Expression data from diclofenac-treated yeast cells

Diclofenac is a widely used analgesic drug that can cause serious adverse drug reactions. We used Saccharomyces cerevisiae as model eukaryote to elucidate the molecular mechanisms of diclofenac toxicity and resistance. Although most yeast cells died during initial diclofenac treatment, some survived and started growing again. Microarray analysis of the adapted cells identified three major processes involved in diclofenac detoxification and tolerance. Especially pleiotropic drug resistance genes and genes under control of Rlm1p, a transcription factor in the protein kinase C (PKC) pathway, were upregulated in diclofenac-adapted cells. Genes involved in ribosome biogenesis and rRNA processing were downregulated, as well as zinc-responsive genes. Five independent yeast cultures were incubated with 100 µM diclofenac for 75 hours. Every 24h, cultures were diluted to OD600 ~0.1 in YNB containing 100 µM diclofenac. Five independent control cultures were grown in the absence of diclofenac.