Analysis of Early-scnRNAs of Tetrahymena
Ontology highlight
ABSTRACT:
ORGANISM(S): Tetrahymena thermophila
PROVIDER: GSE79849 | GEO | 2016/04/02
SECONDARY ACCESSION(S): PRJNA317177
REPOSITORIES: GEO
Similar Datasets
Project description:scnRNAs co-IPed with Twi1p from wild-type cells @3 hpm Small RNAs co-precipitated with the Argonaute protein Twi1p were analyzed by high-throughput sequencing
2016-04-02 | E-GEOD-79849 | biostudies-arrayexpress
Project description:In this study, we demonstrated that there is a novel, unanticipated mechanism regulating programmed DNA elimination: a genome-wide trans-recognition network for IES identification. In this mechanism, Early-scnRNAs produced from Type-A IESs in the MIC identify not only the IESs from which they are derived but also other IESs in trans to trigger the cis-spreading of Late-scnRNA production in the IESs. This cis-spreading of Late-scnRNA production requires heterochromatin formation . Furthermore, these Late-scnRNAs can recognize other IESs in trans. This “chain reaction” of Late-scnRNA production by the trans-recognition network most likely provides strong robustness in DNA elimination by buffering cell-to-cell variability in the initial Early-scnRNA populations.
2015-06-15 | GSE68455 | GEO
Project description:In this study, we demonstrated that there is a novel, unanticipated mechanism regulating programmed DNA elimination: a genome-wide trans-recognition network for IES identification. In this mechanism, Early-scnRNAs produced from Type-A IESs in the MIC identify not only the IESs from which they are derived but also other IESs in trans to trigger the cis-spreading of Late-scnRNA production in the IESs. This cis-spreading of Late-scnRNA production requires heterochromatin formation . Furthermore, these Late-scnRNAs can recognize other IESs in trans. This “chain reaction” of Late-scnRNA production by the trans-recognition network most likely provides strong robustness in DNA elimination by buffering cell-to-cell variability in the initial Early-scnRNA populations. 26 to 32-nt small RNAs from various mutants or from immuno precipitated with Argonaute proteins were analyzed by high-throughput sequencing
2015-06-15 | E-GEOD-68455 | biostudies-arrayexpress
Project description:The developmentally regulated 26- to 32-nt siRNAs (scnRNAs) are loaded to the Argonaute protein Twi1p and display a strong bias for uracil at the 5' end. In this study, we used deep sequencing to analyze loaded and unloaded populations of scnRNAs. We show that the size of the scnRNA is determined during a pre-loading process, whereas their 5' uracil bias is attributed to both pre-loading and loading processes. We also demonstrate that scnRNAs have a strong bias for adenine at the third base from the 3' terminus, suggesting that most scnRNAs are direct Dicer products. Furthermore, we show that the thermodynamic asymmetry of the scnRNA duplex does not affect the guide and passenger strand decision. Finally, we show that scnRNAs frequently have templated uracil at the last base without a strong bias for adenine at the second base indicating non-sequential production of scnRNAs from substrates. These findings provide a biochemical basis for the varying attributes of scnRNAs, which should help improve our understanding of the production and turnover of scnRNAs in vivo.
2013-06-05 | GSE47650 | GEO
Project description:The developmentally regulated 26- to 32-nt siRNAs (scnRNAs) are loaded to the Argonaute protein Twi1p and display a strong bias for uracil at the 5' end. In this study, we used deep sequencing to analyze loaded and unloaded populations of scnRNAs. We show that the size of the scnRNA is determined during a pre-loading process, whereas their 5' uracil bias is attributed to both pre-loading and loading processes. We also demonstrate that scnRNAs have a strong bias for adenine at the third base from the 3' terminus, suggesting that most scnRNAs are direct Dicer products. Furthermore, we show that the thermodynamic asymmetry of the scnRNA duplex does not affect the guide and passenger strand decision. Finally, we show that scnRNAs frequently have templated uracil at the last base without a strong bias for adenine at the second base indicating non-sequential production of scnRNAs from substrates. These findings provide a biochemical basis for the varying attributes of scnRNAs, which should help improve our understanding of the production and turnover of scnRNAs in vivo. We compared Twi1p-loaded scnRNAs to scnRNAs before they have been loaded into Twi1p by deep sequencing to understand how the two processes, the production of siRNAs by Dicer and the loading of siRNAs into Argonaute, shape the population of siRNAs in vivo.
2013-06-05 | E-GEOD-47650 | biostudies-arrayexpress
Project description:Analysis of genome-wide IES elimination of Late-scnRNA accumulation-defective cells inducates that Early-scnRNAs are sufficient to induce DNA elimination for a majority of IESs, whereas Late-scnRNAs are important for DNA elimination of some, mainly Type-B, IESs.
2015-06-15 | GSE68457 | GEO
Project description:To understand the importance of Giw1p in the loading of small RNAs to the Argonaute protein Twi1p in Tetrahymena, we compared Twi1p-bound small RNAs from wild-type cells and GIW1 KO cells. We found that the Twi1p-bound small RNA populations in wild-type cells and GIW1 KO cells are indistinguishable in their size distributions and base profiles. We immunopurified Twi1p-containing complex from wild-type and GIW1 KO cells and co-purified small RNAs were compared.
2014-09-23 | E-GEOD-61609 | biostudies-arrayexpress
Project description:To understand the importance of Giw1p in the loading of small RNAs to the Argonaute protein Twi1p in Tetrahymena, we compared Twi1p-bound small RNAs from wild-type cells and GIW1 KO cells. We found that the Twi1p-bound small RNA populations in wild-type cells and GIW1 KO cells are indistinguishable in their size distributions and base profiles.
2014-09-23 | GSE61609 | GEO
Project description:Analysis of genome-wide IES elimination of Late-scnRNA accumulation-defective cells inducates that Early-scnRNAs are sufficient to induce DNA elimination for a majority of IESs, whereas Late-scnRNAs are important for DNA elimination of some, mainly Type-B, IESs. new MACs of exconjugants were isolated from different mutants at 36 hpm, and the genomic DNA was analyzed by high-throughput sequencing
2015-06-15 | E-GEOD-68457 | biostudies-arrayexpress
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.
2016-07-15 | GSE83250 | GEO