Red blood cell band 3. Lysine 539 and lysine 851 react with the same H2DIDS (4,4'-diisothiocyanodihydrostilbene-2,2'-disulfonic acid) molecule.
AuthorsOkubo K, Kang D, Hamasaki N, Jennings ML
JournalJ Biol Chem
PubMed ID8294441
The band 3 protein of the red blood cell membrane catalyzes anion exchange that is inhibited by the stilbenedisulfonate derivative H2DIDS (4,4'-diisothiocyanodihydrostilbene-2,2'-disulfonic acid). There is one H2DIDS binding site per 95,000-Da band 3 polypeptide. The single bound H2DIDS molecule can react covalently with 2 different lysine residues. The 2 lysines ... More
Oriented reconstitution of red cell membrane proteins and assessment of their transmembrane disposition by immunoquenching of fluorescence.
AuthorsDarmon A, Bar-Noy S, Ginsburg H, Cabantchik ZI
JournalBiochim Biophys Acta
PubMed ID3893545
'The two major membrane glycoproteins of human red cells, glycophorin and band 3, the anion exchange protein, were isolated from cells exofacially labeled with fluorescein and reconstituted into vesicles with defined transmembrane disposition. Uniform orientation of polypeptides was accomplished by two procedures: Vesicles with single protein units were obtained by ... More
Water exchange through erythrocyte membranes: nuclear magnetic resonance studies on the effects of inhibitors and of chemical modifications of human membranes.
AuthorsBenga G, Pop VI, Popescu O, Ionescu M, Mihele V
JournalJ Membr Biol
PubMed ID6644795
'The changes in water diffusion across human erythrocyte membranes following exposure to various inhibitors and proteolytic enzymes have been studied on isolated erythrocytes suspended in isotonic buffered solutions. An important issue was to investigate whether the sulfhydryl reacting reagents that have been applied in osmotic experiments showed similar effects on ... More
The mechanisms of inhibition of anion exchange in human erythrocytes by 1-ethyl-3-[3-(trimethylammonio)propyl]carbodiimide.
AuthorsWerner PK, Reithmeier RA
JournalBiochim Biophys Acta
PubMed ID2454665
'Treatment of human erythrocytes with the membrane-impermeant carbodiimide 1-ethyl-3-[3-(trimethylammonio)propyl]carbodiimide (ETC) in citrate-buffered sucrose leads to irreversible inhibition of phosphate-chloride exchange. The level of transport inhibition produced was dependent on the concentration of citrate present during treatment, with a maximum of approx. 60% inhibition. [14C]Citric acid was incorporated into Band 3 ... More
Regulation of Cl/HCO3 exchange in gastric parietal cells.
AuthorsThomas HA, Machen TE
JournalCell Regul
PubMed ID1742343
'Microspectrofluorimetry of the fluorescent indicators 2',7'-bis-(2-carboxyethyl)-5(and-6)carboxyfluorescein and 6-methoxy-N-(3-sulfopropyl)-quinolinium was used to measure intracellular pH (pHi), intracellular Cl (Cli), and transmembrane fluxes of HCO3 and Cl in single parietal cells (PC) in isolated rabbit gastric glands incubated in HCO3/CO2-buffered solutions. Steady-state pHi was 7.2 in both resting (50 microM cimetidine) and ... More
The role of anions in pH regulation of Leishmania major promastigotes.
AuthorsVieira L, Lavan A, Dagger F, Cabantchik ZI
JournalJ Biol Chem
PubMed ID8206930
'The pH regulation of Leishmania major promastigotes was studied as a function of the ionic composition of the medium and in response to acid and alkali load. Intracellular pH (pHi) was monitored by on-line ratio fluorescence using the fluorescence-dependent pH indicator 2',7'-bis-(carboxyethyl)-5,6-carboxyfluorescein (BCECF). In Cl(-)-based medium (pH 7.4, 30 degrees ... More
Accumulation of intracellular HCO3- by Na(+)-HCO3- cotransport in interlobular ducts from guinea-pig pancreas.
AuthorsIshiguro H, Steward MC, Lindsay AR, Case RM
JournalJ Physiol
PubMed ID8866360
'1. Short segments of interlobular duct were microdissected from guinea-pig pancreas following enzymatic digestion. After overnight culture, intracellular pH (pH1) and Na+ concentration ([Na+]i) were measured by microfluorometry in duct cells loaded with either the pH-sensitive fluoroprobe 2''7''-bis(2-carboxyethyl)-5(6)-carboxyfluorescein (BCECF) or the sodium-binding benzofuran isophthalate (SBFI). 2. The transporters responsible for ... More
A role for band 4.2 in human erythrocyte band 3 mediated anion transport.
AuthorsMalik S, Sami M, Watts A
JournalBiochemistry
PubMed ID8399133
'Human erythrocyte band 3 was purified essentially free of peripheral proteins, in particular band 4.2, using affinity chromatography. Band 3 protein was then reconstituted into liposomes of lipid type and ratio approximating that of erythrocyte membranes. Stilbenedisulfonate inhibition of band 3 mediated efflux of radiolabeled sulfate from preloaded liposomes was ... More
A rabbit erythrocyte membrane protein associated with L-lactate transport.
AuthorsJennings ML, Adams-Lackey M
JournalJ Biol Chem
PubMed ID7130184
'Chemical Labeling has been employed to attempt to identify the lactate transport protein of rabbit erythrocytes, which have a very high capacity for stereoselective lactate transport. The lactate transport protein catalyzes lactate/proton cotransport (or lactate/hydroxyl exchange) at physiological pH, as demonstrated by uphill proton fluxes induced by lactate gradients. However, ... More
An apical K(+)-dependent HCO(3)- transport pathway opposes transepithelial HCO(3)- absorption in rat medullary thick ascending limb.
AuthorsWatts BA, Good DW
JournalAm J Physiol Renal Physiol
PubMed ID15026301
'Absorption of HCO(3)(-) in the medullary thick ascending limb (MTAL) is mediated by apical membrane Na(+)/H(+) exchange. The identity and function of other apical acid-base transporters in this segment have not been defined. The present study was designed to examine apical membrane HCO(3)(-)/OH(-)/H(+) transport pathways in the rat MTAL and ... More
Band 3 Memphis variant II. Altered stilbene disulfonate binding and the Diego (Dia) blood group antigen are associated with the human erythrocyte band 3 mutation Pro854-->Leu.
AuthorsBruce LJ, Anstee DJ, Spring FA, Tanner MJ
JournalJ Biol Chem
PubMed ID8206915
'Band 3 Memphis is a commonly occurring polymorphic form of the human red cell anion transporter (band 3, AE1). Band 3 Memphis migrates more slowly on an SDS-polyacrylamide gel than normal band 3 and results from a point mutation Lys56-->Glu. Two types of band 3 Memphis, variants I and II, ... More
Rat liver microsomal glucose-6-P translocase. Effect of physiological status on inhibition and labeling by stilbene disulfonic acid derivatives.
