This vector uses the human H1 promoter to express a small hairpin RNA sequence that can silence gene expression. A short cDNA that includes a sequence from the target gene is ligated into the insertion site adjacent to the promoter.?The cDNA is constructed by annealing compementary oligonucleotides to one another.?Each oligonucleotide is designed with a 4-base overhang at its 5'-end.?The overhangs complement vector sequences that remain after digestion with a pair of restriction enzymes.?The other features of the plasmid facilitate its rapid conversion to an adenovirus vector using the SpeAd procedure.

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