Iron-responsive element-binding protein 2 (IREB2)

Iron-responsive element-binding protein 2 (IREB2, also called IRP2) is an RNA-binding regulatory protein that controls cellular iron homeostasis. It binds to iron-responsive elements (IREs), stem-loop structures in the untranslated regions of target mRNAs, such as those coding for ferritin, transferrin receptor, and iron-metabolism-related proteins. By binding to IREs in either the 5' or 3' UTR, IREB2 represses translation (e.g., of ferritin) or stabilizes mRNA (e.g., transferrin receptor), balancing iron uptake, export, and storage in response to cellular iron status. IRP2 is distinct from its paralog IRP1/ACO1 in lacking aconitase activity and is regulated via proteasomal degradation in iron-replete conditions, with the strongest expression in the intestine and brain. Variants and overexpression of IREB2 have been implicated in cancer (especially prostate and lung), some neurodegenerative conditions, and COPD

Other names

IRP2IRBP2IRE-BP2IFR2iron-responsive element binding protein 2

Drugs altering iron metabolism may indirectly modulate IREB2 activity, but no selective therapeutics directly target IREB2