부산대학교 도서관

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.febslet.2005.05.003 Byline: Ina Hummel, Karin Klappe, Jan Willem Kok Keywords: HepG2; Sphingolipids; Gangliosides; Lactosylceramide synthase; P-glycoprotein Abbreviations: ABC, ATP-binding cassette; Cer, ceramide; CSA, cyclosporin A; GlcCer, glucosylceramide; HPTLC, high performance thin layer chromatography; LacCer, lactosylceramide; Pgp, P-glycoprotein; SM, sphingomyelin Abstract: HepG2 cells, stably transfected with MDR1 cDNA, encoding the P-glycoprotein multidrug resistance efflux pump, display an altered sphingolipid composition compared to control cells, stably transfected with empty vector. The MDR1 overexpressing cells display a [approximately equal to]3-fold increased level of lactosylceramide and an increased ganglioside mass. Both the mRNA and the activity of lactosylceramide synthase were increased in HepG2/MDR1 cells. In conclusion, the increased glycolipid content in MDR1-transfected HepG2 cells is caused by a transcriptional up-regulation of the enzyme lactosylceramide synthase. Author Affiliation: University Medical Center Groningen, Department of Cell Biology, Section Membrane Cell Biology, A. Deusinglaan 1, Bldg 3215, 10th fl, 9713 AV Groningen, The Netherlands Article History: Received 22 April 2005; Revised 27 April 2005; Accepted 2 May 2005