Functional analyses of RNA structures shared between the internal ribosome entry sites of hepatitis C virus and the picornavirus porcine teschovirus 1 Talfan.
The internal ribosome entry site (IRES) of porcine teschovirus 1 (PTV-1), a member of the Picornaviridae family, is quite distinct from other well-characterized picornavirus IRES elements, but it displays functional similarities to the IRES from hepatitis C virus (HCV), a member of the Flaviviridae family. In particular, a dominant negative mutant form of eIF4A does not inhibit the activity of the PTV-1 IRES. Furthermore, there is a high level (ca. 50%) of identity between the PTV-1 and HCV IRES sequences. A secondary-structure model of the whole PTV-1 IRES has been derived which includes a pseudoknot. Validation of specific features within the model has been achieved by mutagenesis and functional assays. The differences and similarities between the PTV-1 and HCV IRES elements should assist in defining the critical features of this type of IRES.
Chard
Louisa S
LS
BBSRC Institute for Animal Health, Pirbright, Woking, Surrey GU24 0NF, United Kingdom.
Kaku
Yoshihiro
Y
Jones
Barbara
B
Nayak
Arabinda
A
Belsham
Graham J
GJ
D000818:Animals; D001483:Base Sequence; D004771:Enteroviruses, Porcine / Q000235:genetics*; D016174:Hepacivirus / Q000235:genetics*; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009690:Nucleic Acid Conformation; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics; D012367:RNA, Viral / Q000737:chemistry* / Q000235:genetics*; D012689:Sequence Homology, Nucleic Acid; D013045:Species Specificity; D013552:Swine
D012333:RNA, Messenger; D012367:RNA, Viral