Linked Life Data

6487594

Source:http://linkedlifedata.com/resource/pubmed/id/6487594

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
18
pubmed:dateCreated
1984-12-12
pubmed:abstractText
The ATPase activity of acto-myosin subfragment 1 (S-1) was measured in the presence of smooth and skeletal muscle tropomyosins over a wide range of ionic strengths (20-120 mM). In contrast to the 60% inhibitory effect caused by skeletal muscle tropomyosin at all ionic strengths, the effect of smooth muscle tropomyosin was found to be dependent on ionic strength. At low ionic strength (20 mM), smooth muscle tropomyosin inhibits the ATPase activity by 60%, while at high ionic strength (120 mM), it potentiates the ATPase activity 3-fold. All of these ATPase activities were measured at very low ratios of S-1 to actin, under conditions at which a 4-fold increase in S-1 concentration did not change the specific activity of the tropomyosin-acto.S-1 ATPase. Therefore, the potentiation of the ATPase activity by smooth muscle tropomyosin at high ionic strength cannot be explained by bound S-1 heads cooperatively turning on the tropomyosin-actin complex. To determine whether the fully potentiated rates are different in the presence of smooth muscle and skeletal muscle tropomyosins, S-1 which was extensively modified by N-ethylmaleimide was added to the ATPase assay to attain high ratios of S-1 to actin. The results showed that, under all conditions, the fully potentiated rates are the same for both tropomyosins.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
28
pubmed:volume
23
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4150-5
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
Comparison of effects of smooth and skeletal muscle tropomyosins on interactions of actin and myosin subfragment 1.
pubmed:publicationType
Journal Article