Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
2001-5-25
pubmed:databankReference
pubmed:abstractText
The effect of the familial hypertrophic cardiomyopathy mutations, A13T, F18L, E22K, R58Q, and P95A, found in the regulatory light chains of human cardiac myosin has been investigated. The results demonstrate that E22K and R58Q, located in the immediate extension of the helices flanking the regulatory light chain Ca(2+) binding site, had dramatically altered Ca(2+) binding properties. The K(Ca) value for E22K was decreased by approximately 17-fold compared with the wild-type light chain, and the R58Q mutant did not bind Ca(2+). Interestingly, Ca(2+) binding to the R58Q mutant was restored upon phosphorylation, whereas the E22K mutant could not be phosphorylated. In addition, the alpha-helical content of phosphorylated R58Q greatly increased with Ca(2+) binding. The A13T mutation, located near the phosphorylation site (Ser-15) of the human cardiac regulatory light chain, had 3-fold lower K(Ca) than wild-type light chain, whereas phosphorylation of this mutant increased the Ca(2+) affinity 6-fold. Whereas phosphorylation of wild-type light chain decreased its Ca(2+) affinity, the opposite was true for A13T. The alpha-helical content of the A13T mutant returned to the level of wild-type light chain upon phosphorylation. The phosphorylation and Ca(2+) binding properties of the regulatory light chain of human cardiac myosin are important for physiological function, and alteration any of these could contribute to the development of hypertrophic cardiomyopathy.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
9
pubmed:volume
276
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
7086-92
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:11102452-Amino Acid Sequence, pubmed-meshheading:11102452-Animals, pubmed-meshheading:11102452-Binding Sites, pubmed-meshheading:11102452-Calcium, pubmed-meshheading:11102452-Cardiomyopathy, Hypertrophic, pubmed-meshheading:11102452-Circular Dichroism, pubmed-meshheading:11102452-DNA, Complementary, pubmed-meshheading:11102452-Electrophoresis, Polyacrylamide Gel, pubmed-meshheading:11102452-Humans, pubmed-meshheading:11102452-Kinetics, pubmed-meshheading:11102452-Models, Molecular, pubmed-meshheading:11102452-Molecular Sequence Data, pubmed-meshheading:11102452-Mutation, pubmed-meshheading:11102452-Myosin Light Chains, pubmed-meshheading:11102452-Phosphorylation, pubmed-meshheading:11102452-Protein Binding, pubmed-meshheading:11102452-Protein Isoforms, pubmed-meshheading:11102452-Protein Structure, Secondary
pubmed:year
2001
pubmed:articleTitle
Familial hypertrophic cardiomyopathy mutations in the regulatory light chains of myosin affect their structure, Ca2+ binding, and phosphorylation.
pubmed:affiliation
Department of Molecular and Cellular Pharmacology, University of Miami School of Medicine, Miami, Florida 33136, USA. dszczesna@med.miami.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't