title: Effects of irradiation on RNA synthesis primed by calf thymus deoxyribonucleoprotein treated with salt and salt-urea.
abstract: 1. The effects of ionizing radiation on the activity of calf thymus templates were examined in a Escherichia coli RNA polymerase system. 2. The template activity of native and 2 M NaCl-5M urea-treated deoxyribonucleoproteins was enhanced by relatively low doses of irradiation, while that of 2 M NaCl-treated deoxyribonucleoprotein was not enhanced by irradiation. 3. The template activity of purified DNA was markedly decreased by irradiation, while that of native deoxyribonucleoprotein, 2 M NaCl-treated, and 2 M NaCl-5 M urea-treated ones were slightly decreased at a higher dose range. The doses for 50% inactivation of these templates were 1.3, 210, 140, and approximately 200 krad, respectively.
mesh_terms: D000818:Animals; D002417:Cattle; D003852:Deoxyribonucleoproteins / Q000378:metabolism / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D009698:Nucleoproteins / Q000528:radiation effects*; D011830:Radiation Effects; D011839:Radiation, Ionizing; D012965:Sodium Chloride / Q000494:pharmacology*; D013698:Templates, Genetic / Q000528:radiation effects; D013950:Thymus Gland / Q000187:drug effects / Q000378:metabolism*; D014158:Transcription, Genetic / Q000187:drug effects / Q000528:radiation effects*; D014508:Urea / Q000494:pharmacology*
chemical_list: D003852:Deoxyribonucleoproteins; D009698:Nucleoproteins; D012965:Sodium Chloride; D014508:Urea