Effect of modulation of protein kinase C on the cAMP‐dependent chloride conductance in T84 cells

Dechecchi, Maria Cristina; Rolfini, Rossella; Tamanini, Anna; Gamberi, Chiara; Berton, Giorgio; Cabrini, Giulio

doi:10.1016/0014-5793(92)81358-s

Cited by 29 publications

(17 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Mouse mammary carcinoma cells (c127i) transfected with human epithelial CFTR wild-type (WT1) or ⌬508 CFTR cells (34,35) were used for these studies. Cells were grown and maintained in DMEM supplemented with 10% FBS and 1% L-glutamine, as reported (35).…”

Section: Methodsmentioning

confidence: 99%

Reversal of cystic fibrosis phenotype in a cultured Δ508 cystic fibrosis transmembrane conductance regulator cell line by oligonucleotide insertion

Zamecnik

Raychowdhury

Tabatadze

et al. 2004

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Cystic fibrosis (CF) is a lethal genetic disorder that is due to mutations in the gene encoding the cAMP-activated anion CF transmembrane conductance regulator (CFTR) channel. A three-nucleotide base deletion (TTT), encoding phenylalanine in position 508 of the translatable CFTR sequence (accompanied by a C to T replacement immediately 5 to the deletion), accounts for Ϸ75% of cases of the disease. In the present study, an oligonucleotide complex (CF4 -CF6 , 2 -0-methyl RNA-unmodified RNA oligonucleotide duplex, respectively) was used to restore CFTR function by insertion of missing bases in ⌬508 CFTR mRNA from a cultured (⌬508) cell line. cAMP-activated wholecell currents and Cl ؊ transport were detected in CF4 -CF6-treated, but not control ⌬508, cells by patch-clamp and 6-methoxy-N-(3-sulfopropyl)quinolinium fluorescence (SPQ) quenching analyses, respectively. Further, the nucleotide addition in the deleted region of ⌬508 CFTR was determined after amplification by RT-PCR. Insertion of UGU and replacement of U by C immediately 5 to the deletion site in ⌬508 mRNA appear to have taken place, with phenotypic but not genotypic reversion in tissue culture of treated cells. The mechanism of insertion of nucleotides has yet to be determined.tissue culture ͉ functional restoration ͉ mRNA repair

show abstract

Section: Methodsmentioning

confidence: 99%

Reversal of cystic fibrosis phenotype in a cultured Δ508 cystic fibrosis transmembrane conductance regulator cell line by oligonucleotide insertion

Zamecnik

Raychowdhury

Tabatadze

et al. 2004

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…It has been demonstrated, using both molecular and functional approaches, that C127/CFTR wt and C127/CFTR ⌬F508 cells express normal and mutated CFTR, respectively (12).…”

Section: Methodsmentioning

confidence: 99%

Cystic Fibrosis Transmembrane Regulator Regulates Uptake of Sphingoid Base Phosphates and Lysophosphatidic Acid

Boujaoude¹,

Bradshaw-Wilder²,

Mao³

et al. 2001

Journal of Biological Chemistry

135

103

View full text Add to dashboard Cite

Sphingolipids have been implicated in the regulation of cell growth, differentiation, and programmed cell death. Sphingosine 1-phosphate (SPP) has recently emerged as an important lipid messenger and a ligand for the endothelial differentiation gene receptor family of proteins through which it mediates its biologic effects. Recent studies in Saccharomyces cerevisiae in our laboratory implicated the yeast oligomycin resistance gene (YOR1), a member of the ATP binding cassette family of proteins, in the transport of SPP. The cystic fibrosis transmembrane regulator is a unique member of the ATP binding cassette transporter family and has high homology with YOR1. We therefore set out to investigate if this member of the family can regulate SPP transport. We demonstrate that C127/cystic fibrosis transmembrane regulator (CFTR) cells, expressing wild type CFTR, exhibited significantly higher uptake of sphingosine 1-phosphate than either cells expressing a mutant CFTR C127/⌬F508 or C127/mock-transfected cells. This effect was specific, dose-dependent, and competed off by dihydrosphingosine 1-phosphate and lysophosphatidic acid. There was no difference in uptake of sphingosine, C 16 -ceramide, sphingomyelin, lysophingomyelin, phosphatidylcholine, lysophosphatidylcholine, or phosphatidic acid among the different cell lines. Pretreatment with forskolin or isobutylmethylxanthine to stimulate cAMP did not affect the uptake in any of the cell lines. Moreover, we found that mitogen-activated protein kinase activation by SPP was less responsive in C127/CFTR as compared with C127/mock-transfected cells, suggesting that uptake of SPP by CFTR may divert it from interacting with its cell surface receptors and attenuate signaling functions. Taken together, these data implicate CFTR in uptake of SPP and the related phosphorylated lipids dihydrosphingosine 1-phosphate and lysophosphatidic acid. This uptake influences the availability of SPP to modulate biologic activity via endothelial differentiation gene receptors. These studies may have important implications to cystic fibrosis.

