasciclin I, a GPI-anchored protein expressed on a subset of neuronal surfaces. These results suggest that cell surface GPI-anchored proteins are involved in pioneer growth cone guidance and in pre-axonogenesis migration of neurons in the grasshopper limb bud in vivo.

scholarly journals Discriminating gene expression profiles of memory B cell subpopulations

2008 ◽  
Vol 205 (8) ◽  
pp. 1807-1817 ◽  
Author(s):  
Götz R.A. Ehrhardt ◽  
Atsushi Hijikata ◽  
Hiroshi Kitamura ◽  
Osamu Ohara ◽  
Ji-Yang Wang ◽  
...  
Keyword(s):  
Transcription Factors ◽  
Cell Surface ◽  
Intracellular Signaling ◽  
Expression Profiles ◽  
Surface Proteins ◽  
Epithelial Tissue ◽  
Cell Surface Proteins ◽  
Cell Subpopulations

Morphologically and functionally distinct subpopulations of human memory B (BMem) cells are identifiable by either their expression of CD27 or Fc receptor–like 4 (FCRL4), an immunoglobulin domain containing a receptor with strong inhibitory potential. We have conducted comparative transcriptome and proteome analyses of FCRL4+ and FCRL4− BMem cells and found that these two subsets have very distinctive expression profiles for genes encoding transcription factors, cell-surface proteins, intracellular signaling molecules, and modifiers of the cell-cycle status. Among the differentially expressed transcription factors, runt-related transcription factor 1 (RUNX1) transcript levels were up-regulated in FCRL4− cells, whereas RUNX2 transcripts were preferentially detected in FCRL4+ cells. In vitro evidence for FCRL4 promoter responsiveness and in vivo promoter occupancy suggested that RUNX transcription factors are involved in the generation of these BMem cell subpopulations. A distinctive signature profile was defined for the FCRL4+ BMem cells by their expression of CD11c, receptor activator for nuclear factor κB ligand, and FAS cell-surface proteins, in combination with increased levels of SOX5, RUNX2, DLL1, and AICDA expression. We conclude that this recently identified subpopulation of BMem cells, which normally resides in epithelial tissue-based niches, may serve a unique role in mucosal defense and, conversely, as a target for neoplastic transformation events.

scholarly journals Membrane protein redistribution during differentiation of cultured human erythroleukemic cells.

1981 ◽  
Vol 1 (12) ◽  
pp. 1150-1162 ◽  
Author(s):  
R C Hunt ◽  
L M Marshall
Keyword(s):  
Cell Surface ◽  
K562 Cells ◽  
Erythroid Differentiation ◽  
Surface Proteins ◽  
Cell Surface Proteins ◽  
Mature Erythrocyte ◽  
Transmission Electron ◽  
Immune Precipitation

Human erythroleukemic (K562) cells differentiate along the erythroid differentiation pathway in vitro when 0.05 mM hemin is included in the growth medium. In the presence of the inducer the cells continue to proliferate and, after a delay of 24 to 48 h, start to synthesize hemoglobin. However, during differentiation, no changes in the major cell surface proteins were detected using lactoperoxidase-catalyzed iodination, and no change in the synthesis of spectrin, the major cytoskeletal protein of the mature erythrocyte, was detected by specific immune precipitation. Despite this absence of major changes in cell surface proteins, profound changes take place in the organization of the cell membranes. A process similar but not identical to the enucleation observed in erythroid differentiation in vivo occurs in which a smooth-surfaced cell, about 10 micrometers in diameter, is divided from the nucleus-containing part of the cell. With the exception of ribosomes, these reticulocyte-like cells contain no organelles when examined by transmission electron microscopy, but contain much of the parent cell's hemoglobin, spectrin, and glycophorin.

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