Abstract
A terminator region works in transcription (RNA polymerase dissociation from DNA, RNA cleavage, and polyadenylation). Therefore, the use of an unsuitable terminator for transgene expression has the possibility of causing a decrease in the level of expression of the gene located in the downstream with oneself.
Usually nopaline synthase gene terminator (Tnos) is used as transgene terminator. Here we report that the use of Tnos causes decreasing downstream gene expression in transiently transformed Arabidopsis thaliana cultured cells and in stably transformed Nicotiana tabacum cultured cells. And the polyadenylation sites in Tnos have been greatly distributed in both cultured cells. These results suggested that Tnos is not suitable terminator region for transgene expression in plant cells.
In addition, we replaced the Tnos with A. thaliana endogeneous gene terminator. The use of endogeneous gene terminator shows an increase the transgene expression and a suppression of decreasing the downstream gene expression.
