Linked Life Data

10194382

Source:http://linkedlifedata.com/resource/pubmed/id/10194382

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
14
pubmed:dateCreated
1999-4-29
pubmed:abstractText
Catalytically important motions of the Ca-ATPase, modulated by the physical properties of surrounding membrane phospholipids, have been suggested to be rate-limiting under physiological conditions. To identify the nature of the structural coupling between the Ca-ATPase and membrane phospholipids, we have investigated the functional and structural effects resulting from the incorporation of the lysophospholipid 1-myristoyl-2-hydroxy-sn-glycerol-3-phosphocholine (LPC) into native sarcoplasmic reticulum (SR) membranes. Nonsolubilizing concentrations of LPC abolish changes in fluorescence signals associated with either intrinsic or extrinsic chromophores that monitor normal conformational transitions accompanying calcium activation of the Ca-ATPase. There are corresponding decreases in the rates of calcium transport coupled to ATP hydrolysis, suggesting that LPC may increase conformational barriers associated with catalytic function. Fluorescence anisotropy measurements of the lipid analogue 1-(4-trimethylammoniumphenyl)-6-phenyl-1,3,5-hexatriene (TMA-DPH) partitioned into SR membranes indicate that LPC does not significantly modify lipid acyl chain rotational dynamics, suggesting differences in headgroup conformation between LPC and diacylglycerol phosphatidylcholines. Complementary measurements using phosphorescence anisotropy of erythrosin isothiocyanate at Lys464 on the Ca-ATPase provide a measure of the dynamic structure of the phosphorylation domain, and indicate that LPC restricts the amplitude of rotational motion. These results suggest a structural linkage between the cytosolic phosphorylation domain and the conformation of membrane phospholipid headgroups. Thus, changes in membrane phospholipid composition can modulate membrane surface properties and affect catalytically important motions of the Ca-ATPase in a manner that suggests a role for LPC generated during signal transduction.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
6
pubmed:volume
38
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4604-12
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed-meshheading:10194382-Adenosine Triphosphate, pubmed-meshheading:10194382-Animals, pubmed-meshheading:10194382-Biological Transport, pubmed-meshheading:10194382-Calcium, pubmed-meshheading:10194382-Calcium-Transporting ATPases, pubmed-meshheading:10194382-Catalysis, pubmed-meshheading:10194382-Diphenylhexatriene, pubmed-meshheading:10194382-Fatty Acids, pubmed-meshheading:10194382-Fluorescence Polarization, pubmed-meshheading:10194382-Fluorescent Dyes, pubmed-meshheading:10194382-Hydrolysis, pubmed-meshheading:10194382-Lipid Bilayers, pubmed-meshheading:10194382-Lysophosphatidylcholines, pubmed-meshheading:10194382-Phospholipids, pubmed-meshheading:10194382-Phosphorylation, pubmed-meshheading:10194382-Protein Structure, Tertiary, pubmed-meshheading:10194382-Rabbits, pubmed-meshheading:10194382-Spectrometry, Fluorescence, pubmed-meshheading:10194382-Thermodynamics, pubmed-meshheading:10194382-Tryptophan
pubmed:year
1999
pubmed:articleTitle
Lysophosphatidylcholine modulates catalytically important motions of the Ca-ATPase phosphorylation domain.
pubmed:affiliation
Biochemistry and Biophysics Section, Department of Molecular Biosciences, University of Kansas, Lawrence 66045-2106, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.