The CRE of poliovirus is identified as an unachieved base-paired stem and a final loop consisting of 61 nt. The CRE is found in enteroviruses. Itis a highly preserved secondary   RNA structural element and bedded in the genome's polyprotein-coding region. The complex can be translocated to the 5  region of the genome that have no coding activity, at least 3.7-kb distant from the initial location. This process can occurs without negatively influencing activity. CRE copies don't influence replication negatively. Uridylylation process of VPg that takes place at CRE needs the presence of 3CDpro that is an RNA binding protein. It is attached to the CRE directly and specifically. Because of its presence VPg can bind the CRE properly and primary production proceeds without problems.