Ca(2+)-mobilizing hormones potentiate hypotonicity-induced activation of ionic conductances in Intestine 407 cells

1994 ◽  
Vol 267 (5) ◽  
pp. C1271-C1278 ◽  
Author(s):  
B. C. Tilly ◽  
M. J. Edixhoven ◽  
N. van den Berghe ◽  
A. G. Bot ◽  
H. R. de Jonge
Keyword(s):  
Tyrosine Phosphorylation ◽  
Regulatory Volume Decrease ◽  
Cell Types ◽  
Cell Swelling ◽  
Protein Tyrosine Phosphorylation ◽  
Acetoxymethyl Ester ◽  
Protein Tyrosine ◽  
Ionic Conductances ◽  
Cl Channels ◽  
Volume Decrease

Human Intestine 407 cells respond to hyposmotic stimulation by activating the conductive efflux of both Cl- and K+ (regulatory volume decrease) through pathways involving protein tyrosine phosphorylation (Tilly, B. C., N. van den Berghe, L. G. J. Tertoolen, M. J. Edixhoven, and H. R. de Jonge. J. Biol. Chem. 268: 19919-19922, 1993). Stimulation of the cells with hormones linked to the phospholipase C signaling cascade (e.g., bradykinin, histamine, or thrombin) or with the phosphotyrosine phosphatase inhibitor vanadate, potentiated the osmosensitive anion efflux by two- to threefold but did not affect anion efflux under isotonic conditions. No substantial increase in intracellular Ca2+ concentration ([Ca2+]i) was observed on mild hypotonicity-induced cell swelling. In addition, loading the cells with the intracellular Ca2+ chelator 1,2-bis(2-amino-phenoxy)ethane- N,N,N',N',-tetraacetic acid acetoxymethyl ester (BAPTA-AM) caused a partial reduction of the osmoshock-induced 125I- efflux but did not affect its potentiation by vanadate. In contrast, bradykinin transiently elevated [Ca2+]i, and its potentiation of the osmosensitive anion efflux was completely inhibited after BAPTA-AM loading. Both the Ca(2+)-mobilizing hormones as well as osmotic cell swelling rapidly triggered the phosphorylation of several proteins on tyrosine residues. However, the effects of the hormones, but not the effect of hypotonicity, on protein tyrosine phosphorylation was largely abolished in BAPTA-loaded cells. Taken together the results indicate a novel role for Ca(2+)-mobilizing hormones, although elevation of [Ca2+]i, in potentiating volume-sensitive ionic efflux even in cell types lacking the expression of Ca(2+)-activated Cl- channels in their plasma membrane.

Hyposmotic activation of ICl,swell in rabbit nonpigmented ciliary epithelial cells involves increased ClC-3 trafficking to the plasma membrane

2004 ◽  
Vol 82 (6) ◽  
pp. 708-718 ◽  
Author(s):  
John P Vessey ◽  
Chanjuan Shi ◽  
Christine AB Jollimore ◽  
Kelly T Stevens ◽  
Miguel Coca-Prados ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Membrane Trafficking ◽  
Kinase Inhibitor ◽  
Regulatory Volume Decrease ◽  
Membrane Dynamics ◽  
Cell Swelling ◽  
Cl Channels ◽  
Phosphoinositide 3 Kinase ◽  
Nonpigmented Ciliary Epithelial ◽  
Volume Decrease

In mammalian nonpigmented ciliary epithelial (NPE) cells, hyposmotic stimulation leading to cell swelling activates an outwardly rectifying Cl– conductance (ICl,swell), which, in turn, results in regulatory volume decrease. The aim of this study was to determine whether increased trafficking of intracellular ClC-3 Cl channels to the plasma membrane could contribute to the ICl,swell following hyposmotic stimulation. Our results demonstrate that hyposmotic stimulation reversibly activates an outwardly rectifying Cl– current that is inhibited by phorbol-12-dibutyrate and niflumic acid. Transfection with ClC-3 antisense, but not sense, oligonucleotides reduced ClC-3 expression as well as ICl,swell. Intracellular dialysis with 2 different ClC-3 antibodies abolished activation of ICl,swell. Immunofluorescence microscopy showed that hyposmotic stimulation increased ClC-3 immunoreactivity at the plasma membrane. To determine whether this increased expression of ClC-3 at the plasma membrane could be due to increased vesicular trafficking, we examined membrane dynamics with the fluorescent membrane dye FM1-43. Hyposmotic stimulation rapidly increased the rate of exocytosis, which, along with ICl,swell, was inhibited by the phosphoinositide-3-kinase inhibitor wortmannin and the microtubule disrupting agent, nocodazole. These findings suggest that ClC-3 channels contribute to ICl,swell following hyposmotic stimulation through increased trafficking of channels to the plasma membrane.Key words: ClC-3, NPE, cell swelling, membrane trafficking, ciliary body epithelium.

