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Secondary structure of the poliovirus type 1 (Mahoney) 5' non-translated region (NTR)

This genomic region has been divided into six domains (I to VI), of which domain I constitutes the cloverleaf and the remaining domains comprise the internal ribosome entry site (IRES). Spacer sequences without complex secondary structure exist between the cloverleaf and the IRES (nt 89-123) and between the IRES and the initiation codon (nt 620-742). Mutations in the 5'NTR of the Sabin poliovirus type 1, 2, and 3 vaccine strains localizing to nucleotides 480 (A to G), 481 (A to G), and 472 (C to U), respectively (each denoted by a star), confer attenuation in the CNS and deficient replication in neuroblastoma cells as well as reduced viral RNA translation efficiency. (Source: De Jesus NH. Epidemics to eradication: the modern history of poliomyelitis. Virol J 2007;4:70. Creative Commons Attribution [CC BY] license,

Associated Disorders

  • Aseptic meningitis
  • Bulbar polio
  • Bulbospinal polio
  • Infantile paralysis
  • Nonparalytic polio
  • Paralytic polio
  • Polioencephalitis
  • Post-polio progressive muscular atrophy
  • Post-polio syndrome
  • Spinal paralytic polio