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Roche Applied Science s X-tremeGene siRNA Transfection Reagent and Promega s GeneClip U1 Hairpin Cloning Systems


Roche Applied Science has recently introduced the X-tremeGene siRNA transfection reagent.

According to the company, the reagent requires no media changes and demonstrates minimal cytotoxicity. Additional details about the product can be found at

Promega has introduced a line of GeneClip U1 hairpin cloning systems.

The systems, the company said, consist of linearized plasmids designed for the cloning of human target sequences to express short-hairpin RNAs in human cells.

After transfection into human cells, in vivo expression of short-interfering RNAs can be effectively achieved from DNA constructs that contain a U1 RNA polymerase promoter and a siRNA template, Promega said. The U1 promoter has been used successfully to generate hairpin siRNAs in vivo.

“To insert hairpin siRNAs into the pGeneClip vectors, two short DNA oligonucleotides are annealed to form a DNA insert that contains the hairpin siRNA target sequence,” according to Promega. “After annealing, the oligonucleotides form overhangs that are compatible with the pGeneClip vector ends and facilitate sticky-end ligation. Once transfected, RNA polymerase II transcribes the hairpin insert sequences to generate hairpin siRNAs in vivo.”

The company has released a basic GeneClip U1 hairpin cloning system, as well as puromycin, hygromycin, neomycin, and hMGFP versions.

Details about the systems can be found at


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