Tetrahymena thermophila
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ABSTRACT:
PROVIDER: PRJNA287575 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Chromatin Immunoprecipitation sequencing of heterochromation associated proteins in Tetrahymena
| PRJNA325440 | ENA
Project description:In the ciliated protozoan Tetrahymena, de novo heterochromatin body formation is accompanied by programmed DNA elimination. We previously reported that dephosphorylation of the HP1-like protein Pdd1p is required for the formation of heterochromatin bodies during the process of programmed DNA elimination in the ciliated protozoan Tetrahymena. Here, we show that the heterochromatin body component Jub4p is required for Pdd1p phosphorylation, heterochromatin body formation and DNA elimination. Moreover, our analyses of unphosphorylatable Pdd1p mutants demonstrate that Pdd1p phosphorylation is required for heterochromatin body formation and DNA elimination, while it is dispensable for local heterochromatin assembly. Therefore, both phosphorylation and the following dephosphorylation of Pdd1p are necessary to facilitate the formation of heterochromatin bodies. We suggest that Jub4p-mediated phosphorylation of Pdd1p creates a chromatin environment that is a prerequisite for subsequent heterochromatin body assembly and DNA elimination. New macronuclei (MACs) of exconjugants were isolated from wild-type and various mutant cells at 12 hpm (hours post-mixing), sheared chromatin was immunoprecipitated andprecipitated DNA was analyzed by high-throughput sequencing
2016-07-15 | E-GEOD-83249 | biostudies-arrayexpress
Project description:Tetrahymena thermophila Twi8p-associated small RNAs
| PRJNA306046 | ENA
Project description:DNA elimination analysis of Tetrahymena cells defective in heterochromatin body formation
| PRJNA287581 | ENA
Project description:Analyses of heterochromatin distributions in the mutatnts defective in an RNAi-heterochromatin positive feedback loop in Tetrahymena [ChIP]
| PRJNA343283 | ENA
Project description:In the ciliated protozoan Tetrahymena, de novo heterochromatin body formation is accompanied by programmed DNA elimination. We previously reported that dephosphorylation of the HP1-like protein Pdd1p is required for the formation of heterochromatin bodies during the process of programmed DNA elimination in the ciliated protozoan Tetrahymena. Here, we show that the heterochromatin body component Jub4p is required for Pdd1p phosphorylation, heterochromatin body formation and DNA elimination. Moreover, our analyses of unphosphorylatable Pdd1p mutants demonstrate that Pdd1p phosphorylation is required for heterochromatin body formation and DNA elimination, while it is dispensable for local heterochromatin assembly. Therefore, both phosphorylation and the following dephosphorylation of Pdd1p are necessary to facilitate the formation of heterochromatin bodies. We suggest that Jub4p-mediated phosphorylation of Pdd1p creates a chromatin environment that is a prerequisite for subsequent heterochromatin body assembly and DNA elimination. 26 to 32-nt small RNAs from various mutants were analyzed by high-throughput sequencing
2016-07-15 | E-GEOD-83250 | biostudies-arrayexpress
Project description:In the ciliated protozoan Tetrahymena, de novo heterochromatin body formation is accompanied by programmed DNA elimination. Here, we show that the novel heterochromatin body component Jub1p promotes heterochromatin body formation and dephosphorylation of the Heterochromatin Protein 1 (HP1)-like protein Pdd1p. Through the identification and mutagenesis of the phosphorylated residues of Pdd1p, we demonstrate that Pdd1p dephosphorylation promotes the electrostatic interaction between Pdd1p and RNA in vitro and heterochromatin body formation in vivo. We therefore suggest that heterochromatin bodies are assembled by the Pdd1p-RNA interaction. Jub1p and Pdd1p dephosphorylation are required for heterochromatin body formation and DNA elimination but not for local heterochromatin assembly, indicating that heterochromatin body of itself plays an essential role in DNA elimination. New macronuclei (MACs) of exconjugants were isolated from wild-type different mutant cells at 12 hpm, shared chromatin was immunoprecipitated and precipitated DNA was analyzed by high-throughput sequencing.
2015-12-10 | E-GEOD-70081 | biostudies-arrayexpress
Project description:A conserved hallmark of eukaryotic chromatin architecture is the distinctive array of well-positioned nucleosomes downstream of transcription start sites (TSS). Recent studies indicate that trans-acting factors establish this stereotypical array. Here, we present the first genome-wide in vitro and in vivo nucleosome maps for the ciliate Tetrahymena thermophila. In contrast with previous studies in yeast, we find that the stereotypical nucleosome array is preserved in the in vitro reconstituted map, which is governed only by the DNA sequence preferences of nucleosomes. Remarkably, this average in vitro pattern arises from subsets of nucleosomes, rather than the whole array, being present in individual Tetrahymena genes. Variation in GC content contributes to the positioning of these sequence-directed nucleosomes, and affects codon usage and amino acid composition in genes. We propose that these ‘seed’ nucleosomes may aid the AT-rich Tetrahymena genome – which is intrinsically unfavorable for nucleosome formation – in establishing nucleosome arrays in vivo in concert with trans-acting factors, while minimizing changes to the coding sequences they are embedded within. All data are from the macronuclear genome. Datasets: 1) Log-phase cells, fixed chromatin, light MNase digest; 2) Log-phase cells, native chromatin, heavy MNase digest; 3) Starved cells, fixed chromatin, light MNase digest; 4) Starved cells, native chromatin, heavy MNase digest; 5) in vitro reconstituted chromatin, 50ul reaction, 4:10 histone:DNA ratio, light MNase digest; 6) in vitro reconstituted chromatin, 50ul reaction, 7:10 histone:DNA ratio, light MNase digest; 7) in vitro reconstituted chromatin, 150ul reaction, 4:10 histone:DNA ratio, light MNase digest; 8) in vitro reconstituted chromatin, 150ul reaction, 4:10 histone:DNA ratio, heavy MNase digest; Control dataset: 9): MNase-digested naked DNA
2015-07-30 | E-GEOD-64061 | biostudies-arrayexpress
Project description:Nucleosome mapping of Tetrahymena thermophila chromatin in vivo and in vitro
| PRJNA269988 | ENA