AuthorsZoccoli MA, Hoopes RR, Karnovsky ML
JournalJ Biol Chem
PubMed ID6288677
'Intact microsomes from groups of fed, fasted, glucocorticoid-treated (triamcinolone) and diabetic (alloxan) rats were reacted with 4,4''-diisothiocyanostilbene-2,2''-disulfonic (DIDS), a specific inhibitor of microsomal glucose-6-P translocase. The concentrations that inhibit by 50% were 41 +/- 2, 31 +/- 1, 39 +/- 4, and 18 +/- 1 microM (mean +/- S.E.; n ... More
Identification of the eosinyl-5-maleimide reaction site on the human erythrocyte anion-exchange protein: overlap with the reaction sites of other chemical probes.
AuthorsCobb CE, Beth AH
JournalBiochemistry
PubMed ID1701324
'The anion-exchange protein (band 3) reaction site in human erythrocytes for the fluorescent/phosphorescent probe eosinyl-5-maleimide (EMA) has been identified. Proteolytic dissection of band 3 in situ indicated that EMA reacts with the membrane-spanning Mr 17K peptide produced by chymotrypsin cleavage of band 3 in intact erythrocytes followed by removal of ... More
Formation and properties of tetramers of band 3 protein from human erythrocyte membranes in planar lipid bilayers.
AuthorsBenz R, Tosteson MT, Schubert D
JournalBiochim Biophys Acta
PubMed ID6466677
'Lipid bilayer experiments were performed in the presence of solubilized band 3 protein from human red cell membranes. Band 3 protein increased the conductance of the lipid membranes by several orders of magnitude. Membrane conductance was found to be dependent on the fourth power of protein concentration. This shows that ... More
Kinetics of conformational changes associated with inhibitor binding to the purified band 3 transporter. Direct observation of allosteric subunit interactions.
AuthorsSalhany JM, Cordes KA, Schopfer LM
JournalBiochemistry
PubMed ID8338838
'Subunit interaction effects were identified for isolated human erythrocyte band 3, the anion exchanger, by observing both static and stopped-flow kinetic protein fluorescence changes associated with inhibitor binding to the intramonomeric stilbenedisulfonate site. We measured the rate of conformational changes associated with reversible binding of H2DIDS (4,4''-diisothiocyanodihydrostilbene-2,2''-disulfonate). The rate of ... More
Interactions between mutant and wild-type band 3 subunits in hereditary Southeast Asian ovalocytic red blood cell membranes.
AuthorsSalhany JM, Schopfer LM
JournalBiochemistry
PubMed ID8555182
'Red cell membranes from individuals with Southeast Asian ovalocytosis (SAO) contain approximately equal proportions of wild-type band 3 and a mutant SAO band 3 which lacks residues 400-408. It is known that the Vmax for anion exchange in SAO cells is reduced by about 50%, that SAO band 3 does ... More
Reversible and irreversible inhibition, by stilbenedisulphonates, of lactate transport into rat erythrocytes. Identification of some new high-affinity inhibitors.
AuthorsPoole RC, Halestrap AP
JournalBiochem J
PubMed ID2025218
'1. Inhibition of L-lactate transport into rat erythrocytes by stilbenedisulphonates was studied under conditions which allowed the contribution of reversible and irreversible inhibition to be assessed. 2. At low temperatures (7 degrees C), 4,4''-di-isothiocyanostilbene-2,2''-disulphonate (DIDS) and other stilbenedisulphonates were found to inhibit lactate transport instantaneously, in a manner which was ... More
Chemical modification and labeling of glutamate residues at the stilbenedisulfonate site of human red blood cell band 3 protein.
AuthorsJennings ML, Anderson MP
JournalJ Biol Chem
PubMed ID2879841
'A new method has been developed for the chemical modification and labeling of carboxyl groups in proteins. Carboxyl groups are activated with Woodward''s reagent K (N-ethyl-5-phenylisoxazolium 3''-sulfonate), and the adducts are reduced with [3H]BH4. The method has been applied to the anion transport protein of the human red blood cell ... More
Chloride conductive pathways which support electrogenic H+ pumping by Leishmania major promastigotes.
AuthorsVieira L, Slotki I, Cabantchik ZI
JournalJ Biol Chem
PubMed ID7890641
'The proton extrusion mechanisms of Leishmania promastigotes were studied in terms of electrogenic movements of protons and anions (Cl- and HCO3-). Changes in membrane potential (Vm) and intracellular pH (pHi) were monitored fluorimetrically with the potential sensitive dye bis-oxonol and the pH-sensitive dye tetraacethoxymethyl 2',7'-bis-(carboxyethyl)-5,6-carboxyfluorescein, respectively. In nominal bicarbonate-free medium ... More
Trapping of inhibitor-induced conformational changes in the erythrocyte membrane anion exchanger AE1.
AuthorsTang XB, Casey JR
JournalBiochemistry
PubMed ID10545179
'AE1, the chloride/bicarbonate anion exchanger of the erythrocyte plasma membrane, is highly sensitive to inhibition by stilbene disulfonate compounds such as DIDS (4,4''-diisothiocyanostilbene-2, 2''-disulfonate) and DNDS (4,4''-dinitrostilbene-2,2''-disulfonate). Stilbene disulfonates recruit the anion binding site to an outward-facing conformation. We sought to identify the regions of AE1 that undergo conformational changes ... More
CFTR functions as a bicarbonate channel in pancreatic duct cells.
AuthorsIshiguro H, Steward MC, Naruse S, Ko SB, Goto H, Case RM, Kondo T, Yamamoto A,
JournalJ Gen Physiol
PubMed ID19204187
'Pancreatic duct epithelium secretes a HCO(3)(-)-rich fluid by a mechanism dependent on cystic fibrosis transmembrane conductance regulator (CFTR) in the apical membrane. However, the exact role of CFTR remains unclear. One possibility is that the HCO(3)(-) permeability of CFTR provides a pathway for apical HCO(3)(-) efflux during maximal secretion. We ... More
Characterization of the stilbenedisulfonate binding site on band 3.
AuthorsSchopfer LM, Salhany JM
JournalBiochemistry
PubMed ID7599124
'Stilbenedisulfonates are potent inhibitors of Band 3 mediated anion exchange. They bind tightly to the protein and form a 1-to-1 reversible complex. Those stilbenedisulfonates which contain isothocyanato groups such as DIDS (4,4'-diisothiocyanato-2,2'-stilbenedisulfonate) and H2DIDS (4,4'-diisothiocyanatodihydrostilbene-2,2'-disulfonate) can also react rapidly with lysine residues within the binding pocket to yield an irreversible ... More
Interactions of inhibitors on anion transporter of human erythrocyte.
AuthorsFröhlich O, Gunn RB
JournalAm J Physiol
PubMed ID3826335
'Chloride tracer efflux was measured from intact human erythrocytes into media containing different chloride concentrations and different concentrations of the inhibitors 4,4''-dinitrostilbene-2-2''-disulfonate (DNDS), N-(4-azido-2-nitrophenyl)-2-aminoethylsulfonate (NAP-taurine), phloretin, and sulfate. The data were analyzed to test whether these inhibitors were mutually exclusive with each other or whether they could bind at the ... More
Inverse effects of dansylation of red blood cell membrane on band 3 protein-mediated transport of sulphate and chloride.
AuthorsLepke S, Passow H
JournalJ Physiol
PubMed ID6897945
'1. Dansylation of the red cell membrane produces inverse effects on SO(4) (2-) and Cl(-) equilibrium exchange. The former is enhanced by several orders of magnitude (Legrum, Fasold & Passow, 1980), the latter is inhibited. Both effects are potentiated after dansylation in the presence of 2-(4-amino-3-sulphophenyl)-6-methyl-7-benzothiazol sulphonic acid (APMB), a ... More
Kinetic evidence for ternary complex formation and allosteric interactions in chloride and stilbenedisulfonate binding to band 3.
