DNA-binding specificity of a chromatin non-histone protein fraction of HeLa cells

The DNA-binding site of a previously characterized non-histone chromosomal protein antigen(s) from HeLa cells was investigated for its species specificity. Treatment with large amounts of micrococcal nuclease abolishes immunoactivity, which can then be recovered by the subsequent addition of human or HeLa DNA to reconstitute the immune complex. Neither rat nor calif DNA exhibits this property, but DNA from monkey cells gives considerable activity. The antigen is not, however, detectable in monkey chromatin.