Biological Activity:

RS-1was previously characterized as a RAD51-Stimulatory compound and now found to be an HDR enhancer to enhance CRISPR/Cas9- and TALEN-mediated knock-in efficiency. It increases the knock-in efficiency by two- to five-fold at different loci, whereas NHEJ inhibitor SCR7 has minimal effects. RS-1 was applied for animal production and have achieved multifold improvement on the knock-in rates as well. RS-1 can stimulate the human homologous recombination protein RAD51in various conditions. In PC3 prostate cancer cells, RS-1–induced lethality was accompanied by the formation of microscopically visible RAD51 nuclear protein foci occurring in the absence of any DNA-damaging treatment. Treatment with RS-1 promoted significant antitumor responses in a mouse model.

How to Use:

In vitro: RS-1 was used at 15 µM final concentration in TALEN- or Cas9-mediated knock-in experiments.
In vivo: RS-1 was used at 7.5 μM for the in vivo knock-in animal production. RS-1 can be dosed to animal by IP injection at 110 mg/Kg once per day to get antitumor responses.

Reference:

• 1. Jayathilaka K, et al. A chemical compound that stimulates the human homologous recombination protein RAD51. (2008) Proc Natl Acad Sci USA. 105(41):15848-53.
• 2. Mason JM, et al. The RAD51-stimulatory compound RS-1 can exploit the RAD51 overexpression that exists in cancer cells and tumors. (2014) Cancer Res. 74(13):3546-55. 
• 3. Song J, et al. RS-1 enhances CRISPR/Cas9- and TALEN-mediated knock-in efficiency. (2016) Nat Commun. 7:10548.