Iron regulation of transferrin receptor mRNA levels requires iron-responsive elements and a rapid turnover determinant in the 3' untranslated region of the mRNA

J. L. Casey, David Koeller, V. C. Ramin, R. D. Klausner, J. B. Harford

Research output: Contribution to journalArticle

243 Citations (Scopus)

Abstract

Post-transcriptional regulation of transferrin receptor mRNA levels by iron is mediated by a portion of the 3'untranslated region (UTR) of the mRNA. We have previously shown that a 678 nucleotide fragment of the 3'UTR contains the regulatory element(s). Within this region are five RNA structures which resemble the iron-responsive element (IRE) in the 5' untranslated region of the ferritin mRNA which is regulated translationally by iron. The IREs from the ferritin and transferrin receptor mRNAs compete in an in vitro assay for interaction with a cytoplasmic protein; the activity of this IRE-binding protein is dependent upon the iron status of the cells. Based on further deletion analysis reported here, the sequences required for iron regulation of the transferrin receptor have been limited to 250 nucleotides which we have produced synthetically and cloned. This sequence, which contains three IREs, is capable of producing iron-dependent regulation of transferrin receptor levels. Removal of the three IREs from the synthetic element results in loss of iron regulation. Moreover, deletion of a single cytosine residue from each of the three IREs in the synthetic regulatory element eliminates high-affinity binding to the IRE-binding protein in vitro and results in low levels of iron-independent transferrin receptor expression, consistent with production of a constitutively unstable mRNA. These data indicate that the ability of the mRNA to interact with the IRE-binding protein is required for regulation of transferrin receptor mRNA levels by iron. Certain other deletions within the regulatory region which do not affect the in vitro interaction between the transferrin receptor RNA and the IRE binding protein result in relatively high levels of iron-independent transferrin receptor expression, consistent with production of a constitutively stable mRNA. Collectively, our data support a model for transferrin receptor regulation in which the interaction between the IRE-binding protein and the transferrin receptor mRNA can protect the transcript from rapid degradation that is mediated by a rapid turnover determinant within the regulatory region.

Original languageEnglish (US)
Pages (from-to)3693-3699
Number of pages7
JournalEMBO Journal
Volume8
Issue number12
StatePublished - 1989
Externally publishedYes

Fingerprint

Transferrin Receptors
3' Untranslated Regions
Iron
Iron-Regulatory Proteins
Messenger RNA
Nucleic Acid Regulatory Sequences
Nucleotides
RNA
5' Untranslated Regions
Cytosine
Ferritins
Sequence Analysis
Assays
Degradation

Keywords

  • iron-responsive element
  • mRNA stability
  • transferrin receptor
  • untranslated region

ASJC Scopus subject areas

  • Genetics
  • Cell Biology

Cite this

Iron regulation of transferrin receptor mRNA levels requires iron-responsive elements and a rapid turnover determinant in the 3' untranslated region of the mRNA. / Casey, J. L.; Koeller, David; Ramin, V. C.; Klausner, R. D.; Harford, J. B.

In: EMBO Journal, Vol. 8, No. 12, 1989, p. 3693-3699.

Research output: Contribution to journalArticle

@article{c9797898d33d4e3fa1b860cff13f8daa,
title = "Iron regulation of transferrin receptor mRNA levels requires iron-responsive elements and a rapid turnover determinant in the 3' untranslated region of the mRNA",
abstract = "Post-transcriptional regulation of transferrin receptor mRNA levels by iron is mediated by a portion of the 3'untranslated region (UTR) of the mRNA. We have previously shown that a 678 nucleotide fragment of the 3'UTR contains the regulatory element(s). Within this region are five RNA structures which resemble the iron-responsive element (IRE) in the 5' untranslated region of the ferritin mRNA which is regulated translationally by iron. The IREs from the ferritin and transferrin receptor mRNAs compete in an in vitro assay for interaction with a cytoplasmic protein; the activity of this IRE-binding protein is dependent upon the iron status of the cells. Based on further deletion analysis reported here, the sequences required for iron regulation of the transferrin receptor have been limited to 250 nucleotides which we have produced synthetically and cloned. This sequence, which contains three IREs, is capable of producing iron-dependent regulation of transferrin receptor levels. Removal of the three IREs from the synthetic element results in loss of iron regulation. Moreover, deletion of a single cytosine residue from each of the three IREs in the synthetic regulatory element eliminates high-affinity binding to the IRE-binding protein in vitro and results in low levels of iron-independent transferrin receptor expression, consistent with production of a constitutively unstable mRNA. These data indicate that the ability of the mRNA to interact with the IRE-binding protein is required for regulation of transferrin receptor mRNA levels by iron. Certain other deletions within the regulatory region which do not affect the in vitro interaction between the transferrin receptor RNA and the IRE binding protein result in relatively high levels of iron-independent transferrin receptor expression, consistent with production of a constitutively stable mRNA. Collectively, our data support a model for transferrin receptor regulation in which the interaction between the IRE-binding protein and the transferrin receptor mRNA can protect the transcript from rapid degradation that is mediated by a rapid turnover determinant within the regulatory region.",
keywords = "iron-responsive element, mRNA stability, transferrin receptor, untranslated region",
author = "Casey, {J. L.} and David Koeller and Ramin, {V. C.} and Klausner, {R. D.} and Harford, {J. B.}",
year = "1989",
language = "English (US)",
volume = "8",
pages = "3693--3699",
journal = "EMBO Journal",
issn = "0261-4189",
publisher = "Nature Publishing Group",
number = "12",

