Whole-genome resequencing of wildtype and EMS-treated fission yeast Schizosaccharomyces pombe
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ABSTRACT: This experiment aims at analyzing crossover distribution genome-wise, in the fission yeast. S. pombe strains PR109 (h- leu1-32 ura4-D18) and PR110 (h+ leu1-32 ura4-D18) were used for three successive rounds of mutagenesis with Ethylmethane Sulfonate Mutagenesis. Five independent clones of the first round of mutagenesis were at the root of two subsequent similar rounds of mutagenesis. Each clone used was checked for its ability to mate and sporulate. Eventually, five mutagenized clones from each of the PR109 and PR110 backgrounds were sequenced to identify de novo mutations and determine the optimal combinations of mutation patterns for recombination analyses.
Project description:This experiment aims at analyzing crossover distribution genome-wise, in the fission yeast. S. pombe strains PR109 (h- leu1-32 ura4-D18) and PR110 (h+ leu1-32 ura4-D18) were used for three successive rounds of mutagenesis with Ethylmethane Sulfonate Mutagenesis. Five independent clones of the first round of mutagenesis were at the root of two subsequent similar rounds of mutagenesis. Each clone used was checked for its ability to mate and sporulate. Eventually, five mutagenized clones from each of the PR109 and PR110 backgrounds were sequenced to identify de novo mutations and determine the optimal combinations of mutation patterns for recombination analyses. The following h- x h+ crosses were selected and the corresponding tetrads dissected: BLP49 (A) x BLP23 (I), 29 tetrads; BLP59 (C) x BLP19 (H), 30 tetrads and BLP64 (D) x BLP33 (K), 33 tetrads.
Project description:The Upf1 RNA-binding protein is essential for nonsense-mediated decay (NMD). We compared wild type (ura4-D18 leu1-32 h-) and upfdelta (upf1delta::kanMX6 ura4-D18 leu1-32 h-) cells transcriptome under normal growth conditions
Project description:Int6/yin6 encodes the eIF3e subunits of the eukaryotic translation initiation factor 3 complex (eIF3). To assess the impact of eIF3e on the global transcriptome, RNA seq of total mRNA was performed. Total RNA was prepared from wildtype S. pombe (h- ura4-D18 leu1-32) and cells deleted for eif3e (int6, yin6, SPBC646.09c; h- int6::kanMX6 ura4-D18 leu1-32). Following rRNA depletion and library construction, samples were sequenced on the SOLID4 platform. Two replicates were analyzed and statistical analysis was performed to identify significant differences in mRNA levels.
Project description:The choice of growth media is a very important consideration of any cell-based proteomics experiment. Alterations thereof may result in differences in basal proteomes simply due to disparities in the metabolite composition of the media. We investigate the effect of growth media on the proteomes of three microorganisms, specifically E. coli, S. cerevisiae, and S. pombe, using tandem mass tag (TMT)-based quantitative proteomics. We compared the protein abundance profiles of these microorganisms propagated in two distinct growth media that are commonly used for the respective organism. Our sample preparation strategy included SP3 bead-assisted protein isolation and digestion. In addition, we assembled a replicate set of samples in which we altered the proteolytic digestion from sequential treatment with LysC and trypsin to only LysC. Despite differences in peptides identified and a drop in quantified proteins, the results were similar between the two datasets for all three microorganisms. Approximately 10% of the respective microbial proteomes were significantly altered in each dataset. As expected, gene ontology analysis revealed that the majority of differentially expressed proteins are implicated in metabolism. We emphasize further the importance of growth media selection and the potential consequences thereof.
Project description:Gene number of the fission yeast Schizosaccharomyces pombe is the lowest in free-living eukaryotes. We further reduced the gene number to examine a minimal gene set required for growth. The genome-reduced strain, named ASP3894, has four chromosomal deletion regions: 168.4 kb deletion in the left arm of chromosome 1 (ALT), 155.4 kb deletion in the right arm of chromosome 1 (ART), 211.7 kb deletion in the left arm of chromosome 2 (BLT) and 121.6 kb deletion in the right arm of chromosome 2 (BRT). As a result of the 657.3 kb genome reduction, 224 genes of approximately 5100 total genes were reduced. ASP3894 transcriptional profiling was compared with a parent strain, ASP3880, that is a non-genome-reduced strain to examine the influence of genome reduction. Three independent experiments. 3 control ASP3880 samples and 3 genome-reduced strain ASP3894 samples were independently grown in EMM medium and harvested at the logarithmic phase.
