Linked Life Data

12755616

Source:http://linkedlifedata.com/resource/pubmed/id/12755616

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
20
pubmed:dateCreated
2003-5-20
pubmed:abstractText
There is no consensus on the mechanism of inhibition of actin-myosin ATPase activity by caldesmon. Various models are based on different assumptions for the number of actin monomers that constitute a caldesmon binding site. Differences in binding behavior may be due to variations in the assay, the range of caldesmon concentrations, the type of caldesmon, and the method of data analysis used. We have evaluated these factors by measuring binding in the presence and absence of tropomyosin with both intact caldesmon and a recombinant 35 kDa actin binding fragment and with actin initially in the polymerized state or monomeric state. In all cases caldesmon binding could be simulated with a model having one class of binding sites. However, the number of actin monomers constituting a site was variable. Binding to F-actin at 165 mM ionic strength was best described with 7 actin monomers per site. When caldesmon bound to actin during the polymerization of G-actin, the size of the binding site was 3. Binding of the expressed truncated fragment, Cad35, could be described with 3 monomers per site. A simple interpretation of the data is that caldesmon binds tightly to 2-3 actin monomers. Additional parts of caldesmon bind less tightly to actin, causing caldesmon to cover approximately 7 actin monomers. The appendix contains an analysis of several binding curves with multiple binding site models. There is no compelling evidence for two classes of binding sites.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
27
pubmed:volume
42
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
6136-48
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Influence of ionic strength, actin state, and caldesmon construct size on the number of actin monomers in a caldesmon binding site.
pubmed:affiliation
Department of Biochemistry and Molecular Biology, The Brody School of Medicine at East Carolina University, 600 Moye Boulevard, Greenville, North Carolina 27858-4354, USA.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't