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Journal ArticleDOI

Protein and cell membrane iodinations with a sparingly soluble chloroamide, 1,3,4,6-tetrachloro-3a,6a-diphrenylglycoluril.

28 Feb 1978-Biochemical and Biophysical Research Communications (Biochem Biophys Res Commun)-Vol. 80, Iss: 4, pp 849-857
TL;DR: The stability and sparing solubility of this chloroglycoluril in water can account for the minimal damage to proteins and living cells observed in these iodinations and allow for elimination of the reduction step employed at the close of iodinations with soluble chloroamides such as chloramine-T.
About: This article is published in Biochemical and Biophysical Research Communications.The article was published on 1978-02-28. It has received 4494 citations till now. The article focuses on the topics: Reagent.
Citations
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Journal ArticleDOI
30 Aug 1985-Science
TL;DR: The data suggest that cachectin/TNF is one of the principal mediators of the lethal effect of endotoxin, and this effect was dose-dependent and was most effective when the antiserum was administered prior to the injection of the endotoxin.
Abstract: A highly specific polyclonal rabbit antiserum directed against murine cachectin/tumor necrosis factor (TNF) was prepared. When BALB/c mice were passively immunized with the antiserum or with purified immune globulin, they were protected against the lethal effect of the endotoxin lipopolysaccharide produced by Escherichia coli. The prophylactic effect was dose-dependent and was most effective when the antiserum was administered prior to the injection of the endotoxin. Antiserum to cachectin/TNF did not mitigate the febrile response of endotoxin-treated animals, and very high doses of endotoxin could overcome the protective effect. The median lethal dose of endotoxin in mice pretreated with 50 microliters of the specific antiserum was approximately 2.5 times greater the median lethal dose for controls given nonimmune serum. The data suggest that cachectin/TNF is one of the principal mediators of the lethal effect of endotoxin.

2,320 citations

Journal ArticleDOI
21 Jul 1989-Science
TL;DR: Histological thin sections of the regressing tumor showed that anti-APO-1 was able to induce apoptosis in vivo, suggesting induction of apoptosis as a consequence of a signal mediated through cell surface molecules like APO- 1 may be a useful therapeutic approach in treatment of malignancy.
Abstract: To characterize cell surface molecules involved in control of growth of malignant lymphocytes, monoclonal antibodies were raised against the human B lymphoblast cell line SKW6.4. One monoclonal antibody, anti-APO-1, reacted with a 52-kilodalton antigen (APO-1) on a set of activated human lymphocytes, on malignant human lymphocyte lines, and on some patient-derived leukemic cells. Nanogram quantities of anti-APO-1 completely blocked proliferation of cells bearing APO-1 in vitro in a manner characteristic of a process called programmed cell death or apoptosis. Cell death was preceded by changes in cell morphology and fragmentation of DNA. This process was distinct from antibody- and complement-dependent cell lysis and was mediated by the antibody alone. A single intravenous injection of anti-APO-1 into nu/nu mice carrying a xenotransplant of a human B cell tumor induced regression of this tumor within a few days. Histological thin sections of the regressing tumor showed that anti-APO-1 was able to induce apoptosis in vivo. Thus, induction of apoptosis as a consequence of a signal mediated through cell surface molecules like APO-1 may be a useful therapeutic approach in treatment of malignancy.

1,823 citations

Journal ArticleDOI
TL;DR: A novel role for rab11 in controlling traffic through the recycling endosome is suggested after functional studies showed that the early steps of uptake and recycling for transferrin were not affected by overexpression of rab11 proteins.
Abstract: Small GTPases of the rab family are crucial elements of the machinery that controls membrane traffic. In the present study, we examined the distribution and function of rab11. Rab11 was shown by confocal immunofluorescence microscopy and EM to colocalize with internalized transferrin in the pericentriolar recycling compartment of CHO and BHK cells. Expression of rab11 mutants that are preferentially in the GTP- or GDP-bound state caused opposite effects on the distribution of transferrin-containing elements; rab11-GTP expression caused accumulation of labeled elements in the perinuclear area of the cell, whereas rab11-GDP caused a dispersion of the transferrin labeling. Functional studies showed that the early steps of uptake and recycling for transferrin were not affected by overexpression of rab11 proteins. However, recycling from the later recycling endosome was inhibited in cells overexpressing the rab11-GDP mutant. Rab5, which regulates early endocytic trafficking, acted before rab11 in the transferrin-recycling pathway as expression of rab5-GTP prevented transport to the rab11-positive recycling endosome. These results suggest a novel role for rab11 in controlling traffic through the recycling endosome.

1,341 citations


Cites methods from "Protein and cell membrane iodinatio..."

  • ...Iron-saturated human transferrin (Sigma Immunochemicals) was labeled with lzsI to a specific activity of 3 × 107 cpm/~g using Iodogen (Fraker and Speck, 1978)....

