Mutation-induction in repair-deficient strains of Neurospora.

Various mutants sensitive to UV-induced inactivation have been used to study the process of spontaneous and induced mutation in the ad-3 region of Neurospora crassa. Studies on haploid strains have shown that the process of mutation-induction in the ad-3 region is under genetic control. Studies on two-component heterokaryons have shown that this control effects both point mutations and multilocus deletions. Comparisons made between an excision-repair deficient two-component heterokaryon (59) have shown that the level of effect is markedly mutagen-specific. All possible effects on the process of mutation-induction in the ad-3 region have been found in the strains tested.