show abstract

“…Berger et al, 1991;Welsh et al, 1992;Riordan, 1993). This epithelial Cl-channel can be phosphorylated by either PKA or PKC (Berger et al, 1993), but the functional effect of PKC activation by phorbol ester on Cl-current is often relatively small (Tabcharani et al, 1991;Dechecchi et al, 1992;Bajnath et al, 1994;McAlroy et al, 1994).…”

Section: Indications Of Ca2"-dependent Pkc Involvementmentioning

confidence: 99%

Phorbol ester activation of chloride current in guinea‐pig ventricular myocytes

Shuba

Asai

McDonald

1996

British J Pharmacology

View full text Add to dashboard Cite

1 Although earlier studies with phorbol esters indicate that protein kinase C (PKC) may be an important regulator of Cl-current (Icl) in cardiac cells, there is a need for additional quantitative data and investigation of conflicting findings. Our objectives were to measure the magnitude, time course, and concentration-dependence of Ic, activated in guinea-pig ventricular myocytes by phorbol 12-myristate 13-acetate (PMA), evaluate its PKC dependence, and examine its modification by external and internal ions. 2 The whole-cell patch clamp technique was used to apply short depolarizing and hyperpolarizing pulses to myocytes superfused with Na+-, K+-, Ca2+-free solution (36°C) and dialysed with Cs' solution. Stimulation of membrane currents by PMA (threshold < I M, EC50s 14 nM, maximal 40% increase with > 100 nM) plateaued within 6 -10 min. 3 PMA-activated current was time-independent, and suppressed by 1 mM 9-anthracenecarboxylic acid (9-AC). Its reversal potential (Erev) was sensitive to changes in the Cl-gradient, and outward rectification of the current-voltage (I-J) relationship was more pronounced with 30 mM than 140 mM Cl-dialysate. 4 The relative permeability of PMA-activated channels estimated from Frev measurements was I-> Cl > > aspartate. Channel activation was independent of external Na+.5 PMA failed to activate Ic, in myocytes pretreated with 1-(5-isoquinolinesulphonyl)-2-methylpiperazine (H-7) or dialysed with pCa 10.5 solution. Lack of response to 4cc-phorbol 12, 13-didecanoate (aPDD) was a further indication of mediation by PKC. 6 I1c induced by 2 giM forskolin was far larger than that induced by PMA, suggesting that endogenous protein kinase A is a much stronger Cl-channel activator than endogenous PKC in these myocytes. 7 The macroscopic properties of PMA-induced I1c appear to be indistinguishable from those of PKAactivated Ics. We discount stimulation of PKA by PMA as an explanation, and conclude that endogenous PKC may activate PKA-regulated Cl-channels in these myocytes.

show abstract

Effect of modulation of protein kinase C on the cAMP‐dependent chloride conductance in T84 cells

Cited by 29 publications

References 24 publications

Reversal of cystic fibrosis phenotype in a cultured Δ508 cystic fibrosis transmembrane conductance regulator cell line by oligonucleotide insertion

Reversal of cystic fibrosis phenotype in a cultured Δ508 cystic fibrosis transmembrane conductance regulator cell line by oligonucleotide insertion

Cystic Fibrosis Transmembrane Regulator Regulates Uptake of Sphingoid Base Phosphates and Lysophosphatidic Acid

Phorbol ester activation of chloride current in guinea‐pig ventricular myocytes

Contact Info

Product

Resources

About