Ure2 internal ribosome entry site (IRES)

In molecular biology, the Ure2 internal ribosome entry site (IRES) is an RNA element present in the 5' UTR of the mRNA of Ure2. It allows 5' cap- and eIF4E-independent translation of an N-terminally truncated form of Ure2. This truncated form lacks the prion-forming domain. It is a 104 nucleotide region, smaller than most viral IRES elements, which forms a stem-loop structure. EIF2A represses this IRES resulting in an inhibition of translation of the N-terminally truncated Ure2.