Cellular recovery, DNA repair and mutagenesis--a tale of two yeasts

In studies related to recovery and repair mechanisms following DNA damage, one problem that has been frequently addressed concerns the effects of DNA repair on both spontaneous and induced mutagenesis. Among the eukaryotic organisms which served as unique and valuable systems for investigating this problem are the two yeasts, Saccharomyces cerevisiae and Schizosaccharomyces pombe. With the basic genetics well worked out in both, these yeasts have provided the experimental tools for comparative analysis of mechanisms of DNA repair which show a great deal of diversity between the two unicellular eukaryotes. Since the present issue focuses on the contributions of R.H. Haynes to the area of DNA repair and mutagenesis, we have chosen to discuss those specific aspects of our studies which are directly or indirectly related to or influenced by his research in this field. These include: (i) liquid holding recovery, (ii) production of two strand mutations and the concept of heteroduplex repair, and (iii) understanding of pathways of repair through construction of supersensitive mutants in yeast.