Linked Life Data

21664913

Source:http://linkedlifedata.com/resource/pubmed/id/21664913

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2011-7-25
pubmed:abstractText
The calmodulin (CaM) hypothesis of ectodomain shedding stipulates that CaM, an intracellular Ca²?-dependent regulatory protein, associates with the cytoplasmic domain of L-selectin to regulate ectodomain shedding of L-selectin on the other side of the plasma membrane. To understand the underlying molecular mechanism, we have characterized the interactions of CaM with two peptides derived from human L-selectin. The peptide ARR18 corresponds to the entire cytoplasmic domain of L-selectin (residues Ala317-Tyr334 in the mature protein), and CLS corresponds to residues Lys280-Tyr334, which contains the entire transmembrane and cytoplasmic domains of l-selectin. Monitoring the interaction by fluorescence spectroscopy and other biophysical techniques, we found that CaM can bind to ARR18 in aqueous solutions or the L-selectin cytoplasmic domain of CLS reconstituted in the phosphatidylcholine bilayer, both with an affinity of approximately 2 ?M. The association is calcium independent and dynamic and involves both lobes of CaM. In a phospholipid bilayer, the positively charged L-selectin cytoplasmic domain of CLS is associated with anionic phosphatidylserine (PS) lipids at the membrane interface through electrostatic interactions. Under conditions where the PS content mimics that in the inner leaflet of the cell plasma membrane, the interaction between CaM and CLS becomes undetectable. These results suggest that the association of CaM with L-selectin in the cell can be influenced by the membrane bilayer and that anionic lipids may modulate ectodomain shedding of transmembrane receptors.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
1089-8638
pubmed:author
pubmed:copyrightInfo
Copyright © 2011 Elsevier Ltd. All rights reserved.
pubmed:issnType
Electronic
pubmed:day
5
pubmed:volume
411
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
220-33
pubmed:dateRevised
2011-9-26
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Interaction of calmodulin with L-selectin at the membrane interface: implication on the regulation of L-selectin shedding.
pubmed:affiliation
Center for Membrane Biology, Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural