Changes in the wheat Em 5′ UTR affect reporter gene expression in vivo and in vitro

The wheat Em gene is abundantly expressed in seed embryos during late embryogenesis and both transcriptional and post-transcriptional levels of control have been implicated. In this study, we have demonstrated that the wheat Em 5′ untranslated region (UTR) is capable of enhancing expression levels both in vivo and in vitro when present as part of a chimeric synthetic mRNA. Due to enhancement in both systems, we attribute the bulk of the increase in expression to enhanced translation. Computer-aided analysis of the Em 5′ UTR suggests that this sequence has the potential to form several stable secondary structures. When one of these structures, a predicted stem-loop, is deleted, expression is reduced in both the in vivo and in vitro assays suggesting that this region of the Em 5′ UTR may be involved in enhanced expression.