Project description:Gene regulation in response to intracellular calcium is mediated by the calcineurin-activated transcription factor Prz1 in the fission yeast Schizosaccharomyces pombe. Genome-wide studies of the Crz1 and CrzA fungal orthologs have uncovered numerous target genes involved in conserved and species-specific cellular processes. In contrast, very few target genes of Prz1 have been published. This paper identified an extensive list of genes using transcriptome and ChIP-chip analyses under inducing conditions of Prz1, including CaCl2, and tunicamycin treatment, as well as a âpmr1 genetic background. We identified 165 upregulated putative target genes of Prz1 in which the majority contained a calcium-dependent response element in their promoters, similar to that of the Saccharomyces cerevisiae ortholog Crz1. These genes were functionally enriched for Crz1-conserved processes such as cell wall biosynthesis. Overexpression of prz1+ increased resistance to the cell wall degradation enzyme zymolyase, likely from upregulation of the O-mannosyltransferase encoding gene omh1+. Loss of omh1+ abrogates this phenotype. We uncovered a novel inhibitory role in flocculation for Prz1. Loss of prz1+ resulted in constitutive flocculation and upregulation of genes encoding the flocculins Gsf2 and Pfl3, as well as the transcription factor Cbf12. The constitutive flocculation of the âprz1 strain was abrogated by the loss of gsf2+ or cbf12+. This study reveals that Prz1 functions as a positive and negative transcriptional regulator of genes involved in cell wall biosynthesis and flocculation, respectively. Moreover, comparison of target genes between Crz1/CrzA and Prz1 indicate some conservation in DNA-binding specificity, but also substantial rewiring of the calcineurin-mediated transcriptional-regulatory network. We generated 3 overexpression microarrays and 2 deletion microarrays with dye swaps, and 2 deletion microarrays with drug treatments with dye swaps, each with a biological replicate performed as a dye swap. The effect of the mutant strains were all compared to wild type or empty vector strains, except for one experiment where the prz1 deletion mutant was compared to the pmr1 deletion mutant.
Project description:The regulation of flocculation, surface adhesion and invasive growth in the fission yeast Schizosaccharomyces pombe has focused primarily at the transcriptional level, but little is known with regards to posttranscriptional control. Here, we identified the Pumilio protein Pfr1 as a novel posttranscriptional regulator of these processes. Deletion of pfr1+ prevented flocculation, surface adhesion and invasive growth under inducing conditions, while overexpression of pfr1+ was sufficient to trigger flocculation. The flocculent phenotype of pfr1+ overexpression was dependent on the presence of the Gsf2 flocculin, but not on the Mbx2, Cbf12 and Adn3 transcription factors. In addition, we used RNA immunoprecipitation and expression microarrays to identify pvg1+ and SPBPB7E8.01, which encode a galactose pyruvyltransferase and glycophosphatidylinositol membrane protein, respectively, as putative mRNA targets potentially degraded by Pfr1. The mRNAs of these genes were upregulated and downregulated in the pfr1 deletion and overexpression strains, respectively, and contained putative binding sites in the 3â-untranslated region. We also discovered that ccr4+ and ste13+, which encode components of the mRNA decay machinery, were required for these processes, but did not suppress the pfr1+ overexpression flocculent phenotype when deleted. This data suggest that these processes in S. pombe involve multiple posttranscriptional-regulatory pathways of which one requires Pfr1. We generated 2 overexpression microarrays with dye swap that were biological replicates, 2 deletion microarrys with dye swap. Mutants samples were compared to empty vector control or wild type. 1 RIP-chip array was generated with IP rna compared to total RNA from the sample.
