Cytosolic cholesterol ester hydrolase from bovine corpus luteum. Its purification, identification, and relationship to hormone-sensitive lipase.
The cytosolic cholesterol ester hydrolase from bovine corpus luteum has been purified 760-fold, using isoelectric precipitation and gel filtration chromatography, followed by ion-exchange and adsorption chromatographies in the presence of non-ionic detergent. Further purification was achieved by affinity chromatography on triacylglycerol-containing polyacrylamide-agarose. The partially purified enzyme was inhibited by NaF, HgCl2 and DFP. Incubation with [3H]DFP resulted in specific labelling of a polypeptide of Mr = 84000, the same subunit molecular weight as that of the enzyme from adrenal cortex. This Mr 84000 polypeptide from corpus luteum was phosphorylated by the catalytic subunit of cyclic AMP-dependent protein kinase, phosphorylation causing greater than 2-fold activation of the enzyme. Several properties of the cholesterol ester hydrolase from corpus luteum show striking similarities to those of hormone-sensitive lipase from adipose tissue. This provides further evidence that hormone-sensitive lipase, in addition to its role in adipose tissue lipolysis, has a key role in steroidogenic tissues, namely catalysing the supply of free cholesterol from the cholesterol ester stores.
D000818:Animals; D002265:Carboxylic Ester Hydrolases / Q000302:isolation & purification*; D002384:Catalysis; D002417:Cattle; D002850:Chromatography, Gel; D003338:Corpus Luteum / Q000201:enzymology*; D003600:Cytosol / Q000201:enzymology; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation; D005260:Female; D008049:Lipase / Q000502:physiology*; D010455:Peptides / Q000302:isolation & purification*; D010766:Phosphorylation; D002787:Sterol Esterase / Q000302:isolation & purification* / Q000378:metabolism
D010455:Peptides; D002265:Carboxylic Ester Hydrolases; D002787:Sterol Esterase; D008049:Lipase