FIG. 5.

Relation between the recovery of thymidine and leucine incorporation under PAR and UV-A irradiation (as percentage of the incorporation rate after incubation for 4 h in the dark subsequent to UV-B exposure) and the dark recovery (calculated as percentage of activity measured immediately after UV-B exposure and at the end of the dark incubation for 4 h). The response measured in the PAR treatment was subtracted from that measured in the PAR plus UV-A treatment to distinguish between the photoreactivation induced by UV-A and that induced by PAR. Dotted lines denote the boundaries among the four categories of recovery from UV stress.