Project description:Saxitoxin is a potent neurotoxin produced by several species of dinoflagellates and cyanobacteria. The molecular target of saxitoxin in higher eukaryotes is the voltage-gated sodium channel; however, its target in lower eukaryotic organisms remains unknown. The goal of this study was to obtain the transcriptional fingerprint of the model lower eukaryote Saccharomyces cerevisiae upon exposure to saxitoxin to identify potential genes suitable for biomarker development. Microarray analyses identified multiple genes associated with copper and iron homeostasis and sulfur metabolism as significantly differentially expressed upon exposure to saxitoxin; these results were verified with quantitative reverse-transcriptase PCR (qRT-PCR). Additionally, the qRT-PCR assays were used to generate expression profiles in a subset of the differentially regulated genes across multiple exposure times and concentrations, the results of which demonstrated that overall, genes tended to respond in a consistent manner to the toxin. In general, the genes encoding the metallothioneins CUP1 and CRS5 were induced following exposure to saxitoxin, while those encoding the ferric/cupric reductase FRE1 and the copper uptake transporter CTR1 were repressed. The gene encoding the multicopper ferroxidase FET3, part of the high-affinity iron uptake system, was also induced in all treatments, along with the STR3 gene, which codes for the cystathionine beta-lyase found in the methionine biosynthetic pathway.
Project description:Saxitoxin is a potent neurotoxin produced by several species of dinoflagellates and cyanobacteria. The molecular target of saxitoxin in higher eukaryotes is the voltage-gated sodium channel; however, its target in lower eukaryotic organisms remains unknown. The goal of this study was to obtain the transcriptional fingerprint of the model lower eukaryote Saccharomyces cerevisiae upon exposure to saxitoxin to identify potential genes suitable for biomarker development. Microarray analyses identified multiple genes associated with copper and iron homeostasis and sulfur metabolism as significantly differentially expressed upon exposure to saxitoxin; these results were verified with quantitative reverse-transcriptase PCR (qRT-PCR). Additionally, the qRT-PCR assays were used to generate expression profiles in a subset of the differentially regulated genes across multiple exposure times and concentrations, the results of which demonstrated that overall, genes tended to respond in a consistent manner to the toxin. In general, the genes encoding the metallothioneins CUP1 and CRS5 were induced following exposure to saxitoxin, while those encoding the ferric/cupric reductase FRE1 and the copper uptake transporter CTR1 were repressed. The gene encoding the multicopper ferroxidase FET3, part of the high-affinity iron uptake system, was also induced in all treatments, along with the STR3 gene, which codes for the cystathionine beta-lyase found in the methionine biosynthetic pathway. Experiment Overall Design: Cultures of S. cerevisiae S288C were grown to OD600=1.0 in YPD (1% yeast extract, 2% peptone, 2% dextrose). Four hundred microliters from individual 10 mL overnight cultures were transferred to sterile tubes and saxitoxin added to a final concentration of 16 µM. Sample were mixed gently and incubated at 30° C for 45 min. Controls consisted of deionized water. Three biological replicates were performed under these conditions for microarray analysis. Cells were harvested via sequential centrifugation and placed immediately in liquid nitrogen.Total RNA was extracted from frozen cell pellets using a protocol that combined the hot acid phenol method with the RNEasy kit. Total RNA was processed by the Affymetrix Core Facility at the University of Tennessee (Knoxville, TN) following the protocols of the Affymetrix GeneChip Expression Analysis Technical Manual. MAS5.0 was used to provide present/absent calls; genes absent in all six samples were then removed from the data set. Intensity values for all transcripts were obtained from the scanned image files of the chips. The intensity values of the six arrays were background-corrected and normalized with the GC-RMA algorithm.
Project description:We report change in the nucleosome occupancy and accessibility upon deletion of ATP-dependent chromatin remodellers (ISW1, ISW2 & CHD1) in Saccharomyces cerevisiae.
Project description:We employed CapitalBio Corporation to investigate the global transcriptional profiling of Saccharomyces cerevisiae treated with allicin.
Project description:We employed CapitalBio Corporation to investigate the global transcriptional profiling of Saccharomyces cerevisiae treated with dictamnine. Keywords: response to dictamnine
Project description:We employed CapitalBio Corporation to investigate the global transcriptional profiling of Saccharomyces cerevisiae treated with thymol. Keywords: gene expression array-based, count
Project description:We report change in the chromatin contacts upon deletion of ATP-dependent chromatin remodellers (ISW1, ISW2 and CHD1) in Saccharomyces cerevisiae.
Project description:We report change in the chromatin contacts at nucleosomal resolution upon deletion of ATP-dependent chromatin remodellers(Isw1,Isw2 and Chd1) in Saccharomyces cerevisiae.