AuthorsSalhany JM, Sloan RL, Cordes KA, Schopfer LM
JournalBiochemistry
PubMed ID7918409
'The molecular basis for chloride and stilbenedisulfonate interaction with band 3 was investigated by measuring the kinetics of stilbenedisulfonate release from its complex with the transporter. We found that 150 mM NaCl accelerated the rate of release of DBDS (4,4''-dibenzamidostilbene-2,2''-dibenzamidostilbene-2,2''-disu lfonate) and H2DIDS (4,4''-diisothiocyanodihydrostilbene-2,2''-disulfonate) by more than 10-fold at constant ... More
Roles of histidine 752 and glutamate 699 in the pH dependence of mouse band 3 protein-mediated anion transport.
AuthorsMüller-Berger S, Karbach D, Kang D, Aranibar N, Wood PG, Rüterjans H, Passow H
JournalBiochemistry
PubMed ID7626601
'In the accompanying paper we have shown that four different histidine residues are involved in the maintenance of mouse band 3 in a state in which it is able to execute its anion transport function. Here we focus on the functional significance of His 752 and demonstrate that this residue, ... More
Amino acid residues complexed with eosin 5-isothiocyanate in band 3 protein of the human erythrocyte.
AuthorsChiba T, Sato Y, Suzuki Y
JournalBiochim Biophys Acta
PubMed ID2423129
'The amino-acid residues of band 3 protein taking part in the ionic interaction with an anion-transport inhibitor, eosin 5-isothiocyanate (EITC), were determined by pH titration. The plots of the absorbance of EITC-ghost system against pH reveal five equilibria, at pH 3.7, 6.4, 8.0, 11.0 and 13.1. Since the three equilibria, ... More
A study of the relationship between inhibition of anion exchange and binding to the red blood cell membrane of 4,4'-diisothiocyano stilbene-2,2'-disulfonic acid (DIDS) and its dihydro derivative (H2DIDS).
AuthorsLepke S, Fasold H, Pring M, Passow H
JournalJ Membr Biol
PubMed ID978716
'DIDS (4,4''-diisothiocyano stilbene-2,2''-disulfonic acid) and H2DIDS (4,4''-diisothiocyano-1,2-diphenyl ethane-2,2''-disulfonic acid) binding to the human red cell membrane proteins were studied as a function of concentration, temperature and time. Most binding sites were common to both. The common sites were in band 3 of SDS polyacrylamide gel electropherograms (Steck, 1974. J. Cell ... More
Cytosolic pH regulation in osteoblasts. Regulation of anion exchange by intracellular pH and Ca2+ ions.
AuthorsGreen J, Yamaguchi DT, Kleeman CR, Muallem S
JournalJ Gen Physiol
PubMed ID2299328
'Measurements of cytosolic pH (pHi) 36Cl fluxes and free cytosolic Ca2+ concentration ([Ca2+]i) were performed in the clonal osteosarcoma cell line UMR-106 to characterize the kinetic properties of Cl-/HCO3- (OH-) exchange and its regulation by pHi and [Ca2+]i. Suspending cells in Cl(-)-free medium resulted in rapid cytosolic alkalinization from pHi ... More
Anion transport across the erythrocyte membrane, in situ proteolysis of band 3 protein, and cross-linking of proteolytic fragments by 4,4'-diisothiocyano dihydrostilbene-2,2'-disulfonate.
AuthorsJennings ML, Passow H
JournalBiochim Biophys Acta
PubMed ID486455
'Extracellular chymotrypsin cleaves the 95 000 dalton protein that migrates in band 3 of SDS-polyacrylamide gel electropherograms of the erythrocyte membrane into fragments of 60 000 and 35 000 daltons, but not further. Minor components of band 3 that remain at the original 95 000 dalton location may be eluted ... More
Characterization of eosin 5-isothiocyanate binding site in band 3 protein of the human erythrocyte.
AuthorsChiba T, Sato Y, Suzuki Y
JournalBiochim Biophys Acta
PubMed ID2432938
'The characteristics of the anion transport system in human erythrocyte, which can be modified by eosin 5-isothiocyanate (EITC), were studied using the pH titration method and by measuring the sulfate efflux. Based on the pH dependence of EITC binding to the erythrocyte ghosts, it was found that the reaction rate ... More
Interactions between transport inhibitors at the anion binding sites of the band 3 dimer.
AuthorsMacara IG, Cantley LC
JournalBiochemistry
PubMed ID7295667
'Evidence is presented that the binding of aromatic disulfonates to the external transport sites of the red cell anion-exchange protein (band 3) can exhibit negative cooperativity. Fluorescence resonance energy transfer has been used to compare the affinities of an aromatic disulfonate 4,4'-bis-(4-nitro-2,1,3-benzoxadiazolyl)dihydrostilbene-2,2'-disulfonate[H2(NBD)2DS] for "empty" band 3 dimers (in which neither ... More
An assay of malaria parasite invasion into human erythrocytes. The effects of chemical and enzymatic modification of erythrocyte membrane components.
AuthorsBreuer WV, Ginsburg H, Cabantchik ZI
JournalBiochim Biophys Acta
PubMed ID6338931
'Invasion of erythrocytes by malaria parasites is known to be blocked by proteolytic digestion of merozoite receptors allegedly present in red cell membranes. This information was used in the present work to develop a simple and convenient assay for parasite invasion into red blood cells and for evaluating the role ... More
Cytosolic pH regulation in chicken enterocytes: Na(+)-independent regulatory cell alkalinization.
AuthorsPeral MJ, Calonge ML, Ilundáin AA
JournalBiochim Biophys Acta
PubMed ID7530492
'The mechanisms involved in intracellular pH (pHi) recovery from an acid load have been investigated in enterocytes isolated from chicken. Following an intracellular acidification, by abrupt withdrawal of NH4Cl, pHi alkalinized in the nominally absence of Na+ and bicarbonate. This Na(+)- and bicarbonate-independent (NBI) regulatory cell alkalinization became negligible when ... More
Effect of DIDS on renal tubular transport.
AuthorsKoschier FJ, Stokols MF, Goldinger JM, Acara M, Hong SK
JournalAm J Physiol
PubMed ID7361895
'Two stilbene derivates that had been used to covalently label the Cl- carrier in the erythrocyte were investigated for reactivity with the renal organic anion system. These compounds, 4,4''-diisothiocyanostilbene-2,2''-disulfonate (DIDS) and (4,4''-diisothiocyano)-dihydrostilbene-2,2''-disulfonate (H2DIDS), were found to be potent inhibitors (Ki congruent to 35 microM) of p-aminohippurate (PAH) transport in the ... More
Inhibition of anion transport across red blood cells with 1,2-cyclohexanedione.
AuthorsZaki L
JournalBiochem Biophys Res Commun
PubMed ID7236263
Transport of anions in Ehrlich ascites tumor cells: effects of disulfonic acid stilbene in relation to transport mechanism.
AuthorsLevinson C
JournalAnn N Y Acad Sci
PubMed ID6930841
Membrane proteins related to anion permeability of human red blood cells. II. Effects of proteolytic enzymes on disulfonic stilbene sites of surface proteins.
