title: Localization of lipoxygenase activity on the oil bodies and in protoplasts using a novel fluorescence imaging method.
abstract: Lipoxygenase (linoleate:oxygen oxidoreductase; EC 1.13.11.12; LOX) catalyzes oxygenation of polyenoic fatty acids, which precedes the degradation of storage lipids during seed germination in sunflower. In the present work, it has been confirmed that 2',7'-dichlorodihydrofluorescein diacetate (H(2)DCFDA) produces fluorescence in presence of lipid hydroperoxides (LOX reaction products). This work provides new information on spatial localization of transiently enhanced LOX activity in protoplasts from 5 d old seedling cotyledons of sunflower (Helianthus annuus L. cv. Morden) by exploiting H(2)DCFDA as a probe for fluorescence detection from LOX activity sites. Use of LOX inhibitors [nordihydroguaiaretic acid (NDGA) and propyl gallate (PG)] confirms oil bodies as LOX activity sites. Oil body surface has been shown to possess LOX activity in 5 d old seedling cotyledons.
authors.affiliation: Laboratory of Plant Physiology, Department of Botany, University of Delhi, Delhi 110007, India.
authors.forename: Mukesh K
authors.initials: MK
authors.lastname: Yadav
authors.forename: Satish C
authors.initials: SC
authors.lastname: Bhatla
mesh_terms: D018548:Cotyledon / Q000187:drug effects / Q000201:enzymology; D005452:Fluoresceins / Q000378:metabolism; D006368:Helianthus / Q000187:drug effects / Q000201:enzymology*; D008054:Lipid Peroxides / Q000378:metabolism; D008084:Lipoxygenase / Q000378:metabolism*; D009637:Masoprocol / Q000494:pharmacology; D011435:Propyl Gallate / Q000494:pharmacology; D011523:Protoplasts / Q000187:drug effects / Q000201:enzymology*; D036226:Seedlings / Q000187:drug effects / Q000201:enzymology; D012639:Seeds / Q000187:drug effects / Q000201:enzymology
chemical_list: C110400:2',7'-dichlorodihydrofluorescein diacetate; D005452:Fluoresceins; D008054:Lipid Peroxides; D009637:Masoprocol; D011435:Propyl Gallate; D008084:Lipoxygenase