Unknown,Transcriptomics,Genomics,Proteomics

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Transcriptional profiles of yeast on acetate exposed to pure nitrogen or carbon monoxide

ABSTRACT: Oxygen lack of various severity can force many organisms to enter into recoverable hypometabolic states. To better understand how organisms cope with oxygen deprivation, our lab had previously shown that when challenged with anoxia, both the nematode Caenorhabditis elegans and embryos of the zebrafish Danio rerio enter into suspended animation, where all life processes that can be observed by light microscopy reversibly halt, pending restoration of oxygen. Here, we show that both sporulating and vegetative cells of the budding yeast Saccharomyces cerevisiae also enter into a similar state of suspended animation when made anoxic on a non-fermentable carbon source. Transcriptional profiling using cDNA microarrays shows upregulation of aerobic metabolism genes in carbon monoxide (CO)-induced anoxia, but not nitrogen (N2) gas-induced anoxia, consistent with the known oxygen-mimetic effects of CO. Our results lead us to propose a model for oxygen-regulated gene expression in yeast where two oxygen-sensitive mechanisms operate simultaneously, such that treatment with N2 results in both mechanisms signaling a lack of oxygen, while treatment with CO results in one sensing mechanism signaling a lack of oxygen, while the other signals an abundance of oxygen. Cells were pregrown on glucose media. Cells were then plated onto nylon membranes on acetate solid media and made anoxic using either pure nitrogen or carbon monoxide. Cells were collected at 15, 30, 45, 60, 120 minutes and 24 hours after initiation of gas exposure. Reference samples were derived from cells on acetate in room air for corresponding time point. Six CO-treated samples were compared to room air references and six nitrogen-treated samples were similarly compared to room air references.

ORGANISM(S): Saccharomyces cerevisiae

SUBMITTER: Kin Chan

PROVIDER: E-GEOD-12004 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Anoxia-induced suspended animation in budding yeast as an experimental paradigm for studying oxygen-regulated gene expression.

Chan Kin K Roth Mark B MB

Eukaryotic cell 20080815 10

A lack of oxygen can force many organisms to enter into recoverable hypometabolic states. To better understand how organisms cope with oxygen deprivation, our laboratory previously had shown that when challenged with anoxia, both the nematode Caenorhabditis elegans and embryos of the zebrafish Danio rerio enter into suspended animation, in which all life processes that can be observed by light microscopy reversibly halt pending the restoration of oxygen (P. A. Padilla and M. B. Roth, Proc. Natl. ...[more]

PMID: 18708563

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Dataset Information

Transcriptional profiles of yeast on acetate exposed to pure nitrogen or carbon monoxide

Publications

Anoxia-induced suspended animation in budding yeast as an experimental paradigm for studying oxygen-regulated gene expression.

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