Cell volume regulation by the mouse zygote: mechanism of recovery from a volume increase

1997 ◽  
Vol 272 (6) ◽  
pp. C1854-C1861 ◽  
Author(s):  
D. G. Seguin ◽  
J. M. Baltz
Keyword(s):  
Regulatory Volume Decrease ◽  
Cell Volume Regulation ◽  
Cell Swelling ◽  
Channel Blockers ◽  
Volume Increase ◽  
K Channels ◽  
Cl Channel ◽  
Cl Channels ◽  
Mouse Zygotes ◽  
Volume Decrease

Mouse zygotes regulate their volumes after cell swelling. This regulatory volume decrease (RVD) is rapid and complete. RVD in zygotes was inhibited by K+ or Cl- channel blockers, indicating the participation of such channels in volume recovery. The channels are separate entities, as indicated by the ability of the cation ionophore gramicidin to restore RVD when K+ channels are blocked but not when Cl- channels are blocked. Intracellular Ca2+ concentration increased with cell swelling. Nevertheless, RVD occurred normally in zygotes loaded with the Ca2+ chelator, 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid, which prevented Ca2+ from increasing above its normal resting concentration. Thus an increase in intracellular Ca2+ is not necessary for zygote RVD; consistent with this, inhibitors of Ca(2+)-activated K+ channels had little or no effect on RVD. RVD in zygotes was also completely inhibited by millimolar amounts of extracellular ATP. ATP has been shown to inhibit current passed by the volume-sensitive organic osmolyte-Cl- channel in other cells, and thus zygotes may have such a channel participating in RVD.

Mechanisms of regulatory volume decrease in nonpigmented human ciliary epithelial cells

1995 ◽  
Vol 268 (3) ◽  
pp. C721-C731 ◽  
Author(s):  
J. S. Adorante ◽  
P. M. Cala
Keyword(s):  
Regulatory Volume Decrease ◽  
Cell Swelling ◽  
Ciliary Epithelium ◽  
Channel Blockers ◽  
Tetraacetic Acid ◽  
Acetoxymethyl Ester ◽  
Osmotic Swelling ◽  
Ion Efflux ◽  
Volume Recovery ◽  
Volume Decrease

To study the net solute and water efflux pathways of the ciliary epithelium we employed a cultured human NPE cell line. Because of the possible relationship between transepithelial ion and water flux and cell volume regulation, the ion efflux pathways mediating regulatory volume decrease (RVD) were investigated. Osmotic swelling of NPE cells was followed by a volume recovery. Volume recovery was K+ dependent and inhibited by K+ channel blockers such as quinine (1 mM). After osmotic swelling, a Cl(-)-dependent membrane depolarization occurred that was inhibited by Cl- channel blockers such as 5-nitro-2-(3-phenylpropylamino)benzoic acid (100 microM) or Ca2+ chelators such as ethylene glycolbis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA, 2.0 mM). Cell swelling was also accompanied by an increase in intracellular Ca2+ concentration ([Ca2+]i) of approximately 200 nM. The swelling-induced rise in [Ca2+]i and RVD were diminished in the presence of 10 microM La3+, 50 nM 12-O-tetradecanoylphorbol 13-acetate, and nominally Ca(2+)-free medium. Near total blockage of RVD occurred after pretreatment of NPE cells with Ca(2+)-free EGTA-1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA) acetoxymethyl ester-containing solutions. The inhibition of RVD by EGTA-BAPTA treatment was overcome by increasing K+ conductance with gramicidin. The above findings indicate that RVD in NPE cells is mediated by separate K+ and Cl- conductances (channels). These data also show that swelling-induced increases in [Ca2+]i help modulate net ion efflux during regulation.

scholarly journals Protein tyrosine phosphorylation is involved in osmoregulation of ionic conductances.

1993 ◽  
Vol 268 (27) ◽  
pp. 19919-19922
Author(s):  
B.C. Tilly ◽  
N van den Berghe ◽  
L.G. Tertoolen ◽  
M.J. Edixhoven ◽  
H.R. de Jonge
Keyword(s):  
Tyrosine Phosphorylation ◽  
Protein Tyrosine Phosphorylation ◽  
Protein Tyrosine ◽  
Ionic Conductances

scholarly journals Inhibitory and Transport Mechanisms of the Human Cation-Chloride Cotransport KCC1

2020 ◽  
Author(s):  
Yongxiang Zhao ◽  
Jiemin Shen ◽  
Qinzhe Wang ◽  
Ming Zhou ◽  
Erhu Cao
Keyword(s):  
Small Molecule ◽  
Transmembrane Helix ◽  
Regulatory Volume Decrease ◽  
Cell Types ◽  
Cell Swelling ◽  
Intracellular Loop ◽  
Open Conformation ◽  
Molecule Inhibitor ◽  
Cation Chloride Cotransporters ◽  
Volume Decrease

