Transcriptomic profiling of S. cerevisiae wild type and aft2 mutant in response to exposure to selenite

The yeast S. cerevisiae does not require selenium for growth, so it is an excellent model to investigate the toxicity of this element without interference from its requirement as growth factor as occurs in animal cells. Exposure to selenite interferes with the yeast iron metabolism. Aft2 is a transcription factor related (with Aft1) to maintenance of iron homeostasis. We have found that aft2 cells are highly sensitive to selenite (a common environmental source for selenium). In these experiments we investigate the transcriptional response to a sub-lethal dose of selenite in wild type and aft2 cells. Our results show that the aft2 mutation strongly potentiates the transcriptional response to selenite, showing induction of many genes related to the responses to oxidative stress and DNA damage. Overall design: Wild type (W303-1A) background and its MML1086 derivative (Daft2) were exposed to 1 mm selenite and samples taken at time 0, 1, 3 and 5 h of selenite treatment. Two biological replicates were prepared for each time-point. Therefore, there are 8 samples per replicate (4 samples for WT and 4 samples for aft2 cells). The WT strain is used here as reference.

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