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Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1989 Aug;86(15):5768–5772. doi: 10.1073/pnas.86.15.5768

The iron-responsive element binding protein: a method for the affinity purification of a regulatory RNA-binding protein.

T A Rouault 1, M W Hentze 1, D J Haile 1, J B Harford 1, R D Klausner 1
PMCID: PMC297711  PMID: 2474819

Abstract

A method of affinity purification of a regulatory protein that binds specific RNA sequences is described. RNAs containing the regulatory sequences are transcribed in vitro from oligonucleotide templates, biotinylated, and incubated with unfractionated cytosol. Specific RNA-protein complexes are bound in solution to avidin, and the resulting complex is bound to biotin-agarose beads. The cytosolic binding protein is released from the RNA in high salt, and a second round of purification yields an essentially homogeneous protein. Using this method, we have identified the protein in human liver that binds iron-responsive RNA regulatory sequences. Iron-responsive elements (IREs) are RNA stem-loops present in the mRNAs encoding ferritin and the transferrin receptor. IREs form the basis for the translational regulation of ferritin gene expression and the regulation of transferrin receptor mRNA degradation rates. The IRE binding protein purified by this technique migrates as a 90-kDa polypeptide on SDS/PAGE. The interaction of the purified protein with IRE-containing RNAs can be detected by gel-mobility shift assays or by covalent crosslinking induced by UV irradiation.

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Selected References

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  1. Aziz N., Munro H. N. Iron regulates ferritin mRNA translation through a segment of its 5' untranslated region. Proc Natl Acad Sci U S A. 1987 Dec;84(23):8478–8482. doi: 10.1073/pnas.84.23.8478. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Casey J. L., Hentze M. W., Koeller D. M., Caughman S. W., Rouault T. A., Klausner R. D., Harford J. B. Iron-responsive elements: regulatory RNA sequences that control mRNA levels and translation. Science. 1988 May 13;240(4854):924–928. doi: 10.1126/science.2452485. [DOI] [PubMed] [Google Scholar]
  3. Grabowski P. J., Sharp P. A. Affinity chromatography of splicing complexes: U2, U5, and U4 + U6 small nuclear ribonucleoprotein particles in the spliceosome. Science. 1986 Sep 19;233(4770):1294–1299. doi: 10.1126/science.3638792. [DOI] [PubMed] [Google Scholar]
  4. Hentze M. W., Caughman S. W., Casey J. L., Koeller D. M., Rouault T. A., Harford J. B., Klausner R. D. A model for the structure and functions of iron-responsive elements. Gene. 1988 Dec 10;72(1-2):201–208. doi: 10.1016/0378-1119(88)90145-x. [DOI] [PubMed] [Google Scholar]
  5. Hentze M. W., Caughman S. W., Rouault T. A., Barriocanal J. G., Dancis A., Harford J. B., Klausner R. D. Identification of the iron-responsive element for the translational regulation of human ferritin mRNA. Science. 1987 Dec 11;238(4833):1570–1573. doi: 10.1126/science.3685996. [DOI] [PubMed] [Google Scholar]
  6. Hentze M. W., Rouault T. A., Caughman S. W., Dancis A., Harford J. B., Klausner R. D. A cis-acting element is necessary and sufficient for translational regulation of human ferritin expression in response to iron. Proc Natl Acad Sci U S A. 1987 Oct;84(19):6730–6734. doi: 10.1073/pnas.84.19.6730. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Hentze M. W., Rouault T. A., Harford J. B., Klausner R. D. Oxidation-reduction and the molecular mechanism of a regulatory RNA-protein interaction. Science. 1989 Apr 21;244(4902):357–359. doi: 10.1126/science.2711187. [DOI] [PubMed] [Google Scholar]
  8. Kadonaga J. T., Tjian R. Affinity purification of sequence-specific DNA binding proteins. Proc Natl Acad Sci U S A. 1986 Aug;83(16):5889–5893. doi: 10.1073/pnas.83.16.5889. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Koeller D. M., Casey J. L., Hentze M. W., Gerhardt E. M., Chan L. N., Klausner R. D., Harford J. B. A cytosolic protein binds to structural elements within the iron regulatory region of the transferrin receptor mRNA. Proc Natl Acad Sci U S A. 1989 May;86(10):3574–3578. doi: 10.1073/pnas.86.10.3574. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
  11. Leibold E. A., Munro H. N. Cytoplasmic protein binds in vitro to a highly conserved sequence in the 5' untranslated region of ferritin heavy- and light-subunit mRNAs. Proc Natl Acad Sci U S A. 1988 Apr;85(7):2171–2175. doi: 10.1073/pnas.85.7.2171. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Milligan J. F., Groebe D. R., Witherell G. W., Uhlenbeck O. C. Oligoribonucleotide synthesis using T7 RNA polymerase and synthetic DNA templates. Nucleic Acids Res. 1987 Nov 11;15(21):8783–8798. doi: 10.1093/nar/15.21.8783. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Müllner E. W., Kühn L. C. A stem-loop in the 3' untranslated region mediates iron-dependent regulation of transferrin receptor mRNA stability in the cytoplasm. Cell. 1988 Jun 3;53(5):815–825. doi: 10.1016/0092-8674(88)90098-0. [DOI] [PubMed] [Google Scholar]
  14. Rouault T. A., Hentze M. W., Caughman S. W., Harford J. B., Klausner R. D. Binding of a cytosolic protein to the iron-responsive element of human ferritin messenger RNA. Science. 1988 Sep 2;241(4870):1207–1210. doi: 10.1126/science.3413484. [DOI] [PubMed] [Google Scholar]
  15. Ruby S. W., Abelson J. An early hierarchic role of U1 small nuclear ribonucleoprotein in spliceosome assembly. Science. 1988 Nov 18;242(4881):1028–1035. doi: 10.1126/science.2973660. [DOI] [PubMed] [Google Scholar]
  16. Singh H., LeBowitz J. H., Baldwin A. S., Jr, Sharp P. A. Molecular cloning of an enhancer binding protein: isolation by screening of an expression library with a recognition site DNA. Cell. 1988 Feb 12;52(3):415–423. doi: 10.1016/s0092-8674(88)80034-5. [DOI] [PubMed] [Google Scholar]
  17. Walden W. E., Daniels-McQueen S., Brown P. H., Gaffield L., Russell D. A., Bielser D., Bailey L. C., Thach R. E. Translational repression in eukaryotes: partial purification and characterization of a repressor of ferritin mRNA translation. Proc Natl Acad Sci U S A. 1988 Dec;85(24):9503–9507. doi: 10.1073/pnas.85.24.9503. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Zähringer J., Baliga B. S., Munro H. N. Novel mechanism for translational control in regulation of ferritin synthesis by iron. Proc Natl Acad Sci U S A. 1976 Mar;73(3):857–861. doi: 10.1073/pnas.73.3.857. [DOI] [PMC free article] [PubMed] [Google Scholar]

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