title: Filipin recognizes both GM1 and cholesterol in GM1 gangliosidosis mouse brain.
abstract: Filipin is an antibiotic polyene widely used as a histochemical marker for cholesterol. We previously reported cholesterol/filipin-positive staining in brain of β-galactosidase (β-gal) knockout ((-/-)) mice (GM1 gangliosidosis). The content and distribution of cholesterol and gangliosides was analyzed in plasma membrane (PM) and microsomal (MS) fractions from whole-brain tissue of 15 week-old control (β-gal(+/-)) and GM1 gangliosidosis (β-gal(-/-)) mice. Total ganglioside content (μg sialic acid/mg protein) was 3-fold and 7-fold greater in the PM and MS fractions, respectively, in βgal(-/-) mice than in βgal(+/-) mice. GM1 content was 30-fold and 50-fold greater in the PM and MS fractions, respectively. In contrast, unesterified cholesterol content (μg/mg protein) was similar in the PM and the MS fractions of the βgal(-/-) and βgal(+/-) mice. Filipin is known to bind to various sterol derivatives and phospholipids on thin-layer chromatograms. Biochemical evidence is presented showing that filipin also binds to GM1 with an affinity similar to that for cholesterol, with a corresponding fluorescent reaction. Our data suggest that the GM1 storage seen in the β-gal(-/-) mouse contributes to the filipin ultraviolet fluorescence observed in GM1 gangliosidosis brain. The data indicate that in addition to cholesterol, filipin can also be useful for detecting GM1.
authors.affiliation: Department of Biology, Boston College, 140 Commonwealth Avenue, Chestnut Hill, MA 02467, USA.
authors.forename: Julian R
authors.initials: JR
authors.lastname: Arthur
authors.forename: Karie A
authors.initials: KA
authors.lastname: Heinecke
authors.forename: Thomas N
authors.initials: TN
authors.lastname: Seyfried
mesh_terms: D000818:Animals; D001692:Biological Transport; D001921:Brain / Q000378:metabolism* / Q000473:pathology; D002462:Cell Membrane / Q000378:metabolism; D002784:Cholesterol / Q000378:metabolism*; D005260:Female; D005372:Filipin / Q000378:metabolism*; D005677:G(M1) Ganglioside / Q000378:metabolism*; D005732:Gangliosides / Q000378:metabolism; D016537:Gangliosidosis, GM1 / Q000378:metabolism* / Q000473:pathology; D008297:Male; D051379:Mice; D008861:Microsomes / Q000378:metabolism; D013194:Staining and Labeling
chemical_list: C011258:G(A1) ganglioside; D005732:Gangliosides; D005677:G(M1) Ganglioside; D005372:Filipin; D002784:Cholesterol