Aconitase 1 (ACO1)

Aconitase 1 is a cytosolic protein which binds to iron-responsive elements (IREs). IREs are stem-loop structures found in the 5""" UTR of ferritin mRNA, and in the 3""" UTR of transferrin receptor mRNA. The iron-induced binding to the IRE results in repression of translation of ferritin mRNA, and inhibition of degradation of the otherwise rapidly degrading transferrin receptor mRNA. The cytoplasmic IREBP interacts with the IREs of these mRNAs. The iron status of the cell determines the ability of IREBP to bind to an IRE through reversible oxidation-reduction of sulfhydryl groups that are critical for the high-affinity RNA-protein interaction. Thus, IREBP plays a central role in cellular iron homeostasis by regulating ferritin mRNA translation and TFRC mRNA stability