Sigma® is proud to offer IPTG-inducible vectors as the latest development from our continued partnership in TRC.
The pLKO vector has been redesigned to contain a LacI (repressor) and a modified human U6 shRNA promoter with LacO (operator) sequences. In the absence of IPTG (isopropyl-Β-D-thio-galactoside), an analogue of lactose, LacI binds to LacO preventing expression of the shRNA. When IPTG is present, the allosteric LacI repressor changes conformation, releasing itself from lacO modified human U6 promoter, and subsequently allows expression of the shRNA.
The vector contains an shRNA insert that does not target any known genes, making it useful as a negative control in experiments using the MISSION inducible shRNA library clones. This allows one to examine the effect of transfection of a short-hairpin on gene expression and interpret the knockdown effect seen with shRNA clones. Ampicillin and puromycin antibiotic resistance genes provide selection in bacterial or mammalian cells respectively. In addition, self-inactivating replication incompetent viral particles can be produced in packaging cells (HEK293T) by co-transfection with compatible packaging plasmids. The 1X LacO Inducible Non-Target shRNA Control is provided as 10 μg of plasmid DNA in Tris-EDTA (TE) buffer at a concentration of 500 ng/μl.