Biogenesis of plasmalemmal glycoproteins. Intracellular site of synthesis of mouse liver plasmalemmal 5'-nucleotidase as determined by the sub-cellular location of messenger RNA coding for 5'-nucleotidase.
1. Free and membrane-bound mouse liver polyribosomes were separated by prolonged density-gradient centrifugation of the post-mitochondrial supernatant. RNA was extracted from free and membrane-bound polyribosomes and mRNA purified by oligo(dT)-cellulose column chromatography. 2. Antisera against purified mouse liver plasma membrane 5'-nucleotidase and moust albumin were prepared and characterized. 3. Microinjection of equivalent amounts of mRNA from free and membrane-bound liver polyribosomes into Xenopus laevis oocytes indicated by immuno precipitation and sodium dodecylsulphate gel electrophoresis a higher proportion of mRNA coding for 5'-nucleotidase and serum albumin in membrane-bound polyribosomes than free polyribosomes. 4. Although small, significant amounts of serum albumin and 5'-nucleotidase were also coded for by mRNA purified from free polyribosomes. The results suggest that in vivo, mRNA in mouse liver membrane-bound polyribosomes codes for the synthesis of 17 times more 5'-nucleotidase than does the mRNA in free polyribosomes.
D000818:Animals; D001001:Anura; D002458:Cell Fractionation; D002462:Cell Membrane / Q000201:enzymology* / Q000648:ultrastructure; D005260:Female; D006023:Glycoproteins / Q000096:biosynthesis; D005779:Immunodiffusion; D008099:Liver / Q000201:enzymology*; D008297:Male; D051379:Mice; D009708:Nucleotidases / Q000096:biosynthesis* / Q000276:immunology; D009865:Oocytes / Q000378:metabolism; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000032:analysis / Q000378:metabolism*; D012270:Ribosomes / Q000201:enzymology / Q000648:ultrastructure; D013347:Subcellular Fractions / Q000032:analysis; D014981:Xenopus
D006023:Glycoproteins; D012333:RNA, Messenger; D009708:Nucleotidases