title: Comparative studies of chloroplastic and nuclear DNA repair abilities after ultraviolet irradiation of Euglena gracilis.
abstract: Studies of nuclear and chloroplastic-DNA repair after ultraviolet irradiation of Euglena gracilis show that photoreactivation is very efficient at both the nuclear and chloroplastic level. Liquid-holding or split-dose experiments and treatment with caffeine reveal, furthermore, that dark-repair is very efficient in nuclear DNA but not in chloroplastic DNA (ctDNA). The possibility of a chloroplastic dark-repair of restricted efficiency is discussed. Determination of chloroplastic DNA content by reassociation kinetics indicates that an important degradation follows UV irradiation during liquid holding in the dark.
mesh_terms: D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism; D002736:Chloroplasts / Q000378:metabolism; D004247:DNA / Q000528:radiation effects*; D004260:DNA Repair; D004307:Dose-Response Relationship, Radiation; D005055:Euglena / Q000235:genetics*; D014466:Ultraviolet Rays
chemical_list: D004247:DNA