Iron regulation and the cell cycle: identification of an iron-responsive element in the 3'-untranslated region of human cell division cycle 14A mRNA by a refined microarray-based screening strategy

J Biol Chem. 2006 Aug 11;281(32):22865-74. doi: 10.1074/jbc.M603876200. Epub 2006 Jun 7.

Abstract

Iron regulatory proteins (IRPs) 1 and 2 post-transcriptionally control mammalian iron homeostasis by binding to iron-responsive elements (IREs), conserved RNA stem-loop structures located in the 5'- or 3'-untranslated regions of genes involved in iron metabolism (e.g. FTH1, FTL, and TFRC). To identify novel IRE-containing mRNAs, we integrated biochemical, biocomputational, and microarray-based experimental approaches. IRP/IRE messenger ribonucleoproteins were immunoselected, and their mRNA composition was analyzed using an IronChip microarray enriched for genes predicted computationally to contain IRE-like motifs. Among different candidates, this report focuses on a novel IRE located in the 3'-untranslated region of the cell division cycle 14A mRNA. We show that this IRE motif efficiently binds both IRP1 and IRP2. Differential splicing of cell division cycle 14A produces IRE- and non-IRE-containing mRNA isoforms. Interestingly, only the expression of the IRE-containing mRNA isoforms is selectively increased by cellular iron deficiency. This work describes a new experimental strategy to explore the IRE/IRP regulatory network and uncovers a previously unrecognized regulatory link between iron metabolism and the cell cycle.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3' Untranslated Regions
  • Base Sequence
  • Cell Cycle*
  • HeLa Cells
  • Humans
  • Iron / metabolism*
  • Iron Regulatory Protein 1 / metabolism
  • Iron Regulatory Protein 2 / metabolism
  • Molecular Sequence Data
  • Nucleic Acid Conformation
  • Oligonucleotide Array Sequence Analysis / methods*
  • Phosphoric Monoester Hydrolases / metabolism*
  • Protein Tyrosine Phosphatases
  • RNA Splicing
  • Sequence Homology, Nucleic Acid

Substances

  • 3' Untranslated Regions
  • Iron
  • Phosphoric Monoester Hydrolases
  • CDC14A protein, human
  • Protein Tyrosine Phosphatases
  • Iron Regulatory Protein 1
  • Iron Regulatory Protein 2