A PCR based method to construct small interference RNA expression vectors.

Small interference RNAs (siRNA) have been shown to be useful in the field of gene therapy and gene function studies. As a siRNA expression vector, pSilencer employ RNA polymerase III promoters and could stably produce siRNA for weeks. But once one siRNA sequence was inserted into the pSilencer vector, the other siRNA sequence will hardly be reconstructed, because the site of siRNA production has been occupied and difficult to be changed, so it is not suitable for screen of effective siRNA sequence. To solve this problem, we constructed the subclone pSilcencer329, which generated from pSilencer3.1, then developed a PCR based method of constructing siRNA expression vectors, and generated pSilencerBCL2L2 recombinants efficiently. This method was proven to be effective, reliable, and less expensive, and thus will be of great help in regular gene silencing studies, and will be especially suitable for large scale gene function analysis.