title: Differences between the protein moieties of active subunits and EDTA-treated subunits of rat liver ribosomes with specific references to a 5 S rRNA - protein complex.
abstract: When active 40 S subunits of rat liver ribosomes were treated with EDTA, the conversion of 40 S subunits to 30 S subunits occurred with partial release of 13 kinds of proteins out of 29 kinds of 40 S proteins. Buy contrast, 60 S subunits completely lost one protein (L3) by EDTA-treatment with concomitant release of the fraction sedimenting at about 7 S (7 S fraction). It was found that the 7 S fraction contained 5 S ribosomal RNA as well as L3 protein having a molecular weight of 38,000. Buoyant density in CsCl of the 7 S fraction was 1.60 g/cm3, suggesting that this fraction consisted of RNA and protein at an approximately equal ratio on a weight basis. These findings, taken together with the molecular weights of 5 S rRNA (40,000) and L3 protein, may indicate that the 5 S ribosomal RNA - protein complex from rat liver 60 S subunits consists of one molecule of 5S ribosomal RNA and one molecule of L3 protein.
mesh_terms: D000818:Animals; D004492:Edetic Acid / Q000494:pharmacology*; D004591:Electrophoresis, Polyacrylamide Gel; D008099:Liver / Q000032:analysis / Q000648:ultrastructure*; D051381:Rats; D012269:Ribosomal Proteins / Q000032:analysis*; D012270:Ribosomes / Q000032:analysis / Q000187:drug effects / Q000648:ultrastructure*
chemical_list: D012269:Ribosomal Proteins; D004492:Edetic Acid