AuthorsCabantchik ZI, Rothstein A
JournalJ Membr Biol
PubMed ID4838038
Membrane proteins related to anion permeability of human red blood cells. I. Localization of disulfonic stilbene binding sites in proteins involved in permeation.
AuthorsCabantchik ZI, Rothstein A
JournalJ Membr Biol
PubMed ID4838037
The anion transport system of the red blood cell. The role of membrane protein evaluated by the use of 'probes'.
AuthorsCabantchik ZI, Knauf PA, Rothstein A
JournalBiochim Biophys Acta
PubMed ID29666
Effect of two inhibitors of anion transport on the hydrolysis of glucose 6-phosphate by rat liver microsomes. Covalent modification of the glucose 6-P transport component.
AuthorsZoccoli MA, Karnovsky ML
JournalJ Biol Chem
PubMed ID6243291
Inhibition and labelling of the erythrocyte lactate transporter by stilbene disulphonates.
AuthorsPoole RC, Halestrap AP
JournalBiochem Soc Trans
PubMed ID2088893
Photohemolysis of human erythrocytes labeled in band 3 with eosin-isothiocyanate.
AuthorsPooler JP, Girotti AW
JournalPhotochem Photobiol
PubMed ID2431425
Intracellular ion activities and membrane transport in parietal cells measured with fluorescent dyes.
AuthorsNegulescu PA, Machen TE
JournalMethods Enzymol
PubMed ID2074799
The purpose of this chapter is to summarize the methods we have usedfor measuring intracellular pH with BCECF, intracellular calcium with fura-2 and intracellular sodium with SBFI in single, identified cells of gastricglands isolated from rabbits. ... More
The amino acid conjugate formed by the interaction of the anion transport inhibitor 4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid (DIDS) with band 3 protein from human red blood cell membranes.
AuthorsRamjeesingh M, Gaarn A, Rothstein A
JournalBiochim Biophys Acta
PubMed ID6783088
The specific anion transport inhibitor 4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid (DIDS) and its reduced analog (H2DIDS), when irreversibly bound to band 3 protein of the red blood cell membrane, form amino acid conjugates through interaction with the epsilon-amino group of a particular lysine residue. The specific residue is located in a transmembrane segment ... More
Identification by site-directed mutagenesis of Lys-558 as the covalent attachment site of H2DIDS in the mouse erythroid band 3 protein.
AuthorsBartel D, Hans H, Passow H
JournalBiochim Biophys Acta
PubMed ID2508756
After functional expression of mouse erythroid band 3 by cRNA microinjection into Xenopus oocytes, 36Cl- efflux is irreversibly inhibited by H2DIDS. When a cRNA is injected that is derived from a cDNA in which the nucleotides encoding for lysine-558 were replaced by nucleotides encoding for asparagine, transport and inhibition of ... More
Band 3, an accidental flippase for anionic phospholipids?
AuthorsVondenhof A, Oslender A, Deuticke B, Haest CW
JournalBiochemistry
PubMed ID8161506
The inward translocation of the monovalent anionic phospholipid 1-palmitoyl-sn-glycero-3-phosphomethanol in the membrane of human erythrocytes is a fast process (t/2 = 11 min, 37 degrees C). Translocation of the protonated uncharged phospholipid is not responsible for the fast flip rate, and mediation of translocation by the aminophospholipid flippase could be ... More
Heavy meromyosin binds actin with negative cooperativity.
AuthorsHighsmith S
JournalBiochemistry
PubMed ID338033
The association of fluorescently labeled heavy meromyosin (HMM) and F-actin was measured by time-resolved fluorescence depolarization. The effects of varying the protein concentrations, temperature, KCl concentration, and pH were determined. Measurements of HMM mobility supported a model of no interaction between the two heads in the absence of actin. Measurements ... More
The phorbol ester PMA and cyclic AMP activate different Cl(-) and HCO3(-) fluxes in C127 cells expressing CFTR.
AuthorsZegarra-Moran O, Porcelli AM, Rugolo M
JournalBiochim Biophys Acta
PubMed ID11342000
In mouse mammary epithelial C127 cells expressing wild-type cystic fibrosis transmembrane conductance regulator (CFTR), chloride efflux, measured with the Cl(-)-sensitive dye 6-methoxy-N-(3-sulfopropyl)quinolinium (SPQ), was stimulated by activation of protein kinase A with cyclic AMP elevating agents forskolin plus 3-isobutyl-1-methyl-xanthine (IBMX) and, to a less extent, by activation of protein kinase ... More
Inhibition of anion permeability of sarcoplasmic reticulum vesicles by stilbene derivatives and the identification of an inhibitor-binding protein.
AuthorsKasai M, Taguchi T
JournalBiochim Biophys Acta
PubMed ID7236689
The permeability of sarcoplasmic reticulum vesicles to sulfate ions was inhibited by diisothiocyano-1,2-diphenylethane-2,2'-disulfonic acid (H2DIDS), which is a potent inhibitor of anion permeability in red blood cell membrane. The amount of H2DIDS bound to the vesicles was determined by using [3H]-H2DIDS. Apparent half inhibition of sulfate permeation was observed on ... More
Functional evidence for distinct interaction of hydrophobic arylisothiocyanates with the erythrocyte anion transport protein.
AuthorsCacciola SO, Sigrist H, Reist M, Cabantchik ZI, Zahler P
JournalJ Membr Biol
PubMed ID6492134
Human erythrocytes were treated with various hydrophobic arylisothiocyanates under conditions which favor modification of distinct proteinaceous nucleophiles. The morphological appearance of phenylisothiocyanate-treated cells was discoid and membrane-bound hydrolases (human acetylcholinesterase, sheep phospholipase A2) were fully active following membrane modification. Noncharged hydrophobic arylisothiocyanates, including phenylisothiocyanate, beta-naphthylisothiocyanate and heterobifunctional azidoarylisothiocyanates inhibited [35S]-sulfate ... More
Inhibition of sodium-phosphate cotransport in renal brush-border membranes with the stilbenedisulfonate, H2-DIDS.
AuthorsAzzarolo AM, Ritchie G, Quamme G
JournalBiochim Biophys Acta
PubMed ID1932052
Membrane proteins involved with sodium/phosphate cotransport across the renal brush border provide the sensitive control for phosphate homeostasis. The present study describes the inhibition of sodium/phosphate cotransport with the stilbenedisulfonate derivatives, DIDS and H2-DIDS. Preincubation of the rat brush-border membrane vesicles with H2-DIDS led to the inhibition of sodium-dependent phosphate ... More
Protein kinase C activates chloride conductance in C127 cells stably expressing the cystic fibrosis gene.
AuthorsDechecchi MC, Tamanini A, Berton G, Cabrini G
JournalJ Biol Chem
PubMed ID7684379
The regulatory domain (R domain) of the cystic fibrosis transmembrane conductance regulator (CFTR) is phosphorylated by protein kinase A and protein kinase C (PKC) in vivo (Picciotto, M. R., Cohn, J. A., Bertuzzi, G., Greengard, P., and Nairn, A. C. (1992) J. Biol. Chem. 267, 12742-12752), but so far the ... More
Synthesis of tritiated 4,4'-diisothiocyano-2,2'-stilbene disulfonic acid ([3H]DIDS) and its covalent reaction with sites related to anion transport in human red blood cells.
