title: Synthesis of fluorescent lactosylceramide stereoisomers.
abstract: The intracellular distribution of synthetic glycosphingolipids (GSLs) bearing a fluorophore can be monitored in living cells by fluorescence microscopy. We reported previously that variation in the length of the long-chain base and in the structure of the carbohydrate-containing polar head group of (2S,3R) (or D-erythro-)-beta-lactosylceramide (LacCer) did not alter the mechanism of endocytic uptake from the plasma membrane of various mammalian cell types [Singh, R.D., Puri, V., Valiyaveettil, J.T., Marks, D.L., Bittman, R., Pagano, R.E., 2003. Selective caveolin-1-dependent endocytosis of glycosphingolipids. Mol. Biol. Cell 14, 3254-3265]. To extend our examination of the molecular features in LacCer that are responsible for its uptake by the caveolar-requiring endocytic pathway, we have synthesized the three unnatural stereoisomers [(2R,3R)-, (2S,3S)-, and (2R,3S)] of dipyrromethene difluoride (BODIPY)-LacCer. These analogues will be used to probe the role of stereochemistry in the long-chain base of LacCer in the mechanism of endocytic uptake.
authors.affiliation: Department of Chemistry and Biochemistry, Queens College of the City University of New York, Flushing, NY 11367-1597, USA.
authors.forename: Yidong
authors.initials: Y
authors.lastname: Liu
authors.forename: Robert
authors.initials: R
authors.lastname: Bittman
mesh_terms: D000818:Animals; D015703:Antigens, CD; D001896:Boron Compounds / Q000737:chemistry; D021941:Caveolae / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D004705:Endocytosis; D005456:Fluorescent Dyes / Q000138:chemical synthesis*; D006028:Glycosphingolipids / Q000737:chemistry; D007790:Lactosylceramides / Q000138:chemical synthesis*; D008856:Microscopy, Fluorescence; D008956:Models, Chemical; D011162:Porphobilinogen / Q000031:analogs & derivatives / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: C095489:4,4-difluoro-4-bora-3a,4a-diaza-s-indacene; D015703:Antigens, CD; D001896:Boron Compounds; D005456:Fluorescent Dyes; D006028:Glycosphingolipids; D007790:Lactosylceramides; C507544:dipyrromethene; C009744:CDw17 antigen; D011162:Porphobilinogen