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Eduardo Lissi - One of the best experts on this subject based on the ideXlab platform.
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peroxynitrite oxidizes erythrocyte membrane band 3 protein and diminishes its Anion Transport capacity
Free Radical Research, 2007Co-Authors: Gloria Celedon, Gustavo González, José Pino, Eduardo LissiAbstract:We describe an altered membrane band 3 protein-mediated Anion Transport in erythrocytes exposed to peroxynitrite, and relate the loss of Anion Transport to cell damage and to band 3 oxidative modifications. We found that peroxynitrite down-regulate Anion Transport in a dose dependent relation (100–300 μmoles/l). Hemoglobin oxidation was found at all peroxynitrite concentrations studied. A dose-dependent band 3 protein crosslinking and tyrosine nitration were also observed. Band 3 protein modifications were concomitant with a decrease in Transport activity. ( − )-Epicatechin avoids band 3 protein nitration but barely affects its Transport capacity, suggesting that both processes are unrelated. N-acetyl cysteine partially reverted the loss of band 3 Transport capacity. It is concluded that peroxynitrite promotes a decrease in Anion Transport that is partially due to the reversible oxidation of band 3 cysteine residues. Additionally, band 3 tyrosine nitration seems not to be relevant for the loss of its anio...
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peroxyl oxidized erythrocyte membrane band 3 protein with Anion Transport capacity is degraded by membrane bound proteinase
Free Radical Research, 2004Co-Authors: Gloria Celedon, Gustavo González, Veronica Ferrer, Eduardo LissiAbstract:Human red blood cells Anion exchange protein (band 3) exposed to peroxyl radicals produced by thermolysis of 2,2'-azo-bis(2-amidinopropane) (AAPH) is degraded by proteinases that prevent accumulation of oxidatively damaged proteins. To assess whether this degradation affects Anion Transport capacity we used the Anionic fluorescent probe 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-y) amino] ethanosulfonate (NBD-taurine). A decrease of band 3 function was observed after exposure to peroxyl radicals. In the presence of proteinase inhibitors the decrement of Anion Transport through band 3 was smaller indicating that removal achieved by proteinases includes oxidized band 3 which still retain Transport ability. Proteinases recognize band 3 aggregates produced by peroxyl radicals as was evaluated by immunoblotting. It is concluded that decrease of band 3 Transport capacity may result from a direct protein oxidation and from its degradation by proteinases and that band 3 aggregates removal may prevent macrophage recognition of the senescent condition which would lead to cell disposal.
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peroxyl oxidized erythrocyte membrane band 3 protein with Anion Transport capacity is degraded by membrane bound proteinase
Free Radical Research, 2004Co-Authors: Gloria Celedon, Gustavo González, Veronica Ferrer, Eduardo LissiAbstract:Human red blood cells Anion exchange protein (band 3) exposed to peroxyl radicals produced by thermolysis of 2,2′-azo-bis(2-amidinopropane) (AAPH) is degraded by proteinases that prevent accumulation of oxidatively damaged proteins. To assess whether this degradation affects Anion Transport capacity we used the Anionic fluorescent probe 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-y) amino] ethanosulfonate (NBD-taurine). A decrease of band 3 function was observed after exposure to peroxyl radicals. In the presence of proteinase inhibitors the decrement of Anion Transport through band 3 was smaller indicating that removal achieved by proteinases includes oxidized band 3 which still retain Transport ability. Proteinases recognize band 3 aggregates produced by peroxyl radicals as was evaluated by immunoblotting. It is concluded that decrease of band 3 Transport capacity may result from a direct protein oxidation and from its degradation by proteinases and that band 3 aggregates removal may prevent macrophage recogni...
H Passow - One of the best experts on this subject based on the ideXlab platform.
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three different actions of phenylglyoxal on band 3 protein mediated Anion Transport across the red blood cell membrane
Biochimica et Biophysica Acta, 1997Co-Authors: E M Gartner, H Fasold, Barbara Legrum, K Liebold, H PassowAbstract:Abstract Phenylglyoxalation of the red blood cell membrane leads to three superimposed effects on band 3 protein-mediated Anion equilibrium exchange as measured by means of radiosulfate: (1) a shift of the curve relating Transport activity to pH towards lower pH values, possibly in combination with an increase of the maximal Transport activity. This is accompanied by effect (2), the abolishment of a chloride-stimulated component of Anion Transport seen at low pH values. Effect (3) consists of inhibition of Anion equilibrium exchange. Effect (1) prevails when phenylglyoxalation is performed at low concentrations of PG and low pH, while effect (3) predominates when exposure to PG is executed at high pH and high concentration of PG. Effect (1) is associated with a decrease of the K i values for inhibition and binding of the reversibly acting stilbene disulfonates DNDS and DBDS. The inhibition observed as a consequence of effect (3) is linearly related to a decrease of the capacity of band 3 to combine with the stilbene disulfonate DBDS. The results are interpreted on the assumption that PG is capable of reacting with two or possibly three distinct binding sites in band 3. Reaction with one of them leads to effect (1) and, perhaps, to effect (2); reaction with the other to effect (3). The latter is possibly due to modification of Arg 730, which is homologous to Arg 748 in mouse band 3. Site-directed mutagenesis of this arginine residue showed that it is required for band 3-mediated Anion Transport.
