DNA-benzoquinone adducts analyzed by nuclease P1 m ediated 32P-postlabeling method

With the super high sensitivity，high reproducibility and accumcy，nuclease P1 mediated 32P-postlabeling version has been successfully used to analyze the DNA-benzoquinone(DNA-BQ)adducts formed from m vitro cultured cells，reaction of benzoquinone ith calf thymus DNA and nucleoside monophosphates．It has been proven that the maior radioactive spot，contributing more than 70% of the total radioactivity of DNA-BQ adducts detected，is from deoxycytidine(dC)modified by benzoqumone while a minor one from deoxyguanosme(dGl．The method is capable of detecting 1 adduct in 109 to 1010 DNA bases．