University of Arkansas, Fayetteville Division of Agriculture


Gene silencing is a process of suppressing activity of specific genes by producing “interfering” RNA encoded by foreign genes. This process serves as the principle of genetic modification in plants and animals, which is an important tool in genomics and biotechnology, allowing scientists to manipulate organisms to better meet human demands. New approaches of gene silencing may enable improvements on current practices of genetic modification, and broaden the application and impact of gene silencing in biotechnology. Recently, a novel vector design consisting of the transcription of short gene fragments lacking transcription termination signals was demonstrated to be effective in partial silencing of two separate genes in the model plant, Arabidopsis thaliana. To test the efficacy of this unterminated transgene technique on a broader range of genes in A. thaliana, a DNA vector to clone gene fragments was required. The objective of the present study was to design a silencing vector for rapid cloning of gene fragments and test its utility on new genes. Here, we report the successful construction of a simple transgene vector, pSJN15A, for cloning gene fragments, then plant transformation upon Agrobacterium infection. The pSJN15A vector was designed for direct cloning of gene fragments obtained by polymerase chain reaction. Transcription of gene fragments is directed by read-through activity of a hygromycin resistance gene promoter. The pSJN15A vector was used to develop silencing vectors against four new Arabidopsis genes. Thus, pSJN15A serves as an important DNA resource for testing the efficacy of silencing mediated by the transcription of gene fragments in various dicotyledonous plant species.