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Anion Transport function of mouse erythroid band 3 protein ae1 does not require acylation of cysteine residue 861
Biochimica et Biophysica Acta, 1994Co-Authors: Dongchon Kang, Doris Karbach, H PassowAbstract:Abstract Cys-861 of mouse band 3 is equivalent to Cys-843 of human band 3, the only acylated cysteine residue in the Anion exchanger AE1 of the red blood cell (Hamasaki et al. (1992) Progress Cell Res. 2, 65–71). Mutation of Cys-861 to serine or methionine caused no significant changes of band 3-mediated Anion exchange as measured after expression of the appropriate cRNAs in Xenopus oocytes. Susceptibility to inhibition of Transport by 4,4′-dinitrostilbene-2,2′-disulfonate and PCMBS was not affected. We conclude that palmitoylation is not an absolute requirement for the successful execution the Anion Transport function by the hydrophobic domain of band 3 in the plasma membrane.
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mediation of inorganic Anion Transport by the hydrophobic domain of mouse erythroid band 3 protein expressed in oocytes of xenopus laevis
Biochimica et Biophysica Acta, 1992Co-Authors: Sigrid Lepke, Anja Becker, H PassowAbstract:A cDNA clone of the mouse crythroid band 3 protein encoding the 556 amino acid residues of the hydrophobic domain from Thr-374 to the C-terminal Val-929 is shown by immunoprecipitation to be expressed in Xenopus oocytes. Measurements of 36Cl− efflux indicate that the translation product mediates Cl− Transport, which is inhibitable reversibly by DNDS or H2DIDS, specific inhibitors of band 3-mediated Transport. The apparent K1 values are 3.6 μM and 0.094 μM, respectively, and hence similar to those found in the wild type band 3-mediated Anion Transport. The rapid reversible inhibition by H2DIDS slowly changes to irreversible inhibition. The rate of change increases with increasing pH, again similar as to the wild-type band 3. It is concluded that the hydrophobic domain of band 3 is capable of executing Anion Transport essentially similar to the full-length band 3, although minor differences with respect to Transport and inhibition kinetics cannot be ruled out.
Gloria Celedon - One of the best experts on this subject based on the ideXlab platform.
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peroxynitrite oxidizes erythrocyte membrane band 3 protein and diminishes its Anion Transport capacity
Free Radical Research, 2007Co-Authors: Gloria Celedon, Gustavo González, José Pino, Eduardo LissiAbstract:We describe an altered membrane band 3 protein-mediated Anion Transport in erythrocytes exposed to peroxynitrite, and relate the loss of Anion Transport to cell damage and to band 3 oxidative modifications. We found that peroxynitrite down-regulate Anion Transport in a dose dependent relation (100–300 μmoles/l). Hemoglobin oxidation was found at all peroxynitrite concentrations studied. A dose-dependent band 3 protein crosslinking and tyrosine nitration were also observed. Band 3 protein modifications were concomitant with a decrease in Transport activity. ( − )-Epicatechin avoids band 3 protein nitration but barely affects its Transport capacity, suggesting that both processes are unrelated. N-acetyl cysteine partially reverted the loss of band 3 Transport capacity. It is concluded that peroxynitrite promotes a decrease in Anion Transport that is partially due to the reversible oxidation of band 3 cysteine residues. Additionally, band 3 tyrosine nitration seems not to be relevant for the loss of its anio...
