Lech, 

Nobody has reported anything on effectiveness of SCR7 in ES cells. Published works on other types of cells report a wide range of concentrations 0.01 to 1 uM (see Nat Biotech). I have used much higher concentration on hES cells and they seem pretty insensitive to it. 

Dear Kaveh,

Thanks for your reply. I'm considering titrating it by measuring HPRT-->Neo replacement efficiency. Would be nice to have some starting number though. Good to know you need more for hESCs.

Dear Lech and Kaveh, 

I was wondering what is the concentration of Scr7 that you have used in hES cells and for how long have you treated with the inhibitor? Thank you very much for your help!!

Nathaly

 Nathaly, 

I have tried a wide range of 0.1 uM to 20 uM. I have tried adding the SCR7 at different time points (anywhere between 8 to 24 hours after transfection of my targeting constructs). 

Dear Kaveh, Thanks a lot for your answer! Have you observed any of these doses to work better or do all they work the same (in terms of improving the obtention of clones with homologous recombination happening in both alleles)?

Dear Lech and Kaveh, have you succeed in using SCR7 to improve HDR efficiency in mouse ES cells? If so can you share your optimized conditions? Thanks!

Dear Weisheng,

We got satisfactory results without using SCR7, so we did not use it.

Cheers,

Lech

Dear all,

Did you try this in any other mammalian cells, say HeLa or U2OS? Any suggestions?