Iron regulatory protein 2 (IPR029755)
Short name: IRE-BP2
Overlapping homologous superfamilies
- Aconitase/Iron-responsive element-binding protein 2 (IPR006249)
- Iron regulatory protein 2 (IPR029755)
In mammals, iron regulatory proteins (IRPs) 1 and 2 posttranscriptionally regulate expression of genes involved in iron metabolism by binding mRNA motifs called iron responsive elements (IREs) [PMID: 20603012]. IRP1 is a bifunctional protein that also has aconitase activity. IRP1 mostly exists in a non-IRE-binding, [4Fe-4S] cluster aconitase form which predominates when iron levels are normal; but if levels drop sufficiently the disassembly of the [4Fe-4S]-cluster occurs and there is a change of conformation to the IRE-binding form. On the other hand, IRP2 does not assemble an Fe-S cluster, lacks aconitase activity, and spontaneously binds IREs [PMID: 21566147]. Since IRP1 is predominantly in the enzymatic cytoplasmic aconitase form, it is IRP2 that acts as the major metabolic regulator that maintains iron homeostasis [PMID: 16850017]. IRP2 is also regulated. An iron-regulated E3 ubiquitin ligase complex targets IRP2 for proteasomal degradation [PMID: 19762597, PMID: 19762596].
This entry represents iron regulatory protein 2, also known as iron-responsive element-binding protein 2 (IRE-BP2).
- PTHR11670:SF31 (PTHR11670:SF31)