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peroxyl oxidized erythrocyte membrane band 3 protein with Anion Transport capacity is degraded by membrane bound proteinase
Free Radical Research, 2004Co-Authors: Gloria Celedon, Gustavo González, Veronica Ferrer, Eduardo LissiAbstract:Human red blood cells Anion exchange protein (band 3) exposed to peroxyl radicals produced by thermolysis of 2,2'-azo-bis(2-amidinopropane) (AAPH) is degraded by proteinases that prevent accumulation of oxidatively damaged proteins. To assess whether this degradation affects Anion Transport capacity we used the Anionic fluorescent probe 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-y) amino] ethanosulfonate (NBD-taurine). A decrease of band 3 function was observed after exposure to peroxyl radicals. In the presence of proteinase inhibitors the decrement of Anion Transport through band 3 was smaller indicating that removal achieved by proteinases includes oxidized band 3 which still retain Transport ability. Proteinases recognize band 3 aggregates produced by peroxyl radicals as was evaluated by immunoblotting. It is concluded that decrease of band 3 Transport capacity may result from a direct protein oxidation and from its degradation by proteinases and that band 3 aggregates removal may prevent macrophage recognition of the senescent condition which would lead to cell disposal.
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peroxyl oxidized erythrocyte membrane band 3 protein with Anion Transport capacity is degraded by membrane bound proteinase
Free Radical Research, 2004Co-Authors: Gloria Celedon, Gustavo González, Veronica Ferrer, Eduardo LissiAbstract:Human red blood cells Anion exchange protein (band 3) exposed to peroxyl radicals produced by thermolysis of 2,2′-azo-bis(2-amidinopropane) (AAPH) is degraded by proteinases that prevent accumulation of oxidatively damaged proteins. To assess whether this degradation affects Anion Transport capacity we used the Anionic fluorescent probe 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-y) amino] ethanosulfonate (NBD-taurine). A decrease of band 3 function was observed after exposure to peroxyl radicals. In the presence of proteinase inhibitors the decrement of Anion Transport through band 3 was smaller indicating that removal achieved by proteinases includes oxidized band 3 which still retain Transport ability. Proteinases recognize band 3 aggregates produced by peroxyl radicals as was evaluated by immunoblotting. It is concluded that decrease of band 3 Transport capacity may result from a direct protein oxidation and from its degradation by proteinases and that band 3 aggregates removal may prevent macrophage recogni...
Reinhart A. F. Reithmeier - One of the best experts on this subject based on the ideXlab platform.
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two dimensional structure of the membrane domain of human band 3 the Anion Transport protein of the erythrocyte membrane
The EMBO Journal, 1993Co-Authors: Daneng Wang, V E Sarabia, Werner Kuhlbrandt, Reinhart A. F. ReithmeierAbstract:Abstract The membrane domain of human erythrocyte Band 3 protein (M(r) 52,000) was reconstituted with lipids into two-dimensional crystals in the form of sheets or tubes. Crystalline sheets were monolayers with six-fold symmetry (layer group p6, a = b = 170 A, gamma = 60 degrees), whereas the symmetry of the tubular crystals was p2 (a = 104 A, b = 63 A, gamma = 104 degrees). Electron image analysis of negatively stained specimens yielded projection maps of the protein at 20 A resolution. Maps derived from both crystal forms show that the membrane domain is a dimer of two monomers related by two-fold symmetry, with each monomer consisting of three subdomains. In the dimer, two subdomains of each monomer form a roughly rectangular core (40 x 50 A in projection), surrounding a central depression. The third subdomain of the monomer measures approximately 15 x 25 A in projection and appears to be connected to the other two by a flexible link. We propose that the central depression may represent the channel for Anion Transport while the third subdomain appears not to be directly involved in channel formation.
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enzymatic deglycosylation of human band 3 the Anion Transport protein of the erythrocyte membrane effect on protein structure and Transport properties
Journal of Biological Chemistry, 1992Co-Authors: Joseph R Casey, Charles A Pirraglia, Reinhart A. F. ReithmeierAbstract:Abstract The structural and functional roles of the single asparagine (N)-linked oligosaccharide chain of Band 3 (AE1), the Anion Transport protein of the human erythrocyte membrane, were examined. Purified Band 3 (M(r) = 95,000) in 0.1% octaethylene glycol mono n-dodecyl ether (C12E8) detergent solution was deglycosylated using N-glycosidase F. This treatment sharpened the protein band on sodium dodecyl sulfate gel electrophoresis and decreased its apparent molecular weight by 5,000. The purified membrane domain could be deglycosylated under similar conditions, causing a shift from a broad band centered at 55 kDa to a sharp 46-kDa band. Band 3 was shown to bind tomato lectin, and loss of lectin binding on blots provided a sensitive assay for deglycosylation. Carbohydrate analysis revealed that greater than 80% of the oligosaccharide could be removed from Band 3 by N-glycosidase F digestion. The deglycosylated protein maintained its dimeric structure and level of detergent binding but had a smaller Stokes radius (RS = 72 A) than native Band 3 (RS = 75 A). The Stokes radius of the membrane domain (RS = 60 A) also decreased upon deglycosylation (RS = 58 A). Circular dichroism studies showed that deglycosylation did not change the secondary structure of Band 3 or the membrane domain. The sensitivity of Band 3 or the membrane domain to proteolytic digestion by trypsin or proteinase K was also unaffected by deglycosylation. The deglycosylated protein aggregated more rapidly and was much more readily precipitable by ammonium sulfate. The deglycosylated protein bound the Anion Transport inhibitor 4-benzamido-4'-amino-stilbene-2,2'-disulfonate with the same affinity (Kd = 1 microM) as the native protein. Transport studies using reconstituted Band 3 and resealed ghosts showed that deglycosylated Band 3 retained its ability to Transport Anions. We conclude that removal of the oligosaccharide chain from Band 3 and any resultant structural changes had no effect on the Transport function of this protein.