AuthorsShip S, Shami Y, Breuer W, Rothstein A
JournalJ Membr Biol
PubMed ID864693
The potent and specific inhibitor of anion permeability, 4,4'-diisothicyanostilbene-2,2'-disulfonic acid (DIDS) was synthesized in tritiated form ([3H]DIDS) from tritiated 5-nitrotoluene-o-sulfonic acid. Its reactions with and effects on red blood cells were compared with those of a reduced form ([3H]H2DIDS), previously used as a tracer for DIDS. The rate of covalent ... More
Identification of the Cl- transport site of human red blood cells by a kinetic analysis of the inhibitory effects of a chemical probe.
AuthorsShami Y, Rothstein A, Knauf PA
JournalBiochim Biophys Acta
PubMed ID638145
H2DIDS, the dihydro analog of DIDS (4,4'-diisothiocyanostilbene-2,2'-disulfonic acid) can interact covalently with membrane sites, resulting in an irreversible inhibition of anion exchange. At low temperatures (0 degrees C) and for relatively short times, however, its interaction is largely reversible, so that a kinetic analysis of the nature of its inhibitory ... More
Stilbene disulfonic acids. CD4 antagonists that block human immunodeficiency virus type-1 growth at multiple stages of the virus life cycle.
AuthorsCardin AD, Smith PL, Hyde L, Blankenship DT, Bowlin TL, Schroeder K, Stauderman KA, Taylor DL, Tyms AS
JournalJ Biol Chem
PubMed ID2071607
The stilbene disulfonic acids 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS), 4,4'-diisothiocyanatodihydrostilbene-2,2'-disulfonic acid and, 4-acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic acid bound the variable-1 immunoglobulin-like domain of CD4 on JM cells. The interaction blocked the binding of the anti-CD4 monoclonal antibody OKT4A and the envelope glycoprotein gp120 of the human immunodeficiency virus type-1 (HIV-1). DIDS inhibited the acute infection ... More
Reductive methylation of the two 4,4'-diisothiocyanodihydrostilbene-2,2'-disulfonate-binding lysine residues of band 3, the human erythrocyte anion transport protein.
AuthorsJennings ML
JournalJ Biol Chem
PubMed ID6806279
The bifunctional anion transport inhibitor 4,4'p-diisothiocyanodihydrostilbene-2,2'-disulfonate (H2DIDS) can react covalently with both chymotryptic peptides of band 3, the human erythrocyte anion transport protein. The functional roles of the two sites of covalent H2DIDS attachment have been investigated using reductive methylation with formaldehyde and borohydride, which is a substrate for band ... More
Enhancement of divalent anion transport across the human red blood cell membrane by the water-soluble dansyl chloride derivative 2-(N-piperidine)ethylamine-1-naphthyl-5-sulfonylchloride (PENS-Cl).
AuthorsRaida M, Passow H
JournalBiochim Biophys Acta
PubMed ID3838248
Sulfate transport across the red cell membrane is enhanced by the newly synthesised, water-soluble and nonpenetrating dansyl chloride derivative 2-(N-piperidine)ethylamine-1-naphthyl-5-sulfonylchloride (PENS-Cl). The transport is only enhanced if the potentiating agent 2-(4-aminophenyl-3-sulfonic acid)-6-methylbenzothiazol-7-sulfonic acid (APMB) is present during incubation with PENS-Cl. The enhanced flux is reduced by the anion-transport inhibitor 4,4'-diisothiocyanatodihydrostilbene-2,2'-disulfonate ... More
Macromolecular conjugates of transport inhibitors: new tools for probing topography of anion transport proteins.
AuthorsEidelman O, Yani P, Englert HC, Lang HG, Greger R, Cabantchik ZI
JournalAm J Physiol
PubMed ID2035616
Macromolecular-conjugated, water-soluble, membrane-impermeant compounds were designed and assessed as topological probes for chloride-transporting agencies. The novel compounds were derivatives of either disulfonic stilbene (DS) and benzylaminoethylsulfonate (BS), "classical" inhibitors of erythrocyte chloride-bicarbonate exchange, or of phenylanthranilates (PA), high-affinity blockers of epithelial chloride channels. Covalent reactive derivatives of various DS, BS, ... More
Kinetics of DIDS inhibition of swelling-activated K-Cl cotransport in low K sheep erythrocytes.
AuthorsDelpire E, Lauf PK
JournalJ Membr Biol
PubMed ID1593613
The inhibitory effect of various stilbene disulfonates was examined on the swelling-activated Cl-dependent K transport (K-Cl cotransport) in low K sheep erythrocytes. Both diisothiocyanatostilbenes H2DIDS and DIDS were found to be potent inhibitors. The DIDS concentration yielding 50% inhibition (IC50) of KCl cotransport was 60 microM in the absence of ... More
Cl-/base exchange and cellular pH regulation in enterocytes isolated from chick small intestine.
AuthorsCalonge ML, Molina MT, Ilundáin A
JournalBiochim Biophys Acta
PubMed ID1730020
Intracellular pH (pHi) and Cl-/base exchange activity have been examined in isolated chicken enterocytes, both in the presence and absence of 25 mM HCO3-/5% CO2. Intracellular pH was measured with BCECF, a pH-sensitive carboxyfluorescein derivative. Under resting conditions pHi was 7.17 in Hepes and 7.12 in HCO3(-)-buffered solutions. Cells became ... More
Biphasic effect of angiotensin II on intracellular sodium concentration in rat proximal tubules.
AuthorsReilly AM, Harris PJ, Williams DA
JournalAm J Physiol
PubMed ID7573486
Intracellular Na+ concentration ([Na+]i) was determined using ratiometric measurement of the Na(+)-sensitive fluorescent probe, sodium-binding benzofuran isophthalate (SBFI). Angiotensin II (ANG II, 10(-11)-10(-7) M), applied to the basolateral membrane of rat isolated proximal convoluted tubules, induced a rapid and reversible dose-dependent increase in [Na+]i, which was initiated within 300 ms. ... More
Chloride transport in apical membrane vesicles from bovine tracheal epithelium: characterization using a fluorescent indicator.
AuthorsFong P, Illsley NP, Widdicombe JH, Verkman AS
JournalJ Membr Biol
PubMed ID3210223
C1 transport in apical membrane vesicles derived from bovine tracheal epithelial cells was studied using the C1-sensitive fluorescent indicator 6-methoxy-N-(3-sulfopropyl) quinolinium. With an inwardly directed 50 mM C1 gradient at 23 degrees C, the initial rate of C1 entry (JC1) was increased significantly from 0.32 +/- 0.12 nmol.sec-1.mg protein-1 (mean ... More
Protoporphyrin-induced photodynamic effects on band 3 protein of human erythrocyte membranes.
AuthorsDubbelman TM, De Goeij AF, Christianse K, Van Steveninck J
JournalBiochim Biophys Acta
PubMed ID7317401
In previous studies it has been shown that protoporphyrin-induced photodynamic effects on red blood cells are caused by photooxidation of amino acid residues in membrane proteins and by the subsequent covalent cross-linking of these proteins. Band 3, the anion transport protein of the red blood cell membrane, has a relatively ... More
Molecular and functional evidence for a Na(+)-HCO3(-)-cotransporter in sheep ruminal epithelium.
