DNA quaternary structure in the radiation sensitivity of human lymphocytes--a proposed role of copper.

On challenging with 2M NaCl, the nuclei of human lymphocytes yield an aggregate of DNA-protein material. The density of the material is less when isolated from irradiated cells than when isolated from unirradiated cells. The density of this material, designated histone-free-DNA (HF-DNA), from irradiated cells returns to that from unirradiated cells if the irradiated cells are allowed time at 37 degrees C in nutrient conditions. Lymphocyte …