Linked Life Data

11976941

Source:http://linkedlifedata.com/resource/pubmed/id/11976941

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
2002-4-26
pubmed:abstractText
Hypotonicity-induced Ca2+ entry is a critical signal for the normal regulatory volume decrease in human cervical cancer cells. The aim of this study was to explore the role of myosin light chain kinase (MLCK) in the regulation of hypotonicity-induced Ca2+ signalling and Cl- channel activity. Blockade of MLCK activity by MLCK(11-19) amide, a substrate-specific peptide inhibitor, markedly attenuated hypotonicity-induced Ca2+ entry. A similar result was obtained with ML-7, a synthetic naphthalenesulphonyl derivative that inhibits the binding of ATP to MLCK. More than 85% of the activity of the volume-regulated Cl- channel was suppressed when intracellular Ca2+ was buffered to near zero in the absence of extracellular Ca2+, suggesting that hypotonicity-induced Ca2+ signalling is important for the activation of the volume-regulated Cl- channel. Intracellular dialysis with MLCK(11-19) amide or ML-7 concentration-dependently reduced the amplitude and rate of activation of the volume-regulated Cl- channel. Swelling-activated taurine transport was also inhibited concentration dependently by ML-7 and MLCK(11-19) amide with IC(50) values of 6.4 and 2.0 microM, respectively. Hypotonicity induced MLC phosphorylation which was mediated totally by MLCK and depended on Ca2+ entry. However, phosphorylated MLC per se was not involved critically in the regulation of Ca2+ entry and activation of volume-sensitive organic osmolyte/anion channels (VSOAC). We propose that MLCK has a novel function in regulating the activation of VSOAC by mediating Ca2+ entry in response to hypotonicity. This function of MLCK on Ca2+ signalling does not correlate with MLC phosphorylation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0031-6768
pubmed:author
pubmed:issnType
Print
pubmed:volume
444
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
276-85
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:11976941-Algorithms, pubmed-meshheading:11976941-Antibodies, Monoclonal, pubmed-meshheading:11976941-Calcium, pubmed-meshheading:11976941-Calcium Signaling, pubmed-meshheading:11976941-Chloride Channels, pubmed-meshheading:11976941-Electric Stimulation, pubmed-meshheading:11976941-Electrophysiology, pubmed-meshheading:11976941-Female, pubmed-meshheading:11976941-Fluorescent Dyes, pubmed-meshheading:11976941-Fura-2, pubmed-meshheading:11976941-Humans, pubmed-meshheading:11976941-Hypotonic Solutions, pubmed-meshheading:11976941-Myosin-Light-Chain Kinase, pubmed-meshheading:11976941-Osmotic Pressure, pubmed-meshheading:11976941-Patch-Clamp Techniques, pubmed-meshheading:11976941-Phosphorylation, pubmed-meshheading:11976941-Taurine, pubmed-meshheading:11976941-Tumor Cells, Cultured, pubmed-meshheading:11976941-Uterine Cervical Neoplasms
pubmed:year
2002
pubmed:articleTitle
Myosin light chain kinase modulates hypotonicity-induced Ca2+ entry and Cl- channel activity in human cervical cancer cells.
pubmed:affiliation
Department of Obstetrics and Gynaecology, College of Medicine, National Cheng Kung University, Tainan 704, Taiwan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't