Cas9 Lentiviruses (Inducible Tet-On) are replication incompetent, HIV-based, VSV-G pseudotyped lentiviral particles that are ready to transduce most mammalian cells, including primary and non-dividing cells. These viruses transduce cells with the Streptococcus pyogenes Cas9 gene under a tight TRE tetracycline-inducible promoter. Cas9 expression in the transduced cells is induced with doxycycline treatment, allowing temporal control of its expression, and when combined with sgRNA targeting gene(s) of interest allows gene editing events to be temporally controlled. The lentivirus vector also contains a geneticin selection gene (Figure 1).
Figure 1. Schematic of the lenti-vector used to generate the Cas9 lentivirus (Inducible Tet-On).
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Product Data Gallery
Cas9 protein expression in Cas9-Expressing iPS Cell Pool assessment by Western blot.
Two vials (500 µl x 2) of lentivirus at a titer 1 x 107 TU/ml. The titer will vary with each lot; the exact value is provided with each shipment.
Formulation
The lentiviruses were produced from HEK293T cells in medium containing 90% DMEM + 10% FBS. Virus particles can be packaged in custom formulations by special request, for an additional fee.
Background
Cas9 (Streptococcus pyogenes CRISPR associated protein 9) is an endonuclease that, when recruited to a specific DNA sequence by the appropriate sgRNA (single guide RNA), introduces a double stranded break into the DNA. This double stranded break can then be repaired through either Non-Homologous End Joining (NHEJ) or Homologous Recombination (HR). While NHEJ is an error prone process and causes insertions or deletions which may result in functional inactivation of the target gene, HR, in conjunction with a single stranded ssDNA repair construct, can be used to introduce mutations at specific base pair(s). Gene modifications introduced via Cas9 are now used in multiple fields of research aimed at understanding cellular mechanisms and developing therapeutic solutions.
Storage/Stability
Lentiviruses are shipped with dry ice. For long-term storage, it is recommended to store the lentiviruses at -80°C for up to 12 months from date of receipt. Avoid repeated freeze/thaw cycles. Titers can drop significantly with each freeze/thaw cycle.
Applications
Generation of Tet-inducible Cas9 stable cell lines (Geneticin (G418) selection) for genetic engineering studies.
Shipping Temperature
-80°C
Notes
The CRISPR/CAS9 technology is covered under numerous patents, including U.S. Patent Nos. 8,697,359 and 8,771,945, as well as corresponding foreign patents applications, and patent rights.
Biosafety The lentiviruses are produced with a SIN (self-inactivation) lentivector which ensures self-inactivation of the lentiviral construct after transduction and after integration into the genomic DNA of the target cells. None of the HIV genes (gag, pol, rev) will be expressed in the transduced cells, as they are expressed from packaging plasmids lacking the packing signal and are not present in the lentivirus particle. Although the pseudotyped lentiviruses are replication-incompetent, they require the use of a Biosafety Level 2 facility. BPS Bioscience recommends following all local federal, state, and institutional regulations and using all appropriate safety precautions.
Troubleshooting Guide For all questions, please email [email protected]