Cytoplasmic Protein Binds in vitro to a Highly Conserved Sequence in the 5′ Untranslated Region of Ferritin Heavy- and Light-Subunit mRNAs

• Published in: Proceedings of the National Academy of Sciences - PNAS 1988-04, Vol.85 (7), p.2171-2175
• Main Authors: Leibold, Elizabeth A., Munro, Hamish N.
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Carrier Proteins - metabolism; Chemical bases; Conserved sequences; Ferritins; Ferritins - biosynthesis; Ferritins - genetics; Fundamental and applied biological sciences. Psychology; Gels; Gene expression; Gene Expression Regulation; Heparin; Hepatocellular carcinoma; Introns; Iron - pharmacology; Liver; Liver - analysis; Liver Neoplasms, Experimental; Male; Messenger RNA; Molecular and cellular biology; Molecular genetics; Myocardium - analysis; Rats; Rats, Inbred Strains; RNA; RNA Processing, Post-Transcriptional; RNA, Messenger - metabolism; RNA-Binding Proteins; Tumor Cells, Cultured - analysis; Untranslated regions
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.85.7.2171

The mRNAs for the heavy and light subunits of the iron-storage protein ferritin occur in cells largely as inactive ribonucleoprotein particles, which are recruited for translation when iron enters the cell. Cytoplasmic extracts from rat tissues and hepatoma cells were shown by an electrophoretic separation procedure to form RNA-protein complexes involving a highly conserved sequence in the 5′ untranslated region of both ferritin heavy- and light-subunit mRNAs. The pattern of complex formation was affected by pretreatment of rats or cells with iron. Crosslinking by UV irradiation showed that the complexes contained an 87-kDa protein interacting with the conserved sequence of the ferritin mRNA. We propose that intracellular iron levels regulate ferritin synthesis by causing changes in specific protein binding to the conserved sequence in the ferritin heavy- and light-subunit mRNAs.