Isolation of a Golgi-apparatus-enriched fraction from leukaemic cells.
1. A Golgi-apparatus-enriched fraction was isolated from acute leukaemic lymphoblasts of AKR mice by using an homogenate stabilized with 1 mM-glutaraldehyde. 2. The isolated fraction, which was shown morphologically to be enriched in dictyosomes, possessed between 44- and 76-fold increase in specific activity, compared with the tumour homogenate, of UDP-galactose-glycoprotein galactosyltransferase and between 3- and10.5-fold increase in relative specific activity of UDP-N-acetygalactosamine-polypeptide N-acetylgalactosaminyltransferase. 3. Plasma membranes isolated from the leukaemic lymphoblasts also possessed glycoprotein galactosyltransferase activity, though in contrast with Golgi-apparatus-enriched material had no detectable polypeptide N-acetygalactosaminyltransferase. 4. The difficulties associated with maintaining the morphological integrity of the Golgi apparatus in subcellular fractionation are discussed.
D000818:Animals; D002458:Cell Fractionation; D002462:Cell Membrane / Q000201:enzymology; D002499:Centrifugation, Density Gradient; D005646:Fucosyl Galactose alpha-N-Acetylgalactosaminyltransferase / Q000032:analysis; D005976:Glutaral; D006056:Golgi Apparatus / Q000032:analysis / Q000201:enzymology; D007942:Leukemia, Experimental / Q000032:analysis; D007945:Leukemia, Lymphoid / Q000032:analysis* / Q000201:enzymology; D051379:Mice; D008806:Mice, Inbred AKR; D008861:Microsomes / Q000201:enzymology; D009708:Nucleotidases / Q000032:analysis; D010455:Peptides; D013395:Sucrose; D006022:beta-N-Acetylglucosaminylglycopeptide beta-1,4-Galactosyltransferase / Q000032:analysis
D010455:Peptides; D013395:Sucrose; D006022:beta-N-Acetylglucosaminylglycopeptide beta-1,4-Galactosyltransferase; D005646:Fucosyl Galactose alpha-N-Acetylgalactosaminyltransferase; D009708:Nucleotidases; D005976:Glutaral