}

TY - JOUR

T1 - Iron regulation of transferrin receptor mRNA levels requires iron-responsive elements and a rapid turnover determinant in the 3' untranslated region of the mRNA

AU - Casey, J. L.

AU - Koeller, David

AU - Ramin, V. C.

AU - Klausner, R. D.

AU - Harford, J. B.

PY - 1989

Y1 - 1989

N2 - Post-transcriptional regulation of transferrin receptor mRNA levels by iron is mediated by a portion of the 3'untranslated region (UTR) of the mRNA. We have previously shown that a 678 nucleotide fragment of the 3'UTR contains the regulatory element(s). Within this region are five RNA structures which resemble the iron-responsive element (IRE) in the 5' untranslated region of the ferritin mRNA which is regulated translationally by iron. The IREs from the ferritin and transferrin receptor mRNAs compete in an in vitro assay for interaction with a cytoplasmic protein; the activity of this IRE-binding protein is dependent upon the iron status of the cells. Based on further deletion analysis reported here, the sequences required for iron regulation of the transferrin receptor have been limited to 250 nucleotides which we have produced synthetically and cloned. This sequence, which contains three IREs, is capable of producing iron-dependent regulation of transferrin receptor levels. Removal of the three IREs from the synthetic element results in loss of iron regulation. Moreover, deletion of a single cytosine residue from each of the three IREs in the synthetic regulatory element eliminates high-affinity binding to the IRE-binding protein in vitro and results in low levels of iron-independent transferrin receptor expression, consistent with production of a constitutively unstable mRNA. These data indicate that the ability of the mRNA to interact with the IRE-binding protein is required for regulation of transferrin receptor mRNA levels by iron. Certain other deletions within the regulatory region which do not affect the in vitro interaction between the transferrin receptor RNA and the IRE binding protein result in relatively high levels of iron-independent transferrin receptor expression, consistent with production of a constitutively stable mRNA. Collectively, our data support a model for transferrin receptor regulation in which the interaction between the IRE-binding protein and the transferrin receptor mRNA can protect the transcript from rapid degradation that is mediated by a rapid turnover determinant within the regulatory region.

AB - Post-transcriptional regulation of transferrin receptor mRNA levels by iron is mediated by a portion of the 3'untranslated region (UTR) of the mRNA. We have previously shown that a 678 nucleotide fragment of the 3'UTR contains the regulatory element(s). Within this region are five RNA structures which resemble the iron-responsive element (IRE) in the 5' untranslated region of the ferritin mRNA which is regulated translationally by iron. The IREs from the ferritin and transferrin receptor mRNAs compete in an in vitro assay for interaction with a cytoplasmic protein; the activity of this IRE-binding protein is dependent upon the iron status of the cells. Based on further deletion analysis reported here, the sequences required for iron regulation of the transferrin receptor have been limited to 250 nucleotides which we have produced synthetically and cloned. This sequence, which contains three IREs, is capable of producing iron-dependent regulation of transferrin receptor levels. Removal of the three IREs from the synthetic element results in loss of iron regulation. Moreover, deletion of a single cytosine residue from each of the three IREs in the synthetic regulatory element eliminates high-affinity binding to the IRE-binding protein in vitro and results in low levels of iron-independent transferrin receptor expression, consistent with production of a constitutively unstable mRNA. These data indicate that the ability of the mRNA to interact with the IRE-binding protein is required for regulation of transferrin receptor mRNA levels by iron. Certain other deletions within the regulatory region which do not affect the in vitro interaction between the transferrin receptor RNA and the IRE binding protein result in relatively high levels of iron-independent transferrin receptor expression, consistent with production of a constitutively stable mRNA. Collectively, our data support a model for transferrin receptor regulation in which the interaction between the IRE-binding protein and the transferrin receptor mRNA can protect the transcript from rapid degradation that is mediated by a rapid turnover determinant within the regulatory region.

KW - iron-responsive element

KW - mRNA stability

KW - transferrin receptor

KW - untranslated region

UR - http://www.scopus.com/inward/record.url?scp=0024819020&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0024819020&partnerID=8YFLogxK

M3 - Article

C2 - 2583116

AN - SCOPUS:0024819020

VL - 8

SP - 3693

EP - 3699

JO - EMBO Journal

JF - EMBO Journal

SN - 0261-4189

IS - 12

ER -