Subcellular distribution of glycosylphosphatidylinositol-specific phospholipase D in rat liver.
Glycosylphosphatidylinositol (GPI)-hydrolysing enzymes have been described in many mammalian tissues and body fluids; however, their site(s) of action and in vivo functions have remained unclear. In order to identify a possible intracellular site of GPI hydrolysis, we studied the subcellular distribution of GPI-hydrolysing activity in rat liver. We found that purified fractions from rat liver hydrolysed the GPI moieties of two GPI-anchored proteins with the specificity of a phospholipase D. This GPI-specific phospholipase D (GPI-PLD) activity was found to be highly enriched in a lysosomal fraction and showed a similar intracellular distribution to that of typical lysosomal enzymes. Our results indicate that lysosomes may represent a possible intracellular site of GPI-PLD action.
Hari
T
T
Institute of Biochemistry and Molecular Biology, University of Bern, Switzerland.
Kunze
H
H
Bohn
E
E
Brodbeck
U
U
Bütikofer
P
P
D000818:Animals; D006868:Hydrolysis; D008099:Liver / Q000201:enzymology*; D008297:Male; D010739:Phospholipase D / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D013347:Subcellular Fractions / Q000201:enzymology*
D010739:Phospholipase D; C065017:glycoprotein phospholipase D