Fig. 1

Mechanism of translation modulation by the IRP-IRE signaling pathway. a The translation of transcripts containing an IRE in the 5′-UTR can occur in the absence of IRP binding to the IRE; (b) after the binding of IRP to the IRE in the 5′-UTR, translation of the transcripts is inhibited. c Iron can bind to IRP to induce a transformational change of IRP, leading to its dissociation from the IRE, which can promote the translation of transcripts. d The IRE can be present in the 3′-UTR of the transcript. Without IRP binding to the 3′-UTR, the transcript can be susceptible to endonuclease attack and degradation, leading to down-regulation of translation. e Binding of IRP to the IRE in the 3′-UTR can protect transcripts against endonuclease degradation and therefore promote the translation of transcripts. f Iron can bind to IRP, leading to the dissociation of IRP from the IRE in the 3′-UTR, endonuclease attack, and the degradation of transcripts, which down-regulates the translation of transcripts