Gustavo González - One of the best experts on this subject based on the ideXlab platform.
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peroxynitrite oxidizes erythrocyte membrane band 3 protein and diminishes its Anion Transport capacity
Free Radical Research, 2007Co-Authors: Gloria Celedon, Gustavo González, José Pino, Eduardo LissiAbstract:We describe an altered membrane band 3 protein-mediated Anion Transport in erythrocytes exposed to peroxynitrite, and relate the loss of Anion Transport to cell damage and to band 3 oxidative modifications. We found that peroxynitrite down-regulate Anion Transport in a dose dependent relation (100–300 μmoles/l). Hemoglobin oxidation was found at all peroxynitrite concentrations studied. A dose-dependent band 3 protein crosslinking and tyrosine nitration were also observed. Band 3 protein modifications were concomitant with a decrease in Transport activity. ( − )-Epicatechin avoids band 3 protein nitration but barely affects its Transport capacity, suggesting that both processes are unrelated. N-acetyl cysteine partially reverted the loss of band 3 Transport capacity. It is concluded that peroxynitrite promotes a decrease in Anion Transport that is partially due to the reversible oxidation of band 3 cysteine residues. Additionally, band 3 tyrosine nitration seems not to be relevant for the loss of its anio...
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peroxyl oxidized erythrocyte membrane band 3 protein with Anion Transport capacity is degraded by membrane bound proteinase
Free Radical Research, 2004Co-Authors: Gloria Celedon, Gustavo González, Veronica Ferrer, Eduardo LissiAbstract:Human red blood cells Anion exchange protein (band 3) exposed to peroxyl radicals produced by thermolysis of 2,2'-azo-bis(2-amidinopropane) (AAPH) is degraded by proteinases that prevent accumulation of oxidatively damaged proteins. To assess whether this degradation affects Anion Transport capacity we used the Anionic fluorescent probe 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-y) amino] ethanosulfonate (NBD-taurine). A decrease of band 3 function was observed after exposure to peroxyl radicals. In the presence of proteinase inhibitors the decrement of Anion Transport through band 3 was smaller indicating that removal achieved by proteinases includes oxidized band 3 which still retain Transport ability. Proteinases recognize band 3 aggregates produced by peroxyl radicals as was evaluated by immunoblotting. It is concluded that decrease of band 3 Transport capacity may result from a direct protein oxidation and from its degradation by proteinases and that band 3 aggregates removal may prevent macrophage recognition of the senescent condition which would lead to cell disposal.
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peroxyl oxidized erythrocyte membrane band 3 protein with Anion Transport capacity is degraded by membrane bound proteinase
Free Radical Research, 2004Co-Authors: Gloria Celedon, Gustavo González, Veronica Ferrer, Eduardo LissiAbstract:Human red blood cells Anion exchange protein (band 3) exposed to peroxyl radicals produced by thermolysis of 2,2′-azo-bis(2-amidinopropane) (AAPH) is degraded by proteinases that prevent accumulation of oxidatively damaged proteins. To assess whether this degradation affects Anion Transport capacity we used the Anionic fluorescent probe 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-y) amino] ethanosulfonate (NBD-taurine). A decrease of band 3 function was observed after exposure to peroxyl radicals. In the presence of proteinase inhibitors the decrement of Anion Transport through band 3 was smaller indicating that removal achieved by proteinases includes oxidized band 3 which still retain Transport ability. Proteinases recognize band 3 aggregates produced by peroxyl radicals as was evaluated by immunoblotting. It is concluded that decrease of band 3 Transport capacity may result from a direct protein oxidation and from its degradation by proteinases and that band 3 aggregates removal may prevent macrophage recogni...