Project description:Heterochromatin plays a key role in gene repression, maintaining genome integrity and chromosome segregation. Fission yeast, Schizosaccharomyces pombe, utilizes conserved components to direct heterochromatin formation using siRNA generated by RNA interference (RNAi) to guide a histone H3 lysine 9 methyltransferase to cognate chromatin. To identify compounds that inhibit heterochromatin formation, an in vivo phenotypic screen for loss of silencing was performed. A tester strain harbouring a silent dominant selectable kanMX reporter gene within fission yeast centromeric heterochromatin was used to screen a diverse library of chemicals. HMS-I1 and HMS-I2 were identified as compounds that reproducibly increased G418 resistance due to loss of kanMX silencing, and decreased the level of repressive H3K9 methylation on centromeric repeats. The pattern of changes induced by HMS-I1 and HMS-I2 were consistent with inhibition of the histone deacetylases (HDACs) Clr3 and/or Sir2. Chemical-genetic interactions and expression profiling indicated that both HMS-I1 and HMS-I2 affect the activity of the Clr3-containing Snf2/HDAC repressor complex (SHREC). Exposure to HMS-I1 was also found to alleviate silencing of reporter genes in an Arabidopsis transgenic plant line and a mouse cell line. HMS-I2 also disrupted reporter gene silencing in Arabidopsis. In vitro assays indicate that HMS-I1 impairs the activity of human HDAC6 and HDAC10. As HMS-I1 and HMS-I2 bear no resemblance to known inhibitors of chromatin-based activities they represent potentially novel and valuable reagents for experimental and therapeutic purposes. Our findings highlight the use of in vivo chemical screening conducted in fission yeast to identify compounds that disrupt heterochromatin across plant, fungi and animal kingdoms. 16 RNA samples: 2 replicates of WT untreated (vehicle DMSO) (KE1-A, KE2-A), HMS-I1 treated (KE1-B, KE2-B), HMS-I2 treated (KE1-C, KE2-C), and 2 additional replicates of WT (KE05_wt_1, KE10_wt_2), 4 replicates of clr2M-bM-^HM-^F (KE01_2118_1, KE06_2118_2, KE03_0080_1, KE08_0080_2) and mit1M-bM-^HM-^F (KE02_1295_1, KE07_1295_2, KE04_1278_1, KE09_1278_2).
Project description:In Schizosaccharomyces pombe, over 90% of transcription factor genes are nonessential. Moreover, the majority do not exhibit significant growth defects under optimal conditions when deleted, complicating their functional characterization and target gene identification. Here, we systematically overexpressed 99 transcription factor genes with the nmt1 promoter. Screening the overexpression array revealed that 64 transcription factor genes exhibited reduced fitness when ectopically expressed. Cell cycle defects were also often observed. We further investigated three uncharacterized transcription factor genes (toe1+-toe3+) which displayed cell elongation when overexpressed. Ectopic expression of toe1+ resulted in a G1 delay while toe2+ and toe3+ overexpression produced an accumulation of septated cells with abnormalities in septum formation and nuclear segregation, respectively. Transcriptome profiling and ChIP-chip analysis of the transcription factor overexpression strains indicated that Toe1 activates target genes of the pyrimidine-salvage pathway, while Toe3 regulates target genes involved in polyamine synthesis. We also found that ectopic expression of the putative target genes SPBC3H7.05c, and dad5+ and SPAC11D3.06 could recapitulate the cell cycle phenotypes of toe2+ and toe3+ overexpression, respectively. Furthermore, the phenotypes of toe1+and toe2+ overexpression could be suppressed by deletion of the putative target genes urg2+ and SPAC1399.04c, and SPBC3H7.05c, SPACUNK4.15 and rds1+, respectively. This study implicates new transcription factors and metabolism genes in cell cycle regulation and demonstrates the potential of systematic overexpression analysis to elucidate the function and target genes of transcription factors in S. pombe. We generated 3 overexpression microarrays and 2 deletion microarray with dye swaps, 3 deletion microarrays with drug treatments with dye swaps, 1 deletion single replicate microarray experiment, and 3 single replicate chIP-chip experiments. The effect of the mutant strains were all compared to wild type or empyty vector strains except for two experiments one that looked at the toe1 mutant with and without chlorpromazine and another that looked at wild type with and without chlorpromazine.