The sidedness of the biosynthesis of phosphatidylethanolamine in rat brain endoplasmic reticulum has been studied. Microsomal vesicles, which are produced during homogenization from the endoplasmic reticulum, were labelled in vitro through Kennedy's pathway or by base-exchange, then reacted with trinitrobenzenesulfonic acid in "non penetrating" conditions. The labelled molecules appear to be localized only on the outer leaflet of the vesicles. When PE was labelled in vivo by intracerebral injection of [1-3H] ethanolamine, the isotope distributed between both leaflets. The role that divalent cations could play in maintaining lipid asymmetry is taken into consideration.
TOPOLOGY OF LlPID-SYNTHESIZING ENZYMES IN BRAIN MICROSOMES
BINAGLIA, Luciano;ARIENTI, Giuseppe;CORAZZI, Lanfranco;ROBERTI, Rita;ALUNNI BISTOCCHI, Giovanni;PORCELLATI, Giuseppe
1983
Abstract
The sidedness of the biosynthesis of phosphatidylethanolamine in rat brain endoplasmic reticulum has been studied. Microsomal vesicles, which are produced during homogenization from the endoplasmic reticulum, were labelled in vitro through Kennedy's pathway or by base-exchange, then reacted with trinitrobenzenesulfonic acid in "non penetrating" conditions. The labelled molecules appear to be localized only on the outer leaflet of the vesicles. When PE was labelled in vivo by intracerebral injection of [1-3H] ethanolamine, the isotope distributed between both leaflets. The role that divalent cations could play in maintaining lipid asymmetry is taken into consideration.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
