Input chromatin estimation - (Oct/16/2005 )

Hi! I'm working with the nChip protocol. But now, I have a problem with the estimation of the input chromatin concentration. I need this data to put 40 microg of chromatin per immunoprecipitation. How can I know the concentration of DNA if the DNA is bound to the histone core, and affect the abs in the spectrophotometer. I think that a good option could be measure DNA with sybergreen, in the real time machine, with a dilution curve, without a pcr reaction. but I'm not sure. I have something quick, and simple. I coud use this method to know the DNA concentration before MNase treatmen, because I have some mRNAs that affects this measure. Thanks!!!!

you could estimate based upon the celera prediction of 6.6pg of genomic DNA/cell and assume 100% lysis etc...

Why has it got to be exactly 40 microg? If you are particularly worried about the quick but somewhat inaccurate method of specing bound DNA then why not do a quick P/C DNA extraction of an aliquot and then check it?