RTI uses cookies to offer you the best experience online. By clicking “accept” on this website, you opt in and you agree to the use of cookies. If you would like to know more about how RTI uses cookies and how to manage them please view our Privacy Policy here. You can “opt out” or change your mind by visiting: http://optout.aboutads.info/. Click “accept” to agree.
X-ray-induced specific-locus mutations in the ad-3 region of two-component heterokaryons of Neurospora crassa.
VI. Induction kinetics of gene/point mutations, multilocus deletions and multiple-locus mutations
De Serres, F. J. (1990). X-ray-induced specific-locus mutations in the ad-3 region of two-component heterokaryons of Neurospora crassa. VI. Induction kinetics of gene/point mutations, multilocus deletions and multiple-locus mutations. Mutation Research - Fundamental and Molecular Mechanisms of Mutagenesis, 231(2), 109-124. https://doi.org/10.1016/0027-5107(90)90018-Y
Genetic fine-structure analysis of X-ray-induced specific-locus mutants in the ad-3 region of two-component heterokaryons of Neurospora crassa has shown that gene/point mutations, multilocus deletions and multiple-locus mutations are induced. When the dose-response curves for these classes of ad-3 mutants were plotted, it was demonstrated that X-ray-induced gene/point mutations (ad-3R) increased linearly with X-ray dose and X-ray-induced multilocus deletions increased as the square of the X-ray dose. However, all classes of multiple-locus mutations, which would be expected to result from 3 to 8 hits on the basis of target theory (Lea, 1955), were found to increase as the square of the dose. Target theory assumes that the DNA of individual chromosomes is distributed randomly throughout the interphase nucleus. A model of eukaryotic interphase chromosome structure in which the DNA of individual chromosomes presents a nonrandom target to X-rays [Pinkel et al., Proc. Natl. Acad. Sci. (U.S.A.) 83 (1986), 2934-2938] provides a possible explanation for the high frequency and dose-squared induction kinetics of the multiple-locus mutants induced by X-rays in the ad-3 region