Virus entry into the target cells first requires interaction with DAF, which facilitates viral attachment to CAR, leading to internalization of the virus in the cytoplasm. After uncoating, the positive-sense single-stranded RNA genome is translated to yield a large single polyprotein. This process requires binding of ribosomes to IRES. The polyprotein is then proteolytically cleaved to generate structural (P1 cluster: VP1 to VP4) and NS (P2 cluster: 2Apro, 2B and 2C; P3 cluster: 3A, 3B, 3Cpro and 3Dpol) proteins by 2Apro and 3Cpro, two viral proteases. While the structural proteins, also called capsid proteins, contribute to the conformation of the virus, NS proteins mediate a variety of functions as indicated in the inset. During viral replication, 3Dpol plays a critical role in the formation of negative and positive strands of viral genomes, which can be paired to form dsRNA as an intermediate stage. The progeny virus containing a single-strand positive-sense RNA genome and structural proteins is finally released through cell lysis.