title: The transcriptional response of Saccharomyces cerevisiae to Pichia membranifaciens killer toxin.
abstract: The transcriptional response of Saccharomyces cerevisiae to Pichia membranifaciens killer toxin (PMKT) was investigated. We explored the global gene expression responses of the yeast S. cerevisiae to PMKT using DNA microarrays, real time quantitative PCR, and Northern blot. We identified 146 genes whose expression was significantly altered in response to PMKT in a non-random functional distribution. The majority of induced genes, most of them related to the high osmolarity glycerol (HOG) pathway, were core environmental stress response genes, showing that the coordinated transcriptional response to PMKT is related to changes in ionic homeostasis. Hog1p was observed to be phosphorylated in response to PMKT implicating the HOG signaling pathway. Individually deleted mutants of both up- (99) and down-regulated genes (47) were studied for altered sensitivity; it was observed that the deletion of up-regulated genes generated hypersensitivity (82%) to PMKT. Deletion of down-regulated genes generated wild-type (36%), resistant (47%), and hypersensitive (17%) phenotypes. This is the first study that shows the existence of a transcriptional response to the poisoning effects of a killer toxin.
authors.affiliation: Department of Microbiology, Biology Faculty, University of Madrid, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Santos
authors.forename: María
authors.initials: M
authors.lastname: Del Mar Alvarez
authors.forename: Manuel San
authors.initials: MS
authors.lastname: Mauro
authors.forename: Concepción
authors.initials: C
authors.lastname: Abrusci
authors.forename: Domingo
authors.initials: D
authors.lastname: Marquina
mesh_terms: D015152:Blotting, Northern; D017353:Gene Deletion; D020869:Gene Expression Profiling; D006706:Homeostasis; D055646:Killer Factors, Yeast; D009183:Mycotoxins / Q000494:pharmacology*; D020411:Oligonucleotide Array Sequence Analysis; D009994:Osmolar Concentration; D016133:Polymerase Chain Reaction; D012441:Saccharomyces cerevisiae / Q000187:drug effects* / Q000235:genetics / Q000502:physiology; D015398:Signal Transduction; D014158:Transcription, Genetic
chemical_list: D055646:Killer Factors, Yeast; D009183:Mycotoxins; C087906:killer toxin, Pichia