Improved translation efficiency in chrysanthemum and torenia with a translational enhancer derived from the tobacco alcohol dehydrogenase gene

We investigated the efficiency of the 5'-untranslated region (UTR) of the tobacco alcohol dehydrogenase gene (NtADH-5'UTR) as a translational enhancer in chrysanthemum (Chrysanthemum morifolium) and torenia (Torenia fournieri). Three constructs were introduced: control, ADH-, cauliflower mosaic virus 35S RNA (CaMV 35S) promoter::beta-glucuronidase (GUS); NtADH-5'UTR with a spacer, ADH+S, CaMV 35S promoter::NtADH-5'UTR::25-bp spacer::GUS; and NtADH-5'UTR with no spacer, ADH+, CaMV 35S promoter:: NtADH-5'UTR::GUS. The highest GUS activity in ADH+S and ADH+ for chrysanthemum was about 45 and 190 times, respectively, and for torenia was 12 and 22 times, respectively, than that for the ADH-plants. NtADH-5'UTR enhanced translational efficiency in both species. With the lowest translational efficiency set to 1, the relative translational efficiencies were 1 to 15 (ADH-), 47 to 568 (ADH+S), and 267 to 1360 (ADH+) for chrysanthemum, and 1 to 3 (ADH-), 47 to 114 (ADH+S), and 85 to 226 (ADH+) for torenia. NtADH-5'UTR would facilitate practical breeding and fundamental genetic research in chrysanthemum and torenia.