Okladnova O V, Georgiev P G
Genetika. 1992 Oct;28(10):83-94.
We have characterized the phenomenon of super-unstability in yellow and scute loci of Drosophila melanogaster. A few derivatives with different combinations of yellow and scute phenotypes appeared after dysgenic cross between potentially super-unstable stock y2nsscme and P[ry+, (delta 2-3)] (99B). Essentially, the double alterations of yellow and scute phenotypes constitute more than 40% of all derivatives. Most frequently the mutations in both yellow and scute loci change coordinately giving rise to the y+nssc+ allele. Lethal derivatives were not observed. The spectrum and the frequency of the y2nsscme mutagenesis in females differ considerably from the analogous in males. Possibly, the neutral homologous chromosome in females changes contacts between two insertions, and because of that mutagenesis changes too. Thus, all alterations in the double super-unstable system seem to be connected with the recombination between two unstable insertions A genetic exchange may by initiated by a double-strand breaks induced by the transposase of the ends of insertions.
我们已经对黑腹果蝇黄色和小盾片基因座中的超不稳定现象进行了表征。在潜在的超不稳定品系y2nsscme与P[ry +, (delta 2-3)] (99B)之间进行杂种不育杂交后，出现了一些具有不同黄色和小盾片表型组合的衍生物。本质上，黄色和小盾片表型的双重改变占所有衍生物的40%以上。最常见的是，黄色和小盾片基因座中的突变协同变化，产生y + nssc + 等位基因。未观察到致死性衍生物。雌性中y2nsscme诱变的谱和频率与雄性中的类似情况有很大差异。可能是雌性中的中性同源染色体会改变两个插入片段之间的接触，因此诱变也会发生变化。因此，双重超不稳定系统中的所有改变似乎都与两个不稳定插入片段之间的重组有关。遗传交换可能由插入片段末端的转座酶诱导的双链断裂引发。
