For many years my laboratory has conducted research on the molecular biology of the adenovirus, a model cancer virus. Toward the end of my research career, I collaborated with Professor Merril to use yeast to study the role of p53 in preventing human cancer. Although yeast does not contain a p53 gene, a study done with the fission yeast Saccharomyces pombe found that high level expression of p53 in pombe arrested cell growth. A mutant circumventing the growth arrest of p53 was isolated and the gene was cloned. The gene encoded a homolog of thioredoxin reductase. This raised the possibility that p53 is subject to redox regulation and stimulted pursuit of the effect of thioredoxin reductase gene mutations on p53 transcriptional activity in S. cerevisiae.