Energy transfer: A general method for the study of protein-nucleic acid interactions

A novel fluorescence method has been developed which should have general applicability for the study of protein-nucleic acid interactions. The association between proteins covalently labeled with dansyl chloride and DNA noncovalently labeled with acridine orange can be studied by monitoring the transfer of fluorescent energy from the donor (the dansyl label) to the acceptor (acridine orange). This method has been illustrated in model fluorescence studies which yield estimates of the combining ratio of histone VIIIS (Sigma, arginine rich) with DNA.