Show simple item record

dc.contributor.authorSmolen, James E.en_US
dc.contributor.authorBrock, Thomas G.en_US
dc.contributor.authorMargolis, D. I.en_US
dc.contributor.authorNagaprakash, K.en_US
dc.date.accessioned2006-09-11T19:40:14Z
dc.date.available2006-09-11T19:40:14Z
dc.date.issued1994-08en_US
dc.identifier.citationBrock, T. G.; Nagaprakash, K.; Margolis, D. I.; Smolen, J. E.; (1994). "Modeling degranulation with liposomes: Effect of lipid composition on membrane fusion." The Journal of Membrane Biology 141(2): 139-148. <http://hdl.handle.net/2027.42/48023>en_US
dc.identifier.issn0022-2631en_US
dc.identifier.issn1432-1424en_US
dc.identifier.urihttps://hdl.handle.net/2027.42/48023
dc.identifier.urihttp://www.ncbi.nlm.nih.gov/sites/entrez?cmd=retrieve&db=pubmed&list_uids=7807516&dopt=citationen_US
dc.description.abstractDegranulation involves the regulated fusion of granule membrane with plasma membrane. To study the role of lipid composition in degranulation, large unilamellar vesicles (LUVs) of increasing complexity in lipid compositions were constructed and tested for Ca 2+ -mediated lipid and contents mixing. Lipid-mixing rates of LUVs composed of phosphatidylethanolamine (PE) and phosphatidylserine (PS) were strongly decreased by the addition of either phosphatidylcholine (PC) or sphingomyelin (SM), while phosphatidylinositol (PI) had little effect. “Complex” LUVs of PC∶PE∶SM∶PI∶PS (24∶27∶20∶16∶13, designed to emulate neutrophil plasma membranes) also showed very low rates of both lipid mixing and contents mixing. The addition of cholesterol significantly lowered the Ca 2+ threshold for contents mixing and increased the maximum rates of both lipid and contents mixing in a dose-dependent manner. Membrane remodeling, which occurs in neutrophil plasma membranes upon stimulation, was simulated by incorporating low levels of phosphatidic acid (PA) or a diacylglycerol (DAG) into complex LUVs containing 50% cholesterol. The addition of PA both lowered the Ca 2+ threshold and increased the rate of contents mixing in a dose-dependent manner, while the DAG had no significant effect. The interaction of dissimilar LUVs was also examined. Contents-mixing rates of LUVs of two different cholesterol contents were intermediate between the rates observed for the LUVs of identical composition. Thus, cholesterol needed to be present in only one fusing partner to enhance fusion. However, for PA to stimulate fusion, it had to be present in both sets of LUVs. These results suggest that the rate of degranulation may be increased by a rise in the cholesterol level of either the inner face of the plasma membrane or the outer face of the granule membrane. Further, the production of PA can promote fusion, and hence degranulation, whereas the subsequent conversion of PA to DAG may reverse this promotional effect.en_US
dc.format.extent1039761 bytes
dc.format.extent3115 bytes
dc.format.mimetypeapplication/pdf
dc.format.mimetypetext/plain
dc.language.isoen_US
dc.publisherSpringer-Verlag; Springer-Verlag New York Inc.en_US
dc.subject.otherCalciumen_US
dc.subject.otherMembrane Fusionen_US
dc.subject.otherPhosphatidic Aciden_US
dc.subject.otherLiposomesen_US
dc.subject.otherBiochemistry, Generalen_US
dc.subject.otherHuman Physiologyen_US
dc.subject.otherLife Sciencesen_US
dc.subject.otherCholesterolen_US
dc.titleModeling degranulation with liposomes: Effect of lipid composition on membrane fusionen_US
dc.typeArticleen_US
dc.subject.hlbsecondlevelMolecular, Cellular and Developmental Biologyen_US
dc.subject.hlbsecondlevelGeneticsen_US
dc.subject.hlbtoplevelScienceen_US
dc.subject.hlbtoplevelHealth Sciencesen_US
dc.description.peerreviewedPeer Revieweden_US
dc.contributor.affiliationumDepartment of Pediatrics, University of Michigan Medical Center, Room 7510C MSRB I, Box 0684, 48109-0684, Ann Arbor, Michiganen_US
dc.contributor.affiliationumDepartment of Pediatrics, University of Michigan Medical Center, Room 7510C MSRB I, Box 0684, 48109-0684, Ann Arbor, Michigan; Department of Pathology, University of Michigan Medical Center, 48109-0684, Ann Arbor, Michiganen_US
dc.contributor.affiliationumDepartment of Pediatrics, University of Michigan Medical Center, Room 7510C MSRB I, Box 0684, 48109-0684, Ann Arbor, Michiganen_US
dc.contributor.affiliationumDepartment of Pediatrics, University of Michigan Medical Center, Room 7510C MSRB I, Box 0684, 48109-0684, Ann Arbor, Michiganen_US
dc.contributor.affiliationumcampusAnn Arboren_US
dc.identifier.pmid7807516en_US
dc.description.bitstreamurlhttp://deepblue.lib.umich.edu/bitstream/2027.42/48023/1/232_2004_Article_BF00238247.pdfen_US
dc.identifier.doihttp://dx.doi.org/10.1007/BF00238247en_US
dc.identifier.sourceThe Journal of Membrane Biologyen_US
dc.owningcollnameInterdisciplinary and Peer-Reviewed


Files in this item

Show simple item record