[Action of aurantin on the chromosomal structure of continuous cultures of human amniotic cells (line A-1)].

When transplantable cultures of human amniotic cells, line A-1 were treated with auranthin in concentrations of 0.1 and 0.5 gamma/ml for 48 hours of their growth, the chromosomes in the methaphase proved to be not evently spiralized longitudinally and acquired the appearance of segmented structures. All the chromosomes in the set possessed the capacity for such segmentation. It was most pronounced near the centromers and at the ends of the meta- and submetacentric chromosomes. The acrocentric chromosomes were segmented longitudinally more evenly. Loose segments of the chromosomes most probably corresponded to the areas, in which auranthin binding with DNA occurred. The effect of auranthin on differentiation of the chromosomes longitudinally may be used, as it was indicated for actnomycin D, in identification of homological chromosomes in the karyotype, as well as in studies on the temporal sequence of DNA synthesis in the chromosomes.