Ectopic Expression of a Poplar Gene PtrMYB119 Confers Enhanced Tolerance to Drought Stress in Transgenic Nicotiana tabacum

Drought stress is a major limiting factor during the process of plant growth and development, especially in arid and semi-arid regions. MYB transcription factors play vital roles in the regulation of many developmental processes under various stresses. The aim of this study was to determine whether <i>PtrMYB119</i> enhanced dehydration tolerance in <i>Nicotiana tabacum</i>. <i>PtrMYB119</i>, with a weak transactivation activity, was distributed throughout the cell with no apparent specificity. The transgenic tobacco overexpressing <i>PtrMYB119</i> might regulate dehydration tolerance through increased ABA content and antioxidant enzyme activities, decreased MDA levels, and up-regulation of antioxidant genes, polyamine biosynthesis genes, and drought-responsive genes. Overall, our results could contribute to the elucidation of drought tolerance underlying <i>PtrMYB119</i> action in tobacco and indicated that <i>PtrMYB119</i> could be exploited for engineering drought-enduring plants in the future.