title: Novel nuclear methylation of sterols by the nematode Caenorhabditis elegans.
abstract: Caenorhabditis elegans possesses a unique sterol methylation pathway not reported to occur in any other organism and also removes the C-24 ethyl group of sitosterol (a plant sterol). This nematode produced substantial quantities of 4 alpha-methyl-5 alpha-cholest-8(14)-en-3 beta-ol and smaller amounts of lophenol from dietary cholesterol, desmosterol or sitosterol. When C. elegans was propagated in media containing sitosterol plus 25-azacoprostane hydrochloride (25-aza-5 beta-cholestane hydrochloride), an inhibitor of delta 24-sterol reductase in insects, its 4 alpha-methylsterol fraction largely consisted of equal amounts of 4 alpha-methyl-5 alpha-cholesta-7,24-dien-3 beta-ol and 4 alpha-methyl-5 alpha-cholesta-8(14),24-dien-3 beta-ol. Thus 25-azacoprostane hydrochloride inhibited both a delta 24-sterol reductase and a delta 7-sterol isomerase in C. elegans.
mesh_terms: D000818:Animals; D002107:Caenorhabditis / Q000378:metabolism*; D002784:Cholesterol / Q000378:metabolism; D003897:Desmosterol / Q000378:metabolism; D008401:Gas Chromatography-Mass Spectrometry; D009682:Magnetic Resonance Spectroscopy; D008745:Methylation; D012855:Sitosterols / Q000378:metabolism; D013261:Sterols / Q000378:metabolism*
chemical_list: D012855:Sitosterols; D013261:Sterols; D003897:Desmosterol; D002784:Cholesterol