Linked Life Data

20018171

Source:http://linkedlifedata.com/resource/pubmed/id/20018171

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2010-2-23
pubmed:abstractText
Lysenin is a self-assembling, pore-forming toxin which specifically recognizes sphingomyelin. Mutation of tryptophan 20 abolishes lysenin oligomerization and cytolytic activity. We studied the interaction of lysenin WT and W20A with sphingomyelin in membranes of various lipid compositions which, according to atomic force microscopy studies, generated either homo- or heterogeneous sphingomyelin distribution. Liposomes composed of SM/DOPC, SM/DOPC/cholesterol and SM/DPPC/cholesterol could bind the highest amounts of GST-lysenin WT, as shown by surface plasmon resonance analysis. These lipid compositions enhanced the release of carboxyfluorescein from liposomes induced by lysenin WT, pointing to the importance of heterogeneous sphingomyelin distribution for lysenin WT binding and oligomerization. Lysenin W20A bound more weakly to sphingomyelin-containing liposomes than did lysenin WT. The same amounts of lysenin W20A bound to sphingomyelin mixed with either DOPC or DPPC, indicating that the binding was not affected by sphingomyelin distribution in the membranes. The mutant lysenin had a limited ability to penetrate hydrophobic region of the membrane as indicated by measurements of surface pressure changes. When applied to detect sphingomyelin on the cell surface, lysenin W20A formed large conglomerates on the membrane, different from small and regular clusters of lysenin WT. Only lysenin WT recognized sphingomyelin pool affected by formation of raft-based signaling platforms. During fractionation of Triton X-100 cell lysates, SDS-resistant oligomers of lysenin WT associated with membrane fragments insoluble in Triton X-100 while monomers of lysenin W20A partitioned to Triton X-100-soluble membrane fractions. Altogether, the data suggest that oligomerization of lysenin WT is a prerequisite for its docking in raft-related domains.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0006-3002
pubmed:author
pubmed:copyrightInfo
Copyright 2009 Elsevier B.V. All rights reserved.
pubmed:issnType
Print
pubmed:volume
1798
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
471-81
pubmed:meshHeading
pubmed-meshheading:20018171-Adsorption, pubmed-meshheading:20018171-Cell Line, pubmed-meshheading:20018171-Detergents, pubmed-meshheading:20018171-Humans, pubmed-meshheading:20018171-Kinetics, pubmed-meshheading:20018171-Liposomes, pubmed-meshheading:20018171-Membrane Microdomains, pubmed-meshheading:20018171-Microscopy, Atomic Force, pubmed-meshheading:20018171-Mutant Proteins, pubmed-meshheading:20018171-Protein Binding, pubmed-meshheading:20018171-Protein Structure, Quaternary, pubmed-meshheading:20018171-Protein Transport, pubmed-meshheading:20018171-Receptors, IgG, pubmed-meshheading:20018171-Recombinant Fusion Proteins, pubmed-meshheading:20018171-Sphingomyelins, pubmed-meshheading:20018171-Surface Plasmon Resonance, pubmed-meshheading:20018171-Surface Properties, pubmed-meshheading:20018171-Toxins, Biological
pubmed:year
2010
pubmed:articleTitle
Sphingomyelin-rich domains are sites of lysenin oligomerization: implications for raft studies.
pubmed:affiliation
Department of Cell Biology, The Nencki Institute of Experimental Biology, 3 Pasteur St., 02-093 Warsaw, Poland.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't