Ceramide-enriched membrane domains.
Cellular activation involves the re-organization of receptor molecules and the intracellular signalosom in the cell membrane. Recent studies indicate that specialized domains of the cell membrane, termed rafts, are central for the spatial organization of receptors and signaling molecules. Rafts are converted into larger membrane platforms by activity of the acid sphingomyelinase, which hydrolyses raft-sphingomyelin to ceramide. Ceramide molecules spontaneously associate to form ceramide-enriched microdomains, which fuse to large ceramide-enriched membrane platforms. The acid sphingomyelinase is activated by multiple stimuli including CD95, CD40, DR5/TRAIL, CD20, FcgammaRII, CD5, LFA-1, CD28, TNF, the Interleukin-1 receptor, the PAF-receptor, CD14, infection with P. aeruginosa, S. aureus, N. gonorrhoeae, Sindbis-Virus, Rhinovirus, treatment with gamma-irradiation, UV-light, doxorubicin, cisplatin, disruption of integrin-signaling and under some conditions of developmental death. Ceramide-enriched membrane platforms serve the clustering of receptors, the recruitment of intracellular signaling molecules and the exclusion of inhibitory signaling factors and, thus, facilitate signal transduction initiated by the specific stimulus.
Bollinger
Claudia R
CR
Department of Molecular Biology, University of Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany.
Teichgräber
Volker
V
Gulbins
Erich
E
D000818:Animals; D018407:Bacterial Physiological Phenomena; D002518:Ceramides / Q000378:metabolism*; D004789:Enzyme Activation; D006801:Humans; D021962:Membrane Microdomains / Q000378:metabolism*; D008565:Membrane Proteins / Q000502:physiology; D015398:Signal Transduction; D013108:Sphingomyelin Phosphodiesterase / Q000378:metabolism; D013109:Sphingomyelins / Q000378:metabolism; D018406:Virus Physiological Phenomena
D002518:Ceramides; D008565:Membrane Proteins; D013109:Sphingomyelins; D013108:Sphingomyelin Phosphodiesterase