title: The polysomal proteins of L cells. Discrimination between the structural ribosomal proteins, the exchangeable ribosomal proteins and the non-ribosomal proteins by two-dimensional dodecylsulfate electrophoresis and autoradiography.
abstract: Three groups of proteins can be clearly discriminated in the total protein of L cell polysomes by selective labelling in the presence of low doses of actinomycin D and two-dimensional polyacrylamide/dodecylsulfate gel electrophoresis followed by autoradiography: (a) structural ribosomal proteins which are not labelled in the presence of actinomycin D and form stained non-radioactive spot in gels; (b) exchangeable ribosomal proteins which are labelled in the presence of actinomycin D and stained radioactive spots; (c) non-ribosomal proteins which are detectable only by autoradiography of gels. The large and small subunits of L cell ribosomes contain respectively 45 and 34 ribosomal proteins with molecular weights less than or equal to 50 000; seven of the large subunit proteins and nine of the small subunit proteins are exchangeable. Most of the non-ribosomal proteins migrate in the region of the related to the separation of the ribosomal proteins of mammalian cells and the possible significance of the presence of non-ribosomal proteins in polysomes are discussed.
mesh_terms: D003609:Dactinomycin / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D007739:L Cells / Q000032:analysis* / Q000378:metabolism; D008970:Molecular Weight; D011132:Polyribosomes / Q000032:analysis* / Q000187:drug effects / Q000378:metabolism; D012269:Ribosomal Proteins / Q000096:biosynthesis / Q000302:isolation & purification; D012967:Sodium Dodecyl Sulfate
chemical_list: D012269:Ribosomal Proteins; D003609:Dactinomycin; D012967:Sodium Dodecyl Sulfate