The translation-enhancing region of the Semliki Forest virus subgenome is only functional in the virus-infected cell

We have recently shown that the Semliki Forest virus (SFV) subgenome contains a translation enhancer region in the coding part of its RNA. The enhancer increases the translation of the viral structural genes approximately ten-fold and thereby plays a key role in virus assembly. In this study we conclusively show that this translation enhancer represents an adaptation to the