title: The relation of radiation sensitivity to pronuclear chromosome structure. I. Different radiation sensitivities between Drosophila melanogaster and Phryne cincta.
abstract: After treatment of mature spermatozoa of Phryne cincta egg mortality rates were determined and chromosomal mutation rates by examination of the polytene chromosomes of the F1 progeny.--A comparison of the results with similar studies made on Drosophila melanogaster yielded a two- to threefold higher sensitivity in Phryne cincta. Evaluation of data concerning DNA amounts, heterochromatin contents, distribution of breaks, repair capacities in two-break sites and oxygen concentrations in mature spermatozoa revealed no contradiction to the hypothesis that the greater sensitivity of Phryne cincta is mainly due to a high degree of spiralization of the paternal pronucleus chromosomes.
mesh_terms: D000818:Animals; D002871:Chromosome Banding; D002875:Chromosomes / Q000528:radiation effects*; D004175:Diptera; D004307:Dose-Response Relationship, Radiation; D004331:Drosophila melanogaster; D005260:Female; D008297:Male; D009154:Mutation; D010063:Ovum / Q000528:radiation effects; D011836:Radiation Tolerance; D011995:Recombination, Genetic; D013045:Species Specificity; D013094:Spermatozoa / Q000528:radiation effects