|MadSci Network: Cell Biology|
Unfortunately, if there is no previous data on the concentration limit, you have to perform serial dilutions and check cell viability. I assume you are using Geldanamycin, or a derivative (17-AAG17-DMAG) Geldanamycin causes a dose-dependent G2 arrest and reversible inhibition of entry into the S phase in studied cancer cells at 0.1 rwM, which is a pretty high concentration. Since the arrest is reversable, I'd suggest initial 10 fold dilutions (starting with 10mM and getting weaker), and see when the cells don't arrest. I know this is a pretty high amount to start with, but HSP90 is relatively abundent in the cell. Sorry I don't have more information, but it's pretty much trial and error if it hasn't been done before. I also found a link that might help. http://dtp.nci.nih.gov/branches/btb/ivclsp.html
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