Linked Life Data

11587548

Source:http://linkedlifedata.com/resource/pubmed/id/11587548

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2001-10-5
pubmed:abstractText
The inositol 1,4,5-trisphosphate receptor (InsP3R) is an intracellular Ca2+ release channel which upon activation initiates many cellular functions. Multiple InsP3R subtypes are expressed in most cell types but the physiological significance of this heterogeneity is poorly understood. This study has directly compared the functional properties of the three different InsP3R isoforms by analyzing their InsP3-induced Ca2+ release (IICR) properties in cell lines which predominantly express each isoform subtype. The InsP3-dependence of the amount or extent of IICR was InsP3R isoform-specific, with the type III isoform having the lowest affinity with respect to Ca2+ release. The transient kinetics of IICR, measured using stopped-flow spectrofluorimetry, however, were similar for all three InsP3R isoforms. At maximal InsP3 concentrations (20 microM) the rate constants where between 0.8 and 1.0 s(-1) for the fast phase and 0.25-0.45 s(-1) for the slow phase. The concentration of InsP3 required to induce half-maximal rates of Ca2+ release (EC50) were also similar for the three isoforms (0.2-0.4 microM for the fast phase and 0.75-0.95 microM for the slow phase). These results indicate the InsP3R channel does not significantly differ functionally in terms of Ca2+ release rates between isoforms. The temporal and spatial features of intracellular Ca2+ signals are thus probably achieved through InsP3R isoform-specific regulation or localization rather than their intrinsic Ca2+ efflux properties.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0143-4160
pubmed:author
pubmed:copyrightInfo
Copyright 2001 Harcourt Publishers Ltd.
pubmed:issnType
Print
pubmed:volume
30
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
245-50
pubmed:dateRevised
2007-7-18
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Inositol 1,4,5-trisphosphate receptor isoforms show similar Ca2+ release kinetics.
pubmed:affiliation
School of Biosciences, University of Birmingham, Edgbaston, Birmingham, UK.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't