AuthorsHuhn K, Müller F, Honscha KU, Pfannkuche H, Gäbel G
JournalJ Comp Physiol [B]
PubMed ID12820006
The present study aimed to identify the HCO3(-)-dependent mechanisms contributing to the homeostasis of the intracellular pH (pHi) in ruminal epithelial cells of sheep. Therefore, pHi was measured spectrofluorometrically in primary cultured ruminal epithelial cells loaded with the pH-sensitive fluorescent dye, 2',7'-bis(carboxyethyl)-5(6')-carboxyfluorescein acetoxymethyl ester. Switching from a HEPES-buffered to a ... More
Use of MQAE for measurement of intracellular [Cl-] in cultured aortic smooth muscle cells.
AuthorsKoncz C, Daugirdas JT
JournalAm J Physiol
PubMed ID7810712
A novel fluorescent indicator, N-[ethoxycarbonylmethyl]-6-methoxy-quinolinium bromide (MQAE), was used to measure intracellular chloride concentration ([Cl-]i) in primary cultures of rat aortic smooth muscle cells (VSMC). The hydrolytic and fluorescent properties of the dye were characterized. The intracellular Stern-Volmer constant was calculated to be 25 M-1. Cl- efflux curves were characteristic ... More
Differential sensitivity of stilbenedisulfonates in their reaction with band 3 HT (Pro-868-->Leu).
AuthorsSalhany JM, Schopfer LM, Kay MM, Gamble DN, Lawrence C
JournalProc Natl Acad Sci U S A
PubMed ID8524861
Band 3 HT (Pro-868-->Leu) is a mutant anion exchange protein which has several phenotypic characteristics, including a 2- to 3-fold larger Vmax, and reduced covalent binding of the anion transport inhibitor 4,4'-diisothiocyanodihydrostilbene-2,2'-disulfonate (H2DIDS). We have used fluorescence kinetic methods to study inhibitor binding to band 3 to determine if the ... More
Cross-linking of the erythrocyte (Na+,K+)-ATPase. Chemical cross-linkers induce alpha-subunit-band 3 heterodimers and do not induce alpha-subunit homodimers.
AuthorsMartin DW, Sachs JR
JournalJ Biol Chem
PubMed ID1331105
Earlier studies (Periyasamy, S. M., Huang, W.-H., and Askari, A. (1983) J. Biol. Chem. 258, 9878-9885) suggested that Cu2+ and o-phenanthroline induced the formation of cross-linked homodimers between alpha-subunits of the erythrocyte (Na+,K+)-ATPase. This was interpreted as indicating that alpha-subunits existed in close proximity in native erythrocyte membranes. The alpha-subunit ... More
Renal brush-border chloride transport mechanisms characterized using a fluorescent indicator.
AuthorsChen PY, Illsley NP, Verkman AS
JournalAm J Physiol
PubMed ID3337241
Cl transport mechanisms in brush-border membrane vesicles (BBMV) isolated from rabbit renal cortex were characterized using the Cl-sensitive fluorescent indicator 6-methoxy-N-[3-sulfopropyl]quinolinium (SPQ). In control experiments using 36Cl, SPQ did not itself alter rates for Cl transport. Cl fluxes (JCl) in nanomoles per second per milligram vesicle protein in response to ... More
Characterization of Mg2+ transport in brush border membrane vesicles of rabbit ileum studied with mag-fura-2.
AuthorsJüttner R, Ebel H
JournalBiochim Biophys Acta
PubMed ID9518549
Mg2+ transport in rabbit ileal brush border membrane vesicles (BBMV) was characterized by means of a modified mag-fura-2 technique. In the presence of an i>o Na+ gradient, BBMV showed a saturable Mg2+ uptake with a Km of 1.64 mmol l-1. There was no evidence of an overshoot. K+, Li+, and ... More
Chemical probes for anion transporters of mammalian cell membranes.
AuthorsCabantchik ZI, Greger R
JournalAm J Physiol
PubMed ID1566811
Mammalian cell membranes harbor several types of chloride channels, chloride-cation symporters/cotransporters, and several classes of anion exchangers/antiporters. These transport systems subserve different cellular or organismic functions, depending on the nature of the cell, the spatial organization of transporters, and their functional interplay. Chemical probing has played a central role in ... More
Further characterization of membrane proteins involved in the transport of organic anions in hepatocytes. Comparison of two different affinity labels: 4,4'-diisothiocyano-1,2-diphenylethane-2,2'-disulfonic acid and brominated taurodehydrocholic acid.
AuthorsZiegler K, Frimmer M, Fasold H
JournalBiochim Biophys Acta
PubMed ID6691970
4,4'-Diisothiocyano-1,2-diphenylethane-2,2'-disulfonic acid (H2DIDS) known as an irreversible inhibitor of the anion transport in red blood cells (Cabantchik, Z.I. and Rothstein, A. (1972) J. Membrane Biol. 10, 311-330) blocks also the uptake of bile acids and of some foreign substrates in isolated hepatocytes (Petzinger, E. and Frimmer, M. (1980) Arch. Toxicol. ... More
Target molecular weights for red cell band 3 stilbene and mercurial binding sites.
AuthorsVerkman AS, Skorecki KL, Jung CY, Ausiello DA
JournalAm J Physiol
PubMed ID3020989
Radiation inactivation was used to measure the target sizes for binding of disulfonic stilbene anion transport inhibitor 4,4'-dibenzamido-2,2'-disulfonic stilbene (DBDS) and mercurial water transport inhibitor p-chloromercuribenzene sulfonate (pCMBS) to human erythrocytes. The measured target size for erythrocyte ghost acetylcholinesterase was 78 +/- 3 kDa. DBDS binding to ghost membranes was ... More
Inhibition and derivatization of the renal Na,K-ATPase by dihydro-4,4'-diisothiocyanatostilbene-2,2'-disulfonate.
AuthorsPedemonte CH, Kaplan JH
JournalBiochemistry
PubMed ID2849997
Treatment of purified renal Na,K-ATPase with dihydro-4,4'-diisothiocyanatostilbene-2,2'-disulfonate (H2DIDS) produces both reversible and irreversible inhibition of the enzyme activity. The reversible inhibition is unaffected by the presence of saturating concentrations of the sodium pump ligands Na+,K+, Mg2+, and ATP, while the inactivation is prevented by either ATP or K+. The kinetics ... More
Sodium-dependent chloride transport in basolateral membrane vesicles isolated from rabbit proximal tubule.
AuthorsChen PY, Verkman AS
JournalBiochemistry
PubMed ID3349054
The mechanisms for Cl transport across basolateral membrane vesicles (BLMV) isolated from rabbit renal cortex were examined by using the Cl-sensitive fluorescent indicator 6-methoxy-N-(3-sulfopropyl)quinolinium (SPQ). The transporters studied included Cl/base exchange, Cl/base/Na cotransport, K/Cl cotransport, and Cl conductance. Initial rates of chloride influx (JCl) were determined from the measured time ... More
Inhibition of the anion permeability of sarcoplasmic reticulum vesicles by some stilbene derivatives.
