Ultraviolet light induced thymine dimers and repair processes in the algaEudorina elegans

摘要

A fraction of the cellular DNA of the colonial green algaEudorina elegansstrain 1193 can be specifically labeled with3H-thymidine but not by3H-thymine. Ultraviolet (UV) irradiation ofE.elegansleads to the production of thymine dimers as determined by extraction, hydrolysis, and chromatography of3H-thymidine-labeled cells. Removal of dimers occurs by processes involving visible light (photoreactivation), but dark repair (excision repair) has not been detected in the labeled fraction. A relationship between UV exposure and thymine dimer production has been determined.