Show simple item record

dc.contributor.authorMossberg, Ann-Kristineng
dc.contributor.authorPuchades, Majaeng
dc.contributor.authorHalskau, Øyvindeng
dc.contributor.authorBaumann, Anneeng
dc.contributor.authorLanekoff, Ingelaeng
dc.contributor.authorChao, Yinxiaeng
dc.contributor.authorMartinez, Auroraeng
dc.contributor.authorSvanborg, Catharinaeng
dc.contributor.authorKarlsson, Rogereng
dc.date.accessioned2010-12-13T09:50:15Z
dc.date.available2010-12-13T09:50:15Z
dc.date.issued2010-01-23eng
dc.identifier.citationPLoS ONE 5(2): e9384en
dc.identifier.issn1932-6203eng
dc.identifier.urihttp://hdl.handle.net/1956/4337
dc.description.abstractBackground Cell membrane interactions rely on lipid bilayer constituents and molecules inserted within the membrane, including specific receptors. HAMLET (human α-lactalbumin made lethal to tumor cells) is a tumoricidal complex of partially unfolded α-lactalbumin (HLA) and oleic acid that is internalized by tumor cells, suggesting that interactions with the phospholipid bilayer and/or specific receptors may be essential for the tumoricidal effect. This study examined whether HAMLET interacts with artificial membranes and alters membrane structure. Methodology/Principal Findings We show by surface plasmon resonance that HAMLET binds with high affinity to surface adherent, unilamellar vesicles of lipids with varying acyl chain composition and net charge. Fluorescence imaging revealed that HAMLET accumulates in membranes of vesicles and perturbs their structure, resulting in increased membrane fluidity. Furthermore, HAMLET disrupted membrane integrity at neutral pH and physiological conditions, as shown by fluorophore leakage experiments. These effects did not occur with either native HLA or a constitutively unfolded Cys-Ala HLA mutant (rHLAall-Ala). HAMLET also bound to plasma membrane vesicles formed from intact tumor cells, with accumulation in certain membrane areas, but the complex was not internalized by these vesicles or by the synthetic membrane vesicles. Conclusions/Significance The results illustrate the difference in membrane affinity between the fatty acid bound and fatty acid free forms of partially unfolded HLA and suggest that HAMLET engages membranes by a mechanism requiring both the protein and the fatty acid. Furthermore, HAMLET binding alters the morphology of the membrane and compromises its integrity, suggesting that membrane perturbation could be an initial step in inducing cell death.en
dc.language.isoengeng
dc.publisherPublic Library of Scienceeng
dc.rightsAttribution CC BYeng
dc.rights.urihttp://creativecommons.org/licenses/by/3.0/eng
dc.titleHAMLET interacts with lipid membranes and perturbs their structure and integrityeng
dc.typePeer reviewedeng
dc.typeJournal articleeng
dc.subject.nsiVDP::Medisinske Fag: 700::Basale medisinske, odontologiske og veterinærmedisinske fag: 710::Medisinsk biokjemi: 726nob
dc.rights.holderCopyright 2010 Mossberg et al.
dc.rights.holderMossberg et al.eng
dc.type.versionpublishedVersioneng
bora.peerreviewedPeer reviewedeng
bora.cristinID340800eng
bibo.doihttp://dx.doi.org/10.1371/journal.pone.0009384eng
dc.identifier.cristinID340800eng
dc.identifier.doihttp://dx.doi.org/10.1371/journal.pone.0009384


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record

Attribution CC BY
Except where otherwise noted, this item's license is described as Attribution CC BY