AuthorsKasai M
JournalJ Biochem (Tokyo)
PubMed ID7287647
This paper concerns a study of the inhibition of sulfate permeability of sarcoplasmic reticulum vesicles by stilbene derivatives, such as 4-acetoamido-4'-isothiocyano-2,2'-stilbene-disulfonic acid (SITS), 4,4'-diisothiocyano-stilbene-2,2'-disulfonic acid (DIDS), and diisothiocyano-1,2-diphenyl-ethane-2,2'-disulfonic acid (H2DIDS). The level of sulfate permeability was measured by using a radioactive tracer. The sulfate efflux curves comprise two phases. This ... More
Progressive inactivation of plasma membrane (Ca2++Mg2+)ATPase by Cd2+ in the absence of ATP and reversible inhibition during catalysis.
AuthorsToledo-Maciel A, Gonçalves-Gomes S, de Gouveia Castex M, Vieyra A
JournalBiochemistry
PubMed ID9799486
The influence of Cd2+ ions on plasma membrane (Ca2++Mg2+)ATPase activity from red cells was investigated. When the membranes were preincubated with Cd2+ in the absence of ATP, basal (Ca2++Mg2+)ATPase activity (no calmodulin) was slowly and irreversibly inhibited (inactivated) following first-order kinetics (k/Ki = 0.0057 microM-1 min-1 at [Cd2+] = 0.25-1 ... More
An increase in intracellular pH during neural induction in Xenopus.
AuthorsSater AK, Alderton JM, Steinhardt RA
JournalDevelopment
PubMed ID8149919
In this paper, we show that an intracellular alkalinization of the dorsal ectoderm cells is among the earliest responses to neural induction in Xenopus. Planar explants of the dorsal marginal zone were prepared from embryos that had been microinjected during cleavage stages with the fluorescent pH indicator bis-carboxyethyl-carboxyfluorescein-dextran (BCECF-dextran), and ... More
Regulation of intracellular pH in resting and in stimulated parietal cells.
AuthorsParadiso AM, Townsley MC, Wenzl E, Machen TE
JournalAm J Physiol
PubMed ID2476937
Microspectrofluorimetry of the pH-sensitive, fluorescent dye 2',7'-biscarboxyethyl-5 (6)-carboxyfluorescein (BCECF) was used to measure intracellular pH (pHi) in single parietal cells (PC) of intact rabbit gastric glands during resting and stimulated conditions. In 61% of PC, histamine plus isobutylmethylxanthine (IBMX) (both 100 microM) caused a small increase in pHi, ranging from ... More
External anions regulate stilbene-sensitive proton transport in placental brush border vesicles.
AuthorsCabrini G, Illsley NP, Verkman AS
JournalBiochemistry
PubMed ID3024705
The mechanism for HCO3-(-)independent proton permeability in microvillus membrane vesicles (MVV) isolated from human placenta was examined by using the entrapped pH indicator 6-carboxyfluorescein (6CF). Proton fluxes (JH) across MVV were determined in response to induced pH and anion gradients from the time course of 6CF fluorescence, the MVV buffer ... More
Mechanism of anion exchange across the red cell membrane by band 3: interactions between stilbenedisulfonate and NAP-taurine binding sites.
AuthorsMacara IG, Cantley LC
JournalBiochemistry
PubMed ID7295699
Anion exchange across the erythrocyte membrane can be inhibited competitively by stilbenedisulfonates, which bind to the external transport of the band 3 protein, and noncompetitively by external NAP-taurine [2-[N-(4-azido-2-nitrophenyl)amino]ethanesulfonate], which it has been suggested binds to a "modifier site" [Knauf, P. A., Ship. S., Breur, W., MCCulloch, L., & Rothstein, ... More
Effects on water diffusion of inhibitors affecting various transport processes in human red blood cells.
AuthorsBenga G, Popescu O, Pop VI, Hodor P, Borza T
JournalEur J Cell Biol
PubMed ID1468442
The water permeability of human red blood cells has been monitored by nuclear magnetic resonance (NMR) following exposure to inhibitors of various transport processes across their membranes. No significant inhibition of water diffusion could be detected after the treatment of red blood cells with the anion exchange transport inhibitor dihydro-4,4'-diisothiocyano-stilbene-2,2'-disulfonate ... More
Renal basolateral membrane anion transporter characterized by a fluorescent disulfonic stilbene.
AuthorsChen PY, Verkman AS
JournalJ Membr Biol
PubMed ID2448466
The fluorescence enhancement of 4,4'-dibenzamido-2,2'-disulfonic stilbene (DBDS) upon binding to membranes was used to examine proximal tubule stilbene binding sites. Equilibrium binding studies of DBDS to renal brush border (BBMV) and basolateral membrane vesicles (BLMV) were performed using a fluorescence enhancement technique developed for red blood cells (A.S. Verkman, J.A. ... More
Enzymatic deglycosylation of human Band 3, the anion transport protein of the erythrocyte membrane. Effect on protein structure and transport properties.
AuthorsCasey JR, Pirraglia CA, Reithmeier RA
JournalJ Biol Chem
PubMed ID1601863
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 ... More
Inhibition of inorganic anion transport across the human red blood cell membrane by chloride-dependent association of dipyridamole with a stilbene disulfonate binding site on the band 3 protein.
AuthorsLegrum B, Passow H
JournalBiochim Biophys Acta
PubMed ID2923878
The inhibition of inorganic anion transport by dipyridamole (2,6-bis(diethanolamino)-4,8-dipiperidinopyrimido[5,4-d] pyrimidine) takes place only in the presence of Cl-, other halides, nitrate or bicarbonate. At any given dipyridamole concentration, the anion flux relative to the flux in the absence of dipyridamole follows the equation: Jrel = (1 + alpha 2[Cl-])/(1 + ... More
Enhancement of anion equilibrium exchange by dansylation of the red blood cell membrane.
AuthorsLegrum B, Fasold H, Passow H
JournalHoppe Seylers Z Physiol Chem
PubMed ID7450677
Dansylation of resealed red cell ghosts enhances the band 3 protein-mediated equilibrium exchange of sulfate ions. After dansylation, the specific anion transport inhibitor 4,4'-diisothiocyanato-dihydrostilbene 2,2'-disulfonate (H2DIDS) is still capable of combining with its original binding site on the band 3 protein and of producing the same high degree of inhibition ... More
Glutamic acid 472 and lysine 480 of the sodium pump alpha 1 subunit are essential for activity. Their conservation in pyrophosphatases suggests their involvement in recognition of ATP phosphates.
AuthorsScheiner-Bobis G, Schreiber S
JournalBiochemistry
PubMed ID10413494
P-type ATPases such as the Na+,K+-ATPase (sodium pump) hydrolyze ATP to pump ions through biological membranes against their electrochemical gradients. The mechanisms that couple ATP hydrolysis to the vectorial ion transport are not yet understood, but unveiling structures that participate in ATP binding and in the formation of the ionophore ... More
Inhibition of mouse erythroid band 3-mediated chloride transport by site-directed mutagenesis of histidine residues and its reversal by second site mutation of Lys 558, the locus of covalent H2DIDS binding.
AuthorsMüller-Berger S, Karbach D, König J, Lepke S, Wood PG, Appelhans H, Passow H
JournalBiochemistry
PubMed ID7626600
Substitution by site-directed mutagenesis of any one of the histidine residues H721, H837, and H852 by glutamine, or of H752 by serine, inhibits Cl- flux mediated by band 3 expressed in Xenopus oocytes. Mutation of Lys 558 (K558N), the site of covalent binding of H2DIDS (4,4'-diisothiocyanostilbene-2,2'-disulfonate) in the outer membrane ... More
The role of intracellular alkalinization in the establishment of anterior neural fate in Xenopus.
