title: A nuclear specific glycoprotein representative of a unique pattern of glycosylation.
abstract: Whole rat liver nuclei were reacted with UDP-[14C]galactose in the presence of bovine beta(1----4) galactosyltransferase. The reaction mixture was electrophoresed on a reducing sodium dodecyl sulfate-polyacrylamide gel. Autoradiograms of the gel demonstrated a major labeled broad band migrating with an apparent molecular weight of 65,000-66,000. A number of other less prominently labeled bands were also present. The labeled 65,000-66,000 band when cut from the gel and subjected to alkaline reduction while in the gel matrix exclusively yielded a 14C-labeled disaccharide that co-migrated with a [14C]Gal-GlcNAcol standard in descending paper chromatography. Treatment of this disaccharide with beta-galactosidase (beta-D-galactoside galactohydrolase; EC 3.2.1.23) from Aspergillus niger removed all the [14C]galactose label. Treatment of the labeled 65,000-66,000 polypeptide with Endoglycosidase F, however, did not remove the [14C]galactose label. Western transfer blots of sodium dodecyl sulfate-polyacrylamide gel electrophoresis gels performed with horseradish peroxidase-labeled succinyl wheat germ agglutinin, a lectin specific for GlcNAc, on unlabeled nuclei revealed a dominant band at 63,000-64,000. Subjecting 14C-labeled nuclei to this procedure resulted in a shift of the major horseradish peroxidase-labeled succinyl wheat germ agglutinin band to 65,000-66,000. The shifted band was coincident with the [14C]galactose band as visualized on an autoradiogram. A survey of other rat tissue nuclei revealed the same spectrum of [14C]galactose acceptor proteins with a dominant 65,000-66,000 galactose-labeled band.
mesh_terms: D000818:Animals; D002250:Carbon Radioisotopes; D002467:Cell Nucleus / Q000378:metabolism*; D002845:Chromatography; D003101:Collodion; D004591:Electrophoresis, Polyacrylamide Gel; D005690:Galactose / Q000378:metabolism; D005700:Galactosyltransferases / Q000378:metabolism; D006023:Glycoproteins / Q000378:metabolism*; D006031:Glycosylation; D008099:Liver / Q000648:ultrastructure*; D008970:Molecular Weight; D011402:Pronase / Q000378:metabolism; D051381:Rats; D013379:Substrate Specificity; D014531:Uridine Diphosphate Galactose / Q000378:metabolism
chemical_list: D002250:Carbon Radioisotopes; D006023:Glycoproteins; D014531:Uridine Diphosphate Galactose; D003101:Collodion; D005700:Galactosyltransferases; D011402:Pronase; D005690:Galactose