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.
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.
Sanchez
Mayka
M
European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany.
Galy
Bruno
B
Dandekar
Thomas
T
Bengert
Peter
P
Vainshtein
Yevhen
Y
Stolte
Jens
J
Muckenthaler
Martina U
MU
Hentze
Matthias W
MW
D020413:3' Untranslated Regions; D001483:Base Sequence; D002453:Cell Cycle; D006367:HeLa Cells; D006801:Humans; D007501:Iron / Q000378:metabolism*; D035941:Iron Regulatory Protein 1 / Q000378:metabolism; D035942:Iron Regulatory Protein 2 / Q000378:metabolism; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods*; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism*; D017027:Protein Tyrosine Phosphatases; D012326:RNA Splicing; D012689:Sequence Homology, Nucleic Acid
D020413:3' Untranslated Regions; D007501:Iron; D010744:Phosphoric Monoester Hydrolases; C120902:CDC14A protein, human; D017027:Protein Tyrosine Phosphatases; D035941:Iron Regulatory Protein 1; D035942:Iron Regulatory Protein 2