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RESEARCH PRODUCT
CD95 death-inducing signaling complex formation and internalization occur in lipid rafts of type I and type II cells
Cesare PeschleCesare PeschleFiorenza LottiLucia Ricci-vitianiIsabella ParoliniRuggero De MariaAdriana EramoCarlo MessinaMassimo SargiacomoMatilde TodaroGiorgio StassiGiovanni Settesubject
Death Domain Receptor Signaling Adaptor ProteinsEndosomeT-Lymphocytesmedia_common.quotation_subjectImmunologyApoptosisReceptors Tumor Necrosis FactorCell LineMembrane MicrodomainsSettore MED/04 - PATOLOGIA GENERALECell Line TumorReceptorsHumansImmunology and Allergyfas ReceptorFADDInternalizationLipid raftLipid raftsDeath domainmedia_commonTumorbiologyVesicleFas receptorEndocytosisCell biologyProtein TransportCholesterolCD95 death-inducing signaling complexCaspasesCD95biology.proteinlipids (amino acids peptides and proteins)biological phenomena cell phenomena and immunityCaspase-8Tumor Necrosis FactorCaspase-8; CD95; Lipid rafts; Apoptosis; Caspases; Cell Line Tumor; Cholesterol; Death Domain Receptor Signaling Adaptor Proteins; Humans; Membrane Microdomains; Protein Binding; Protein Transport; Receptors Tumor Necrosis Factor; T-Lymphocytes; fas Receptor; Endocytosis; Signal Transduction; Immunology and Allergy; ImmunologyProtein BindingSignal Transductiondescription
We investigated the membrane localization of CD95 in type I and type II cells, which differ in their ability to recruit and activate caspase-8. We found that CD95 was preferentially located in lipid rafts of type I cells, while it was present both in raft and non-raft plasma membrane sub-domains of type II cells. After stimulation, CD95 located in phospholipid-rich plasma membrane was recruited to lipid rafts in both types of cells. Similarly, CD95 cross-linking resulted in caspase-independent translocation of FADD/MORT1 and caspase-8 to the lipid rafts, which was prevented by a death domain-defective receptor. CD95 internalization was then rapid in type I and delayed in type II cells and showed a substantial correlation with the kinetics of Fas-associated death domain (FADD)and caspase-8 recruitment to lipid rafts. Finally, electron microscopy analysis showed that after CD95 stimulation lipid rafts aggregated in large clusters that were internalized in endosomal vesicles, where caspase-8 underwent massive processing. Taken together, our data demonstrate that CD95 death-inducing signaling complex formation and internalization in type I and type II cells occur in lipid rafts, which are a major site of caspase-8 activation.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2004-07-01 | European Journal of Immunology |