Parameiosis in Aspergillus nidulans in response to doxorubicin

The recombinagenic effect of doxorubicin (an anticancer agent that impairs DNA synthesis and causes chromosome breaks) was used to induce parameiotic events in Aspergillus nidulans. Heterokaryons formed with master strains and uvs mutants were inoculated with and without doxorubicin. Haploid segregants (parameiotics and parents) and aneuploids were selected as heterokaryon-derived visible sectors. Among parameiotic segregants, recombinants by intergenic mitotic crossing-over and recombinants by chromosome-independent segregation were found. Whereas segregants of the former type were obtained only with doxorubicin, those of the latter type were recovered both with and without the drug.