The 5′ UTR has the ability to form a hairpin loop secondary structure (known as the IRE, Iron response element) that is recognized by iron-regulatory proteins (IRP1 and IRP2).
A 5′ UTR ten a capacidade de formar unha estrutura secundaria en bucle en forquita (chamada elemento de resposta ao ferro ou IRE, Iron response element) que é recoñecida polas proteínas reguladoras do ferro (IRP1 e IRP2).