The number of cell generations required to fix the transformed state in X-ray-induced transformation.

Abstract

The number of cell generations required to fix the transformed state in X-ray-induced transformation was studied by allowing hamster cells to undergo a different number of cell generations after irradiation before the cultures became confluent, and then testing for the loss of fixation in the confluent cultures by the assay for transformed colonies. The results indicate that 2 cell generations are required for fixation of the transformed state. The cellular DNA has to replicate after irradiation to produce DNA strand that codes for transformation, and that the transformed state is then fixed in cells where both strands consist of this new type of DNA.