title: Evidence for the protection of specific RNA sequences in globin messenger ribonucleoprotein particles.
abstract: Purified 15 S globin mRNA-protein (mRNP) complexes obtained by EDTA dissociation of duck reticulocytes polyribosomes were digested with the calcium dependant Staphylococcus aureus nuclease (EC 3. 1. 4. 7.). 25% of the globin mRNA sequences were resistant to extensive nuclease digestion as determined by TCA precipitation of the digested 15 S particles labelled in vivo with tritiated uridine. Polyacrylamide gel electrophoresis of the RNA from nuclease digested 15 S particles showed that the protected oligoribonucleotides were distributed into two distinct size classes of 25,000 and 12,000 MW. Comparison between in vitro iodine-labelled 9 S globin mRNA extracted from Staphylococcal nuclease digested 15 S mRNP particles was carried out by fingerprinting. Mapping of T1 ribonuclease digests by high-voltage electrophoresis and homochromatography showed that specific oligoribonucleotides were protected against nuclease attack by proteins of the 15 S mRNP.
mesh_terms: D000818:Animals; D001483:Base Sequence; D004372:Ducks; D005914:Globins / Q000096:biosynthesis*; D009698:Nucleoproteins; D009843:Oligoribonucleotides / Q000032:analysis; D011132:Polyribosomes / Q000378:metabolism; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000378:metabolism; D012156:Reticulocytes / Q000378:metabolism; D006163:Ribonuclease T1; D012261:Ribonucleoproteins
chemical_list: D009698:Nucleoproteins; D009843:Oligoribonucleotides; D012333:RNA, Messenger; D012261:Ribonucleoproteins; D005914:Globins; D006163:Ribonuclease T1