Novel cap-independent translation with the 5′-noncoding region of L-A virus mRNA

A novel cap-independent translation has been performed where the ribosome entry is regulated by the 5′-noncoding region (NCR) of L-A virus mRNA. Despite L-A virus mRNA containing neither cap structure nor a poly(A) tail, the reconstructed mRNA encoding the 5′ NCR of L-A virus mRNA and a reporter gene (luciferase) was translated, in yeast lysate, 60 times more efficiently than control mRNA. The 5′ NCR from L-A virus was effective in regulating the recruitment of ribosome in vitro. A possible mechanism in Saccharomyces cerevisiae is also suggested, whereby the ribosome entry is regulated by the 5′ NCR of L-A virus mRNA.