Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
37
pubmed:dateCreated
1999-10-7
pubmed:abstractText
A sequence motif, GXRXGGGXGD, located in the putative channel-forming domain, is conserved in all known ryanodine receptors and inositol 1,4,5-trisphosphate receptors. The functional significance of this conserved region was investigated by using site-directed mutagenesis together with functional assays consisting of Ca(2+) release measurements, [(3)H]ryanodine binding, and single channel recordings in planar lipid bilayers. We report here that single point mutations introduced into this region of the mouse cardiac ryanodine receptor reduce or abolish high affinity [(3)H]ryanodine binding. Single channel analysis revealed that a single substitution of alanine for glycine 4824 within this region reduced the single channel conductance by 97%, from 798 picosiemens (pS) for the wild type channel to 22 pS. The G4824A mutant channel was modulated by Ca(2+), Mg(2+), ATP, caffeine, ruthenium red, and ryanodine. Co-expression of the wild type and G4824A mutant proteins produced single channels that have intermediate unitary conductances of 516, 256, 176, and 60 pS. These data suggest that this conserved region constitutes an essential part of the ryanodine binding site and the channel conduction pathway of the ryanodine receptor.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
10
pubmed:volume
274
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
25971-4
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Molecular identification of the ryanodine receptor pore-forming segment.
pubmed:affiliation
Cardiovascular Research Group, Department of Physiology, University of Calgary, Calgary, Alberta T2N 4N1, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't