AuthorsUzman JA, Patil S, Uzgare AR, Sater AK
JournalDev Biol
PubMed ID9466884
Our previous work demonstrated that Xenopus ectoderm cells undergo an alkalinization in response to planar inductive signals during neural induction in explants. We have examined the role of intracellular alkalinization in the establishment of anterior neural fate. First, RT-PCR was used to examine neural-specific gene expression in planar explants in ... More
Expression, localization, and functional evaluation of CFTR in bovine corneal endothelial cells.
AuthorsSun XC, Bonanno JA
JournalAm J Physiol Cell Physiol
PubMed ID11880256
HCO-dependent fluid secretion by the corneal endothelium controls corneal hydration and maintains corneal transparency. Recently, it has been shown that mRNA for the cystic fibrosis transmembrane conductance regulator (CFTR) is expressed in the corneal endothelium; however, protein expression, functional localization, and a possible role in HCO transport have not been ... More
Carbon dioxide permeability of aquaporin-1 measured in erythrocytes and lung of aquaporin-1 null mice and in reconstituted proteoliposomes.
AuthorsYang B, Fukuda N, van Hoek A, Matthay MA, Ma T, Verkman AS
JournalJ Biol Chem
PubMed ID10644730
Measurements of CO(2) permeability in oocytes and liposomes containing water channel aquaporin-1 (AQP1) have suggested that AQP1 is able to transport both water and CO(2). We studied the physiological consequences of CO(2) transport by AQP1 by comparing CO(2) permeabilities in erythrocytes and intact lung of wild-type and AQP1 null mice. ... More
Transport of long-chain native fatty acids across human erythrocyte ghost membranes.
AuthorsKleinfeld AM, Storms S, Watts M
JournalBiochemistry
PubMed ID9609694
Evidence from a number of laboratories suggests that membrane proteins may meditate the transport of physiologic fatty acids (FA) across cell membranes. However, actual transport of unbound free fatty acids (unbound FFA) from the aqueous phase on one side of a cell membrane to the aqueous phase on the other ... More
pH-dependence of inhibition by H2DIDS of mouse erythroid band 3-mediated Cl- transport in Xenopus oocytes. The effect of oligonucleotide-directed replacement of Lys-558 by an Asn residue.
AuthorsKietz D, Bartel D, Lepke S, Passow H
JournalBiochim Biophys Acta
PubMed ID1902748
The rapid reversible inhibition of band 3-mediated inorganic anion transport by 4,4'-diisothiocyanodihydrostilbene-2,2'-disfulfonate (H2DIDS) turns slowly into irreversible inhibition. This is due to covalent bond formation of the two isothiocyanate groups of the inhibitor with two lysine residues on band 3, called Lys a and Lys b. In the red cell ... More
Intracellular pH regulation in fresh and cultured bovine corneal endothelium. II. Na+:HCO3- cotransport and Cl-/HCO3- exchange.
AuthorsBonanno JA, Giasson C
JournalInvest Ophthalmol Vis Sci
PubMed ID1399410
The comparison of intracellular pH (pHi) regulation between fresh (FBCE) and cultured (CBCE) bovine corneal endothelium was extended to HCO3- transport mechanisms. Upon introduction of CO2/HCO3- Ringer's solution, there was a small, sharp acidification followed by an alkalinization .09 and .18 pH U above the HCO3- free resting pHi for ... More
Hormonal regulation of the polarized function and distribution of Na/H exchange and Na/HCO3 cotransport in cultured mammary epithelial cells.
AuthorsSjaastad MD, Zettl KS, Parry G, Firestone GL, Machen TE
JournalJ Cell Biol
PubMed ID8393012
The time course for development of polarized function and morphological distribution of pH regulatory mechanisms has been examined in a mouse mammary epithelial cell line (31EG4). Monolayers grown on permeable supports had tight junctions when grown 3-4 days in the presence of the lactogenic hormones dexamethasone (D, a synthetic glucocorticoid) ... More
Reabsorption of dicarboxylic acids from the proximal convolution of rat kidney.
AuthorsSheridan E, Rumrich G, Ullrich KJ
JournalPflugers Arch
PubMed ID6646996
The transport of dicarboxylic acid in the late proximal convolution was investigated by measuring the 3.5 s efflux of 2-oxoglutarate from the tubular lumen of rats starved for 3 days. The 3.5 s efflux of 2-oxoglutarate comprises two components, one due to movement across the brush border, obeying Michaelis Menten ... More
Intracellular pH and multidrug resistance regulate complement-mediated cytotoxicity of nucleated human cells.
AuthorsWeisburg JH, Roepe PD, Dzekunov S, Scheinberg DA
JournalJ Biol Chem
PubMed ID10196165
In previous work (Weisburg, J. H., Curcio, M., Caron, P. C., Raghi, G., Mechetner, E. B., Roepe, P. D., and Scheinberg, D. A. (1996) J. Exp. Med. 183, 2699-2704), we showed that multidrug resistance (MDR) cells created by continuous selection with the vinca alkaloid vincristine (HL60 RV+) or by retroviral ... More
H+ transporters in the main excretory duct of the mouse mandibular salivary gland.
AuthorsChaturapanich G, Ishibashi H, Dinudom A, Young JA, Cook DI
JournalJ Physiol
PubMed ID9379413
1. We used microspectrofluorimetry with the pH-sensitive fluoroprobe 2',7'-bis(2-carboxyethyl)-5(and-6)-carboxyfluorescein (BCECF) to study the regulation of cytosolic pH (pHi) in the isolated, perfused main excretory duct of the mouse mandibular gland. 2. In nominally HCO3(-)-free solutions, removal of Na+ from the lumen alone caused pHi to decline whereas removing it from ... More
Expression and trans-synaptic regulation of P2x4 and P2z receptors for extracellular ATP in parotid acinar cells. Effects of parasympathetic denervation.
AuthorsTenneti L, Gibbons SJ, Talamo BR
JournalJ Biol Chem
PubMed ID9756924
Trans-synaptic regulation of muscarinic, peptidergic, and purinergic responses after denervation has been reported previously in rat parotid acinar cells (McMillian, M. K., Soltoff, S. P., Cantley, L. C., Rudel, R., and Talamo, B. R. (1993) Br. J. Pharmacol. 108, 453-461). Characteristics of the ATP-mediated responses and the effects of parasympathetic ... More
Binding properties of the stilbene disulfonate sites on human erythrocyte AE1: kinetic, thermodynamic, and solid state deuterium NMR analyses.
AuthorsTaylor AM, Gröbner G, Williamson PT, Watts A
JournalBiochemistry
PubMed ID10460174
A novel stilbene disulfonate, 4-trimethylammonium-4'-isothiocyanostilbene-2,2'-disulfonic acid (TIDS), has been chemically synthesized, and the interaction of this probe with human erythrocyte anion exchanger (AE1) was characterized. Covalent labeling of intact erythrocytes by [N(+)((14)CH(3))(3)]TIDS revealed that specific modification of AE1 was achieved only after removal of other ligand binding sites by external ... More