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Journal ArticleDOI
TL;DR: A role for integrin- mediated tyrosine phosphorylation in the organization of the cytoskeleton as cells adhere to the extracellular matrix is suggested.
Abstract: Cells in culture reveal high levels of protein tyrosine phosphorylation in their focal adhesions, the regions where cells adhere to the underlying substratum. We have examined the tyrosine phosphorylation of proteins in response to plating cells on extracellular matrix substrata. Rat embryo fibroblasts, mouse Balb/c 3T3, and NIH 3T3 cells plated on fibronectin-coated surfaces revealed elevated phosphotyrosine levels in a cluster of proteins between 115 and 130 kD. This increase in tyrosine phosphorylation was also seen when rat embryo fibroblasts were plated on laminin or vitronectin, but not on polylysine or on uncoated plastic. Integrin mediation of this effect was suggested by finding the same pattern of elevated tyrosine phosphorylation in cells plated on the cell-binding fragment of fibronectin and in cells plated on a synthetic polymer containing multiple RGD sequences. We have identified one of the proteins of the 115-130-kD cluster as pp125FAK, a tyrosine kinase recently localized in focal adhesions (Schaller, M. D., C. A. Borgman, B. S. Cobb, R. R. Vines, A. B. Reynolds, and J. T. Parsons. 1992. Proc. Natl. Acad. Sci. USA. 89:5192). A second protein that becomes tyrosine phosphorylated in response to extracellular matrix adhesion is identified as paxillin, a 70-kD protein previously localized to focal adhesions. Treatment of cells with the tyrosine kinase inhibitor herbimycin A diminished the adhesion-induced tyrosine phosphorylation of these proteins and inhibited the formation of focal adhesions and stress fibers. These results suggest a role for integrin-mediated tyrosine phosphorylation in the organization of the cytoskeleton as cells adhere to the extracellular matrix.

1,313 citations

Journal ArticleDOI
TL;DR: Results indicate that Iodogen can be used for a wide range of proteins and peptides, can permit theoretical iodine incorporation with minimal oxidation damage, and can produce tracer stable for up to 3 months.

1,096 citations

References
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Journal Article
TL;DR: Procedures are described for measuring protein in solution or after precipitation with acids or other agents, and for the determination of as little as 0.2 gamma of protein.

289,852 citations

Journal ArticleDOI
24 Jun 1967-Nature
TL;DR: Biologically active proteins and polypeptides can be coupled by various means to cellulose, starch and cross-linked polysaccharide gels such as ‘Sephadex’.
Abstract: Biologically active proteins and polypeptides can be coupled by various means to cellulose, starch and cross-linked polysaccharide gels such as ‘Sephadex’. The use of cyanogen halides for this purpose gives a high yield of bound polypeptide or protein which retains a substantial part of its activity.

1,997 citations

Journal ArticleDOI
TL;DR: An enzymatic iodination procedure utilizing lactoperoxidase, radioactive iodide, and hydrogen peroxide generated by a glucose oxidase-glucose system has been described and utilized for a study of the red cell membrane.
Abstract: An enzymatic iodination procedure utilizing lactoperoxidase (LPO), radioactive iodide, and hydrogen peroxide generated by a glucose oxidase-glucose system has been described and utilized for a study of the red cell membrane. 97% of the incorporated isotope is in the erythrocyte ghost and 3% is associated with hemoglobin. No significant labeling of the red cell membrane occurs in the absence of LPO or by the deletion of any of the other reagents. A 6 million-fold excess of chloride ions inhibits iodination by no more than 50%. Incorporation of up to 1 x 106 iodide atoms into a single erythrocyte membrane results in no significant cell lysis. The incorporated label is exclusively in tyrosine residues as monoiodotyrosine. 10–15% of the trichloroacetic acid-precipitable radioactivity can be extracted with lipid solvents but is present as either labeled protein or 125I. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of solubilized membrane proteins reveals only two labeled protein bands out of the 15 present, and the presence of 50-1 x 106 iodide atoms per ghost does not alter this pattern. Component a has a molecular weight of 110,000, is carbohydrate poor, and represents 40% of the total label. Component b has an apparent molecular weight of 74,000, contains all of the demonstrable sialic acid, and accounts for 60% of the total label. Trypsinization of iodinated, intact red cells results in the disappearance of only component b, the appearance of labeled glycopeptides in the medium, and the absence of smaller, labeled peptides remaining in the membrane. Pronase treatment hydrolyzes component b in a similar fashion, but also cleaves component a to a 72,000 mol wt peptide which is retained in the membrane. A combination of protease treatment and double labeling with 125I and 131I does not reveal the appearance of previously unexposed proteins.

660 citations

Journal ArticleDOI
TL;DR: The enzymatic iodination technique has been utilized in a study of the externally disposed membrane proteins of the mouse L cell with no loss of cell viability under the conditions employed, less than 3% lipid labeling, and more than 90% of the labeled species identifiable as monoiodotyrosine.
Abstract: The enzymatic iodination technique has been utilized in a study of the externally disposed membrane proteins of the mouse L cell. Iodination of cells in suspension results in lactoperoxidase-specific iodide incorporation with no loss of cell viability under the conditions employed, less than 3% lipid labeling, and more than 90% of the labeled species identifiable as monoiodotyrosine. 90% of the incorporated label is localized to the cell surface by electron microscope autoradiography, with 5-10% in the centrosphere region and postulated to represent pinocytic vesicles. Sodium dodecylsulfate-polyacrylamide gels of solubilized L-cell proteins reveals five to six labeled peaks ranging from 50,000 to 200,000 daltons. Increased resolution by use of gradient slab gels reveals 15-20 radioactive bands. Over 60% of the label resides in approximately nine polypeptides of 80,000 to 150,000 daltons. Various controls indicate that the labeling pattern reflects endogenous membrane proteins, not serum components. The incorporated 125-I, cholesterol, and one plasma membrane enzyme marker, alkaline phosphodiesterase I, are purified in parallel when plasma membranes are isolated from intact, iodinated L cells. The labeled components present in a plasma membrane-rich fraction from iodinated cells are identical to those of the total cell, with a 10- to 20-fold enrichment in specific activity of each radioactive peak in the membrane.

330 citations