Action spectra for ultraviolet light-induced transformation of human cells to anchorage-independent growth.

We have determined action spectra for transformation of human embryonic skin and muscle fibroblasts to anchorage-independent growth. Tests under our experimental conditions indicate that reciprocity holds for photon rate and exposure time and that all the dose-effect curves in the wavelength range of 248 to 297 nm are smaller. These data can be used to construct action spectra with a maximum at about 265 nm, which do not implicate moieties other than nucleic acids as absorbers in the transformation process.