SummarySecondary active cation-chloride cotransporters (CCCs) catalyze electroneutral symport of Cl− with Na+ and/or K+ across membranes1,2. CCCs are fundamental in cell volume homeostasis, transepithelia ion movement, maintenance of intracellular Cl− concentration, and inhibitory synaptic transmission3–6. K+-Cl− cotransport 1 (KCC1) was first characterized in red blood cells and later in many other cell types as a crucial player in regulatory volume decrease in defense against cell swelling upon hypotonic challenges7,8. Here we present two cryo-EM structures of human KCC1: one captured in an inward-open state and another arrested in an outward-open state by a small molecule inhibitor. KCC1 can surprisingly adopt two distinct dimeric architectures via homotypic association of different protein domains and conversion between these two forms of dimers may entail dynamic formation and rupture of two interdigitating regulatory cytoplasmic domains. The inhibitor wedges into and forces open an extracellular ion permeation path and arrests KCC1 in an outward-open conformation. Concomitantly, the outward-open conformation involves inward movement of the transmembrane helix 8 and occlusion of the intracellular exit by a conserved short helix within the intracellular loop 1. Our structures provide a blueprint for understanding the mechanisms of CCC transporters and their inhibition by small molecule compounds.

scholarly journals The role of protein tyrosine phosphorylation in integrin-mediated gene induction in monocytes.

1994 ◽  
Vol 126 (6) ◽  
pp. 1585-1593 ◽  
Author(s):  
T H Lin ◽  
A Yurochko ◽  
L Kornberg ◽  
J Morris ◽  
J J Walker ◽  
...  
Keyword(s):  
Cell Adhesion ◽  
Tyrosine Kinase ◽  
Tyrosine Phosphorylation ◽  
Kinase Inhibitors ◽  
Cell Types ◽  
Gene Induction ◽  
Protein Tyrosine Phosphorylation ◽  
Protein Tyrosine ◽  
Dose Dependent Fashion ◽  
Beta 1 Integrin

Integrin-mediated cell adhesion, or cross-linking of integrins using antibodies, often results in the enhanced tyrosine phosphorylation of certain intracellular proteins, suggesting that integrins may play a role in signal transduction processes. In fibroblasts, platelets, and carcinoma cells, a novel tyrosine kinase termed pp125FAK has been implicated in integrin-mediated tyrosine phosphorylation. In some cell types, integrin ligation or cell adhesion has also been shown to result in the increased expression of certain genes. Although it seems reasonable to hypothesize that integrin-mediated tyrosine phosphorylation and integrin-mediated gene induction are related, until now, there has been no direct evidence supporting this hypothesis. In the current report, we explore the relationship between integrin-mediated tyrosine phosphorylation and gene induction in human monocytes. We demonstrate that monocyte adherence to tissue culture dishes or to extracellular matrix proteins is followed by a rapid and profound increase in tyrosine phosphorylation, with the predominant phosphorylated component being a protein of 76 kD (pp76). Tyrosine phosphorylation of pp76 and other monocyte proteins can also be triggered by incubation of monocytes with antibodies to the integrin beta 1 subunit, or by F(ab')2 fragments of such antibodies, but not by F(ab) fragments. The ligation of beta 1 integrins with antibodies or F(ab')2 fragments also induces the expression of immediate-early (IE) genes such as IL-1 beta. When adhering monocytes are treated with the tyrosine kinase inhibitors genistein or herbimycin, both phosphorylation of pp76 and induction of IL-1 beta message are blocked in a dose-dependent fashion. Similarly, treatment with genistein or herbimycin can block tyrosine phosphorylation of pp76 and IL-1 beta message induction mediated by ligation of beta 1 integrin with antibodies. These observations suggest that protein tyrosine phosphorylation is an important aspect of integrin-mediated IE gene induction in monocytes. The cytoplasmic tyrosine kinase pp125FAK, although important in integrin signaling in other cell types, seems not to play a role in monocytes because this protein could not be detected in these cells.

scholarly journals Angiotensin II-induced protein tyrosine phosphorylation in neonatal rat cardiac fibroblasts.

1994 ◽  
Vol 269 (30) ◽  
pp. 19626-19632
Author(s):  
W. Schorb ◽  
T.C. Peeler ◽  
N.N. Madigan ◽  
K.M. Conrad ◽  
K.M. Baker
Keyword(s):  
Angiotensin Ii ◽  
Tyrosine Phosphorylation ◽  
Cardiac Fibroblasts ◽  
Neonatal Rat ◽  
Protein Tyrosine Phosphorylation ◽  
Protein Tyrosine
Sign in / Sign up

Export Citation Format

Share Document