Formation and rejoining of DNA strand breaks in X (gamma)-irradiated cells in relation to the structure of mammalian chromatin.
Mammalian cells usually possess the capacity to rejoin disruptions introduced into their deoxynucleoprotein structures by ionizing radiation. I believe that analyses of the strand-break-inducing and the strand-break-rejoining mechanisms operating on the DNA of irradiated cells can provide clues to the nature of the structure of mammalian chromatin in situ. In particular, I wish to consider evidence relevant to the idea that mammalian DNA contains special sites which are sensitive to radiation (Left and Sun, 1970; Lett et al., 1972), alkali (Lett et al., 1970), and perhaps other agents and treatments. This concept is usually referred to as the "subunit hypothesis." The present communication extends previous arguments along similar lines (Lett et al., 1972) with an evaluation of more recent data. Since these data have been, or will be, published in the open literature or elsewhere in this book, they will be described here only in general terms.
D002460:Cell Line; D002843:Chromatin / Q000528:radiation effects*; D004247:DNA / Q000096:biosynthesis / Q000528:radiation effects*; D004260:DNA Repair; D008970:Molecular Weight; D011830:Radiation Effects
D002843:Chromatin; D004247:DNA